JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Ionizing Radiation Sensitizes Breast Cancer Cells to Bcl-2 Inhibitor, ABT-737, through Regulating Mcl-1.
Radiat. Res.
PUBLISHED: 11-20-2014
Show Abstract
Hide Abstract
Breast-conserving surgery followed by radiation therapy has become the standard of care for early stage breast cancer. However, there are some patients that develop a local failure. We have previously shown that Bcl-2 overexpression was associated with an increased risk of local recurrence in patients with early stage breast cancer. The purpose of this study was to explore an approach to overcome radiation resistance by targeting pro-survival Bcl-2 family proteins in breast cancer cells. The breast cancer cell lines MCF-7, ZR-75-1 and MDA-MB231 were used in this study. siRNAs were employed to silence myeloid cell leukemia 1 (Mcl-1). A small molecule inhibitor of Bcl-2, ABT-737, was used to target anti-apoptotic Bcl-2 family proteins. Apoptosis was identified by FITC Annexin V, PI staining and Western blot analysis. The sensitivity to ionizing radiation and ABT-737 were measured by clonogenic assays. The effect of radiation and ABT-737 was also tested in a MCF-7 xenograft mouse model. Our data demonstrate that the combination of ABT-737 and radiation-induced apoptosis had an inhibitory effect on breast cancer cell proliferation. However, treatment with ABT-737 resulted in elevated Mcl-1 in breast cancer cell lines. Targeting Mcl-1 by siRNA sensitized MCF-7 cells to ABT-737. We revealed that radiation blunted Mcl-1 elevation induced by ABT-737, and that radiation downregulated Mcl-1 by promoting its degradation. Our results indicate that radiation and ABT-737 exert a synergistic effect on breast cancer cell lines through downregulating Mcl-1 and activating the bak-apoptotic pathway. These results support the combination of radiation and pro-survival Bcl-2 family inhibitor as a potential novel therapeutic strategy in the local-regional management of breast cancer.
Related JoVE Video
The Spleen Tyrosine Kinase (syk) Regulates Alzheimer's A? Production and Tau Hyperphosphorylation.
J. Biol. Chem.
PUBLISHED: 10-22-2014
Show Abstract
Hide Abstract
We have previously shown that the L-type calcium channel (LCC) antagonist nilvadipine reduces brain A? accumulation by affecting both A? production and A? clearance across the blood-brain barrier (BBB). Nilvadipine consists of a mixture of two enantiomers, (+)-nilvadipine and (-)-nilvadipine, in equal proportion. (+)-nilvadipine is the active enantiomer responsible for the inhibition of LCC whereas (-)-nilvadipine is considered inactive. Both nilvadipine enantiomers inhibit A? production and improve the clearance of A? across the BBB showing that these effects are not related to LCC inhibition. In addition, treatment of P301S mutant human Tau transgenic mice (Tg Tau P301S) with (-)-nilvadipine reduces tau hyperphosphorylation at several AD pertinent epitopes. A search for the mechanism of action of (-)-nilvadipine revealed that this compound inhibits the spleen tyrosine kinase (syk). We further validated syk as a target regulating A? by showing that pharmacological inhibition of syk or downregulation of syk expression reduces A? production and increases the clearance of A? across the BBB mimicking (-)-nilvadipine effects. Moreover, treatment of transgenic mice overexpressing A? and Tg Tau P301S mice with a selective syk inhibitor respectively decreased brain A? accumulation and tau hyperphosphorylation at multiple AD relevant epitopes. We show that syk inhibition induces an increased phosphorylation of the inhibitory Ser9 residue of glycogen synthase kinase-3?, a primary tau kinase involved in tau phosphorylation, by activating protein kinase A, providing a mechanism explaining the reduction of tau phosphorylation at GSK3? dependent epitopes following syk inhibition. Altogether our data highlight syk as a promising target for preventing both A? accumulation and tau hyperphosphorylation in AD.
Related JoVE Video
Intake of energy-dense foods, fast foods, sugary drinks, and breast cancer risk in african american and European american women.
Nutr Cancer
PUBLISHED: 09-29-2014
Show Abstract
Hide Abstract
Limiting energy-dense foods, fast foods, and sugary drinks that promote weight gain is a cancer prevention recommendation, but no studies have evaluated intake in relation to breast cancer risk in African American (AA) women. In a case-control study with 1692 AA women (803 cases and 889 controls) and 1456 European American (EA) women (755 cases and 701 controls), odds ratios (OR) and 95% confidence intervals (CI) for risk were computed, stratifying for menopausal and estrogen receptor (ER) status. Among postmenopausal EA women, breast cancer risk was associated with frequent consumption of energy-dense foods (OR = 2.95; 95% CI: 1.66-5.22), fast foods (OR = 2.35; 95% CI: 1.38-4.00), and sugary drinks (OR = 2.05; 95% CI: 1.13-3.70). Elevated risk of ER+ tumors in EA women was associated with energy-dense (OR = 1.75; 95% CI: 1.14-2.69) and fast foods (OR = 1.84; 95% CI: 1.22-2.77). Among AA women, frequent fast food consumption was related to premenopausal breast cancer risk (OR = 1.97; 95% CI: 1.13-3.43), and with ER+ tumors. Energy adjustment attenuated risk estimates in AA women, while strengthening them among EA women. Frequent consumption of energy-dense and fast foods that have poor nutritive value appeared to increase breast cancer risk in AA and EA women, with differences by menopausal status and ER status.
Related JoVE Video
MicroRNA-155 attenuates activation of hepatic stellate cell by simultaneously preventing EMT process and ERK1 signalling pathway.
Liver Int.
PUBLISHED: 08-20-2014
Show Abstract
Hide Abstract
Epithelial-mesenchymal transition (EMT) process and extracellular signal-regulated kinase 1 (ERK1) signalling pathway play pivotal roles in hepatic stellate cell (HSC) activation, which is associated with the altered expression patterns of microRNAs (miRNAs). miR-155 is considered a typical multifunctional miRNA to regulate many biological processes. However, little attention has been given to the contributions of miR-155 to simultaneous regulation of EMT process and ERK1 pathway during HSC activation.
Related JoVE Video
A prospective study of biomarker-guided chemotherapy in patients with non-small cell lung cancer.
Cancer Chemother. Pharmacol.
PUBLISHED: 08-14-2014
Show Abstract
Hide Abstract
To assess the therapeutic value of biomarker-guided chemotherapy in patients with advanced non-small cell lung cancer (NSCLC).
Related JoVE Video
A signaling pathway consisting of miR-551b, catalase and MUC1 contributes to acquired apoptosis resistance and chemoresistance.
Carcinogenesis
PUBLISHED: 08-01-2014
Show Abstract
Hide Abstract
Acquired chemoresistance is a major challenge in cancer therapy. While the oncoprotein Mucin-1 (MUC1) performs multiple roles in the development of diverse human tumors, whether MUC1 is involved in acquired chemoresistance has not been determined. Using an acquired chemoresistance lung cancer cell model, we show that MUC1 expression was substantially increased in cells with acquired apoptosis resistance (AR). Knockdown of MUC1 expression effectively increased the sensitivity of these cells to the apoptotic cytotoxicity of anticancer therapeutics, suggesting that MUC1 contributes to acquired chemoresistance. Decreased catalase expression and increased cellular reactive oxygen species (ROS) accumulation were found to be associated with MUC1 overexpression. Scavenging ROS with butylated hydroxyanisole or supplying exogenous catalase dramatically suppressed MUC1 expression through destabilizing MUC1 protein, suggesting that reduced catalase expression mediated ROS accumulation is accounted for MUC1 overexpression. Further, we found that increased miR-551b expression in the AR cells inhibited the expression of catalase and potentiated ROS accumulation and MUC1 expression. Finally, by manipulating MUC1 expression, we found that MUC1 promotes EGFR-mediated activation of the cell survival cascade involving Akt/c-FLIP/COX-2 in order to protect cancer cells from responding to anticancer agents. Thus, our results establish a pathway consisting of miR-551b/catalase/ROS that results in MUC1 overexpression, and intervention against this pathway could be exploited to overcome acquired chemoresistance.
Related JoVE Video
Fifteen-year survival outcomes following primary androgen-deprivation therapy for localized prostate cancer.
JAMA Intern Med
PUBLISHED: 07-16-2014
Show Abstract
Hide Abstract
One in 6 American men will be diagnosed as having prostate cancer during their lifetime. Although there are no data to support the use of primary androgen-deprivation therapy (ADT) for early-stage prostate cancer, primary ADT has been widely used for localized prostate cancer, especially among older patients.
Related JoVE Video
Concordance in cervical HPV detection between hybrid capture 2 and HPV GenoArray tests.
Asian Pac. J. Cancer Prev.
PUBLISHED: 06-28-2014
Show Abstract
Hide Abstract
HPV type-specific detection may promote cervical screening program and vaccination development worldwide. We conduct a study comparing HPV Hybrid capture II (HC II) Test and Hybribio GenoArray test, a newly developed HPV type-specific assay, in patients with cervical epithelial neoplasm. Results showed a good concordance in cervical HPV detection between two tests (kappa value 0.80, p<0.05, McNemar test). Our study may promote utilization of type-specific HPV detection that is helpful for cervical cancer screening and vaccination.
Related JoVE Video
Association of the XRCC1 c.1178G>A genetic polymorphism with lung cancer risk in Chinese.
Asian Pac. J. Cancer Prev.
PUBLISHED: 06-18-2014
Show Abstract
Hide Abstract
The X-ray repair cross-complementing group 1 protein (XRCC1) plays important roles in the DNA base excision repair pathway which may influence the development of lung cancer. This study aimed to evaluate the potential association of the XRCC1 c.1178G>A genetic polymorphism with lung cancer risk. The created restriction site-polymerase chain reaction (CRS-PCR) and DNA sequencing methods were utilized to evaluate the XRCC1 c.1178G>A genetic polymorphism among 376 lung cancer patients and 379 controls. Associations between the genetic polymorphism and lung cancer risk were determined with an unconditional logistic regression model. Our data suggested that the distribution of allele and genotype in lung cancer patients was significantly different from that of controls. The XRCC1 c.1178G>A genetic polymorphism was associated with an increased risk of lung cancer (AA vs GG: OR=2.91, 95%CI 1.70-4.98, p<0.001; A vs G: OR=1.52, 95%CI 1.22-1.90, p<0.001). The allele A and genotype AA may contribute to risk of lung cancer. These preliminary results suggested that the XRCC1 c.1178G>A genetic polymorphism is statistically associated with lung cancer risk in the Chinese population.
Related JoVE Video
Poly(I:C) treatment leads to interferon-dependent clearance of hepatitis B virus in a hydrodynamic injection mouse model.
J. Virol.
PUBLISHED: 06-11-2014
Show Abstract
Hide Abstract
We have previously shown that poly(I:C) activates murine hepatic cells to produce interferon (IFN) and suppresses hepatitis B virus (HBV) replication in vitro. Therefore, we addressed whether poly(I:C) is able to induce the clearance of HBV in vivo. The chronic HBV replication mouse model was established by the hydrodynamic injection (HI) of pAAV-HBV1.2 into the tail veins of wild-type and IFN-?/?R-, IFN-?-, and CXCR3-deficient C57BL/6 mice. Fourteen days post-HI of pAAV-HBV1.2, mice were administered poly(I:C) by intraperitoneal injection, intramuscular injection, or HI. Only treatment of poly(I:C) by HI led to HBV clearance in wild-type C57BL/6 mice. Serum HBsAg disappeared within 40 days postinfection (dpi) in mice that received poly(I:C) by HI, and this was accompanied by the appearance of anti-HBs antibodies. HBV-specific T-cell and antibody responses were significantly enhanced by HI of poly(I:C). HBV replication intermediates and HBcAg-positive hepatocytes were eliminated in the liver. HI of poly(I:C) induced the production of IFNs in mice and enhanced the levels of cytokines, IFN-stimulated genes, and T-cell markers in the liver. Importantly, poly(I:C)-induced HBV clearance was impaired in IFN-?/?R-, IFN-?-, and CXCR3-deficient mice, indicating that the induction of type I IFN and the stimulation and recruitment of T cells into the liver are essential for HBV clearance in this model. Taken together, the application of poly(I:C) by HI into the liver enhances innate and adaptive immune responses and leads to HBV clearance in an HBV mouse model, implicating the potential of intrahepatic Toll-like receptor 3 (TLR3) activation for the treatment of chronic hepatitis B patients.
Related JoVE Video
Reversal of multidrug resistance in vitro and in vivo by 5-N-formylardeemin, a new ardeemin derivative.
Apoptosis
PUBLISHED: 05-27-2014
Show Abstract
Hide Abstract
Because multidrug resistance (MDR) is a serious impediment to the use of chemotherapy in treating cancer patients, great efforts have been made to search for effective MDR-reversing agents. We have developed a brand new synthetic ardeemin derivative, 5-N-formylardeemin, and investigated the activity of which in reversing MDR in MDR cancer cell lines derived from human breast cancer (MCF-7-R) or lung cancer (A549-R). 5-N-formylardeemin strongly enhanced the anti-cancer efficacy of doxorubicin, vincristine through potentiation of apoptosis in both MCF-7-R and A549-R at relatively noncytotoxic concentrations in vitro. Mechanistic studies showed that 5-N-formylardeemin inhibited the expression of MDR-1 (P-gp) and increased the intracellular accumulation of cytotoxic drugs in the MDR cells, suggesting that 5-N-formylardeemin reverses MDR activities through inhibiting MDR-1 expression. Interestingly, 5-N-formylardeemin also sensitized the parent wild-type cancer cells toward these chemotherapeutic agents to various extents. Importantly, in vivo studies demonstrated that 5-N-formylardeemin significantly improved the therapeutic effects of doxorubicin in nude mice bearing A549-R xenografts, which was associated with reduced expression of MDR-1 protein level and increased apoptosis in tumor tissues. These results underscore 5-N-formylardeemin as a potential sensitizer for chemotherapy against multidrug resistant cancers.
Related JoVE Video
Improvement of a sample preparation method assisted by sodium deoxycholate for mass-spectrometry-based shotgun membrane proteomics†.
J Sep Sci
PUBLISHED: 05-26-2014
Show Abstract
Hide Abstract
In current shotgun-proteomics-based biological discovery, the identification of membrane proteins is a challenge. This is especially true for integral membrane proteins due to their highly hydrophobic nature and low abundance. Thus, much effort has been directed at sample preparation strategies such as use of detergents, chaotropes, and organic solvents. We previously described a sample preparation method for shotgun membrane proteomics, the sodium deoxycholate assisted method, which cleverly circumvents many of the challenges associated with traditional sample preparation methods. However, the method is associated with significant sample loss due to the slightly weaker extraction/solubilization ability of sodium deoxycholate when it is used at relatively low concentrations such as 1%. Hence, we present an enhanced sodium deoxycholate sample preparation strategy that first uses a high concentration of sodium deoxycholate (5%) to lyse membranes and extract/solubilize hydrophobic membrane proteins, and then dilutes the detergent to 1% for a more efficient digestion. We then applied the improved method to shotgun analysis of proteins from rat liver membrane enriched fraction. Compared with other representative sample preparation strategies including our previous sodium deoxycholate assisted method, the enhanced sodium deoxycholate method exhibited superior sensitivity, coverage, and reliability for the identification of membrane proteins particularly those with high hydrophobicity and/or multiple transmembrane domains.
Related JoVE Video
Acrolein-exposed normal human lung fibroblasts in vitro: cellular senescence, enhanced telomere erosion, and degradation of werner's syndrome protein.
Environ. Health Perspect.
PUBLISHED: 04-15-2014
Show Abstract
Hide Abstract
Acrolein is a ubiquitous environmental hazard to human health. Acrolein has been reported to activate the DNA damage response and induce apoptosis. However, little is known about the effects of acrolein on cellular senescence.
Related JoVE Video
Retaining MKP1 expression and attenuating JNK-mediated apoptosis by RIP1 for cisplatin resistance through miR-940 inhibition.
Oncotarget
PUBLISHED: 03-29-2014
Show Abstract
Hide Abstract
The elucidation of chemoresistance mechanisms is important to improve cancer patient survival. In this report, we investigated the role and mechanism through which receptor-interacting protein 1 (RIP1), a mediator in cell survival and death signaling, participates in cancer's response to chemotherapy. In lung cancer cells, knockdown of RIP1 substantially increased cisplatin-induced apoptotic cytotoxicity, which was associated with robust JNK activation. The expression of the JNK inactivating phosphatase, MKP1, was substantially reduced in RIP1 knockdown cells. Although MKP1 protein stability was not altered by RIP1 suppression, the synthesis rate of MKP1 was dramatically reduced in RIP1-suppressed cells. Furthermore, we found that the expression of miR-940 was substantially increased in RIP1 knockdown cells. Knockdown of miR-940 restored MKP1 expression and attenuated cisplatin-induced JNK activation and cytotoxicity. Importantly, ectopic expression of MKP1 effectively attenuated cisplatin-induced JNK activation and cytotoxicity. In addition, activation of the JNK upstream signaling kinase, MKK4, was also potentiated in RIP1 knockdown cells. Altogether, our results suggest that RIP1 contributes to cisplatin resistance by suppressing JNK activation that involves releasing miR-940-mediated inhibition of MKP1 and suppressing activation of MKK4. Intervention targeting the RIP1/miR-940/MKP1/JNK pathway may be used to sensitize platinum-based chemotherapy.
Related JoVE Video
FISH: fast and accurate diploid genotype imputation via segmental hidden Markov model.
Bioinformatics
PUBLISHED: 03-10-2014
Show Abstract
Hide Abstract
Fast and accurate genotype imputation is necessary for facilitating gene-mapping studies, especially with the ever increasing numbers of both common and rare variants generated by high-throughput-sequencing experiments. However, most of the existing imputation approaches suffer from either inaccurate results or heavy computational demand.
Related JoVE Video
Spectroscopic insights on imidazole substituted phthalocyanine photosensitizers: fluorescence properties, triplet state and singlet oxygen generation.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 02-19-2014
Show Abstract
Hide Abstract
Imidazole substituted metal phthalocyanine (Pc) complexes were synthesized. UV-vis absorption, steady state and time-resolved fluorescence, as well as laser flash photolysis were used to measure the photophysical and photosensitizing properties. All the imidazole-phthalocyanine conjugates show high ?T (quantum yield of excited triplet formation), high ?? (singlet oxygen formation yield, >0.50) and good fluorescence properties (quantum yield ?f>0.20 and lifetime ?f>3.0 ns). Compared to the unsubstituted Pc, both ?- and ?-imidazole substitutions result in the remarkable decrease in ?f and ?f, but the ?-substitution is stronger. The imidazole substitution, on the other hand, causes the increase of ?T, ?T, and ?? values. Magnesium phthalocyanine (MgPc) is more susceptible to the substitution than zinc phthalocyanine (ZnPc). The mechanism responsible for the result is suggested based on the involvement of intramolecular photoinduced electron transfer. The high ?? and appropriate fluorescence properties make the Pcs good candidate for PDT photosensitizers.
Related JoVE Video
Inhibitors of differentiation-1 promotes nitrosopyrrolidine-induced transformation of HPV 16-immortalized cervical epithelial cell.
Cancer Sci.
PUBLISHED: 02-13-2014
Show Abstract
Hide Abstract
Our previous study implied a correlation between inhibitors of differentiation-1 (Id-1) and cervical cancer development. However, how Id-1 contributes to cervical carcinogenesis is unknown. In the present study, we used an in vitro transformation model to investigate the role of Id-1 in the transformation of cervical cells. Human papillomavirus (HPV)-immortalized cervical epithelial cells (H8) were successfully transformed by exposure to the carcinogen N-nitrosopyrrolidine (NPYR). The expression of both Id-1 RNA and protein was significantly increased in transformed H8 cells, suggesting a possible role of Id-1 in cervical cell transformation. Ectopic expression of Id-1 in H8 cells potentiated NPYR-induced cell transformation. In contrast, silencing of Id-1 suppressed NPYR-induced H8 cell transformation. In addition, the expression of HPV E6 and E7 oncoproteins was upregulated while that of the tumor suppressors p53 and pRb was suppressed after H8 cell transformation. Our results suggest that Id-1 plays an oncogenic role in HPV-related cervical carcinogenesis, which sheds light on cervical cancer development mechanisms and implies that Id-1 is a potential target for cervical cancer prevention and therapy.
Related JoVE Video
Extension of a Cox proportional hazards cure model when cure information is partially known.
Biostatistics
PUBLISHED: 02-07-2014
Show Abstract
Hide Abstract
When there is evidence of long-term survivors, cure models are often used to model the survival curve. A cure model is a mixture model consisting of a cured fraction and an uncured fraction. Traditional cure models assume that the cured or uncured status in the censored set cannot be distinguished. But in many practices, some diagnostic procedures may provide partial information about the cured or uncured status relative to certain sensitivity and specificity. The traditional cure model does not take advantage of this additional information. Motivated by a clinical study on bone injury in pediatric patients, we propose a novel extension of a traditional Cox proportional hazards (PH) cure model that incorporates the additional information about the cured status. This extension can be applied when the latency part of the cure model is modeled by the Cox PH model. Extensive simulations demonstrated that the proposed extension provides more efficient and less biased estimations, and the higher efficiency and smaller bias is associated with higher sensitivity and specificity of diagnostic procedures. When the proposed extended Cox PH cure model was applied to the motivating example, there was a substantial improvement in the estimation.
Related JoVE Video
Activation of the glutamate receptor GRM1 enhances angiogenic signaling to drive melanoma progression.
Cancer Res.
PUBLISHED: 02-03-2014
Show Abstract
Hide Abstract
Glutamate-triggered signal transduction is thought to contribute widely to cancer pathogenesis. In melanoma, overexpression of the metabotropic glutamate receptor (GRM)-1 occurs frequently and its ectopic expression in melanocytes is sufficient for neoplastic transformation. Clinical evaluation of the GRM1 signaling inhibitor riluzole in patients with advanced melanoma has demonstrated tumor regressions that are associated with a suppression of the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathways. Together, these results prompted us to investigate the downstream consequences of GRM1 signaling and its disruption in more detail. We found that melanoma cells with enhanced GRM1 expression generated larger tumors in vivo marked by more abundant blood vessels. Media conditioned by these cells in vitro contained relatively higher concentrations of interleukin-8 and VEGF due to GRM1-mediated activation of the AKT-mTOR-HIF1 pathway. In clinical specimens from patients receiving riluzole, we confirmed an inhibition of MAPK and PI3K/AKT activation in posttreatment as compared with pretreatment tumor specimens, which exhibited a decreased density of blood vessels. Together, our results demonstrate that GRM1 activation triggers proangiogenic signaling in melanoma, offering a mechanistic rationale to design treatment strategies for the most suitable combinatorial use of GRM1 inhibitors in patients.
Related JoVE Video
Endovascular treatment of the extracranial carotid pseudoaneurysms resulting from stab penetrating injury using overlapping bare stents.
Vasc Endovascular Surg
PUBLISHED: 01-28-2014
Show Abstract
Hide Abstract
Injury pertaining to the common carotid artery may result in complete or partial arterial transection, pseudoaneurysms, or arteriovenous connections. Endovascular treatment option of the pseudoaneurysm has already been established with favorable success rate and minimal morbidity. Our purpose is to report one 18-year-old male patient having 2 traumatic pseudoaneurysms as a result of penetrating stab injury in the extracranial common carotid. The patient was successfully treated using 2 overlapping bare-metal stents. The 2 common carotid pseudoaneurysms had different degree inflow angles defined as the space between the lines indicating the direction of blood flow from the parent artery and through the aneurysmal neck to the dome. Computed tomography angiography was utilized to follow the evolution of the pseudoaneurysms until total occlusion was demonstrated. The treatment modality used in this report represents an alternative approach of the endovascular treatment for the extracranial carotid pseudoaneurysm.
Related JoVE Video
Receptor-interacting protein 1 increases chemoresistance by maintaining inhibitor of apoptosis protein levels and reducing reactive oxygen species through a microRNA-146a-mediated catalase pathway.
J. Biol. Chem.
PUBLISHED: 01-14-2014
Show Abstract
Hide Abstract
Although receptor-interacting protein 1 (RIP1) is well known as a key mediator in cell survival and death signaling, whether RIP1 directly contributes to chemotherapy response in cancer has not been determined. In this report, we found that, in human lung cancer cells, knockdown of RIP1 substantially increased cytotoxicity induced by the frontline anticancer therapeutic drug cisplatin, which has been associated with robust cellular reactive oxygen species (ROS) accumulation and enhanced apoptosis. Scavenging ROS dramatically protected RIP1 knockdown cells against cisplatin-induced cytotoxicity. Furthermore, we found that, in RIP1 knockdown cells, the expression of the hydrogen peroxide-reducing enzyme catalase was dramatically reduced, which was associated with increased miR-146a expression. Inhibition of microRNA-146a restored catalase expression, suppressed ROS induction, and protected against cytotoxicity in cisplatin-treated RIP1 knockdown cells, suggesting that RIP1 maintains catalase expression to restrain ROS levels in therapy response in cancer cells. Additionally, cisplatin significantly triggered the proteasomal degradation of cellular inhibitor of apoptosis protein 1 and 2 (c-IAP1 and c-IAP2), and X-linked inhibitor of apoptosis (XIAP) in a ROS-dependent manner, and in RIP1 knockdown cells, ectopic expression of c-IAP2 attenuated cisplatin-induced cytotoxicity. Thus, our results establish a chemoresistant role for RIP1 that maintains inhibitor of apoptosis protein (IAP) expression by release of microRNA-146a-mediated catalase suppression, where intervention within this pathway may be exploited for chemosensitization.
Related JoVE Video
Carbonic anhydrase 4 and crystallin ?-B immunoreactivity may distinguish benign from malignant thyroid nodules in patients with indeterminate thyroid cytology.
J. Surg. Res.
PUBLISHED: 01-08-2014
Show Abstract
Hide Abstract
Thyroid nodules are present in 19%-67% of the population and carry a 5%-10% risk of malignancy. Unfortunately, fine-needle aspiration biopsies are indeterminate in 20%-30% of patients, often necessitating thyroid surgery for diagnosis. Numerous DNA microarray studies including a recently commercialized molecular classifier have helped to better distinguish benign from malignant thyroid nodules. Unfortunately, these assays often require probes for >100 genes, are expensive, and only available at a few laboratories. We sought to validate these DNA microarray assays at the protein level and determine whether simple and widely available immunohistochemical biomarkers alone could distinguish benign from malignant thyroid nodules.
Related JoVE Video
A triple combination of atorvastatin, celecoxib and tipifarnib strongly inhibits pancreatic cancer cells and xenograft pancreatic tumors.
Int. J. Oncol.
PUBLISHED: 01-04-2014
Show Abstract
Hide Abstract
Because K-Ras mutation and cyclooxygenase-2 (COX-2) overexpression are hallmarks of majority of pancreatic cancer patients, an approach to inhibit the progression and growth of pancreatic cancer using the simultaneous administration of agents that inhibit the function of both targets, should be considered. In the present study, we assessed the effects of atorvastatin (Lipitor), celecoxib (Celebrex) and tipifarnib (Zarnestra) on the growth of human pancreatic cancer. In the in vitro studies, we found that treatment of human pancreatic tumor cells with a combination of atorvastatin, celecoxib and tipifarnib had a stronger inhibitory effect on growth and a stronger stimulatory effect on apoptosis than each drug alone or for any combination of two drugs. We also found that treatment of Panc-1 cells with a combination of all three drugs strongly decreased the levels of phosphorylated Erk1/2 and Akt. In an animal model of xenograft tumors in severe combined immunodeficient (SCID) mice, we found that daily i.p. injections of a combination of atorvastatin, celecoxib and tipifarnib had a stronger inhibitory effect on the growth of the tumors in mice than each drug alone or for any combination of two drugs. The results of our study indicate that a combination of atorvastatin, celecoxib and tipifarnib may be an effective strategy for the treatment of pancreatic cancer.
Related JoVE Video
Prognosis and weaning of elderly multiple organ dysfunction syndrome patients with invasive mechanical ventilation.
Chin. Med. J.
PUBLISHED: 01-04-2014
Show Abstract
Hide Abstract
Elderly multiple organ dysfunction syndrome (MODS) patients receiving invasive mechanical ventilation have poor prognosis in intensive care units (ICUs). We studied the usefulness of four commonly used severity scores and extrapulmonary factors that affected weaning to predict outcome of such patients.
Related JoVE Video
Related JoVE Video
Characterization of Lung Function Impairment in Adults with Bronchiectasis.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Characteristics of lung function impairment in bronchiectasis is not fully understood.
Related JoVE Video
MiR-21 Simultaneously Regulates ERK1 Signaling in HSC Activation and Hepatocyte EMT in Hepatic Fibrosis.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
MicroRNA-21 (miR-21) plays an important role in the pathogenesis and progression of liver fibrosis. Here, we determined the serum and hepatic content of miR-21 in patients with liver cirrhosis and rats with dimethylnitrosamine-induced hepatic cirrhosis and examined the effects of miR-21 on SPRY2 and HNF4? in modulating ERK1 signaling in hepatic stellate cells (HSCs) and epithelial-mesenchymal transition (EMT) of hepatocytes.
Related JoVE Video
Risk factors for acute stroke among South Asians compared to other racial/ethnic groups.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Studies of racial/ethnic variations in stroke rarely consider the South Asian population, one of the fastest growing sub-groups in the United States. This study compared risk factors for stroke among South Asians with those for whites, African-Americans, and Hispanics.
Related JoVE Video
Delivery of bioactive lipids from composite microgel-microsphere injectable scaffolds enhances stem cell recruitment and skeletal repair.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
In this study, a microgel composed of chitosan and inorganic phosphates was used to deliver poly(lactic-co-glycolic acid) (PLAGA) microspheres loaded with sphingolipid growth factor FTY720 to critical size cranial defects in Sprague Dawley rats. We show that sustained release of FTY720 from injected microspheres used alone or in combination with recombinant human bone morphogenic protein-2 (rhBMP2) improves defect vascularization and bone formation in the presence and absence of rhBMP2 as evaluated by quantitative microCT and histological measurements. Moreover, sustained delivery of FTY720 from PLAGA and local targeting of sphingosine 1-phosphate (S1P) receptors reduces CD45+ inflammatory cell infiltration, promotes endogenous recruitment of CD29+CD90+ bone progenitor cells and enhances the efficacy of rhBMP2 from chitosan microgels. Companion in vitro studies suggest that selective activation of sphingosine receptor subtype-3 (S1P3) via FTY720 treatment induces smad-1 phosphorylation in bone-marrow stromal cells. Additionally, FTY720 enhances stromal cell-derived factor-1 (SDF-1) mediated chemotaxis of CD90+CD11B-CD45- bone progenitor cells in vitro after stimulation with rhBMP2. We believe that use of such small molecule delivery formulations to recruit endogenous bone progenitors may be an attractive alternative to exogenous cell-based therapy.
Related JoVE Video
Lipid profiles and ischemic stroke risk: variations by sex within racial/ethnic groups.
Int J Womens Health
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Evidence implicates lipid abnormalities as important but modifiable risk factors for stroke. This study assesses whether hypercholesterolemia can be used to predict the risk for etiologic subtypes of ischemic stroke between sexes within racial/ethnic groups. Data elements related to stroke risk, diagnosis, and outcomes were abstracted from the medical records of 3,290 acute stroke admissions between 2006 and 2010 at a regional stroke center. Sex comparison within racial/ethnic groups revealed that South Asian and Hispanic men had a higher proportion of ischemic stroke than women, while the inverse was true for Whites and African Americans (P=0.0014). All women, except South Asian women, had higher mean plasma total cholesterol and higher blood circulating low-density lipoprotein levels (?100 mg/dL) than men at the time of their admissions. The incidence of large-artery atherosclerosis (LAA) was more common among women than men, except among Hispanics, where men tended to have higher incidences. A regression analysis that considered patients diagnosed with either LAA or small-artery occlusion etiologic subtype as the outcomes and high-density lipoproteins and triglycerides as predictors showed inconsistent associations between lipid profiles and the incidence of these subtypes between the sexes within racial/ethnic groups. In conclusion, our investigation suggests that women stroke patients may be at increased risk for stroke etiologic subtype LAA than men. Although the higher prevalence of stroke risk factors examined in this study predicts the increase in the incidence of the disease, lack of knowledge/awareness and lack of affordable treatments for stroke risk factors among women and immigrants/non-US-born subpopulations may explain the observed associations.
Related JoVE Video
Genome-wide association study identified copy number variants important for appendicular lean mass.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Skeletal muscle is a major component of the human body. Age-related loss of muscle mass and function contributes to some public health problems such as sarcopenia and osteoporosis. Skeletal muscle, mainly composed of appendicular lean mass (ALM), is a heritable trait. Copy number variation (CNV) is a common type of human genome variant which may play an important role in the etiology of many human diseases. In this study, we performed genome-wide association analyses of CNV for ALM in 2,286 Caucasian subjects. We then replicated the major findings in 1,627 Chinese subjects. Two CNVs, CNV1191 and CNV2580, were detected to be associated with ALM (p?=?2.26×10(-2) and 3.34×10(-3), respectively). In the Chinese replication sample, the two CNVs achieved p-values of 3.26×10(-2) and 0.107, respectively. CNV1191 covers a gene, GTPase of the immunity-associated protein family (GIMAP1), which is important for skeletal muscle cell survival/death in humans. CNV2580 is located in the Serine hydrolase-like protein (SERHL) gene, which plays an important role in normal peroxisome function and skeletal muscle growth in response to mechanical stimuli. In summary, our study suggested two novel CNVs and the related genes that may contribute to variation in ALM.
Related JoVE Video
Macrolide therapy in adults and children with non-cystic fibrosis bronchiectasis: a systematic review and meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
A systematic review and meta-analysis was conducted to evaluate the efficacy and safety of macrolide therapy in adults and children with bronchiectasis.
Related JoVE Video
Autism associated gene, engrailed2, and flanking gene levels are altered in post-mortem cerebellum.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Previous genetic studies demonstrated association between the transcription factor engrailed2 (EN2) and Autism Spectrum Disorder (ASD). Subsequent molecular analysis determined that the EN2 ASD-associated haplotype (rs1861972-rs1861973 A-C) functions as a transcriptional activator to increase gene expression. EN2 is flanked by 5 genes, serotonin receptor5a (HTR5A), insulin induced gene1 (INSIG1), canopy1 homolog (CNPY1), RNA binding motif protein33 (RBM33), and sonic hedgehog (SHH). These flanking genes are co-expressed with EN2 during development and coordinate similar developmental processes. To investigate if mRNA levels for these genes are altered in individuals with autism, post-mortem analysis was performed.
Related JoVE Video
Immunosuppressive drugs modulate the replication of hepatitis B virus (HBV) in a hydrodynamic injection mouse model.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Hepatitis B virus (HBV) reactivation and recurrence are common in patients under immunosuppression and can be controlled by hepatitis B immunoglobulin, antivirals, and hepatitis B vaccine. However, the detailed analysis of HBV infection under immunosuppression is essential for the prophylaxis and therapy for HBV reactivation and recurrence. In this study, HBV replication and T cell responses were analyzed in a HBV-transfected mouse model under immunosuppressive therapy. During the treatment, HBV replication was at a high level in mice treated with dexamethasone, cyclosporine, and cyclophosphamide, whereas was terminated in mice treated with mycophenolate mofetil. After the withdrawal, HBV replication was at low or high levels in the dexamethasone-treated mice or in both cyclosporine- and cyclophosphamide-treated mice. The early withdrawal of cyclosporine allowed the recovery of suppressed T cell responses and led to subsequent HBV clearance, while the adoptive immune transfer to the mice with HBV persistence led to HBV suppression. Taken together, long-term HBV persistence under immunosuppression depends on the immunosuppressive drugs used and on the treatment duration and is mediated by the suppressed intrahepatic CD8 T cell response. These data may be helpful for individualized immunosuppressive therapy in patients with high risk of HBV reactivation and recurrence, and the mouse system is suitable for studying HBV reactivation and recurrence under immunosuppression.
Related JoVE Video
Blockage of the Upregulation of Voltage-Gated Sodium Channel Nav1.3 Improves Outcomes after Experimental Traumatic Brain Injury.
J. Neurotrauma
PUBLISHED: 12-06-2013
Show Abstract
Hide Abstract
Abstract Excessive active voltage-gated sodium channels are responsible for the cellular abnormalities associated with secondary brain injury following traumatic brain injury (TBI). We previously presented evidence that significant upregulation of Nav1.3 expression occurs in the rat cortex at 2?h and 12?h post-TBI and is correlated with TBI severity. In our current study, we tested the hypothesis that blocking upregulation of Nav1.3 expression in vivo in the acute stage post-TBI attenuates the secondary brain injury associated with TBI. We administered either antisense oligodeoxynucleotides (ODN) targeting Nav1.3 or artificial cerebrospinal fluid (aCSF) at 2?h, 4?h, 6?h, and 8?h following TBI. Control sham animals received aCSF administration at the same time points. At 12?h post-TBI, Nav1.3 messenger ribonucleic acid (mRNA) levels in bilateral hippocampi of the aCSF group were significantly elevated, compared with the sham and ODN groups (p<0.01). However, the Nav1.3 mRNA levels in the uninjured contralateral hippocampus of the ODN group were significantly lowered, compared with the sham group (p<0.01). Treatment with antisense ODN significantly decreased the number of degenerating neurons in the ipsilateral hippocampal CA3 and hilar region (p<0.01). A set of left-to-right ratio value analyzed by magnetic resonance imaging T2 image on one day, three days, and seven days post-TBI showed marked edema in the ipsilateral hemisphere of the aCSF group, compared with that of the ODN group (p<0.05). The Morris water maze memory retention test showed that both the aCSF and ODN groups took longer to find a hidden platform, compared with the sham group (p<0.01). However, latency in the aCSF group was significantly higher than in the ODN group (p<0.05). Our in vivo Nav1.3 inhibition studies suggest that therapeutic strategies to block upregulation of Nav1.3 expression in the brain may improve outcomes following TBI.
Related JoVE Video
MUC1 in macrophage contributions to cigarette smoke-induced lung cancer.
Cancer Res.
PUBLISHED: 11-26-2013
Show Abstract
Hide Abstract
Expression of the pro-oncogenic mucin MUC1 is elevated by inflammation in airway epithelial cells, but the contributions of MUC1 to the development of lung cancer are uncertain. In this study, we developed our finding that cigarette smoke (CS) increases Muc1 expression in lung macrophages, where we hypothesized it might contribute to CS-induced transformation of bronchial epithelial cells. In human macrophages, CS extract (CSE) strongly induced MUC1 expression through a mechanism involving the nuclear receptor PPAR-?. CSE-induced ERK activation was also required for MUC1 expression, but it had little effect on MUC1 transcription. RNAi-mediated attenuation of MUC1 suppressed CSE-induced secretion of TNF-? from macrophages, by suppressing the activity of the TNF-? processing enzyme TACE, arguing that MUC1 is required for CSE-induced and TACE-mediated TNF-? secretion. Similarly, MUC1 blockade after CSE inducion through suppression of PPAR-? or ERK inhibited TACE activity and TNF-? secretion. Conditioned media from CSE-treated macrophages induced MUC1 expression and potentiated CSE-induced transformation of human bronchial epithelial cells (HBEC) in a TNF-?-dependent manner. Together, our results identify a signaling pathway involving PPAR-?, ERK and MUC1 that is used by CSE to trigger TNF-? secretion from macrophages. Further, our results show how that MUC1 contributes to smoking-induced lung cancers that are driven by inflammatory signals driven by macrophages.
Related JoVE Video
Multistage genome-wide association meta-analyses identified two new loci for bone mineral density.
Hum. Mol. Genet.
PUBLISHED: 11-17-2013
Show Abstract
Hide Abstract
Aiming to identify novel genetic variants and to confirm previously identified genetic variants associated with bone mineral density (BMD), we conducted a three-stage genome-wide association (GWA) meta-analysis in 27 061 study subjects. Stage 1 meta-analyzed seven GWA samples and 11 140 subjects for BMDs at the lumbar spine, hip and femoral neck, followed by a Stage 2 in silico replication of 33 SNPs in 9258 subjects, and by a Stage 3 de novo validation of three SNPs in 6663 subjects. Combining evidence from all the stages, we have identified two novel loci that have not been reported previously at the genome-wide significance (GWS; 5.0 × 10(-8)) level: 14q24.2 (rs227425, P-value 3.98 × 10(-13), SMOC1) in the combined sample of males and females and 21q22.13 (rs170183, P-value 4.15 × 10(-9), CLDN14) in the female-specific sample. The two newly identified SNPs were also significant in the GEnetic Factors for OSteoporosis consortium (GEFOS, n = 32 960) summary results. We have also independently confirmed 13 previously reported loci at the GWS level: 1p36.12 (ZBTB40), 1p31.3 (GPR177), 4p16.3 (FGFRL1), 4q22.1 (MEPE), 5q14.3 (MEF2C), 6q25.1 (C6orf97, ESR1), 7q21.3 (FLJ42280, SHFM1), 7q31.31 (FAM3C, WNT16), 8q24.12 (TNFRSF11B), 11p15.3 (SOX6), 11q13.4 (LRP5), 13q14.11 (AKAP11) and 16q24 (FOXL1). Gene expression analysis in osteogenic cells implied potential functional association of the two candidate genes (SMOC1 and CLDN14) in bone metabolism. Our findings independently confirm previously identified biological pathways underlying bone metabolism and contribute to the discovery of novel pathways, thus providing valuable insights into the intervention and treatment of osteoporosis.
Related JoVE Video
Genetic factors, viral infection, other factors and liver cancer: an update on current progress.
Asian Pac. J. Cancer Prev.
PUBLISHED: 11-02-2013
Show Abstract
Hide Abstract
Primary liver cancer is one of the most common cancers at the global level, accounting for half of all cancers in some undeveloped countries. This disease tends to occur in livers damaged through alcohol abuse, or chronic infection with hepatitis B and C, on a background of cirrhosis. Various cancer-causing substances are associated with primary liver cancer, including certain pesticides and such chemicals as vinyl chloride and arsenic. The strong association between HBV infection and liver cancer is well documented in epidemiological studies. It is generally acknowledged that the virus is involved through long term chronic infection, frequently associated with cirrhosis, suggesting a nonspecific mechanism triggered by the immune response. Chronic inflammation of liver, continuous cell death, abnormal cell growth, would increase the occurrence rate of genetic alterations and risk of disease. However, the statistics indicated that only about one fifth of HBV carries would develop HCC in lifetime, suggesting that individual variation in genome would also influence the susceptibility of HCC. The goal of this review is to highlight present level of knowledge on the role of viral infection and genetic variation in the development of liver cancer.
Related JoVE Video
Impact of Size in Pancreatic Islet Transplantation and Potential Interventions to Improve Outcome.
Cell Transplant
PUBLISHED: 10-23-2013
Show Abstract
Hide Abstract
Better results have been recently reported inclinical pancreatic islet transplantation (ITX) due mostly to improved isolation techniques and immunosuppression; however, some limitations still exist. It is known that following transplantation from 30 to 60% of the islets is lost. In our study, we have investigated: 1) the role of size as a factor affecting islet engraftment and, 2) potential procedural manipulations to increase the number of smaller functional islets that can be transplanted. C57/BL10 mice were used as donors and recipients in a syngeneic islet transplant model. Isolated islets were divided by size (large, >300 ?m; medium 150-300 ?m; small, <150 ?m). Each size was transplanted in chemically induced diabetic mice as full (600 IEq), suboptimal (400 IEq), and marginal mass (200 IEq). Control animals received all size islets. Engraftment was defined as reversal of diabetes by day 7 posttransplantation. When the superiority of smaller islets was observed, strategies of overdigestion and fragmentation wereadopted during islet isolation in the attempt to reduce islet size and improve engraftment. Smaller islets were significantly superior in engraftment as compared to medium, large, and control (all sizes) groups. This was more evident when marginal mass data were compared. In all masses, success decreased as islet sizes increased. Once islets were engrafted, functionality was notaffected by size. When larger islets were fragmented, a significant decrease in islet functionality was observed. On the contrary, if pancreata were slightly over-digested, although not as successfulas small naive islets, an increase in engraftment was observed when compared to the control group. In conclusion, smaller islets are superior in engraftment following islet transplantation. Fragmentation has a deleterious effect on islet engraftment. Islet isolations can be performed reducing islet size with slight over-digestion and it can be safely adopted to improve clinical outcome.
Related JoVE Video
Oral caffeine during voluntary exercise markedly inhibits skin carcinogenesis and decreases inflammatory cytokines in UVB-treated mice.
Nutr Cancer
PUBLISHED: 09-26-2013
Show Abstract
Hide Abstract
Ultraviolet B (UVB)-pretreated SKH-1 mice were treated with water, caffeine (0.1 mg/ml), voluntary running wheel exercise (RW) or caffeine together with RW for 14 wk. Treatment of the mice with caffeine, RW, or caffeine plus RW decreased skin tumors per mouse by 27%, 35%, and 62%, respectively, and the tumor volume per mouse was decreased by 61%, 70%, and 85%, respectively. In mechanistic studies, mice were treated with water, caffeine, RW, or caffeine plus RW for 2 wk prior to a single irradiation with UVB. Caffeine plus RW increased RW activity by 22% when compared with RW alone. Caffeine ingestion was not significantly different between groups. Treatment of mice with caffeine plus RW for 2 wk decreased the weight of the parametrial fat pads and stimulated the formation of UVB-induced apoptosis to a greater extent than treatment with caffeine or RW alone. An antibody array revealed that caffeine plus RW administered to mice fed a high-fat diet and irradiated with UVB decreased the epidermal levels of lipopolysaccharide-induced CXC chemokine, soluble TNF alpha receptor-1, and macrophage inflammatory protein-1?. Overall, caffeine during RW exerts a stronger effect than either treatment alone for decreasing tissue fat, increasing UVB-induced apoptosis, lowering the levels of cytokines associated with inflammation and for inhibiting UVB-induced carcinogenesis.
Related JoVE Video
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
Show Abstract
Hide Abstract
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.
Related JoVE Video
Meta-analysis of genome-wide association data identifies novel susceptibility loci for obesity.
Hum. Mol. Genet.
PUBLISHED: 09-23-2013
Show Abstract
Hide Abstract
Obesity is a major public health problem with strong genetic determination. Multiple genetic variants have been implicated for obesity by conducting genome-wide association (GWA) studies, primarily focused on body mass index (BMI). Fat body mass (FBM) is phenotypically more homogeneous than BMI and is more appropriate for obesity research; however, relatively few studies have been conducted on FBM. Aiming to identify variants associated with obesity, we carried out meta-analyses of seven GWA studies for BMI-related traits including FBM, and followed these analyses by de novo replication. The discovery cohorts consisted of 21 969 individuals from diverse ethnic populations and a total of over 4 million genotyped or imputed SNPs. The de novo replication cohorts consisted of 6663 subjects from two independent samples. To complement individual SNP-based association analyses, we also carried out gene-based GWA analyses in which all variations within a gene were considered jointly. Individual SNP-based association analyses identified a novel locus 1q21 [rs2230061, CTSS (Cathepsin S)] that was associated with FBM after the adjustment of lean body mass (LBM) (P = 3.57 × 10(-8)) at the genome-wide significance level. Gene-based association analyses identified a novel gene NLK (nemo-like kinase) in 17q11 that was significantly associated with FBM adjusted by LBM. In addition, we confirmed three previously reported obesity susceptibility loci: 16q12 [rs62033400, P = 1.97 × 10(-14), FTO (fat mass and obesity associated)], 18q22 [rs6567160, P = 8.09 × 10(-19), MC4R (melanocortin 4 receptor)] and 2p25 [rs939583, P = 1.07 × 10(-7), TMEM18 (transmembrane protein 18)]. We also found that rs6567160 may exert pleiotropic effects to both FBM and LBM. Our results provide additional insights into the molecular genetic basis of obesity and may provide future targets for effective prevention and therapeutic intervention.
Related JoVE Video
[The value of coexisting pneumonia and British Thoracic Society CURB-65 score in predicting early mortality rate in patients with acute exacerbation of chronic obstructive pulmonary disease].
Zhonghua Jie He He Hu Xi Za Zhi
PUBLISHED: 08-16-2013
Show Abstract
Hide Abstract
To investigate the value of coexisting pneumonia and British Thoracic Society CURB-65 score in predicting early mortality in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).
Related JoVE Video
Oral administration of a gemini vitamin D analog, a synthetic triterpenoid and the combination prevents mammary tumorigenesis driven by ErbB2 overexpression.
Cancer Prev Res (Phila)
PUBLISHED: 07-15-2013
Show Abstract
Hide Abstract
HER2 (or ErbB2), a member of ErbB receptor tyrosine kinases, is overexpressed in approximately 20% of human breast cancer, and the ErbB2 signaling pathway is a critical therapeutic target for ErbB2-overexpressing breast cancer. We investigated the inhibitory effects of the Gemini vitamin D analog BXL0124, the synthetic triterpenoid CDDO-Im and the combination on the tumorigenesis of ErbB2-overexpressing breast cancer. MMTV-ErbB2/neu transgenic mice were treated with BXL0124, CDDO-Im, or the combination from three months of age until the end of the experiment. Formation and growth of MMTV-ErbB2/neu mammary tumors were monitored every week, and all three treatments delayed the development of mammary tumors without significant toxicity. Decreased activation of ErbB2 as well as other ErbB receptors, ErbB1 and ErbB3, in MMTV-ErbB2/neu mammary tumors was shown by all treatments. Protein levels of downstream targets of the ErbB2 signaling pathway, including activated-Erk1/2, activated-Akt, c-Myc, CycD1, and Bcl2, were repressed by all three treatments, with the combination treatment exhibiting the strongest effects. To investigate therapeutic efficacy, the combination of BXL0124 and CDDO-Im was given to MMTV-ErbB2/neu mice after mammary tumors were established between 23 and 30 weeks of age. Short-term treatment with the combination did not show effects on tumor growth nor the ErbB2 signaling pathway. The present study shows BXL0124, CDDO-Im, and the combination as potential agents for prevention, but not treatment, against the tumorigenesis of ErbB2-overexpressing breast cancer.
Related JoVE Video
Variability and trend of multiple blood lead measures among construction and manufacturing workers.
Occup Environ Med
PUBLISHED: 07-09-2013
Show Abstract
Hide Abstract
This study evaluated multiple blood lead measures collected over time and assessed differences arising from exposure and testing variability.
Related JoVE Video
Establishment and application of hepatitis B virus persistent replication model in IFNAR(-/-) mouse.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 06-17-2013
Show Abstract
Hide Abstract
The type I interferon and IFNAR play an important role in hepatitis B virus (HBV) infection and anti-HBV therapy. However, its mechanism of action is still poorly understood. To gain more insights into the role of type I interferon and type I interferon receptor (IFNAR) in HBV infection, we established an HBV persistent replication IFNAR knockout (IFNAR(-/-)) mouse model and preliminarily applied this model. At first, the progeny of IFNAR(-/-) mouse was reproduced. Then hydrodynamic injection with pAAV/HBV1.2 plasmid was conducted to establish the persistent HBV replication IFNAR(-/-) mouse model. At last, we applied this model to evaluate the effect of nucleoside analogues entecavir (ETV) on HBV replication. It was found that there was no difference in the serum HBsAg and HBeAg levels and HBcAg expression in the liver tissue between the ETV treated groups and normal saline (NS) treated group, but the serum HBV DNA levels were significantly suppressed 10, 25, 40 and 55 days after the ETV treatment [P=0.035, P=0.00, P=0.149 and P=0.084, IFNAR knockout (KO) control group vs. C57BL/6 ETV groups, respectively; P=0.081, P=0.001, P=0.243 and P=0.147, IFNAR KO control group vs. IFNAR KO ETV groups, respectively]. Interestingly, there was no difference in serum HBV DNA levels between the ETV treated IFNAR(-/-) and C57BL/6 mice. This result suggests that HBV suppression during ETV treatments doesnt depend on type I interferon and IFNAR. Collectively, persistent HBV replication IFNAR(-/-) mouse model that we established is a useful and convenient tool to detect the function of the type I interferon and IFNAR in HBV infection and anti-HBV treatments.
Related JoVE Video
Autocrine TNF-?-mediated NF-?B activation is a determinant for evasion of CD40-induced cytotoxicity in cancer cells.
Biochem. Biophys. Res. Commun.
PUBLISHED: 05-28-2013
Show Abstract
Hide Abstract
Activation of CD40 by CD40L results in diverse effects on different malignant cells, causing either promotion of survival, growth and resistance to chemotherapy, or induction of cytostasis and apoptosis. The molecular mechanisms underlying CD40-mediated growth regulation and apoptosis induction in cancer cell are not fully understood. In this study, we investigated the role of NF-?B activation in CD40-mediated cytotoxicity in cancer cells. The results show that activation of CD40 by recombinant soluble CD40 ligand (rsCD40L) readily induced NF-?B activation and blocking NF-?B significantly enhanced rsCD40L-induced apoptosis in cancer cells. Importantly, autocrine of TNF-? induced by rsCD40L was indispensable for both NF-?B activation and cytotoxicity induction, establishing a dual role of autocrine TNF-? that constitutes both pro-apoptotic and anti-apoptotic arms of CD40 signaling. Our results indicate that autocrine TNF-?-mediated NF-?B activation is a determinant for cancer cells evasion of CD40L-induced cytotoxicity and blocking NF-?B may have potential for improve the value of CD40 as an anticancer agent.
Related JoVE Video
Does ambient air pollution trigger stillbirth?
Epidemiology
PUBLISHED: 05-17-2013
Show Abstract
Hide Abstract
We previously reported an increased risk of stillbirth associated with increases in trimester-specific ambient air pollutant concentrations. Here, we consider whether sudden increase in the mean ambient air pollutant concentration immediately before delivery triggers stillbirth.
Related JoVE Video
Mutagenicity and tumorigenicity of the four enantiopure bay-region 3,4-diol-1,2-epoxide isomers of dibenz[a,h]anthracene.
Carcinogenesis
PUBLISHED: 05-13-2013
Show Abstract
Hide Abstract
Each enantiomer of the diastereomeric pair of bay-region dibenz[a,h]anthracene 3,4-diol-1,2-epoxides in which the benzylic 4-hydroxyl group and epoxide oxygen are either cis (isomer 1) or trans (isomer 2) were evaluated for mutagenic activity. In strains TA 98 and TA 100 of Salmonella typhimurium, the diol epoxide with (1S,2R,3S,4R) absolute configuration [(-)-diol epoxide-1] had the highest mutagenic activity. In Chinese hamster V-79 cells, the diol epoxide with (1R,2S,3S,4R) absolute configuration [(+)-diol epoxide-2] had the highest mutagenic activity. The (1R,2S,3R,4S) diol epoxide [(+)-diol epoxide-1] also had appreciable activity, whereas the other two bay-region diol epoxide enantiomers had very low activity. In tumor studies, the (1R,2S,3S,4R) enantiomer was the only diol epoxide isomer tested that had strong activity as a tumor initiator on mouse skin and in causing lung and liver tumors when injected into newborn mice. This stereoisomer was about one-third as active as the parent hydrocarbon, dibenz[a,h]anthracene as a tumor initiator on mouse skin; it was several-fold more active than dibenz[a,h]anthracene as a lung and liver carcinogen when injected into newborn mice. (-)-(3R,4R)-3?,4?-dihydroxy-3,4-dihydro-dibenz[a,h]anthracene [(-)-3,4-dihydrodiol] was slightly more active than dibenz[a,h]anthracene as a tumor initiator on mouse skin, whereas (+)-(3S,4S)-3?,4?-dihydroxy-3,4-dihydro-dibenz[a,h]anthracene [(+)-3,4-dihydrodiol] had only very weak activity. The present investigation and previous studies with the corresponding four possible enantiopure bay-region diol epoxide enantiomers/diastereomers of benzo[a]pyrene, benz[a]anthracene, chrysene, benzo[c]phenanthrene, dibenz[c,h]acridine, dibenz[a,h]acridine and dibenz[a,h]anthracene indicate that the bay-region diol epoxide enantiomer with [R,S,S,R] absolute stereochemistry has high tumorigenic activity on mouse skin and in newborn mice.
Related JoVE Video
Cancer-specific Survival After Metastasis Following Primary Radical Prostatectomy Compared with Radiation Therapy in Prostate Cancer Patients: Results of a Population-based, Propensity Score-Matched Analysis.
Eur. Urol.
PUBLISHED: 05-08-2013
Show Abstract
Hide Abstract
Data regarding the difference in the clinical course from metastasis to prostate cancer-specific mortality (PCSM) following radical prostatectomy (RP) compared with radiation therapy (RT) are lacking.
Related JoVE Video
RIP1 potentiates BPDE-induced transformation in human bronchial epithelial cells through catalase-mediated suppression of excessive reactive oxygen species.
Carcinogenesis
PUBLISHED: 04-30-2013
Show Abstract
Hide Abstract
Cell survival signaling is important for the malignant phenotypes of cancer cells. Although the role of receptor-interacting protein 1 (RIP1) in cell survival signaling is well documented, whether RIP1 is directly involved in cancer development has never been studied. In this report, we found that RIP1 expression is substantially increased in human non-small cell lung cancer and mouse lung tumor tissues. RIP1 expression was remarkably increased in cigarette smoke-exposed mouse lung. In human bronchial epithelial cells (HBECs), RIP1 was significantly induced by cigarette smoke extract or benzo[a]pyrene diol epoxide (BPDE), the active form of the tobacco-specific carcinogen benzo(a)pyrene. In RIP1 knockdown HBECs, BPDE-induced cytotoxicity was significantly increased, which was associated with induction of cellular reactive oxygen species (ROS) and activation of mitogen-activated protein kinases (MAPKs), including c-jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38. Scavenging ROS suppressed BPDE-induced MAPK activation and inhibiting ROS or MAPKs substantially blocked BPDE-induced cytotoxicity, suggesting ROS-mediated MAPK activation is involved in BPDE-induced cell death. The ROS-reducing enzyme catalase is destabilized in an ERK- and JNK-dependent manner in RIP1 knockdown HBECs and application of catalase effectively blocked BPDE-induced ROS accumulation and cytotoxicity. Importantly, BPDE-induced transformation of HBECs was significantly reduced when RIP1 expression was suppressed. Altogether, these results strongly suggest an oncogenic role for RIP1, which promotes malignant transformation through protecting DNA-damaged cells against carcinogen-induced cytotoxicity associated with excessive ROS production.
Related JoVE Video
Probing the RNA Binding Surface of the HIV-1 Nucleocapsid Protein by Site-Directed Mutagenesis.
Biochemistry
PUBLISHED: 04-30-2013
Show Abstract
Hide Abstract
The highly conserved nucleocapsid protein domain in HIV-1 recognizes and binds SL3 in genomic RNA. In this work, we used the structure of the NCp7-SL3 RNA complex to guide the construction of 16 NCp7 mutants to probe the RNA binding surface of the protein [De Guzman, R. N., et al. (1998) Science 279, 384-388]. Thirteen residues with functional or structural significance were mutated individually to Ala (Asn(5), Phe(6), Val(13), Phe(16), Asn(17), Gly(19), Glu(21), Ile(24), Gln(45), Met(46), Gly(22), Pro(31), and Gly(40)), and three salt bridge switch mutants exchanged Lys and Glu (Lys(14)-Glu(21), Lys(33)-Glu(42), and Lys(38)-Glu(51)). Dissociation constants (Kd) determined by fluorescence titration and isothermal titration calorimetry were used to compare affinities of SL3 for the variant proteins to that for the wild type. The F16A (Phe(16) to Ala) variant showed a 25-fold reduction in affinity, consistent with a loss of organized structure in f1, the proteins first zinc finger. I24A, Q45A, and M46A reduced affinity by 2-5-fold; these residues occupy nearly equivalent positions in f1 and f2. E21A increased affinity by 3-fold, perhaps because of the mutants increased net positive charge. Among the salt bridge switch mutants, only K14E/E21K in f1 caused a substantial change in affinity (5-fold reduction), binding SL3 with a biphasic binding isotherm. Aside from these six variants, most of the mutations studied have relatively minor effects on the stability of the complex. We conclude that many side chain interactions in the wild-type complex contribute little to stability or can be compensated by new contacts in the mutants.
Related JoVE Video
Evaluation of the combinative application of SDS and sodium deoxycholate to the LC-MS-based shotgun analysis of membrane proteomes.
J Sep Sci
PUBLISHED: 04-20-2013
Show Abstract
Hide Abstract
SDS and sodium deoxycholate (SDC) as two representative detergents have been widely used in LC-MS/MS-based shotgun analysis of membrane proteomes. However, some inherent disadvantages limit their applications such as interference with MS analysis or their weak ability to disrupt membranes. To address this, the combinative application of SDS and SDC was developed and evaluated in our study, which comprehensively used the strong ability of SDS to lyse membranes and solubilize hydrophobic membrane proteins, and the high efficiencies of an optimized acetone precipitation method and SDC in sample clean-up, protein recovery, and redissolution and digestion of precipitated proteins. The comparative study using a rat-liver-membrane-enriched sample showed that, compared with other three commonly used methods including the filter-aided sample preparation strategy, the combinative method not only increased the identified number of total proteins, membrane proteins, and integral membrane proteins by an average of 19.8, 23.9, and 24.8%, respectively, but also led to the identification of the highest number of matching peptides. All these results demonstrate that the method yielded better recovery and reliability in the identification of the proteins especially highly hydrophobic integral membrane proteins than the other three methods, and thereby has more potential in shotgun membrane proteomics.
Related JoVE Video
Racial disparities in red meat and poultry intake and breast cancer risk.
Cancer Causes Control
PUBLISHED: 04-12-2013
Show Abstract
Hide Abstract
Research on the role of red meat and poultry consumption in breast carcinogenesis is inconclusive, but the evidence in African-American (AA) women is lacking. The association between consuming meat and breast cancer risk was examined in the Womens Circle of Health Study involving 803 AA cases, 889 AA controls, 755 Caucasian cases, and 701 Caucasian controls.
Related JoVE Video
Aldehyde dehydrogenase 3A1 protects airway epithelial cells from cigarette smoke-induced DNA damage and cytotoxicity.
Free Radic. Biol. Med.
PUBLISHED: 03-29-2013
Show Abstract
Hide Abstract
Aldehyde dehydrogenase 3A1 (ALDH3A1), an ALDH superfamily member, catalyzes the oxidation of reactive aldehydes, highly toxic components of cigarette smoke (CS). Even so, the role of ALDH3A1 in CS-induced cytotoxicity and DNA damage has not been examined. Among all of the ALDH superfamily members, ALDH3A1 mRNA levels showed the greatest induction in response to CS extract (CSE) exposure of primary human bronchial epithelial cells (HBECs). ALDH3A1 protein accumulation was accompanied by increased ALDH enzymatic activity in CSE-exposed immortalized HBECs. The effects of overexpression or suppression of ALDH3A1 on CSE-induced cytotoxicity and DNA damage (?H2AX) were evaluated in cultured immortalized HBECs. Enforced expression of ALDH3A1 attenuated cytotoxicity and downregulated ?H2AX. SiRNA-mediated suppression of ALDH3A1 blocked ALDH enzymatic activity and augmented cytotoxicity in CSE-exposed cells. Our results suggest that the availability of ALDH3A1 is important for cell survival against CSE in HBECs.
Related JoVE Video
Methods of designing two-stage winner trials with survival outcomes.
Stat Med
PUBLISHED: 03-18-2013
Show Abstract
Hide Abstract
In drug development, especially for oncology studies, a recent proposal is to combine a costly phase II dose selection study with a subsequent phase III study into a single trial that compares the selected (winning) dose from the first stage with the control group. This design may also be used in phase III trials, in which the winning active treatment regimen, selected at the first stage, is compared with the control group at the second stage. This design is known as a two-stage winner design, as proposed by Shun et al. (2008) for continuous outcomes. Time-to-event data are often analyzed in oncology trials. In order to derive the critical value and power of this design, per Shun et al. (2008), it is essential to calculate the asymptotic covariance and correlation of the log-rank statistics for survival outcomes between the two stages. In this paper, we derive the asymptotic covariance and correlation, and provide additional approximate design parameters. Examples are given to illustrate the method, and simulations are performed to evaluate the veracity of these approximate design parameters. Copyright © 2013 John Wiley & Sons, Ltd.
Related JoVE Video
Proteasomal cleavage site prediction of protein antigen using BP neural network based on a new set of amino acid descriptor.
J Mol Model
PUBLISHED: 03-18-2013
Show Abstract
Hide Abstract
The accurate identification of cytotoxic T lymphocyte epitopes is becoming increasingly important in peptide vaccine design. The ubiquitin-proteasome system plays a key role in processing and presenting major histocompatibility complex class I restricted epitopes by degrading the antigenic protein. To enhance the specificity and efficiency of epitope prediction and identification, the recognition mode between the ubiquitin-proteasome complex and the protein antigen must be considered. Hence, a model that accurately predicts proteasomal cleavage must be established. This study proposes a new set of parameters to characterize the cleavage window and uses a backpropagation neural network algorithm to build a model that accurately predicts proteasomal cleavage. The accuracy of the prediction model, which depends on the window sizes of the cleavage, reaches 95.454% for the N-terminus and 95.011% for the C-terminus. The results show that the identification of proteasomal cleavage sites depends on the sequence next to it and that the prediction performance of the C-terminus is better than that of the N-terminus on average. Thus, models based on the properties of amino acids can be highly reliable and reflect the structural features of interactions between proteasomes and peptide sequences.
Related JoVE Video
Proteomic analysis of the inhibitory effect of epigallocatechin gallate on lipid accumulation in human HepG2 cells.
Proteome Sci
PUBLISHED: 02-25-2013
Show Abstract
Hide Abstract
(-)-Epigallocatechin-3-gallate (EGCG), the most abundant catechin found in green tea, effectively reduces body weight and tissue and blood lipid accumulation. To explore the mechanism by which EGCG inhibits cellular lipid accumulation in free fatty acid (FFA) induced HepG2 cell culture, we investigated the proteome change of FFA-induced HepG2 cells exposed to EGCG using two-dimensional gel electrophoresis and mass spectrometry.
Related JoVE Video
Sodium laurate, a novel protease- and mass spectrometry-compatible detergent for mass spectrometry-based membrane proteomics.
PLoS ONE
PUBLISHED: 02-18-2013
Show Abstract
Hide Abstract
The hydrophobic nature of most membrane proteins severely complicates their extraction, proteolysis and identification. Although detergents can be used to enhance the solubility of the membrane proteins, it is often difficult for a detergent not only to have a strong ability to extract membrane proteins, but also to be compatible with the subsequent proteolysis and mass spectrometric analysis. In this study, we made evaluation on a novel application of sodium laurate (SL) to the shotgun analysis of membrane proteomes. SL was found not only to lyse the membranes and solubilize membrane proteins as efficiently as SDS, but also to be well compatible with trypsin and chymotrypsin. Furthermore, SL could be efficiently removed by phase transfer method from samples after acidification, thus ensuring not to interfere with the subsequent CapLC-MS/MS analysis of the proteolytic peptides of proteins. When SL was applied to assist the digestion and identification of a standard protein mixture containing bacteriorhodoposin and the proteins in rat liver plasma membrane-enriched fractions, it was found that, compared with other two representative enzyme- and MS-compatible detergents RapiGest SF (RGS) and sodium deoxycholate (SDC), SL exhibited obvious superiority in the identification of membrane proteins particularly those with high hydrophobicity and/or multiple transmembrane domains.
Related JoVE Video
Comprehensive characterization of human genome variation by high coverage whole-genome sequencing of forty four Caucasians.
PLoS ONE
PUBLISHED: 02-14-2013
Show Abstract
Hide Abstract
Whole genome sequencing studies are essential to obtain a comprehensive understanding of the vast pattern of human genomic variations. Here we report the results of a high-coverage whole genome sequencing study for 44 unrelated healthy Caucasian adults, each sequenced to over 50-fold coverage (averaging 65.8×). We identified approximately 11 million single nucleotide polymorphisms (SNPs), 2.8 million short insertions and deletions, and over 500,000 block substitutions. We showed that, although previous studies, including the 1000 Genomes Project Phase 1 study, have catalogued the vast majority of common SNPs, many of the low-frequency and rare variants remain undiscovered. For instance, approximately 1.4 million SNPs and 1.3 million short indels that we found were novel to both the dbSNP and the 1000 Genomes Project Phase 1 data sets, and the majority of which (?96%) have a minor allele frequency less than 5%. On average, each individual genome carried ?3.3 million SNPs and ?492,000 indels/block substitutions, including approximately 179 variants that were predicted to cause loss of function of the gene products. Moreover, each individual genome carried an average of 44 such loss-of-function variants in a homozygous state, which would completely "knock out" the corresponding genes. Across all the 44 genomes, a total of 182 genes were "knocked-out" in at least one individual genome, among which 46 genes were "knocked out" in over 30% of our samples, suggesting that a number of genes are commonly "knocked-out" in general populations. Gene ontology analysis suggested that these commonly "knocked-out" genes are enriched in biological process related to antigen processing and immune response. Our results contribute towards a comprehensive characterization of human genomic variation, especially for less-common and rare variants, and provide an invaluable resource for future genetic studies of human variation and diseases.
Related JoVE Video
Wogonin enhances antitumor activity of tumor necrosis factor-related apoptosis-inducing ligand in vivo through ROS-mediated downregulation of cFLIPL and IAP proteins.
Apoptosis
PUBLISHED: 02-02-2013
Show Abstract
Hide Abstract
Combination of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) with other agents is a promising strategy to overcome TRAIL resistance in malignant cells. Wogonin, a flavonoid originated from Scutellaria baicalensis Georgi, has been shown to enhance TRAIL-induced apoptosis in malignant cells in in vitro studies. However, whether wogonin enhances TRAILs antitumor activity in vivo has never been studied. In this study, the effect of combination of TRAIL and wogonin was tested in a non-small-cell lung cancer xenografted tumor model in nude mice. Consistent with the in vitro study showing that wogonin sensitized A549 cells to TRAIL-induced apoptosis, wogonin greatly enhanced TRAIL-induced suppression of tumor growth, accompanied with increased apoptosis in tumor tissues as determined by TUNEL assay. The expression levels of antiapoptotic proteins including long form of cellular FLICE-like inhibitory protein (cFLIPL), X-linked inhibitor of apoptosis protein (XIAP), and cellular inhibitor of apoptosis protein 1 and 2 (cIAP-1 and cIAP-2) were markedly reduced in both cultured cells and xenografted tumor tissues after co-treatment with wogonin and TRAIL. The down-regulation of these antiapoptotic proteins was likely mediated by proteasomal degradation that involved intracellular reactive oxygen species (ROS), because wogonin robustly induced ROS accumulation and ROS scavengers butylated hydroxyanisole (BHA) and N-acetyl-L-cysteine (NAC) and the proteasome inhibitor MG132 restored the expression of these antiapoptotic proteins in cells co-treated with wogonin and TRAIL. These results show for the first time that wogonin enhances TRAILs antitumor activity in vivo, suggesting this strategy has an application potential for clinical anticancer therapy.
Related JoVE Video
Genetic variation in SIRT1 affects susceptibility of lung squamous cell carcinomas in former uranium miners from the Colorado plateau.
Carcinogenesis
PUBLISHED: 01-25-2013
Show Abstract
Hide Abstract
Epidemiological studies of underground miners suggested that occupational exposure to radon causes lung cancer with squamous cell carcinoma (SCC) as the predominant histological type. However, the genetic determinants for susceptibility of radon-induced SCC in miners are unclear. Double-strand breaks induced by radioactive radon daughters are repaired primarily by non-homologous end joining (NHEJ) that is accompanied by the dynamic changes in surrounding chromatin, including nucleosome repositioning and histone modifications. Thus, a molecular epidemiological study was conducted to assess whether genetic variation in 16 genes involved in NHEJ and related histone modification affected susceptibility for SCC in radon-exposed former miners (267 SCC cases and 383 controls) from the Colorado plateau. A global association between genetic variation in the haplotype block where SIRT1 resides and the risk for SCC in miners (P = 0.003) was identified. Haplotype alleles tagged by the A allele of SIRT1 rs7097008 were associated with increased risk for SCC (odds ratio = 1.69, P = 8.2 × 10(-5)) and greater survival in SCC cases (hazard ratio = 0.79, P = 0.03) in miners. Functional validation of rs7097008 demonstrated that the A allele was associated with reduced gene expression in bronchial epithelial cells and compromised DNA repair capacity in peripheral lymphocytes. Together, these findings substantiate genetic variation in SIRT1 as a risk modifier for developing SCC in miners and suggest that SIRT1 may also play a tumor suppressor role in radon-induced cancer in miners.
Related JoVE Video
Endoscopic ultrasound elastography for differentiating between pancreatic adenocarcinoma and inflammatory masses: a meta-analysis.
World J. Gastroenterol.
PUBLISHED: 01-17-2013
Show Abstract
Hide Abstract
To evaluate the accuracy of endoscopic ultrasound (EUS) elastography for differentiating between pancreatic ductal adenocarcinoma (PDAC) and pancreatic inflammatory masses (PIM).
Related JoVE Video
Fracture after androgen deprivation therapy among men with a high baseline risk of skeletal complications.
BJU Int.
PUBLISHED: 01-17-2013
Show Abstract
Hide Abstract
WHATS KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Receipt of androgen deprivation therapy (ADT) has been associated with an increased risk of skeletal-associated complications, such as a decrease in bone mineral density and an increase in fracture risk. Many men with pre-existing health conditions receive ADT as their primary treatment because they are considered to be inappropriate candidates for attempted curative treatments. However, several chronic health conditions, such as diabetes, rheumatoid disease and chronic liver disease, are strong predictors for osteoporosis and fractures. We undertook the present study aiming to quantify the impact of treating men with ADT who carry known risk factors for skeletal complications. Among these high-risk men, more than 58% develop at least one fracture after ADT within the 12 years of follow-up. Men who sustained a fracture within 48 months experienced an almost 40% higher risk of mortality than those who did not. Our findings suggest that treating men with a high fracture risk at baseline with long-term ADT may have serious adverse consequences.
Related JoVE Video
Metabotropic glutamate receptor 1 expression and its polymorphic variants associate with breast cancer phenotypes.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Several epidemiological studies have suggested a link between melanoma and breast cancer. Metabotropic glutamate receptor 1 (GRM1), which is involved in many cellular processes including proliferation and differentiation, has been implicated in melanomagenesis, with ectopic expression of GRM1 causing malignant transformation of melanocytes. This study was undertaken to evaluate GRM1 expression and polymorphic variants in GRM1 for associations with breast cancer phenotypes. Three single nucleotide polymorphisms (SNPs) in GRM1 were evaluated for associations with breast cancer clinicopathologic variables. GRM1 expression was evaluated in human normal and cancerous breast tissue and for in vitro response to hormonal manipulation. Genotyping was performed on genomic DNA from over 1,000 breast cancer patients. Rs6923492 and rs362962 genotypes associated with age at diagnosis that was highly dependent upon the breast cancer molecular phenotype. The rs362962 TT genotype also associated with risk of estrogen receptor or progesterone receptor positive breast cancer. In vitro analysis showed increased GRM1 expression in breast cancer cells treated with estrogen or the combination of estrogen and progesterone, but reduced GRM1 expression with tamoxifen treatment. Evaluation of GRM1 expression in human breast tumor specimens demonstrated significant correlations between GRM1 staining with tissue type and molecular features. Furthermore, analysis of gene expression data from primary breast tumors showed that high GRM1 expression correlated with a shorter distant metastasis-free survival as compared to low GRM1 expression in tamoxifen-treated patients. Additionally, induced knockdown of GRM1 in an estrogen receptor positive breast cancer cell line correlated with reduced cell proliferation. Taken together, these findings suggest a functional role for GRM1 in breast cancer.
Related JoVE Video
Genome-wide approaches for identifying genetic risk factors for osteoporosis.
Genome Med
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Osteoporosis, the most common type of bone disease worldwide, is clinically characterized by low bone mineral density (BMD) and increased susceptibility to fracture. Multiple genetic and environmental factors and gene-environment interactions have been implicated in its pathogenesis. Osteoporosis has strong genetic determination, with the heritability of BMD estimated to be as high as 60%. More than 80 genes or genetic variants have been implicated in risk of osteoporosis by hypothesis-free genome-wide studies. However, these genes or genetic variants can only explain a small portion of BMD variation, suggesting that many other genes or genetic variants underlying osteoporosis risk await discovery. Here, we review recent progress in genome-wide studies of osteoporosis and discuss their implications for medicine and the major challenges in the field.
Related JoVE Video
Bivariate genome-wide association analyses identified genes with pleiotropic effects for femoral neck bone geometry and age at menarche.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Femoral neck geometric parameters (FNGPs), which include cortical thickness (CT), periosteal diameter (W), buckling ratio (BR), cross-sectional area (CSA), and section modulus (Z), contribute to bone strength and may predict hip fracture risk. Age at menarche (AAM) is an important risk factor for osteoporosis and bone fractures in women. Some FNGPs are genetically correlated with AAM. In this study, we performed a bivariate genome-wide association study (GWAS) to identify new candidate genes responsible for both FNGPs and AAM. In the discovery stage, we tested 760,794 SNPs in 1,728 unrelated Caucasian subject, followed by replication analyses in independent samples of US Caucasians (with 501 subjects) and Chinese (with 826 subjects). We found six SNPs that were associated with FNGPs and AAM. These SNPs are located in three genes (i.e. NRCAM, IDS and LOC148145), suggesting these three genes may co-regulate FNGPs and AAM. Our findings may help improve the understanding of genetic architecture and pathophysiological mechanisms underlying both osteoporosis and AAM.
Related JoVE Video
[Changes of BDNF expression in hippocampus and serum of rats with artificial chronic obstructive pulmonary disease].
Sheng Li Xue Bao
PUBLISHED: 12-24-2011
Show Abstract
Hide Abstract
In clinical practice, we have found that cognitive impairment frequently occurs in chronic obstructive pulmonary disease (COPD) patients, but little is known about its pathophysiological mechanism. Given that brain-derived neurotrophic factor (BDNF) is affected by many factors such as smoking, infection, hypoperfusion and hypoxia, the present study was to explore the expression of BDNF in COPD rats. The rat COPD model was established by passive smoking and intratracheal instillation of lipopolysaccharide (LPS). Rats with the same age and gender ratios were divided into 4 groups: the control group (n = 6), the smoking group (n = 6), the LPS group (n = 6) and the smoking + LPS group (n = 6, COPD model). Level of BDNF in serum was measured by ELISA. And the expression of BDNF in the hippocampus was assessed using the immunohistochemistry and image analysis. The results showed that BDNF in the hippocampus and serum significantly increased in the smoking, LPS and smoking + LPS groups, compared to that in the control group. However, the expression of BDNF was less in the smoking + LPS group than that in the smoking or LPS group both in the hippocampus and serum. In conclusion, the expression of BDNF in the hippocampus and serum is highly increased in the COPD group. Smoking and intratracheal instillation of LPS induce the increase of BDNF level in the hippocampus and serum.
Related JoVE Video
Human papillomavirus type-specific prevalence in women with cervical intraepithelial neoplasm in Western China.
J. Clin. Microbiol.
PUBLISHED: 12-14-2011
Show Abstract
Hide Abstract
Human papillomavirus (HPV) type-specific prevalence was studied in 600 cases of cervical intraepithelial neoplasm in western China by GenoArray test. HPV-16 and -58 were the most prevalent types, with prevalences of 37.8% and 21.8%, respectively. HPV-18 and -45 were uncommon types. The results show different type distributions from that of other regions, which is important evidence for the selection of future genotypes in HPV vaccines in western China.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.