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Find video protocols related to scientific articles indexed in Pubmed.
Do Environmental Factors Modify the Genetic Risk of Prostate Cancer?
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 10-25-2014
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Background:Many single nucleotide polymorphisms (SNPs) influence prostate cancer (PCa) risk. To what extent genetic risk can be reduced by environmental factors is unknown. Methods:We evaluated effect modification by environmental factors of the association between susceptibility SNPs and PCa in 1,230 incident PCa cases and 1,362 controls, all white and similar ages, nested in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Trial. Genetic risk scores were calculated as number of risk alleles for 20 validated SNPs. We estimated the association between higher genetic risk (?12 SNPs) and PCa within environmental factor strata and tested for interaction. Results:Men with ?12 risk alleles had 1.98, 2.04, and 1.91 times the odds of total, advanced, and nonadvanced PCa, respectively. These associations were attenuated with use of selenium supplements, aspirin, ibuprofen, and higher vegetable intake. For selenium, the attenuation was most striking for advanced PCa: compared to <12 alleles and no selenium, the odds ratio (OR) for ?12 alleles was 2.06 (95% confidence interval [CI], 1.67-2.55) in nonusers and 0.99 (0.38-2.58) in users (P-interaction=0.031). Aspirin had the most marked attenuation for nonadvanced PCa: compared to <12 alleles and non-users, the OR for ?12 alleles was 2.25 (1.69-3.00) in nonusers and 1.70 (1.25-2.32) in users (P-interaction=0.009). This pattern was similar for ibuprofen (P-interaction=0.023) and vegetables (P-interaction=0.010). Conclusions:This study suggests that selenium supplements may reduce genetic risk of advanced PCa, while aspirin, ibuprofen, and vegetables may reduce genetic risk of nonadvanced PCa. Impact:The effect of genetic factors on PCa risk may vary by lifestyle interventions.
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Red meat intake, NAT2, and risk of colorectal cancer: A pooled analysis of 11 studies.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 10-25-2014
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Background: Red meat intake has been associated with risk of colorectal cancer (CRC), potentially mediated through heterocyclic amines. The metabolic efficiency of N-acetyltransferase 2 (NAT2) required for the metabolic activation of such amines is influenced by genetic variation. The interaction between red meat intake, NAT2 genotype, and CRC has been inconsistently reported. Methods: We used pooled individual-level data from the Colon Cancer Family Registry (CCFR) and the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO). Red meat intake was collected by each study. We inferred NAT2 phenotype based on polymorphism at rs1495741, highly predictive of enzyme activity. Interaction was assessed using multiplicative interaction terms in multivariate-adjusted models. Results: From 11 studies, 8,290 CRC cases and 9,115 controls were included. The highest quartile of red meat intake was associated with increased risk of CRC compared to the lowest quartile (OR 1.41, 95%CI 1.29 - 1.55). However, a significant association was observed only for studies with retrospective diet data, not for studies with diet prospectively assessed before cancer diagnosis. Combining all studies, high red meat intake was similarly associated with CRC in those with a rapid/intermediate NAT2 genotype (OR 1.38, 95%CI 1.20 - 1.59) as with a slow genotype (OR 1.43, 95%CI 1.28 - 1.61) (p- interaction=0.9). Conclusions: We found that high red meat intake was associated with increased risk of CRC only from retrospective case-control studies and not modified by NAT2 enzyme activity. Impact: Our results suggest no interaction between NAT2 genotype and red-meat intake in mediating risk of CRC.
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Monodisperse sphere-on-sphere silica particles for fast HPLC separation of peptides and proteins.
Analyst
PUBLISHED: 10-01-2014
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Monodisperse sphere-on-sphere (SOS) silica particles are produced in a one-pot reaction, removing the need for time-consuming preparation and classification steps. Analysis of peptides and proteins using HPLC displays faster separation at lower operating pressure than commercially available fused core materials.
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Fecal metabolomics: assay performance and association with colorectal cancer.
Carcinogenesis
PUBLISHED: 07-18-2014
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Metabolomic analysis of feces may provide insights on colorectal cancer (CRC) if assay performance is satisfactory. In lyophilized feces from 48 CRC cases, 102 matched controls, and 48 masked quality control specimens, 1043 small molecules were detected with a commercial platform. Assay reproducibility was good for 527 metabolites [technical intraclass correlation coefficient (ICC) >0.7 in quality control specimens], but reproducibility in 6-month paired specimens was lower for the majority of metabolites (within-subject ICC ?0.5). In the CRC cases and controls, significant differences (false discovery rate ?0.10) were found for 41 of 1043 fecal metabolites. Direct cancer association was found with three fecal heme-related molecules [covariate-adjusted 90th versus 10th percentile odds ratio (OR) = 17-345], 18 peptides/amino acids (OR = 3-14), palmitoyl-sphingomyelin (OR = 14), mandelate (OR = 3) and p-hydroxy-benzaldehyde (OR = 4). Conversely, cancer association was inverse with acetaminophen metabolites (OR <0.1), tocopherols (OR = 0.3), sitostanol (OR = 0.2), 3-dehydrocarnitine (OR = 0.4), pterin (OR = 0.3), conjugated-linoleate-18-2N7 (OR = 0.2), N-2-furoyl-glycine (OR = 0.3) and p-aminobenzoate (PABA, OR = 0.2). Correlations suggested an independent role for palmitoyl-sphingomyelin and a central role for PABA (which was stable over 6 months, within-subject ICC 0.67) modulated by p-hydroxy-benzaldehyde. Power calculations based on ICCs indicate that only 45% of metabolites with a true relative risk 5.0 would be found in prospectively collected, prediagnostic specimens from 500 cases and 500 controls. Thus, because fecal metabolites vary over time, very large studies will be needed to reliably detect associations of many metabolites that potentially contribute to CRC.
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Imputation and subset-based association analysis across different cancer types identifies multiple independent risk loci in the TERT-CLPTM1L region on chromosome 5p15.33.
Zhaoming Wang, Bin Zhu, Mingfeng Zhang, Hemang Parikh, Jinping Jia, Charles C Chung, Joshua N Sampson, Jason W Hoskins, Amy Hutchinson, Laurie Burdette, Abdisamad Ibrahim, Christopher Hautman, Preethi S Raj, Christian C Abnet, Andrew A Adjei, Anders Ahlbom, Demetrius Albanes, Naomi E Allen, Christine B Ambrosone, Melinda Aldrich, Pilar Amiano, Christopher Amos, Ulrika Andersson, Gerald Andriole, Irene L Andrulis, Cecilia Arici, Alan A Arslan, Melissa A Austin, Dalsu Baris, Donald A Barkauskas, Bryan A Bassig, Laura E Beane Freeman, Christine D Berg, Sonja I Berndt, Pier Alberto Bertazzi, Richard B Biritwum, Amanda Black, William Blot, Heiner Boeing, Paolo Boffetta, Kelly Bolton, Marie-Christine Boutron-Ruault, Paige M Bracci, Paul Brennan, Louise A Brinton, Michelle Brotzman, H Bas Bueno-de-Mesquita, Julie E Buring, Mary Ann Butler, Qiuyin Cai, Géraldine Cancel-Tassin, Federico Canzian, Guangwen Cao, Neil E Caporaso, Alfredo Carrato, Tania Carreon, Angela Carta, Gee-Chen Chang, I-Shou Chang, Jenny Chang-Claude, Xu Che, Chien-Jen Chen, Chih-Yi Chen, Chung-Hsing Chen, Constance Chen, Kuan-Yu Chen, Yuh-Min Chen, Anand P Chokkalingam, Lisa W Chu, Francoise Clavel-Chapelon, Graham A Colditz, Joanne S Colt, David Conti, Michael B Cook, Victoria K Cortessis, E David Crawford, Olivier Cussenot, Faith G Davis, Immaculata De Vivo, Xiang Deng, Ti Ding, Colin P Dinney, Anna Luisa Di Stefano, W Ryan Diver, Eric J Duell, Joanne W Elena, Jin-Hu Fan, Heather Spencer Feigelson, Maria Feychting, Jonine D Figueroa, Adrienne M Flanagan, Joseph F Fraumeni, Neal D Freedman, Brooke L Fridley, Charles S Fuchs, Manuela Gago-Dominguez, Steven Gallinger, Yu-Tang Gao, Susan M Gapstur, Montserrat Garcia-Closas, Reina Garcia-Closas, Julie M Gastier-Foster, J Michael Gaziano, Daniela S Gerhard, Carol A Giffen, Graham G Giles, Elizabeth M Gillanders, Edward L Giovannucci, Michael Goggins, Nalan Gokgoz, Alisa M Goldstein, Carlos González, Richard Gorlick, Mark H Greene, Myron Gross, H Barton Grossman, Robert Grubb, Jian Gu, Peng Guan, Christopher A Haiman, Göran Hallmans, Susan E Hankinson, Curtis C Harris, Patricia Hartge, Claudia Hattinger, Richard B Hayes, Qincheng He, Lee Helman, Brian E Henderson, Roger Henriksson, Judith Hoffman-Bolton, Chancellor Hohensee, Elizabeth A Holly, Yun-Chul Hong, Robert N Hoover, H Dean Hosgood, Chin-Fu Hsiao, Ann W Hsing, Chao Agnes Hsiung, Nan Hu, Wei Hu, Zhibin Hu, Ming-Shyan Huang, David J Hunter, Peter D Inskip, Hidemi Ito, Eric J Jacobs, Kevin B Jacobs, Mazda Jenab, Bu-Tian Ji, Christoffer Johansen, Mattias Johansson, Alison Johnson, Rudolf Kaaks, Ashish M Kamat, Aruna Kamineni, Margaret Karagas, Chand Khanna, Kay-Tee Khaw, Christopher Kim, In-Sam Kim, Jin Hee Kim, Yeul Hong Kim, Young-Chul Kim, Young Tae Kim, Chang Hyun Kang, Yoo Jin Jung, Cari M Kitahara, Alison P Klein, Robert Klein, Manolis Kogevinas, Woon-Puay Koh, Takashi Kohno, Laurence N Kolonel, Charles Kooperberg, Christian P Kratz, Vittorio Krogh, Hideo Kunitoh, Robert C Kurtz, Nilgun Kurucu, Qing Lan, Mark Lathrop, Ching C Lau, Fernando Lecanda, Kyoung-Mu Lee, Maxwell P Lee, Loic Le Marchand, Seth P Lerner, Donghui Li, Linda M Liao, Wei-Yen Lim, Dongxin Lin, Jie Lin, Sara Lindstrom, Martha S Linet, Jolanta Lissowska, Jianjun Liu, Börje Ljungberg, Josep Lloreta, Daru Lu, Jing Ma, Nuria Malats, Satu Mannisto, Neyssa Marina, Giuseppe Mastrangelo, Keitaro Matsuo, Katherine A McGlynn, Roberta Mckean-Cowdin, Lorna H McNeill, Robert R McWilliams, Beatrice S Melin, Paul S Meltzer, James E Mensah, Xiaoping Miao, Dominique S Michaud, Alison M Mondul, Lee E Moore, Kenneth Muir, Shelley Niwa, Sara H Olson, Nick Orr, Salvatore Panico, Jae Yong Park, Alpa V Patel, Ana Patiño-García, Sofia Pavanello, Petra H M Peeters, Beata Peplonska, Ulrike Peters, Gloria M Petersen, Piero Picci, Malcolm C Pike, Stefano Porru, Jennifer Prescott, Xia Pu, Mark P Purdue, You-Lin Qiao, Preetha Rajaraman, Elio Riboli, Harvey A Risch, Rebecca J Rodabough, Nathaniel Rothman, Avima M Ruder, Jeong-Seon Ryu, Marc Sanson, Alan Schned, Fredrick R Schumacher, Ann G Schwartz, Kendra L Schwartz, Molly Schwenn, Katia Scotlandi, Adeline Seow, Consol Serra, Massimo Serra, Howard D Sesso, Gianluca Severi, Hongbing Shen, Min Shen, Sanjay Shete, Kouya Shiraishi, Xiao-Ou Shu, Afshan Siddiq, Luis Sierrasesúmaga, Sabina Sierri, Alan Dart Loon Sihoe, Debra T Silverman, Matthias Simon, Melissa C Southey, Logan Spector, Margaret Spitz, Meir Stampfer, Pär Stattin, Mariana C Stern, Victoria L Stevens, Rachael Z Stolzenberg-Solomon, Daniel O Stram, Sara S Strom, Wu-Chou Su, Malin Sund, Sook Whan Sung, Anthony Swerdlow, Wen Tan, Hideo Tanaka, Wei Tang, Ze-Zhang Tang, Adonina Tardón, Evelyn Tay, Philip R Taylor, Yao Tettey, David M Thomas, Roberto Tirabosco, Anne Tjonneland, Geoffrey S Tobias, Jorge R Toro, Ruth C Travis, Dimitrios Trichopoulos, Rebecca Troisi, Ann Truelove, Ying-Huang Tsai, Margaret A Tucker, Rosario Tumino, David Van Den Berg, Stephen K Van Den Eeden, Roel Vermeulen, Paolo Vineis, Kala Visvanathan, Ulla Vogel, Chaoyu Wang, Chengfeng Wang, Junwen Wang, Sophia S Wang, Elisabete Weiderpass, Stephanie J Weinstein, Nicolas Wentzensen, William Wheeler, Emily White, John K Wiencke, Alicja Wolk, Brian M Wolpin, Maria Pik Wong, Margaret Wrensch, Chen Wu, Tangchun Wu, Xifeng Wu, Yi-Long Wu, Jay S Wunder, Yong-Bing Xiang, Jun Xu, Hannah P Yang, Pan-Chyr Yang, Yasushi Yatabe, Yuanqing Ye, Edward D Yeboah, Zhihua Yin, Chen Ying, Chong-Jen Yu, Kai Yu, Jian-Min Yuan, Krista A Zanetti, Anne Zeleniuch-Jacquotte, Wei Zheng, Baosen Zhou, Lisa Mirabello, Sharon A Savage, Peter Kraft, Stephen J Chanock, Meredith Yeager, Maria Terese Landi, Jianxin Shi, Nilanjan Chatterjee, Laufey T Amundadottir.
Hum. Mol. Genet.
PUBLISHED: 07-15-2014
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Genome-wide association studies (GWAS) have mapped risk alleles for at least 10 distinct cancers to a small region of 63 000 bp on chromosome 5p15.33. This region harbors the TERT and CLPTM1L genes; the former encodes the catalytic subunit of telomerase reverse transcriptase and the latter may play a role in apoptosis. To investigate further the genetic architecture of common susceptibility alleles in this region, we conducted an agnostic subset-based meta-analysis (association analysis based on subsets) across six distinct cancers in 34 248 cases and 45 036 controls. Based on sequential conditional analysis, we identified as many as six independent risk loci marked by common single-nucleotide polymorphisms: five in the TERT gene (Region 1: rs7726159, P = 2.10 × 10(-39); Region 3: rs2853677, P = 3.30 × 10(-36) and PConditional = 2.36 × 10(-8); Region 4: rs2736098, P = 3.87 × 10(-12) and PConditional = 5.19 × 10(-6), Region 5: rs13172201, P = 0.041 and PConditional = 2.04 × 10(-6); and Region 6: rs10069690, P = 7.49 × 10(-15) and PConditional = 5.35 × 10(-7)) and one in the neighboring CLPTM1L gene (Region 2: rs451360; P = 1.90 × 10(-18) and PConditional = 7.06 × 10(-16)). Between three and five cancers mapped to each independent locus with both risk-enhancing and protective effects. Allele-specific effects on DNA methylation were seen for a subset of risk loci, indicating that methylation and subsequent effects on gene expression may contribute to the biology of risk variants on 5p15.33. Our results provide strong support for extensive pleiotropy across this region of 5p15.33, to an extent not previously observed in other cancer susceptibility loci.
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Gene-environment interaction involving recently identified colorectal cancer susceptibility Loci.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 07-03-2014
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Genome-wide association studies have identified several single nucleotide polymorphisms (SNPs) that are associated with risk of colorectal cancer. Prior research has evaluated the presence of gene-environment interaction involving the first 10 identified susceptibility loci, but little work has been conducted on interaction involving SNPs at recently identified susceptibility loci, including: rs10911251, rs6691170, rs6687758, rs11903757, rs10936599, rs647161, rs1321311, rs719725, rs1665650, rs3824999, rs7136702, rs11169552, rs59336, rs3217810, rs4925386, and rs2423279.
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Injectable and oral contraceptives and risk of HIV acquisition in women: an analysis of data from the MDP301 trial.
Hum. Reprod.
PUBLISHED: 05-16-2014
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Do injectable and oral contraceptives increase the risk of human immunodeficiency virus (HIV) acquisition in women?
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Preparedness of Tanzanian health facilities for outpatient primary care of hypertension and diabetes: a cross-sectional survey.
Lancet Glob Health
PUBLISHED: 05-13-2014
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Historically, health facilities in sub-Saharan Africa have mainly managed acute, infectious diseases. Few data exist for the preparedness of African health facilities to handle the growing epidemic of chronic, noncommunicable diseases (NCDs). We assessed the burden of NCDs in health facilities in northwestern Tanzania and investigated the strengths of the health system and areas for improvement with regard to primary care management of selected NCDs.
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Comparison of methods for fecal microbiome biospecimen collection.
BMC Microbiol.
PUBLISHED: 04-14-2014
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Effective means are needed to efficiently collect fecal samples for microbiome analysis in large-scale epidemiological studies. Using twenty-four fecal aliquots prepared from three healthy individuals, we compared the following four fecal sample collection methods for assessment of human gut microbiome: 1) fecal occult blood test cards, held at room temperature for three days, 2) Eppendorf tubes, at room temperature for three days, 3) Eppendorf tubes with RNAlater, at room temperature, and 4) as controls, samples immediately frozen at -80°C. The 24 samples were assayed by 16S rRNA gene sequencing to compare overall microbiome structure and taxon distributions according to collection method.
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Genome-wide diet-gene interaction analyses for risk of colorectal cancer.
PLoS Genet.
PUBLISHED: 04-01-2014
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Dietary factors, including meat, fruits, vegetables and fiber, are associated with colorectal cancer; however, there is limited information as to whether these dietary factors interact with genetic variants to modify risk of colorectal cancer. We tested interactions between these dietary factors and approximately 2.7 million genetic variants for colorectal cancer risk among 9,287 cases and 9,117 controls from ten studies. We used logistic regression to investigate multiplicative gene-diet interactions, as well as our recently developed Cocktail method that involves a screening step based on marginal associations and gene-diet correlations and a testing step for multiplicative interactions, while correcting for multiple testing using weighted hypothesis testing. Per quartile increment in the intake of red and processed meat were associated with statistically significant increased risks of colorectal cancer and vegetable, fruit and fiber intake with lower risks. From the case-control analysis, we detected a significant interaction between rs4143094 (10p14/near GATA3) and processed meat consumption (OR = 1.17; p = 8.7E-09), which was consistently observed across studies (p heterogeneity = 0.78). The risk of colorectal cancer associated with processed meat was increased among individuals with the rs4143094-TG and -TT genotypes (OR = 1.20 and OR = 1.39, respectively) and null among those with the GG genotype (OR = 1.03). Our results identify a novel gene-diet interaction with processed meat for colorectal cancer, highlighting that diet may modify the effect of genetic variants on disease risk, which may have important implications for prevention.
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Core-shell particles: preparation, fundamentals and applications in high performance liquid chromatography.
J Chromatogr A
PUBLISHED: 03-31-2014
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The challenges in HPLC are fast and efficient separation for a wide range of samples. Fast separation often results in very high operating pressure, which places a huge burden on HPLC instrumentation. In recent years, core-shell silica microspheres (with a solid core and a porous shell, also known as fused-core or superficially porous microspheres) have been widely investigated and used for highly efficient and fast separation with reasonably low pressure for separation of small molecules, large molecules and complex samples. In this review, we firstly show the types of core-shell particles and how they are generally prepared, focusing on the methods used to produce core-shell silica particles for chromatographic applications. The fundamentals are discussed on why core-shell particles can perform better with low back pressure, in terms of van Deemter equation and kinetic plots. The core-shell particles are compared with totally porous silica particles and also monolithic columns. The use of columns packed with core-shell particles in different types of liquid chromatography is then discussed, followed by illustrating example applications of such columns for separation of various types of samples. The review is completed with conclusion and a brief perspective on future development of core-shell particles in chromatography.
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Understanding motives for intravaginal practices amongst Tanzanian and Ugandan women at high risk of HIV infection: the embodiment of social and cultural norms and well-being.
Soc Sci Med
PUBLISHED: 02-26-2014
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Some types of intravaginal practices (IVP) may increase the risk for HIV acquisition. This is particularly worrisome for populations with dual high prevalence of HIV and IVP. Women involved in transactional sex are at increased risk for HIV infection in sub-Saharan Africa. Social, cultural and economic influences are strong drivers of IVP in this population. To explore this, we carried out a qualitative research study to investigate the drivers and motivations for using IVP within a large observational study of women at high risk of HIV in Tanzania and Uganda from September 2008 to September 2009. Of the 201 women selected, 176 women took part in a semi-structured in-depth interview. Additionally, in Tanzania, eight focus group discussions among study participants and community members were carried out to obtain information on community norms and expectations. IVP were motivated by overlapping concerns with hygiene, morality, sexual pleasure, fertility, relationship security, and economic security. These motives were driven by the need to meet cultural and social expectations of womanhood, and at the same time attend to personal well-being. Among women involved in transactional sex in East Africa, interventions aimed at modifying or eliminating IVP should attend to local cultural and social norms as well as the individual as an agent of change.
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Estimating and explaining the effect of education and income on head and neck cancer risk: INHANCE consortium pooled analysis of 31 case-control studies from 27 countries.
Int. J. Cancer
PUBLISHED: 02-21-2014
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Low socioeconomic status has been reported to be associated with head and neck cancer risk. However, previous studies have been too small to examine the associations by cancer subsite, age, sex, global region and calendar time and to explain the association in terms of behavioral risk factors. Individual participant data of 23,964 cases with head and neck cancer and 31,954 controls from 31 studies in 27 countries pooled with random effects models. Overall, low education was associated with an increased risk of head and neck cancer (OR = 2.50; 95% CI = 2.02 - 3.09). Overall one-third of the increased risk was not explained by differences in the distribution of cigarette smoking and alcohol behaviors; and it remained elevated among never users of tobacco and nondrinkers (OR = 1.61; 95% CI = 1.13 - 2.31). More of the estimated education effect was not explained by cigarette smoking and alcohol behaviors: in women than in men, in older than younger groups, in the oropharynx than in other sites, in South/Central America than in Europe/North America and was strongest in countries with greater income inequality. Similar findings were observed for the estimated effect of low versus high household income. The lowest levels of income and educational attainment were associated with more than 2-fold increased risk of head and neck cancer, which is not entirely explained by differences in the distributions of behavioral risk factors for these cancers and which varies across cancer sites, sexes, countries and country income inequality levels.
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Estimating the heritability of colorectal cancer.
Hum. Mol. Genet.
PUBLISHED: 02-21-2014
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A sizable fraction of colorectal cancer (CRC) is expected to be explained by heritable factors, with heritability estimates ranging from 12 to 35% twin and family studies. Genome-wide association studies (GWAS) have successfully identified a number of common single-nucleotide polymorphisms (SNPs) associated with CRC risk. Although it has been shown that these CRC susceptibility SNPs only explain a small proportion of the genetic risk, it is not clear how much of the heritability these SNPs explain and how much is left to be detected by other, yet to be identified, common SNPs. Therefore, we estimated the heritability of CRC under different scenarios using Genome-Wide Complex Trait Analysis in the Genetics and Epidemiology of Colorectal Cancer Consortium including 8025 cases and 10 814 controls. We estimated that the heritability explained by known common CRC SNPs identified in GWAS was 0.65% (95% CI:0.3-1%; P = 1.11 × 10-16), whereas the heritability explained by all common SNPs was at least 7.42% (95% CI: 4.71-10.12%; P = 8.13 × 10(-8)), suggesting that many common variants associated with CRC risk remain to be detected. Comparing the heritability explained by the common variants with that from twin and family studies, a fraction of the heritability may be explained by other genetic variants, such as rare variants. In addition, our analysis showed that the gene × smoking interaction explained a significant proportion of the CRC variance (P = 1.26 × 10(-2)). In summary, our results suggest that known CRC SNPs only explain a small proportion of the heritability and more common SNPs have yet to be identified.
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Dietary iron, iron homeostatic gene polymorphisms and the risk of advanced colorectal adenoma and cancer.
Carcinogenesis
PUBLISHED: 02-17-2014
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Dietary iron intake and variation in iron homeostasis genes may affect colorectal neoplasia risk. We conducted two nested case-control studies within the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial: one of advanced colorectal adenoma (1205 cases; 1387 controls) and one of colorectal cancer (370 cases; 401 controls). Iron intake was estimated with a food frequency questionnaire and genotyping was performed for 21 genes. Unconditional logistic regression was used to estimate odds ratio (OR) and 95% confidence intervals (95% CIs) for colorectal neoplasia risk within quartiles of intake. Several single nucleotide polymorphisms (SNPs) modified the association between iron intake and the risk of adenoma or cancer. Dietary iron was positively associated with colorectal adenoma among three SNPs of HEPHL1, including carriers of the AA genotype at rs7946162 (ORQ4-Q1 = 2.22, 95% CI 1.15-4.27, Ptrend = 0.03; Pinteraction = 0.10), the TT genotype at rs2460063 (ORQ4-Q1 = 2.39, 95% CI 1.26-4.54, Ptrend = 0.02; Pinteraction = 0.04) and the GG genotype at rs7127348 (ORQ4-Q1 = 2.40, 95% CI 1.23-4.67, Ptrend = 0.02; Pinteraction = 0.09). Heme iron was positively associated with colorectal cancer among those with GG genotypes for ACO1 rs10970985 (ORQ4-Q 1 = 2.45, 95% CI 3.40-8.06, Ptrend = 0.004; Pinteraction = 0.05). However, none of the associations were statistically significant after adjustment for multiple comparisons. Future studies should target the specific genes and SNPs for which the association was significant prior to multiple comparison correction.
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HPTN 071 (PopART): rationale and design of a cluster-randomised trial of the population impact of an HIV combination prevention intervention including universal testing and treatment - a study protocol for a cluster randomised trial.
Trials
PUBLISHED: 02-03-2014
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Effective interventions to reduce HIV incidence in sub-Saharan Africa are urgently needed. Mathematical modelling and the HIV Prevention Trials Network (HPTN) 052 trial results suggest that universal HIV testing combined with immediate antiretroviral treatment (ART) should substantially reduce incidence and may eliminate HIV as a public health problem. We describe the rationale and design of a trial to evaluate this hypothesis.
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Fine-mapping the HOXB region detects common variants tagging a rare coding allele: evidence for synthetic association in prostate cancer.
PLoS Genet.
PUBLISHED: 02-01-2014
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The HOXB13 gene has been implicated in prostate cancer (PrCa) susceptibility. We performed a high resolution fine-mapping analysis to comprehensively evaluate the association between common genetic variation across the HOXB genetic locus at 17q21 and PrCa risk. This involved genotyping 700 SNPs using a custom Illumina iSelect array (iCOGS) followed by imputation of 3195 SNPs in 20,440 PrCa cases and 21,469 controls in The PRACTICAL consortium. We identified a cluster of highly correlated common variants situated within or closely upstream of HOXB13 that were significantly associated with PrCa risk, described by rs117576373 (OR 1.30, P?=?2.62×10(-14)). Additional genotyping, conditional regression and haplotype analyses indicated that the newly identified common variants tag a rare, partially correlated coding variant in the HOXB13 gene (G84E, rs138213197), which has been identified recently as a moderate penetrance PrCa susceptibility allele. The potential for GWAS associations detected through common SNPs to be driven by rare causal variants with higher relative risks has long been proposed; however, to our knowledge this is the first experimental evidence for this phenomenon of synthetic association contributing to cancer susceptibility.
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Well London Phase-1: results among adults of a cluster-randomised trial of a community engagement approach to improving health behaviours and mental well-being in deprived inner-city neighbourhoods.
J Epidemiol Community Health
PUBLISHED: 01-31-2014
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We report the main results, among adults, of a cluster-randomised-trial of Well London, a community-engagement programme promoting healthy eating, physical activity and mental well-being in deprived neighbourhoods. The hypothesis was that benefits would be neighbourhood-wide, and not restricted to intervention participants. The trial was part of a multicomponent process/outcome evaluation which included non-experimental components (self-reported behaviour change amongst participants, case studies and evaluations of individual projects) which suggested health, well-being and social benefits to participants.
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Epidemiology of curable sexually transmitted infections among women at increased risk for HIV in northwestern Tanzania: inadequacy of syndromic management.
PLoS ONE
PUBLISHED: 01-01-2014
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Curable, non-viral pathogens account for a significant burden of sexually transmitted infections (STIs), and there is established evidence that STIs increase both HIV acquisition and transmission. We investigated the prevalence, trends, and factors associated with Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and Treponema pallidum, and the performance of syndromic management, among a cohort of women working in bars, hotels, and other food and recreational facilities near large-scale mines in northwestern Tanzania.
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HPTN 071 (PopART): a cluster-randomized trial of the population impact of an HIV combination prevention intervention including universal testing and treatment: mathematical model.
PLoS ONE
PUBLISHED: 01-01-2014
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The HPTN 052 trial confirmed that antiretroviral therapy (ART) can nearly eliminate HIV transmission from successfully treated HIV-infected individuals within couples. Here, we present the mathematical modeling used to inform the design and monitoring of a new trial aiming to test whether widespread provision of ART is feasible and can substantially reduce population-level HIV incidence.
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Human gut microbiome and risk for colorectal cancer.
J. Natl. Cancer Inst.
PUBLISHED: 12-06-2013
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We tested the hypothesis that an altered community of gut microbes is associated with risk of colorectal cancer (CRC) in a study of 47 CRC case subjects and 94 control subjects. 16S rRNA genes in fecal bacterial DNA were amplified by universal primers, sequenced by 454 FLX technology, and aligned for taxonomic classification to microbial genomes using the QIIME pipeline. Taxonomic differences were confirmed with quantitative polymerase chain reaction and adjusted for false discovery rate. All statistical tests were two-sided. From 794217 16S rRNA gene sequences, we found that CRC case subjects had decreased overall microbial community diversity (P = .02). In taxonomy-based analyses, lower relative abundance of Clostridia (68.6% vs 77.8%) and increased carriage of Fusobacterium (multivariable odds ratio [OR] = 4.11; 95% confidence interval [CI] = 1.62 to 10.47) and Porphyromonas (OR = 5.17; 95% CI = 1.75 to 15.25) were found in case subjects compared with control subjects. Because of the potentially modifiable nature of the gut bacteria, our findings may have implications for CRC prevention.
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Metabolic dysregulation of the insulin-glucose axis and risk of obesity-related cancers in the Framingham heart study-offspring cohort (1971-2008).
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 09-24-2013
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Obesity-related dysregulation of the insulin-glucose axis is hypothesized in carcinogenesis. We studied impaired fasting glucose (IFG) and other markers of insulin-glucose metabolism in the Framingham Heart Study-Offspring Cohort, which uniquely tracks these markers and cancer >37 years.
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Impact of malaria and helminth infections on immunogenicity of the human papillomavirus-16/18 AS04-adjuvanted vaccine in Tanzania.
Vaccine
PUBLISHED: 09-17-2013
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Endemic malaria and helminth infections in sub-Saharan Africa can act as immunological modulators and impact responses to standard immunizations. We conducted a cohort study to measure the influence of malaria and helminth infections on the immunogenicity of the bivalent HPV-16/18 vaccine.
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Genetic predictors of circulating 25-hydroxyvitamin d and risk of colorectal cancer.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 08-27-2013
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Experimental evidence has demonstrated an antineoplastic role for vitamin D in the colon, and higher circulating 25-hydroxyvitamin D [25(OH)D] levels are consistently associated with a lower risk of colorectal cancer. Genome-wide association studies have identified loci associated with levels of circulating 25(OH)D. The identified single-nucleotide polymorphisms (SNPs) from four gene regions collectively explain approximately 5% of the variance in circulating 25(OH)D.
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Pleiotropic effects of genetic risk variants for other cancers on colorectal cancer risk: PAGE, GECCO and CCFR consortia.
Gut
PUBLISHED: 08-09-2013
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Genome-wide association studies have identified a large number of single nucleotide polymorphisms (SNPs) associated with a wide array of cancer sites. Several of these variants demonstrate associations with multiple cancers, suggesting pleiotropic effects and shared biological mechanisms across some cancers. We hypothesised that SNPs previously associated with other cancers may additionally be associated with colorectal cancer. In a large-scale study, we examined 171 SNPs previously associated with 18 different cancers for their associations with colorectal cancer.
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Cigarette, cigar, and pipe smoking and the risk of head and neck cancers: pooled analysis in the International Head and Neck Cancer Epidemiology Consortium.
Am. J. Epidemiol.
PUBLISHED: 06-30-2013
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Cigar and pipe smoking are considered risk factors for head and neck cancers, but the magnitude of effect estimates for these products has been imprecisely estimated. By using pooled data from the International Head and Neck Cancer Epidemiology (INHANCE) Consortium (comprising 13,935 cases and 18,691 controls in 19 studies from 1981 to 2007), we applied hierarchical logistic regression to more precisely estimate odds ratios and 95% confidence intervals for cigarette, cigar, and pipe smoking separately, compared with reference groups of those who had never smoked each single product. Odds ratios for cigar and pipe smoking were stratified by ever cigarette smoking. We also considered effect estimates of smoking a single product exclusively versus never having smoked any product (reference group). Among never cigarette smokers, the odds ratio for ever cigar smoking was 2.54 (95% confidence interval (CI): 1.93, 3.34), and the odds ratio for ever pipe smoking was 2.08 (95% CI: 1.55, 2.81). These odds ratios increased with increasing frequency and duration of smoking (Ptrend ? 0.0001). Odds ratios for cigar and pipe smoking were not elevated among ever cigarette smokers. Head and neck cancer risk was elevated for those who reported exclusive cigar smoking (odds ratio = 3.49, 95% CI: 2.58, 4.73) or exclusive pipe smoking (odds ratio = 3.71, 95% CI: 2.59, 5.33). These results suggest that cigar and pipe smoking are independently associated with increased risk of head and neck cancers.
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Summary measures of adherence using pill counts in two HIV prevention trials: the need for standardisation in reporting.
AIDS Behav
PUBLISHED: 06-27-2013
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For trials of user-dependent HIV prevention products, accurate adherence measurements are essential to interpret and compare results across trials. We used pill count data from two recent HIV prevention trials of herpes simplex virus type 2 (HSV-2) suppression, to show that estimates of adherence vary substantially depending on assumptions that are made in analysing pill count data. We associate calculated adherence with biological markers of anti-HSV-2 activity. In both trials, calculated adherence varied considerably, depending on the summary measure used, and the handling of intervals with apparent over-adherence (fewer pills returned than expected), and unreturned pills. Intervals of apparent over-adherence were associated with reduced antiviral effects on biological markers of herpes reactivation, indicating these are likely to represent periods of non-adherence. Our results demonstrate the clear need for standardisation in reporting of adherence data that are based on pill counts.
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Innate immunity gene polymorphisms and the risk of colorectal neoplasia.
Carcinogenesis
PUBLISHED: 06-26-2013
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Inherited variation in genes that regulate innate immunity and inflammation may contribute to colorectal neoplasia risk. To evaluate this association, we conducted a nested case-control study of 451 colorectal cancer cases, 694 colorectal advanced adenoma cases and 696 controls of European descent within the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. A total of 935 tag single-nucleotide polymorphisms (SNPs) in 98 genes were evaluated. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association with colorectal neoplasia. Sixteen SNPs were associated with colorectal neoplasia risk at P < 0.01, but after adjustment for multiple testing, only rs2838732 (ITGB2) remained suggestively associated with colorectal neoplasia (OR(per T allele) = 0.68, 95% CI: 0.57-0.83, P = 7.7 × 10(-5), adjusted P = 0.07). ITGB2 codes for the CD18 protein in the integrin beta chain family. The ITGB2 association was stronger for colorectal cancer (OR(per T allele) = 0.41, 95% CI: 0.30-0.55, P = 2.4 × 10(-) (9)) than for adenoma (OR(per T allele) = 0.84, 95%CI: 0.69-1.03, P = 0.08), but it did not replicate in the validation study. The ITGB2 rs2838732 association was significantly modified by smoking status (P value for interaction = 0.003). Among never and former smokers, it was inversely associated with colorectal neoplasia (OR(per T allele) = 0.5, 95% CI: 0.37-0.69 and OR(per T allele) = 0.72, 95% CI: 0.54-0.95, respectively), but no association was seen among current smokers. Other notable findings were observed for SNPs in BPI/LBP and MYD88. Although the results need to be replicated, our findings suggest that genetic variation in inflammation-related genes may be related to the risk of colorectal neoplasia.
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Personality Disorder and Self-Rated Health: A Population-Based Cross-Sectional Survey.
J. Pers. Disord.
PUBLISHED: 06-24-2013
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Little is known about the impact of personality disorder (PD) on the health of people living in the community. The authors set out to examine the association between PD and general health, using a cross-sectional survey of a representative community sample in London, UK. A total of 1,698 adults aged 16 years or over from 1,075 randomly selected households were recruited and interviewed face-to-face by trained interviewers. Using multivariable logistic regression, the authors examined the cross-sectional association between PD screen status, as assessed by the Standardised Assessment of Personality-Abbreviated Scale (SAPAS), and self-rated health, adjusting for demographic and health covariates. Of the participants, 14.5% screened positively for PD. A greater proportion of those scoring positively for PD reported poor self-rated health, compared to screen negative participants (41.3% versus 15.0%). This association was reduced, but remained significant, after adjustment for potential confounders (unadjusted odds ratio (OR) = 3.99, 95% CI [2.93, 5.42]; fully adjusted OR = 1.53, 95% CI [1.02, 2.29]. Of note, subthreshold symptoms of PD were significantly associated with poor self-rated health (unadjusted OR per unit SAPAS score increment = 1.53, 95% CI [1.40, 1.67]; fully adjusted OR = 1.19, 95% CI [1.07, 1.33]. Furthermore, people screening positive for PD were more likely to report multiple (three or more) long-standing illnesses. The authors conclude that in the general population, individuals who are at high risk for PD are independently at increased risk of poor general health.
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Prospective investigation of body mass index, colorectal adenoma, and colorectal cancer in the prostate, lung, colorectal, and ovarian cancer screening trial.
J. Clin. Oncol.
PUBLISHED: 05-28-2013
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Obesity has consistently been linked to an increased risk of colorectal cancer, particularly among men. Whether body mass index (BMI) differentially influences the risk across the stages of colorectal cancer development remains unclear. We evaluated the associations of BMI with colorectal adenoma incidence, adenoma recurrence, and cancer in the context of a large screening trial, in which cases and controls had an equal chance for disease detection.
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Circulating adipokine levels and endometrial cancer risk in the prostate, lung, colorectal, and ovarian cancer screening trial.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 05-21-2013
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Circulating adipokine levels may be associated with endometrial cancer risk, yet few studies have evaluated these markers prospectively.
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Genome-wide analysis of BMI in adolescents and young adults reveals additional insight into the effects of genetic loci over the life course.
Hum. Mol. Genet.
PUBLISHED: 05-12-2013
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Genetic loci for body mass index (BMI) in adolescence and young adulthood, a period of high risk for weight gain, are understudied, yet may yield important insight into the etiology of obesity and early intervention. To identify novel genetic loci and examine the influence of known loci on BMI during this critical time period in late adolescence and early adulthood, we performed a two-stage meta-analysis using 14 genome-wide association studies in populations of European ancestry with data on BMI between ages 16 and 25 in up to 29 880 individuals. We identified seven independent loci (P < 5.0 × 10??) near FTO (P = 3.72 × 10?²³), TMEM18 (P = 3.24 × 10?¹?), MC4R (P = 4.41 × 10?¹?), TNNI3K (P = 4.32 × 10?¹¹), SEC16B (P = 6.24 × 10??), GNPDA2 (P = 1.11 × 10??) and POMC (P = 4.94 × 10??) as well as a potential secondary signal at the POMC locus (rs2118404, P = 2.4 × 10?? after conditioning on the established single-nucleotide polymorphism at this locus) in adolescents and young adults. To evaluate the impact of the established genetic loci on BMI at these young ages, we examined differences between the effect sizes of 32 published BMI loci in European adult populations (aged 18-90) and those observed in our adolescent and young adult meta-analysis. Four loci (near PRKD1, TNNI3K, SEC16B and CADM2) had larger effects and one locus (near SH2B1) had a smaller effect on BMI during adolescence and young adulthood compared with older adults (P < 0.05). These results suggest that genetic loci for BMI can vary in their effects across the life course, underlying the importance of evaluating BMI at different ages.
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Mortality from solid tumors among workers in formaldehyde industries: an update of the NCI cohort.
Am. J. Ind. Med.
PUBLISHED: 05-07-2013
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Formaldehyde, a widely used chemical, is considered a human carcinogen.
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Natural history of Mycoplasma genitalium infection in a cohort of female sex workers in Kampala, Uganda.
Sex Transm Dis
PUBLISHED: 04-17-2013
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There have been few studies of the natural history of Mycoplasma genitalium in women. We investigated patterns of clearance and recurrence of untreated M. genitalium infection in a cohort of female sex workers in Uganda.
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Association of obesity with cardiovascular disease mortality in the PLCO trial.
Prev Med
PUBLISHED: 04-13-2013
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Obesity is a risk factor for cardiovascular disease (CVD) mortality, but the association between obesity and specific causes of CVD mortality is still under investigation.
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Fine-mapping identifies multiple prostate cancer risk loci at 5p15, one of which associates with TERT expression.
Hum. Mol. Genet.
PUBLISHED: 03-27-2013
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Associations between single nucleotide polymorphisms (SNPs) at 5p15 and multiple cancer types have been reported. We have previously shown evidence for a strong association between prostate cancer (PrCa) risk and rs2242652 at 5p15, intronic in the telomerase reverse transcriptase (TERT) gene that encodes TERT. To comprehensively evaluate the association between genetic variation across this region and PrCa, we performed a fine-mapping analysis by genotyping 134 SNPs using a custom Illumina iSelect array or Sequenom MassArray iPlex, followed by imputation of 1094 SNPs in 22 301 PrCa cases and 22 320 controls in The PRACTICAL consortium. Multiple stepwise logistic regression analysis identified four signals in the promoter or intronic regions of TERT that independently associated with PrCa risk. Gene expression analysis of normal prostate tissue showed evidence that SNPs within one of these regions also associated with TERT expression, providing a potential mechanism for predisposition to disease.
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Germline variation in NCF4, an innate immunity gene, is associated with an increased risk of colorectal cancer.
Int. J. Cancer
PUBLISHED: 03-07-2013
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Chronic inflammation has been implicated in the etiology of colorectal adenoma and cancer; however, few key inflammatory genes mediating this relationship have been identified. In this study, we investigated the association of germline variation in innate immunity genes in relation to the risk of colorectal neoplasia. Our study was based on the analysis of samples collected from the prostate, lung, colorectal and ovarian (PLCO) Cancer Screening Trial. We investigated the association between 196 tag single nucleotide polymorphisms (SNPs) in 20 key innate immunity genes with risk of advanced colorectal adenoma and cancer in 719 adenoma cases, 481 cancer cases and 719 controls. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CIs). After Bonferroni correction, the AG/GG genotype of rs5995355, which is upstream of NCF4, was associated with an increased risk of colorectal cancer (OR?=?2.43, 95% CI?=?1.73-3.39; p?
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Adult height and head and neck cancer: a pooled analysis within the INHANCE Consortium.
Eur. J. Epidemiol.
PUBLISHED: 02-28-2013
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Several epidemiological studies have shown a positive association between adult height and cancer incidence. The only study conducted among women on mouth and pharynx cancer risk, however, reported an inverse association. This study aims to investigate the association between height and the risk of head and neck cancer (HNC) within a large international consortium of HNC. We analyzed pooled individual-level data from 24 case-control studies participating in the International Head and Neck Cancer Epidemiology Consortium. Odds ratios (ORs) and 95 % confidence intervals (CIs) were estimated separately for men and women for associations between height and HNC risk. Educational level, tobacco smoking, and alcohol consumption were included in all regression models. Stratified analyses by HNC subsites were performed. This project included 17,666 cases and 28,198 controls. We found an inverse association between height and HNC (adjusted OR per 10 cm height = 0.91, 95 % CI 0.86-0.95 for men; adjusted OR = 0.86, 95 % CI 0.79-0.93 for women). In men, the estimated OR did vary by educational level, smoking status, geographic area, and control source. No differences by subsites were detected. Adult height is inversely associated with HNC risk. As height can be considered a marker of childhood illness and low energy intake, the inverse association is consistent with prior studies showing that HNC occur more frequently among deprived individuals. Further studies designed to elucidate the mechanism of such association would be warranted.
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Alcohol use, mycoplasma genitalium, and other STIs associated With HIV incidence among women at high risk in Kampala, Uganda.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 02-27-2013
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In 2008, the first clinic for women involved in high-risk sexual behavior was established in Kampala, offering targeted HIV prevention. This article describes rates, determinants, and trends of HIV incidence over 3 years.
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Insulin-like growth factor pathway genes and blood concentrations, dietary protein and risk of prostate cancer in the NCI Breast and Prostate Cancer Cohort Consortium (BPC3).
Int. J. Cancer
PUBLISHED: 02-15-2013
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It has been hypothesized that a high intake of dairy protein may increase prostate cancer risk by increasing the production of insulin-like growth factor 1 (IGF-1). Several single nucleotide polymorphisms (SNPs) have been weakly associated with circulating concentrations of IGF-1 and IGF binding protein 3 (IGFBP-3), but none of these SNPs was associated with risk of prostate cancer. We examined whether an association between 16 SNPs associated with circulating IGF-1 or IGFBP-3 concentrations and prostate cancer exists within subgroups defined by dietary protein intake in 5,253 cases and 4,963 controls of European ancestry within the NCI Breast and Prostate Cancer Cohort Consortium (BPC3). The BPC3 includes nested case-control studies within large North-American and European cohorts. Per-allele odds ratios for prostate cancer for the SNPs were compared across tertiles of protein intake, which was expressed as the percentage of energy derived from total, animal, dairy or plant protein sources, using conditional logistic regression models. Total, animal, dairy and plant protein intakes were significantly positively associated with blood IGF-1 (p??0.10) or with risk of prostate cancer (p?>?0.20). After adjusting for multiple testing, the SNP-prostate cancer associations did not differ by intakes of protein, although two interactions by intake of plant protein were of marginal statistical significance [SSTR5 (somatostatin receptor 5)-rs197056 (uncorrected p for interaction, 0.001); SSTR5-rs197057 (uncorrected p for interaction, 0.002)]. We found no strong evidence that the associations between 16 IGF pathway SNPs and prostate cancer differed by intakes of dietary protein.
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Effect of genital herpes on cervicovaginal HIV shedding in women co-infected with HIV AND HSV-2 in Tanzania.
PLoS ONE
PUBLISHED: 02-11-2013
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To compare the presence and quantity of cervicovaginal HIV among HIV seropositive women with clinical herpes, subclinical HSV-2 infection and without HSV-2 infection respectively; to evaluate the association between cervicovaginal HIV and HSV shedding; and identify factors associated with quantity of cervicovaginal HIV.
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Identification of 23 new prostate cancer susceptibility loci using the iCOGS custom genotyping array.
Rosalind A Eeles, Ali Amin Al Olama, Sara Benlloch, Edward J Saunders, Daniel A Leongamornlert, Malgorzata Tymrakiewicz, Maya Ghoussaini, Craig Luccarini, Joe Dennis, Sarah Jugurnauth-Little, Tokhir Dadaev, David E Neal, Freddie C Hamdy, Jenny L Donovan, Ken Muir, Graham G Giles, Gianluca Severi, Fredrik Wiklund, Henrik Grönberg, Christopher A Haiman, Fredrick Schumacher, Brian E Henderson, Loic Le Marchand, Sara Lindstrom, Peter Kraft, David J Hunter, Susan Gapstur, Stephen J Chanock, Sonja I Berndt, Demetrius Albanes, Gerald Andriole, Johanna Schleutker, Maren Weischer, Federico Canzian, Elio Riboli, Tim J Key, Ruth C Travis, Daniele Campa, Sue A Ingles, Esther M John, Richard B Hayes, Paul D P Pharoah, Nora Pashayan, Kay-Tee Khaw, Janet L Stanford, Elaine A Ostrander, Lisa B Signorello, Stephen N Thibodeau, Dan Schaid, Christiane Maier, Walther Vogel, Adam S Kibel, Cezary Cybulski, Jan Lubiński, Lisa Cannon-Albright, Hermann Brenner, Jong Y Park, Radka Kaneva, Jyotsna Batra, Amanda B Spurdle, Judith A Clements, Manuel R Teixeira, Ed Dicks, Andrew Lee, Alison M Dunning, Caroline Baynes, Don Conroy, Melanie J Maranian, Shahana Ahmed, Koveela Govindasami, Michelle Guy, Rosemary A Wilkinson, Emma J Sawyer, Angela Morgan, David P Dearnaley, Alan Horwich, Robert A Huddart, Vincent S Khoo, Christopher C Parker, Nicholas J Van As, Christopher J Woodhouse, Alan Thompson, Tim Dudderidge, Chris Ogden, Colin S Cooper, Artitaya Lophatananon, Angela Cox, Melissa C Southey, John L Hopper, Dallas R English, Markus Aly, Jan Adolfsson, Jiangfeng Xu, Siqun L Zheng, Meredith Yeager, Rudolf Kaaks, W Ryan Diver, Mia M Gaudet, Mariana C Stern, Román Corral, Amit D Joshi, Ahva Shahabi, Tiina Wahlfors, Teuvo L J Tammela, Anssi Auvinen, Jarmo Virtamo, Peter Klarskov, Børge G Nordestgaard, M Andreas Røder, Sune F Nielsen, Stig E Bojesen, Afshan Siddiq, Liesel M Fitzgerald, Suzanne Kolb, Erika M Kwon, Danielle M Karyadi, William J Blot, Wei Zheng, Qiuyin Cai, Shannon K McDonnell, Antje E Rinckleb, Bettina Drake, Graham Colditz, Dominika Wokolorczyk, Robert A Stephenson, Craig Teerlink, Heiko Muller, Dietrich Rothenbacher, Thomas A Sellers, Hui-Yi Lin, Chavdar Slavov, Vanio Mitev, Felicity Lose, Srilakshmi Srinivasan, Sofia Maia, Paula Paulo, Ethan Lange, Kathleen A Cooney, Antonis C Antoniou, Daniel Vincent, Francois Bacot, Daniel C Tessier, , Zsofia Kote-Jarai, Douglas F Easton.
Nat. Genet.
PUBLISHED: 01-28-2013
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Prostate cancer is the most frequently diagnosed cancer in males in developed countries. To identify common prostate cancer susceptibility alleles, we genotyped 211,155 SNPs on a custom Illumina array (iCOGS) in blood DNA from 25,074 prostate cancer cases and 24,272 controls from the international PRACTICAL Consortium. Twenty-three new prostate cancer susceptibility loci were identified at genome-wide significance (P < 5 × 10(-8)). More than 70 prostate cancer susceptibility loci, explaining ?30% of the familial risk for this disease, have now been identified. On the basis of combined risks conferred by the new and previously known risk loci, the top 1% of the risk distribution has a 4.7-fold higher risk than the average of the population being profiled. These results will facilitate population risk stratification for clinical studies.
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Long-term consistent use of a vaginal microbicide gel among HIV-1 sero-discordant couples in a phase III clinical trial (MDP 301) in rural south-west Uganda.
Trials
PUBLISHED: 01-21-2013
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A safe and effective vaginal microbicide could substantially reduce HIV acquisition for women. Consistent gel use is, however, of great importance to ensure continued protection against HIV infection, even with a safe and effective microbicide. We assessed the long-term correlates of consistent gel use in the MDP 301 clinical trial among HIV-negative women in sero-discordant couples in south-west Uganda.
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Deciphering the Complex Distribution of Human Immunodeficiency Virus Type 1 Subtypes among Different Cohorts in Northern Tanzania.
PLoS ONE
PUBLISHED: 01-01-2013
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Increased understanding of the genetic diversity of HIV-1 is challenging but important in the development of an effective vaccine. We aimed to describe the distribution of HIV-1 subtypes in northern Tanzania among women enrolled in studies preparing for HIV-1 prevention trials (hospitality facility-worker cohorts), and among men and women in an open cohort demographic surveillance system (Kisesa cohort).
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Respondent driven sampling: determinants of recruitment and a method to improve point estimation.
PLoS ONE
PUBLISHED: 01-01-2013
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Respondent-driven sampling (RDS) is a variant of a link-tracing design intended for generating unbiased estimates of the composition of hidden populations that typically involves giving participants several coupons to recruit their peers into the study. RDS may generate biased estimates if coupons are distributed non-randomly or if potential recruits present for interview non-randomly. We explore if biases detected in an RDS study were due to either of these mechanisms, and propose and apply weights to reduce bias due to non-random presentation for interview.
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Physical activity in deprived communities in london: examining individual and neighbourhood-level factors.
PLoS ONE
PUBLISHED: 01-01-2013
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The objectives of this study were to examine relationships between neighbourhood-level and individual-level characteristics and physical activity in deprived London neighbourhoods.
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The epidemiology of HIV and HSV-2 infections among women participating in microbicide and vaccine feasibility studies in Northern Tanzania.
PLoS ONE
PUBLISHED: 01-01-2013
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To prepare for future HIV prevention trials, we conducted prospective cohort studies among women working in food and recreational facilities in northern Tanzania. We examined the prevalence and incidence of HIV and HSV-2, and associated risk factors.
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Association between oral health and gastric precancerous lesions.
Carcinogenesis
PUBLISHED: 12-01-2011
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Although recent studies have suggested that tooth loss is positively related to the risk of gastric non-cardia cancer, the underlying oral health conditions potentially responsible for the association remain unknown. We investigated whether clinical and behavioral measures of oral health are associated with the risk of gastric precancerous lesions. We conducted a cross-sectional study of 131 patients undergoing upper gastrointestinal endoscopy. Cases were defined as those with gastric precancerous lesions including intestinal metaplasia or chronic atrophic gastritis on the basis of standard biopsy review. A validated structured questionnaire was administered to obtain information on oral health behaviors. A comprehensive clinical oral health examination was performed on a subset of 91 patients to evaluate for periodontal disease and dental caries experience. A total of 41 (31%) cases of gastric precancerous lesions were identified. Compared with non-cases, cases were significantly more likely to not floss their teeth [odds ratio (OR) = 2.89, 95% confidence interval (CI): 1.09-7.64], adjusting for age, sex, race, body mass index, smoking status, educational attainment and Helicobacter pylori status in serum. Among participants who completed the oral examination, cases (n = 28) were more likely to have a higher percentage of sites with gingival bleeding than non-cases [OR = 2.63, 95% CI: 1.37-5.05 for a standard deviation increase in bleeding sites (equivalent to 19.7%)], independent of potential confounders. Our findings demonstrate that specific oral health conditions and behaviors such as gingival bleeding and tooth flossing are associated with gastric precancerous lesions.
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Prevalence and correlates of Mycoplasma genitalium infection among female sex workers in Kampala, Uganda.
J. Infect. Dis.
PUBLISHED: 11-18-2011
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The importance of Mycoplasma genitalium in human immunodeficiency virus (HIV)-burdened sub-Saharan Africa is relatively unknown. We assessed the prevalence and explored determinants of this emerging sexually transmitted infection (STI) in high-risk women in Uganda.
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Universal testing and treatment as an HIV prevention strategy: research questions and methods.
Curr. HIV Res.
PUBLISHED: 07-15-2011
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Achieving high coverage of antiretroviral treatment (ART) in resource-poor settings will become increasingly difficult unless HIV incidence can be reduced substantially. Universal voluntary counselling and testing followed by immediate initiation of ART for all those diagnosed HIV-positive (universal testing and treatment, UTT) has the potential to reduce HIV incidence dramatically but would be very challenging and costly to deliver in the short term. Early modelling work in this field has been criticised for making unduly optimistic assumptions about the uptake and coverage of interventions. In future work, it is important that model parameters are realistic and based where possible on empirical data. Rigorous research evidence is needed before the UTT approach could be considered for wide-scale implementation. This paper reviews the main areas that need to be explored. We consider in turn research questions related to the provision of services for universal testing, services for immediate treatment of HIV-positives and the population-level impact of UTT, and the research methods that could be used to address these questions. Ideally, initial feasibility studies should be carried out to investigate the acceptability, feasibility and uptake of UTT services. If these studies produce promising results, there would be a strong case for a cluster-randomised trial to measure the impact of a UTT intervention on HIV incidence, and we consider the main design features of such a trial.
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Genome-wide association study identifies new prostate cancer susceptibility loci.
Hum. Mol. Genet.
PUBLISHED: 07-08-2011
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Prostate cancer (PrCa) is the most common non-skin cancer diagnosed among males in developed countries and the second leading cause of cancer mortality, yet little is known regarding its etiology and factors that influence clinical outcome. Genome-wide association studies (GWAS) of PrCa have identified at least 30 distinct loci associated with small differences in risk. We conducted a GWAS in 2782 advanced PrCa cases (Gleason grade ? 8 or tumor stage C/D) and 4458 controls with 571 243 single nucleotide polymorphisms (SNPs). Based on in silico replication of 4679 SNPs (Stage 1, P < 0.02) in two published GWAS with 7358 PrCa cases and 6732 controls, we identified a new susceptibility locus associated with overall PrCa risk at 2q37.3 (rs2292884, P= 4.3 × 10(-8)). We also confirmed a locus suggested by an earlier GWAS at 12q13 (rs902774, P= 8.6 × 10(-9)). The estimated per-allele odds ratios for these loci (1.14 for rs2292884 and 1.17 for rs902774) did not differ between advanced and non-advanced PrCa (case-only test for heterogeneity P= 0.72 and P= 0.61, respectively). Further studies will be needed to assess whether these or other loci are differentially associated with PrCa subtypes.
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Global levels of histone modifications in peripheral blood mononuclear cells of subjects with exposure to nickel.
Environ. Health Perspect.
PUBLISHED: 06-28-2011
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Occupational exposure to nickel (Ni) is associated with an increased risk for lung and nasal cancers. Ni compounds exhibit weak mutagenic activity, cause gene amplification, and disrupt cellular epigenetic homeostasis. However, the Ni-induced changes in global histone modification levels have only been tested in vitro.
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Serum IGF1, IGF2 and IGFBP3 and risk of advanced colorectal adenoma.
Int. J. Cancer
PUBLISHED: 06-27-2011
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The insulin-like growth factor (IGF) signaling pathway is involved in cell proliferation and differentiation. Elevated serum IGF1 levels have been associated with increased colorectal cancer risk; however, studies of this association with colorectal adenoma are inconclusive. We examined serum IGF1, IGF2 and IGFBP3 levels in relation to risk of advanced colorectal adenoma in a case-control study within the prostate, lung, colorectal and ovarian cancer screening trial. A total of 764 advanced, left-sided colorectal adenoma cases and 775 controls frequency-matched on gender and ethnicity, without evidence of a left-sided polyp on sigmoidoscopy were included in the current study. Serum levels of IGF1, IGF2 and IGFBP3 were measured using an enzyme linked immunosorbent assay in serum samples collected at baseline. Logistic regression was used to estimate the odds ratios (OR) and 95% confidence intervals (CI) for the associations adjusting for age, race, sex, year of blood draw, body mass index, smoking and education. Higher IGF1 levels were associated with increased adenoma risk: ORs = 1.58 (95% CI = 1.16-2.16), 1.42 (95% CI = 1.04-1.93), and 1.80 (95% CI = 1.30-2.47) for the second, third and fourth quartiles, respectively (p(trend) = 0.002). Elevated IGF2 levels were also associated with increased adenoma risk (OR = 1.43, 95% CI = 1.05-1.96 for the fourth vs. first quartile, p(trend) = 0.02), but the association was no longer significant after adjustment for IGF1 (p(trend) = 0.28). IGFBP3 levels were not associated with adenoma risk. Our analysis showed a significant positive association between circulating IGF1 levels and risk of advanced colorectal adenoma, suggesting that IGF1 is associated with the pivotal precursor to colorectal cancer.
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Iron homeostasis and distal colorectal adenoma risk in the prostate, lung, colorectal, and ovarian cancer screening trial.
Cancer Prev Res (Phila)
PUBLISHED: 06-17-2011
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Red meat consumption has been positively associated with colorectal cancer; however, the biological mechanism underlying this relationship is not understood. Red meat is a major source of iron, which may play a role in colorectal carcinogenesis via increased crypt cell proliferation, cytotoxicity, and endogenous N-nitrosation. In a nested case-control study within the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, we prospectively evaluated multiple iron exposure parameters, including dietary intake and serum measures of iron, ferritin, transferrin, total iron binding capacity (TIBC), and unsaturated iron binding capacity (UIBC) in relation to incident colorectal adenoma in 356 cases and 396 matched polyp-free controls. We also investigated variation in eight key genes involved in iron homeostasis in relation to colorectal adenoma in an additional series totaling 1,126 cases and 1,173 matched controls. We observed a positive association between red meat intake and colorectal adenoma [OR comparing extreme quartiles (OR(q4-q1)) = 1.59, 95% CI = 1.02-2.49, P(trend) = 0.03]. Serum TIBC and UIBC were inversely associated with colorectal adenoma (OR(q4-q1) = 0.57, 95% CI = 0.37-0.88, P(trend) = 0.03; and OR(q4-q1) = 0.62, 95% CI = 0.40-0.95, P(trend) = 0.04, respectively). Colorectal adenoma was not associated with serum ferritin, iron, or transferrin saturation or with polymorphisms in genes involved in iron homeostasis. Serum TIBC and UIBC, parameters that have a reciprocal relationship with overall iron load, were inversely related to colorectal adenoma, suggesting that individuals with lower iron status have a reduced risk of developing colorectal adenoma.
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A comprehensive candidate gene approach identifies genetic variation associated with osteosarcoma.
BMC Cancer
PUBLISHED: 05-29-2011
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Osteosarcoma (OS) is a bone malignancy which occurs primarily in adolescents. Since it occurs during a period of rapid growth, genes important in bone formation and growth are plausible modifiers of risk. Genes involved in DNA repair and ribosomal function may contribute to OS pathogenesis, because they maintain the integrity of critical cellular processes. We evaluated these hypotheses in an OS association study of genes from growth/hormone, bone formation, DNA repair, and ribosomal pathways.
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Large-scale fine mapping of the HNF1B locus and prostate cancer risk.
Hum. Mol. Genet.
PUBLISHED: 05-16-2011
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Previous genome-wide association studies have identified two independent variants in HNF1B as susceptibility loci for prostate cancer risk. To fine-map common genetic variation in this region, we genotyped 79 single nucleotide polymorphisms (SNPs) in the 17q12 region harboring HNF1B in 10 272 prostate cancer cases and 9123 controls of European ancestry from 10 case-control studies as part of the Cancer Genetic Markers of Susceptibility (CGEMS) initiative. Ten SNPs were significantly related to prostate cancer risk at a genome-wide significance level of P < 5 × 10(-8) with the most significant association with rs4430796 (P = 1.62 × 10(-24)). However, risk within this first locus was not entirely explained by rs4430796. Although modestly correlated (r(2)= 0.64), rs7405696 was also associated with risk (P = 9.35 × 10(-23)) even after adjustment for rs4430769 (P = 0.007). As expected, rs11649743 was related to prostate cancer risk (P = 3.54 × 10(-8)); however, the association within this second locus was stronger for rs4794758 (P = 4.95 × 10(-10)), which explained all of the risk observed with rs11649743 when both SNPs were included in the same model (P = 0.32 for rs11649743; P = 0.002 for rs4794758). Sequential conditional analyses indicated that five SNPs (rs4430796, rs7405696, rs4794758, rs1016990 and rs3094509) together comprise the best model for risk in this region. This study demonstrates a complex relationship between variants in the HNF1B region and prostate cancer risk. Further studies are needed to investigate the biological basis of the association of variants in 17q12 with prostate cancer.
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Diet and the risk of head and neck cancer: a pooled analysis in the INHANCE consortium.
Cancer Causes Control
PUBLISHED: 05-11-2011
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We investigated the association between diet and head and neck cancer (HNC) risk using data from the International Head and Neck Cancer Epidemiology (INHANCE) consortium. The INHANCE pooled data included 22 case-control studies with 14,520 cases and 22,737 controls. Center-specific quartiles among the controls were used for food groups, and frequencies per week were used for single food items. A dietary pattern score combining high fruit and vegetable intake and low red meat intake was created. Odds ratios (OR) and 95% confidence intervals (CI) for the dietary items on the risk of HNC were estimated with a two-stage random-effects logistic regression model. An inverse association was observed for higher-frequency intake of fruit (4th vs. 1st quartile OR = 0.52, 95% CI = 0.43-0.62, p (trend) < 0.01) and vegetables (OR = 0.66, 95% CI = 0.49-0.90, p (trend) = 0.01). Intake of red meat (OR = 1.40, 95% CI = 1.13-1.74, p (trend) = 0.13) and processed meat (OR = 1.37, 95% CI = 1.14-1.65, p (trend) < 0.01) was positively associated with HNC risk. Higher dietary pattern scores, reflecting high fruit/vegetable and low red meat intake, were associated with reduced HNC risk (per score increment OR = 0.90, 95% CI = 0.84-0.97).
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Fine mapping of a region of chromosome 11q13 reveals multiple independent loci associated with risk of prostate cancer.
Hum. Mol. Genet.
PUBLISHED: 04-29-2011
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Genome-wide association studies have identified prostate cancer susceptibility alleles on chromosome 11q13. As part of the Cancer Genetic Markers of Susceptibility (CGEMS) Initiative, the region flanking the most significant marker, rs10896449, was fine mapped in 10 272 cases and 9123 controls of European origin (10 studies) using 120 common single nucleotide polymorphisms (SNPs) selected by a two-staged tagging strategy using HapMap SNPs. Single-locus analysis identified 18 SNPs below genome-wide significance (P< 10(-8)) with rs10896449 the most significant (P= 7.94 × 10(-19)). Multi-locus models that included significant SNPs sequentially identified a second association at rs12793759 [odds ratio (OR) = 1.14, P= 4.76 × 10(-5), adjusted P= 0.004] that is independent of rs10896449 and remained significant after adjustment for multiple testing within the region. rs10896438, a proxy of previously reported rs12418451 (r(2)= 0.96), independent of both rs10896449 and rs12793759 was detected (OR = 1.07, P= 5.92 × 10(-3), adjusted P= 0.054). Our observation of a recombination hotspot that separates rs10896438 from rs10896449 and rs12793759, and low linkage disequilibrium (rs10896449-rs12793759, r(2)= 0.17; rs10896449-rs10896438, r(2)= 0.10; rs12793759-rs10896438, r(2)= 0.12) corroborate our finding of three independent signals. By analysis of tagged SNPs across ?123 kb using next generation sequencing of 63 controls of European origin, 1000 Genome and HapMap data, we observed multiple surrogates for the three independent signals marked by rs10896449 (n= 31), rs10896438 (n= 24) and rs12793759 (n= 8). Our results indicate that a complex architecture underlying the common variants contributing to prostate cancer risk at 11q13. We estimate that at least 63 common variants should be considered in future studies designed to investigate the biological basis of the multiple association signals.
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Meta-analysis of new genome-wide association studies of colorectal cancer risk.
Hum. Genet.
PUBLISHED: 04-18-2011
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Colorectal cancer is the second leading cause of cancer death in developed countries. Genome-wide association studies (GWAS) have successfully identified novel susceptibility loci for colorectal cancer. To follow up on these findings, and try to identify novel colorectal cancer susceptibility loci, we present results for GWAS of colorectal cancer (2,906 cases, 3,416 controls) that have not previously published main associations. Specifically, we calculated odds ratios and 95% confidence intervals using log-additive models for each study. In order to improve our power to detect novel colorectal cancer susceptibility loci, we performed a meta-analysis combining the results across studies. We selected the most statistically significant single nucleotide polymorphisms (SNPs) for replication using ten independent studies (8,161 cases and 9,101 controls). We again used a meta-analysis to summarize results for the replication studies alone, and for a combined analysis of GWAS and replication studies. We measured ten SNPs previously identified in colorectal cancer susceptibility loci and found eight to be associated with colorectal cancer (p value range 0.02 to 1.8 × 10(-8)). When we excluded studies that have previously published on these SNPs, five SNPs remained significant at p < 0.05 in the combined analysis. No novel susceptibility loci were significant in the replication study after adjustment for multiple testing, and none reached genome-wide significance from a combined analysis of GWAS and replication. We observed marginally significant evidence for a second independent SNP in the BMP2 region at chromosomal location 20p12 (rs4813802; replication p value 0.03; combined p value 7.3 × 10(-5)). In a region on 5p33.15, which includes the coding regions of the TERT-CLPTM1L genes and has been identified in GWAS to be associated with susceptibility to at least seven other cancers, we observed a marginally significant association with rs2853668 (replication p value 0.03; combined p value 1.9 × 10(-4)). Our study suggests a complex nature of the contribution of common genetic variants to risk for colorectal cancer.
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DNA repair gene polymorphisms and tobacco smoking in the risk for colorectal adenomas.
Carcinogenesis
PUBLISHED: 04-18-2011
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DNA damage is thought to play a critical role in the development of colorectal adenoma. Variation in DNA repair genes may alter their capacity to correct endogenous and exogenous DNA damage. We explored the association between common single-nucleotide polymorphisms (SNPs) in DNA repair genes and adenoma risk with a case-control study nested in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. A total of 1338 left sided, advanced colorectal adenoma cases and 1503 matched controls free of left-sided polyps were included in the study. Using DNA extracted from blood, 3144 tag SNPs in 149 DNA repair genes were successfully genotyped. Among Caucasians, 30 SNPs were associated with adenoma risk at P < 0.01, with four SNPs remaining significant after gene-based adjustment for multiple testing. The most significant finding was for a non-synonymous SNP (rs9350) in Exonuclease-1 (EXO1) [odds ratio (OR) = 1.30, 95% confidence interval (CI) = 1.11-1.51, P = 0.001)], which was predicted to be damaging using bioinformatics methods. However, the association was limited to smokers with a strong risk for current smokers (OR = 2.15, 95% CI = 1.27-3.65) and an intermediate risk for former smokers (OR = 1.45, 95% CI = 1.14-1.82) and no association for never smokers (OR = 0.98, 95% CI = 0.76-1.25) (P(interaction) = 0.002). Among the top findings, an SNP (rs17503908) in ataxia telangiectasia mutated (ATM) was inversely related to adenoma risk (OR = 0.75, 95% CI = 0.63-0.91). The association was restricted to never smokers (OR = 0.55, 95% CI = 0.40-0.76) with no increased risk observed among smokers (OR = 0.89, 95% CI = 0.70-1.13) (P(interaction) = 0.006). This large comprehensive study, which evaluated all presently known DNA repair genes, suggests that polymorphisms in EXO1 and ATM may be associated with risk for advanced colorectal adenoma with the associations modified by tobacco-smoking status.
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Genome-wide association study of relative telomere length.
PLoS ONE
PUBLISHED: 04-11-2011
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Telomere function is essential to maintaining the physical integrity of linear chromosomes and healthy human aging. The probability of forming proper telomere structures depends on the length of the telomeric DNA tract. We attempted to identify common genetic variants associated with log relative telomere length using genome-wide genotyping data on 3,554 individuals from the Nurses Health Study and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial that took part in the National Cancer Institute Cancer Genetic Markers of Susceptibility initiative for breast and prostate cancer. After genotyping 64 independent SNPs selected for replication in additional Nurses Health Study and Womens Genome Health Study participants, we did not identify genome-wide significant loci; however, we replicated the inverse association of log relative telomere length with the minor allele variant [C] of rs16847897 at the TERC locus (per allele ??=?-0.03, P?=?0.003) identified by a previous genome-wide association study. We did not find evidence for an association with variants at the OBFC1 locus or other loci reported to be associated with telomere length. With this sample size we had >80% power to detect ? estimates as small as ±0.10 for SNPs with minor allele frequencies of ?0.15 at genome-wide significance. However, power is greatly reduced for ? estimates smaller than ±0.10, such as those for variants at the TERC locus. In general, common genetic variants associated with telomere length homeostasis have been difficult to detect. Potential biological and technical issues are discussed.
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HIV and other sexually transmitted infections in a cohort of women involved in high-risk sexual behavior in Kampala, Uganda.
Sex Transm Dis
PUBLISHED: 04-01-2011
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Uganda has long been successful in controlling the HIV epidemic; however, there is evidence that HIV prevalence and incidence are increasing again. Data on the HIV/STI epidemic among sex workers are so far lacking from Uganda. This paper describes the baseline epidemiology of HIV/STI in a newly established cohort of women involved in high-risk sexual behavior in Kampala, Uganda.
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The association between inflammation-related genes and serum androgen levels in men: the prostate, lung, colorectal, and ovarian study.
Prostate
PUBLISHED: 03-28-2011
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Androgens and inflammation have been implicated in the etiology of several cancers, including prostate cancer. Serum androgens have been shown to correlate with markers of inflammation and expression of inflammation-related genes.
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Sequence Variants and the Risk of Head and Neck Cancer: Pooled Analysis in the INHANCE Consortium.
Front Oncol
PUBLISHED: 03-20-2011
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Previous molecular epidemiological studies on head and neck cancer have examined various single nucleotide polymorphisms (SNPs), but there are very few documented associations. In the International head and neck cancer epidemiology (INHANCE) consortium, we evaluated associations between SNPs in the metabolism, cell cycle, and DNA repair pathways and the risk of head and neck cancer. We analyzed individual-level pooled data from 14 European, North American, Central American, and Asia case-control studies (5,915 head and neck cancer cases and 10,644 controls) participating in the INHANCE consortium. Unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for SNP effects, adjusting for age, sex, race, and country. We observed an association between head and neck cancer risk and MGMT Leu84Phe heterozygotes (OR?=?0.79, 95% CI?=?0.68-0.93), XRCC1 Arg194Trp homozygotes Arg/Arg (OR?=?2.3, 95% CI?=?1.1-4.7), ADH1B Arg48His homozygotes Arg/Arg (OR?=?2.7, 95% CI?=?1.9-4.0), ADH1C Ile350Val homozygotes Ile/Ile (OR?=?1.2, 95% CI?=?1.1-1.4), and the GSTM1 null genotype (OR?=?1.1, 95% CI?=?1.0-1.2). Among these results, MGMT Leu84Phe, ADH1B Arg48His, ADH1C Ile350Arg, and the GSTM1 null genotype had fairly low false positive report probabilities (<20%). We observed associations between ADH1B Arg48His, ADH1C Ile350Arg, and GSTM1 null genotype and head and neck cancer risk. No functional study currently supports the observed association for MGMT Leu84Phe, and the association with XRCC1 Arg194Trp may be a chance finding.
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Oral microbiome profiles: 16S rRNA pyrosequencing and microarray assay comparison.
PLoS ONE
PUBLISHED: 03-07-2011
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The human oral microbiome is potentially related to diverse health conditions and high-throughput technology provides the possibility of surveying microbial community structure at high resolution. We compared two oral microbiome survey methods: broad-based microbiome identification by 16S rRNA gene sequencing and targeted characterization of microbes by custom DNA microarray.
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Seven prostate cancer susceptibility loci identified by a multi-stage genome-wide association study.
Zsofia Kote-Jarai, Ali Amin Al Olama, Graham G Giles, Gianluca Severi, Johanna Schleutker, Maren Weischer, Daniele Campa, Elio Riboli, Tim Key, Henrik Grönberg, David J Hunter, Peter Kraft, Michael J Thun, Sue Ingles, Stephen Chanock, Demetrius Albanes, Richard B Hayes, David E Neal, Freddie C Hamdy, Jenny L Donovan, Paul Pharoah, Fredrick Schumacher, Brian E Henderson, Janet L Stanford, Elaine A Ostrander, Karina Dalsgaard Sorensen, Thilo Dörk, Gerald Andriole, Joanne L Dickinson, Cezary Cybulski, Jan Lubiński, Amanda Spurdle, Judith A Clements, Suzanne Chambers, Joanne Aitken, R A Frank Gardiner, Stephen N Thibodeau, Dan Schaid, Esther M John, Christiane Maier, Walther Vogel, Kathleen A Cooney, Jong Y Park, Lisa Cannon-Albright, Hermann Brenner, Tomonori Habuchi, Hong-Wei Zhang, Yong-Jie Lu, Radka Kaneva, Ken Muir, Sara Benlloch, Daniel A Leongamornlert, Edward J Saunders, Malgorzata Tymrakiewicz, Nadiya Mahmud, Michelle Guy, Lynne T O'Brien, Rosemary A Wilkinson, Amanda L Hall, Emma J Sawyer, Tokhir Dadaev, Jonathan Morrison, David P Dearnaley, Alan Horwich, Robert A Huddart, Vincent S Khoo, Christopher C Parker, Nicholas van As, Christopher J Woodhouse, Alan Thompson, Tim Christmas, Chris Ogden, Colin S Cooper, Aritaya Lophatonanon, Melissa C Southey, John L Hopper, Dallas R English, Tiina Wahlfors, Teuvo L J Tammela, Peter Klarskov, Børge G Nordestgaard, M Andreas Røder, Anne Tybjærg-Hansen, Stig E Bojesen, Ruth Travis, Federico Canzian, Rudolf Kaaks, Fredrik Wiklund, Markus Aly, Sara Lindstrom, W Ryan Diver, Susan Gapstur, Mariana C Stern, Román Corral, Jarmo Virtamo, Angela Cox, Christopher A Haiman, Loic Le Marchand, Liesel Fitzgerald, Suzanne Kolb, Erika M Kwon, Danielle M Karyadi, Torben Falck Orntoft, Michael Borre, Andreas Meyer, Jürgen Serth, Meredith Yeager, Sonja I Berndt, James R Marthick, Briony Patterson, Dominika Wokolorczyk, Jyotsna Batra, Felicity Lose, Shannon K McDonnell, Amit D Joshi, Ahva Shahabi, Antje E Rinckleb, Ana Ray, Thomas A Sellers, Hui-Yi Lin, Robert A Stephenson, James Farnham, Heiko Muller, Dietrich Rothenbacher, Norihiko Tsuchiya, Shintaro Narita, Guang-Wen Cao, Chavdar Slavov, Vanio Mitev, Douglas F Easton, Rosalind A Eeles, .
Nat. Genet.
PUBLISHED: 03-03-2011
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Prostate cancer (PrCa) is the most frequently diagnosed male cancer in developed countries. We conducted a multi-stage genome-wide association study for PrCa and previously reported the results of the first two stages, which identified 16 PrCa susceptibility loci. We report here the results of stage 3, in which we evaluated 1,536 SNPs in 4,574 individuals with prostate cancer (cases) and 4,164 controls. We followed up ten new association signals through genotyping in 51,311 samples in 30 studies from the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium. In addition to replicating previously reported loci, we identified seven new prostate cancer susceptibility loci on chromosomes 2p11, 3q23, 3q26, 5p12, 6p21, 12q13 and Xq12 (P = 4.0 × 10(-8) to P = 2.7 × 10(-24)). We also identified a SNP in TERT more strongly associated with PrCa than that previously reported. More than 40 PrCa susceptibility loci, explaining ?25% of the familial risk in this disease, have now been identified.
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Nonsteroidal antiinflammatory drugs and bladder cancer: a pooled analysis.
Am. J. Epidemiol.
PUBLISHED: 03-02-2011
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Case-control studies have shown that regular use of nonsteroidal antiinflammatory drugs (NSAIDs) decreases bladder cancer risk, but few cohort studies have evaluated this association. The authors investigated NSAID use and bladder cancer in 3 large prospective studies (NIH-AARP Diet and Health Study; Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial; and U.S. Radiologic Technologists Study). Frequency of aspirin and nonaspirin NSAID use 1 year prior to baseline was ascertained using self-administered questionnaires. Study-specific hazard ratios and 95% confidence intervals were estimated using Cox regression models and were combined using a fixed-effects meta-analytic model. Data from all studies were aggregated, and aggregated hazard ratios were estimated. The analysis included 508,842 individuals, with 2,489 incident cases of bladder cancer. A reduction in risk was observed for individuals who reported regular use (>2 times/week) of nonaspirin NSAIDs compared with those who reported no use (hazard ratio (HR) = 0.92, 95% confidence interval (CI): 0.81, 1.04). The risk reduction was limited to nonsmokers (HR = 0.58, 95% CI: 0.41, 0.83) (P(trend) = 0.008) (P(interaction) = 0.02). No association was observed between regular aspirin use and bladder cancer risk (HR = 1.04, 95% CI: 0.94, 1.15). Results suggest that nonaspirin NSAIDs, but not aspirin, are associated with a reduction in risk of bladder cancer, particularly for nonsmokers.
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