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Find video protocols related to scientific articles indexed in Pubmed.
EGFR as a potential therapeutic target for a subset of muscle-invasive bladder cancers presenting a basal-like phenotype.
Sci Transl Med
PUBLISHED: 07-11-2014
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Muscle-invasive bladder carcinoma (MIBC) constitutes a heterogeneous group of tumors with a poor outcome. Molecular stratification of MIBC may identify clinically relevant tumor subgroups and help to provide effective targeted therapies. From seven series of large-scale transcriptomic data (383 tumors), we identified an MIBC subgroup accounting for 23.5% of MIBC, associated with shorter survival and displaying a basal-like phenotype, as shown by the expression of epithelial basal cell markers. Basal-like tumors presented an activation of the epidermal growth factor receptor (EGFR) pathway linked to frequent EGFR gains and activation of an EGFR autocrine loop. We used a 40-gene expression classifier derived from human tumors to identify human bladder cancer cell lines and a chemically induced mouse model of bladder cancer corresponding to human basal-like bladder cancer. We showed, in both models, that tumor cells were sensitive to anti-EGFR therapy. Our findings provide preclinical proof of concept that anti-EGFR therapy can be used to target a subset of particularly aggressive MIBC tumors expressing basal cell markers and provide diagnostic tools for identifying these tumors.
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Genome-wide association study yields variants at 20p12.2 that associate with urinary bladder cancer.
Hum. Mol. Genet.
PUBLISHED: 05-26-2014
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Genome-wide association studies (GWAS) of urinary bladder cancer (UBC) have yielded common variants at 12 loci that associate with risk of the disease. We report here the results of a GWAS of UBC including 1670 UBC cases and 90 180 controls, followed by replication analysis in additional 5266 UBC cases and 10 456 controls. We tested a dataset containing 34.2 million variants, generated by imputation based on whole-genome sequencing of 2230 Icelanders. Several correlated variants at 20p12, represented by rs62185668, show genome-wide significant association with UBC after combining discovery and replication results (OR = 1.19, P = 1.5 × 10(-11) for rs62185668-A, minor allele frequency = 23.6%). The variants are located in a non-coding region approximately 300 kb upstream from the JAG1 gene, an important component of the Notch signaling pathways that may be oncogenic or tumor suppressive in several forms of cancer. Our results add to the growing number of UBC risk variants discovered through GWAS.
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Prediction of recurrence of non muscle-invasive bladder cancer by means of a protein signature identified by antibody microarray analyses.
Proteomics
PUBLISHED: 02-05-2014
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About 70% of newly diagnosed cases of bladder cancer are low-stage, low-grade, non muscle-invasive. Standard treatment is transurethral resection. About 60% of the tumors will recur, however, and in part progress to become invasive. Therefore, surveillance cystoscopy is performed after resection. However, in the USA and Europe alone, about 54 000 new patients per year undergo repeated cystoscopies over several years, who do not experience recurrence. Analysing in a pilot study resected tumors from patients with (n = 19) and without local recurrence (n = 6) after a period of 5 years by means of an antibody microarray that targeted 724 cancer-related proteins, we identified 255 proteins with significantly differential abundance. Most are involved in the regulation and execution of apoptosis and cell proliferation. A multivariate classifier was constructed based on 20 proteins. It facilitates the prediction of recurrence with a sensitivity of 80% and a specificity of 100%. As a measure of overall accuracy, the area under the curve value was found to be 91%. After validation in additional sample cohorts with a similarly long follow-up, such a signature could support decision making about the stringency of surveillance or even different treatment options.
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A siRNA screen identifies RAD21, EIF3H, CHRAC1 and TANC2 as driver genes within the 8q23, 8q24.3 and 17q23 amplicons in breast cancer with effects on cell growth, survival and transformation.
Carcinogenesis
PUBLISHED: 10-22-2013
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RNA interference has boosted the field of functional genomics, by making it possible to carry out loss-of-function screens in cultured cells. Here, we performed a small interfering RNA screening, in three breast cancer cell lines, for 101 candidate driver genes overexpressed in amplified breast tumors and belonging to eight amplicons on chromosomes 8q and 17q, investigating their role in cell survival/proliferation. This screening identified eight driver genes that were amplified, overexpressed and critical for breast tumor cell proliferation or survival. They included the well-described oncogenic driver genes for the 17q12 amplicon, ERBB2 and GRB7. Four of six other candidate driver genes-RAD21 and EIF3H, both on chromosome 8q23, CHRAC1 on chromosome 8q24.3 and TANC2 on chromosome 17q23-were confirmed to be driver genes regulating the proliferation/survival of clonogenic breast cancer cells presenting an amplification of the corresponding region. Indeed, knockdown of the expression of these genes decreased cell viability, through both cell cycle arrest and apoptosis induction, and inhibited the formation of colonies in anchorage-independent conditions, in soft agar. Strategies for inhibiting the expression of these genes or the function of the proteins they encode are therefore of potential value for the treatment of breast cancers presenting amplifications of the corresponding genomic region.
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Integrative modelling of the influence of MAPK network on cancer cell fate decision.
PLoS Comput. Biol.
PUBLISHED: 10-01-2013
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The Mitogen-Activated Protein Kinase (MAPK) network consists of tightly interconnected signalling pathways involved in diverse cellular processes, such as cell cycle, survival, apoptosis and differentiation. Although several studies reported the involvement of these signalling cascades in cancer deregulations, the precise mechanisms underlying their influence on the balance between cell proliferation and cell death (cell fate decision) in pathological circumstances remain elusive. Based on an extensive analysis of published data, we have built a comprehensive and generic reaction map for the MAPK signalling network, using CellDesigner software. In order to explore the MAPK responses to different stimuli and better understand their contributions to cell fate decision, we have considered the most crucial components and interactions and encoded them into a logical model, using the software GINsim. Our logical model analysis particularly focuses on urinary bladder cancer, where MAPK network deregulations have often been associated with specific phenotypes. To cope with the combinatorial explosion of the number of states, we have applied novel algorithms for model reduction and for the compression of state transition graphs, both implemented into the software GINsim. The results of systematic simulations for different signal combinations and network perturbations were found globally coherent with published data. In silico experiments further enabled us to delineate the roles of specific components, cross-talks and regulatory feedbacks in cell fate decision. Finally, tentative proliferative or anti-proliferative mechanisms can be connected with established bladder cancer deregulations, namely Epidermal Growth Factor Receptor (EGFR) over-expression and Fibroblast Growth Factor Receptor 3 (FGFR3) activating mutations.
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HMCan: a method for detecting chromatin modifications in cancer samples using ChIP-seq data.
Bioinformatics
PUBLISHED: 09-09-2013
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Cancer cells are often characterized by epigenetic changes, which include aberrant histone modifications. In particular, local or regional epigenetic silencing is a common mechanism in cancer for silencing expression of tumor suppressor genes. Though several tools have been created to enable detection of histone marks in ChIP-seq data from normal samples, it is unclear whether these tools can be efficiently applied to ChIP-seq data generated from cancer samples. Indeed, cancer genomes are often characterized by frequent copy number alterations: gains and losses of large regions of chromosomal material. Copy number alterations may create a substantial statistical bias in the evaluation of histone mark signal enrichment and result in underdetection of the signal in the regions of loss and overdetection of the signal in the regions of gain.
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PPAPDC1B and WHSC1L1 are common drivers of the 8p11-12 amplicon, not only in breast tumors but also in pancreatic adenocarcinomas and lung tumors.
Am. J. Pathol.
PUBLISHED: 06-28-2013
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Amplification of the 8p11-12 chromosomal region is a common genetic event in many epithelial cancers. In breast cancer, several genes within this region have been shown to display oncogenic activity. Among these genes, the enzyme-encoding genes, PPAPDC1B and WHSC1L1, have been identified as potential therapeutic targets. We investigated whether PPAPDC1B and WHSC1L1 acted as general driver genes, thereby serving as therapeutic targets in other tumors with 8p11-12 amplification. By using publicly available genomic data from a panel of 883 cell lines derived from different cancers, we identified the cell lines presenting amplification of both WHSC1L1 and PPAPDC1B. In particular, we focused on cell lines derived from lung cancer and pancreatic adenocarcinoma and found a correlation between the amplification of PPAPDC1B and WHSC1L1 with their overexpression. Loss-of-function studies based on the use of siRNA and shRNA demonstrated that PPAPDC1B and WHSC1L1 played a major role in regulating the survival of pancreatic adenocarcinoma and small-cell lung cancer-derived cell lines, both in anchorage-dependent and anchorage-independent conditions, displaying amplification and overexpression of these genes. We also demonstrated that PPAPDC1B and WHSC1L1 regulated xenograft growth in these cell lines. Finally, quantitative RT-PCR experiments after PPAPDC1B and WHSC1L1 knockdown revealed exclusive PPAPDC1B and WHSC1L1 gene targets in small-cell lung cancer and pancreatic adenocarcinoma-derived cell lines compared with breast cancer.
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New aminopyrimidine derivatives as inhibitors of the TAM family.
Eur J Med Chem
PUBLISHED: 06-19-2013
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In this study, we describe the synthesis of new pyrimidine analogs of BMS-777607, a potent and selective inhibitor of Met kinase. Inhibition of Met and Axl remained high whereas inhibition of Tyro3 and Mer decreased to some extend. The preferential moderate inhibition of the non-phosphorylated form of Abl1 of some derivatives suggests that they behave as type II inhibitors. This hypothesis was confirmed by docking studies into the structure of Met (3F82) and in a Tyro3 model where key interactions with the hinge region, the DFG-out motif and the allosteric pocket explain this inhibition.
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Rubinstein-Taybi syndrome predisposing to non-WNT, non-SHH, group 3 medulloblastoma.
Pediatr Blood Cancer
PUBLISHED: 05-26-2013
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Medulloblastomas (MB) are classified in four subgroups: the well defined WNT and Sonic Hedgehog (SHH) subgroups, and the less defined groups 3 and 4. They occasionally occur in the context of a cancer predisposition syndrome. While germline APC mutations predispose to WNT MB, germline mutations in SUFU, PTCH1, and TP53 predispose to SHH tumors. We report on a child with a Rubinstein-Taybi syndrome (RTS) due to a germline deletion in CREBBP, who developed a MB. Biological profilings demonstrate that this tumor belongs to the group 3. RTS may therefore be the first predisposition syndrome identified for non-WNT/non-SHH MB. Pediatr Blood Cancer 2014;61:383-386. © 2013 Wiley Periodicals, Inc.
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PI3K/AKT pathway activation in bladder carcinogenesis.
Int. J. Cancer
PUBLISHED: 02-21-2013
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The PI3K/AKT pathway is considered to play a major role in bladder carcinogenesis, but its relationships with other molecular alterations observed in bladder cancer remain unknown. We investigated PI3K/AKT pathway activation in a series of human bladder urothelial carcinomas (UC) according to PTEN expression, PTEN deletions and FGFR3, PIK3CA, KRAS, HRAS, NRAS and TP53 gene mutations. The series included 6 normal bladder urothelial samples and 129 UC (Ta n = 25, T1 n = 34, T2-T3-T4 n = 70). Expression of phospho-AKT (pAKT), phospho-S6-Ribosomal Protein (pS6) (one downstream effector of PI3K/AKT pathway) and PTEN was evaluated by reverse phase protein Array. Expression of miR-21, miR-19a and miR-222, known to regulate PTEN expression, was also evaluated. pAKT expression levels were higher in tumors than in normal urothelium (p < 0.01), regardless of stage and showed a weak and positive correlation with pS6 (Spearman coefficient RS = 0.26; p = 0.002). No association was observed between pAKT or pS6 expression and the gene mutations studied. PTEN expression was decreased in PTEN-deleted tumors, and in T1 (p = 0.0089) and T2-T3-T4 (p < 0.001) tumors compared to Ta tumors; it was also negatively correlated with miR-19a (RS = -0.50; p = 0.0088) and miR-222 (RS = -0.48; p = 0.0132), but not miR-21 (RS = -0.27; p = 0.18) expression. pAKT and PTEN expressions were not negatively correlated, and, on the opposite, a positive and moderate correlation was observed in Ta (RS = 0.54; p = 0.0056) and T1 (RS = 0.56; p = 0.0006) tumors. Our study suggests that PI3K/AKT pathway activation occurs in the entire spectrum of bladder UC regardless of stage or known most frequent molecular alterations, and independently of low PTEN expression.
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An essential role for decorin in bladder cancer invasiveness.
EMBO Mol Med
PUBLISHED: 02-19-2013
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Muscle-invasive forms of urothelial carcinomas are responsible for most mortality in bladder cancer. Finding new treatments for invasive bladder tumours requires adequate animal models to decipher the mechanisms of progression, in particular the way tumours interact with their microenvironment. Herein, using the murine bladder tumour cell line MB49 and its more aggressive variant MB49-I, we demonstrate that the adaptive immune system efficiently limits progression of MB49, whereas MB49-I has lost tumour antigens and is insensitive to adaptive immune responses. Furthermore, we unravel a parallel mechanism developed by MB49-I to subvert its environment: de novo secretion of the proteoglycan decorin. We show that decorin overexpression in the MB49/MB49-I model is required for efficient progression, by promoting angiogenesis and tumour cell invasiveness. Finally, we show that these results are relevant to muscle-invasive human bladder carcinomas, which overexpress decorin together with angiogenesis- and adhesion/migration-related genes, and that decorin overexpression in the human bladder carcinoma cell line TCCSUP is required for efficient invasiveness in vitro. We thus propose decorin as a new therapeutic target for these aggressive tumours.
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Evaluation of predictive models in daily practice for the identification of patients with Lynch syndrome.
Int. J. Cancer
PUBLISHED: 03-25-2011
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The optimal strategy for identifying patients with Lynch syndrome among patients with newly diagnosed colorectal cancer (CRC) is still debated. Several predictive models (e.g., MMRpredict, PREMM1,2 and MMRpro) combining personal and familial data have recently been developed to quantify the risk that a given patient with CRC carries a Lynch syndrome-causing mutation. Their clinical applicability to patients with CRC from the general population requires evaluation. We studied a consecutive series of 214 patients with newly diagnosed CRC characterized for tumor microsatellite instability (MSI), somatic BRAF mutation, MLH1 promoter methylation and mismatch repair (MMR) gene germline mutation status. The performances of the models for identifying MMR mutation carriers (8/214, 3.7%) were evaluated and compared to the revised Bethesda guidelines and a molecular strategy based on MSI testing in all patients followed by the exclusion of MSI-positive sporadic cases from mutational testing by screening for BRAF mutation and MLH1 promoter methylation. The sensitivities of the three models, at the lowest thresholds proposed, were identical (75%), with similar numbers of probands eligible for further MSI testing (almost half the patients). In our dataset, the prediction models gave no better discrimination than the revised Bethesda guidelines. Both approaches failed to identify two of the eight mutation carriers (the same two patients, aged 67 and 81 years, both with no family history). Thus, like the revised Bethesda guidelines, predictive models did not identify all patients with Lynch syndrome in our series of consecutive CRC. Our results support systematic screening for MMR deficiency in all new CRC cases.
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Gene List significance at-a-glance with GeneValorization.
Bioinformatics
PUBLISHED: 02-23-2011
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High-throughput technologies provide fundamental informations concerning thousands of genes. Many of the current research laboratories daily use one or more of these technologies and end-up with lists of genes. Assessing the originality of the results obtained includes being aware of the number of publications available concerning individual or multiple genes and accessing information about these publications. Faced with the exponential growth of publications avaliable and number of genes involved in a study, this task is becoming particularly difficult to achieve.
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A novel epigenetic phenotype associated with the most aggressive pathway of bladder tumor progression.
J. Natl. Cancer Inst.
PUBLISHED: 12-20-2010
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Epigenetic silencing can extend to whole chromosomal regions in cancer. There have been few genome-wide studies exploring its involvement in tumorigenesis.
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A prognostic DNA signature for T1T2 node-negative breast cancer patients.
Genes Chromosomes Cancer
PUBLISHED: 09-16-2010
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Predicting evolution of small node-negative breast carcinoma is a real challenge in clinical practice. The aim of this study was to search whether qualitative or quantitative DNA changes may help to predict metastasis of small node-negative breast carcinoma. Small invasive ductal carcinomas without axillary lymph node involvement (T1T2N0) from 168 patients with either good (111 patients with no event at 5 years after diagnosis) or poor (57 patients with early metastasis) outcome were analyzed with comparative genomic hybridization (CGH) array. A CGH classifier, identifying low- and high-risk groups of metastatic recurrence, was established in a training set of 78 patients, then validated, and compared with clinicopathological parameters in a distinct set of 90 patients. The genomic status of regions located on 2p22.2, 3p23, and 8q21-24 and the number of segmental alterations were defined in the training set to classify tumors into low- or high-risk groups. In the validation set, in addition to estrogen receptors and grade, this CGH classifier provided significant prognostic information in multivariate analysis (odds ratio, 3.34; 95% confidence interval 1.01-11.02; P = 4.78 × 10(-2), Wald test). This study shows that tumor DNA contains important prognostic information that may help to predict metastasis in T1T2N0 tumors of the breast.
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Mosaicism for oncogenic G12D KRAS mutation associated with epidermal nevus, polycystic kidneys and rhabdomyosarcoma.
J. Med. Genet.
PUBLISHED: 08-30-2010
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Epidermal nevus (EN) is a congenital disorder characterised by hyperpigmented epidermal thickening following a Blaschkos line. It is due to somatic mutations in either FGFR3 or PIK3CA in half of the cases, and remains of unknown genetic origin in the other half. EN is also seen as part of complex developmental disorders or in association with bladder carcinomas, also related to FGFR3 and PIK3CA mutations. Mosaic mutations of these genes have been occasionally found in syndromic EN.
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Quantitative analysis of protein complex constituents and their phosphorylation states on a LTQ-Orbitrap instrument.
J. Proteome Res.
PUBLISHED: 08-26-2010
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Cellular functions are largely carried out by noncovalent protein complexes that may exist within the cell as stable modules or as assemblies of dynamically changing composition, whose formation and decomposition are triggered in response to extracellular stimuli. The protein constituents of complexes often exhibit post-translational modifications such as phosphorylation that can impact their ability to interact with other proteins and thus to form multicomponent complexes. A complete characterization of a particular protein complex thus requires determining both, the identity of interacting proteins and their covalent modifications, in terms of attachment sites and stoichiometry. We have previously developed a protocol which identifies genuine constituents of partially purified protein complexes and concurrently determines their phosphorylation sites and levels in a single LC-MS/MS analysis performed on a MALDI-TOF/TOF instrument (Pflieger, D.; Junger, M. A.; Muller, M.; Rinner, O.; Lee, H.; Gehrig, P. M.; Gstaiger, M.; Aebersold, R. Mol. Cell. Proteomics 2008 , 7 , 326 - 346). The method combines fourplex iTRAQ labeling (isobaric tags for relative and absolute quantification) and phosphatase treatment of peptide samples derived from the tryptic digestion of isolated complexes. To test the performances of this method with nanoESI and different peptide fragmentation modes, possibly better suited for the identification of phosphorylated sequences than MALDI-TOF/TOF-MS, we have implemented it on the nanoESI-LTQ-Orbitrap instrument. The model protein beta-casein was used to optimize the conditions with respect to sensitivity and quantitative accuracy: a combination of CID fragmentation in the linear ion trap and Higher energy Collision Dissociation (HCD) appeared optimal to obtain reliable and robust identification and quantification data. The optimized conditions were then applied to identify and estimate the respective levels of phosphorylation sites on the purified, autoactivated tyrosine kinase domain of Fibroblast Growth Factor Receptor 3 (FGFR3-KD) and to analyze complexes formed around the insulin receptor substrate homologue CHICO immunopurified from Drosophila melanogaster cells that were either stimulated with insulin or left untreated. These new analyses allowed us to improve the assignment of the phosphorylation sites of some peptides previously detected by MALDI-TOF/TOF analysis and to identify additional phosphorylated sequences in CHICO and in the insulin receptor.
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Frequent genomic structural alterations at HPV insertion sites in cervical carcinoma.
J. Pathol.
PUBLISHED: 06-08-2010
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To investigate whether integration of HPV DNA in cervical carcinoma is responsible for structural alterations of the host genome at the insertion site, a series of 34 primary cervical carcinomas and eight cervical cancer-derived cell lines were analysed. DNA copy number profiles were assessed using the Affymetrix GeneChip Human Mapping 250K Sty array. HPV 16, 18 or 45 integration sites were determined using the DIPS-PCR technique. The genome status at integration sites was classified as follows: no change, amplification, transition normal/gain, normal/loss or gain/LOH. A single HPV integration site was found in 34 cases; two sites were found in seven cases; and three sites in one case (51 sites). Comparison between integration sites and DNA copy number profiles showed that the genome status was altered at 17/51 (33%) integration sites, corresponding to 16/42 cases (38%). Alterations detected were amplification in nine cases, transition normal/loss in four cases, normal/gain in three cases, and gain/LOH in one case. A highly significant association was found between genomic rearrangement and integration of HPV DNA (p < 10(-10)). Activation of the replication origin located in viral integrated sequences in a cell line derived from one of the primary cervical carcinomas induced an increase of the amplification level of both viral and cellular DNA sequences flanking the integration locus. This mechanism may be implicated in the triggering of genome amplification at the HPV integration site in cervical carcinoma. Structural alterations of the host genome are frequently observed at the integration site of HPV DNA in cervical cancer and may act in oncogenesis.
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Analysis of the copy number profiles of several tumor samples from the same patient reveals the successive steps in tumorigenesis.
Genome Biol.
PUBLISHED: 04-12-2010
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We present a computational method, TuMult, for reconstructing the sequence of copy number changes driving carcinogenesis, based on the analysis of several tumor samples from the same patient. We demonstrate the reliability of the method with simulated data, and describe applications to three different cancers, showing that TuMult is a valuable tool for the establishment of clonal relationships between tumor samples and the identification of chromosome aberrations occurring at crucial steps in cancer progression.
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Synthesis and biological evaluation of a triazole-based library of pyrido[2,3-d]pyrimidines as FGFR3 tyrosine kinase inhibitors.
Org. Biomol. Chem.
PUBLISHED: 03-11-2010
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A library of pyrido[2,3-d]pyrimidines was designed as inhibitors of FGFR3 tyrosine kinase allowing possible interactions with an unexploited region of the ATP binding-site. This library was built-up with an efficient step of click-chemistry giving easy access to triazole-based compounds bearing a large panel of substituents. Among the 27 analogues synthesized, more than half exhibited 55-89% inhibition of in vitro FGFR3 kinase activity at 2 microM and one (19g) was able to inhibit auto-phosphorylation of mutant FGFR3-K650M in transfected HEK cells.
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Molecular grade (FGFR3/MIB-1) and EORTC risk scores are predictive in primary non-muscle-invasive bladder cancer.
Eur. Urol.
PUBLISHED: 02-22-2010
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The European Organization for Research and Treatment of Cancer (EORTC) risk scores are not validated in an independent patient population. Molecular grade (mG) based on fibroblast growth factor receptor 3 (FGFR3) gene mutation status and MIB-1 expression was proposed as an alternative to pathologic grade in bladder cancer (BCa) [1].
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8p22 MTUS1 gene product ATIP3 is a novel anti-mitotic protein underexpressed in invasive breast carcinoma of poor prognosis.
PLoS ONE
PUBLISHED: 06-05-2009
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Breast cancer is a heterogeneous disease that is not totally eradicated by current therapies. The classification of breast tumors into distinct molecular subtypes by gene profiling and immunodetection of surrogate markers has proven useful for tumor prognosis and prediction of effective targeted treatments. The challenge now is to identify molecular biomarkers that may be of functional relevance for personalized therapy of breast tumors with poor outcome that do not respond to available treatments. The Mitochondrial Tumor Suppressor (MTUS1) gene is an interesting candidate whose expression is reduced in colon, pancreas, ovary and oral cancers. The present study investigates the expression and functional effects of MTUS1 gene products in breast cancer.
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A meta-analysis of the relationship between FGFR3 and TP53 mutations in bladder cancer.
PLoS ONE
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TP53 and FGFR3 mutations are the most common mutations in bladder cancers. FGFR3 mutations are most frequent in low-grade low-stage tumours, whereas TP53 mutations are most frequent in high-grade high-stage tumours. Several studies have reported FGFR3 and TP53 mutations to be mutually exclusive events, whereas others have reported them to be independent. We carried out a meta-analysis of published findings for FGFR3 and TP53 mutations in bladder cancer (535 tumours, 6 publications) and additional unpublished data for 382 tumours. TP53 and FGFR3 mutations were not independent events for all tumours considered together (OR?=?0.25 [0.18-0.37], p?=?0.0001) or for pT1 tumours alone (OR?=?0.47 [0.28-0.79], p?=?0.0009). However, if the analysis was restricted to pTa tumours or to muscle-invasive tumours alone, FGFR3 and TP53 mutations were independent events (OR?=?0.56 [0.23-1.36] (p?=?0.12) and OR?=?0.99 [0.37-2.7] (p?=?0.35), respectively). After stratification of the tumours by stage and grade, no dependence was detected in the five tumour groups considered (pTaG1 and pTaG2 together, pTaG3, pT1G2, pT1G3, pT2-4). These differences in findings can be attributed to the putative existence of two different pathways of tumour progression in bladder cancer: the CIS pathway, in which FGFR3 mutations are rare, and the Ta pathway, in which FGFR3 mutations are frequent. TP53 mutations occur at the earliest stage of the CIS pathway, whereas they occur would much later in the Ta pathway, at the T1G3 or muscle-invasive stage.
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Inhibitors of the TAM subfamily of tyrosine kinases: synthesis and biological evaluation.
Eur J Med Chem
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The TAM subfamily of Receptor Tyrosine Kinases (RTKs) contains three human proteins of therapeutical interest, Axl, Mer, and Tyro3. Our goal was to design a type II inhibitor specific for this family, i.e. able to interact with the allosteric pocket and with the hinge region of the kinase. We report the synthesis of several series of purine analogues of BMS-777607. The structural diversity of the designed inhibitors was expected to modify the interactions formed in the binding site and consequently to modulate their selectivity profiles. The most potent inhibitor 6g exhibits Kds of 39, 42, 65 and 200 nM against Axl, Mer, Met and Tyro3 respectively. Analysis of the affinity of 6g for active and inactive forms of Abl1, an RTK protein that does not belong to the TAM subfamily, together with the binding modes of 6g predicted by docking studies, indicates that 6g displays some selectivity for the TAM family and may act as a type II inhibitor.
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Deregulation of Rab and Rab effector genes in bladder cancer.
PLoS ONE
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Growing evidence indicates that Rab GTPases, key regulators of intracellular transport in eukaryotic cells, play an important role in cancer. We analysed the deregulation at the transcriptional level of the genes encoding Rab proteins and Rab-interacting proteins in bladder cancer pathogenesis, distinguishing between the two main progression pathways so far identified in bladder cancer: the Ta pathway characterized by a high frequency of FGFR3 mutation and the carcinoma in situ pathway where no or infrequent FGFR3 mutations have been identified. A systematic literature search identified 61 genes encoding Rab proteins and 223 genes encoding Rab-interacting proteins. Transcriptomic data were obtained for normal urothelium samples and for two independent bladder cancer data sets corresponding to 152 and 75 tumors. Gene deregulation was analysed with the SAM (significant analysis of microarray) test or the binomial test. Overall, 30 genes were down-regulated, and 13 were up-regulated in the tumor samples. Five of these deregulated genes (LEPRE1, MICAL2, RAB23, STXBP1, SYTL1) were specifically deregulated in FGFR3-non-mutated muscle-invasive tumors. No gene encoding a Rab or Rab-interacting protein was found to be specifically deregulated in FGFR3-mutated tumors. Cluster analysis showed that the RAB27 gene cluster (comprising the genes encoding RAB27 and its interacting partners) was deregulated and that this deregulation was associated with both pathways of bladder cancer pathogenesis. Finally, we found that the expression of KIF20A and ZWINT was associated with that of proliferation markers and that the expression of MLPH, MYO5B, RAB11A, RAB11FIP1, RAB20 and SYTL2 was associated with that of urothelial cell differentiation markers. This systematic analysis of Rab and Rab effector gene deregulation in bladder cancer, taking relevant tumor subgroups into account, provides insight into the possible roles of Rab proteins and their effectors in bladder cancer pathogenesis. This approach is applicable to other group of genes and types of cancer.
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CDKN2A homozygous deletion is associated with muscle invasion in FGFR3-mutated urothelial bladder carcinoma.
J. Pathol.
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The gene cyclin-dependent kinase inhibitor 2A (CDKN2A) is frequently inactivated by deletion in bladder carcinoma. However, its role in bladder tumourigenesis remains unclear. We investigated the role of CDKN2A deletion in urothelial carcinogenesis, as a function of FGFR3 mutation status, a marker for one of the two pathways of bladder tumour progression, the Ta pathway. We studied 288 bladder carcinomas: 177 non-muscle-invasive (123 Ta, 54 T1) and 111 muscle-invasive (T2-4) tumours. CDKN2A copy number was determined by multiplex ligation-dependent probe amplification, and FGFR3 mutations by SNaPshot analysis. FGFR3 mutation was detected in 124 tumours (43.1%) and CDKN2A homozygous deletion in 56 tumours (19.4%). CDKN2A homozygous deletion was significantly more frequent in FGFR3-mutated tumours than in wild-type FGFR3 tumours (p = 0.0015). This event was associated with muscle-invasive tumours within the FGFR3-mutated subgroup (p < 0.0001) but not in wild-type FGFR3 tumours. Similar findings were obtained for an independent series of 101 bladder carcinomas. The impact of CDKN2A deletions on recurrence-free and progression-free survival was then analysed in 89 patients with non-muscle-invasive FGFR3-mutated tumours. Kaplan-Meier survival analysis showed that CDKN2A losses (hemizygous and homozygous) were associated with progression (p = 0.0002), but not with recurrence, in these tumours. Multivariate Cox regression analysis identified CDKN2A loss as a predictor of progression independent of stage and grade. These findings highlight the crucial role of CDKN2A loss in the progression of non-muscle-invasive FGFR3-mutated bladder carcinomas and provide a potentially useful clinical marker for adapting the treatment of such tumours, which account for about 50% of cases at initial clinical presentation.
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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.

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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.