The hypoxia marker pimonidazole reflects a transcriptional program associated with aggressive prostate cancer.
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE55935 | GEO | 2015/01/05
SECONDARY ACCESSION(S): PRJNA241350
REPOSITORIES: GEO
Similar Datasets
Project description:We aimed to investigate the transcriptional program associated with pimonidazole staining in prostate cancer. A pimonidazole gene signature was identified that showed positive correlation to Ki67 labeling index, indicating increased proliferation in pimonidazole positive tumors. A positive correlation to clinical tumor stage and presence of lymph node metastasis was also found, consistent with associations between pimonidazole staining and clinico-pathological parameters. Moreover, the gene signature was associated with high Gleason score in a validation cohort of 59 patients and showed prognostic impact independent of Gleason score and other clinical markers in a watchful waiting validation cohort of 281 patients. Our work reveals the molecular basis of an aggressive prostate cancer phenotype reflected by pimonidazole staining, and suggests that genes involved in proliferation, DNA repair and hypoxia response contribute to this phenotype. We combined pimonidazole immunohistochemistry data and expression profiles to identify transcriptional program activated in pimonidazole positive tumors. Whole-genome gene expression profiles were determined in tumor biopsies from an investigation cohort of 46 patients, where 39 patients had received pimonidazole prior to surgery. Gene ontology analysis of 1046 genes upregulated in pimonidazole positive tumors, as defined by a staining fraction above 10%, showed significant enrichment of the biologic processes cell cycle, translation and cellular response to stress. Gene set analysis based on this result identified gene expressions in proliferation, DNA repair and hypoxia response as major parts of the transcriptional program associated with pimonidazole staining. Gene expression data of four prostate cancer cell lines were used to generate hypoxia response gene sets for this analysis. A signature of the 32 most essential genes in the program was constructed and shown to be associated with prostate cancer aggressiveness in two independent validation cohorts.
2015-01-05 | E-GEOD-55935 | biostudies-arrayexpress
Project description:PSA screening has led to enormous overtreatment of prostate cancer, due to the inability to distinguish potentially lethal disease at diagnosis. We reasoned that by identifying an mRNA signature of Gleason grade, the best predictor of prognosis, we could improve prediction of lethal disease among men with moderate Gleason 7 tumors, the most common grade, and most indeterminate in terms of prognosis. Using the complementary DNA (cDNA)M-bM-^@M-^Smediated annealing, selection, extension, and ligation assay, we measured the mRNA expression of 6,100 genes in prostate tumor tissue in the Swedish Watchful Waiting cohort (N=358) and PhysiciansM-bM-^@M-^Y Health Study (PHS; N=109). We developed an mRNA signature of Gleason comparing individuals with Gleason M-bM-^IM-$6 to those with Gleason M-bM-^IM-%8 tumors, and applied the model among Gleason 7 cases to discriminate lethal cases. We built a157-gene signature using the Swedish data that predicted Gleason with low misclassification (AUC=0.91); when this signature was tested in the PHS validation set, the discriminatory ability remained high (AUC=0.94). In men with Gleason 7 tumors, who were excluded from the model building, the signature significantly improved the prediction of lethal disease beyond knowing whether the Gleason score was 4+3 or 3+4 (p=0.006). Our expression signature and the genes identified may improve our understanding of the de-differentiation process of prostate tumors. Additionally, the signature may have clinical applications among men with Gleason 7, by further estimating their risk of lethal prostate cancer and thereby guiding therapy decisions to improve outcomes and reduce overtreatment. 198 cases from the population-based Swedish-Watchful Waiting cohort. The cohort consists of men with localized prostate cancer (clinical stage T1-T2, Mx, N0); expression profiles from tumors with Gleason M-bM-^IM-%8 (N=89) were compared to those from tumors with Gleason M-bM-^IM-$6 (N=109)
2012-04-30 | E-GEOD-37663 | biostudies-arrayexpress
Project description:PSA screening has led to enormous overtreatment of prostate cancer, due to the inability to distinguish potentially lethal disease at diagnosis. We reasoned that by identifying an mRNA signature of Gleason grade, the best predictor of prognosis, we could improve prediction of lethal disease among men with moderate Gleason 7 tumors, the most common grade, and most indeterminate in terms of prognosis. Using the complementary DNA (cDNA)–mediated annealing, selection, extension, and ligation assay, we measured the mRNA expression of 6,100 genes in prostate tumor tissue in the Swedish Watchful Waiting cohort (N=358) and Physicians’ Health Study (PHS; N=109). We developed an mRNA signature of Gleason comparing individuals with Gleason ≤6 to those with Gleason ≥8 tumors, and applied the model among Gleason 7 cases to discriminate lethal cases. We built a157-gene signature using the Swedish data that predicted Gleason with low misclassification (AUC=0.91); when this signature was tested in the PHS validation set, the discriminatory ability remained high (AUC=0.94). In men with Gleason 7 tumors, who were excluded from the model building, the signature significantly improved the prediction of lethal disease beyond knowing whether the Gleason score was 4+3 or 3+4 (p=0.006). Our expression signature and the genes identified may improve our understanding of the de-differentiation process of prostate tumors. Additionally, the signature may have clinical applications among men with Gleason 7, by further estimating their risk of lethal prostate cancer and thereby guiding therapy decisions to improve outcomes and reduce overtreatment.
2012-05-01 | GSE37663 | GEO
Project description:Current prostate cancer prognostic models are based on pre-treatment prostate-specific antigen (PSA) levels, biopsy Gleason score, and clinical staging but in practice are inadequate to accurately predict clinical disease progression. Hence, we sought to develop a molecular panel for prostate cancer progression by reasoning that molecular profiles might further improve current clinical models. We analyzed a Swedish Watchful Waiting cohort (1977â1999) with up to 30 years of clinical follow up using a novel method for gene expression profiling. This cDNA-mediated annealing, selection, ligation, and extension (DASL) method enabled the use of formalin-fixed paraffin-embedded transurethral resection of prostate (TURP) samples taken at the time of the initial diagnosis. We determined the expression profiles of 6100 genes for 281 men divided in two extreme groups: men who died of prostate cancer or developed metastases and men who survived more than 10 years without metastases (lethals and indolents, respectively). Several models using clinical and molecular features were evaluated for their ability to distinguish lethal from indolent cases. Surprisingly, none of the predictive models using molecular profiles significantly improved over models using clinical variables only. We reasoned that tumor sampling might preclude the identification of the dominant metastatic nodule. Additional computational analysis confirmed that molecular heterogeneity within both the lethal and indolent classes is widespread in prostate cancer as compared to other types of tumors. Thus the determination of the molecularly dominant tumor nodule may be limited by sampling at time of initial diagnosis, may not be present at time of initial diagnosis, or may occur as the disease progresses preventing the development of molecular biomarkers for prostate cancer progression. 281 cases from the population-based Swedish-Watchful Waiting cohort. The cohort consists of men with localized prostate cancer (clinical stage T1-T2, Mx, N0); Training set: first 186 samples; Validation cohort: remaining 95 cases from the same population.
2010-05-07 | E-GEOD-16560 | biostudies-arrayexpress
Project description:To study feasibility of gene expression profiling from FFPE tissues using NuGen amplified mRNA hybridized on Affymetrix GeneChip Human Gene 1.0 ST arrays, we designed a pilot study utilizing samples from prostate cancer cohort. We selected samples from large-scale epidemiologic studies and clinical trials representative of a wide variety of fixation times, block ages and block storage conditions. We profiled seven paired tumor and adjacent normal prostate tissue samples from three patients with Gleason score 8, one with Gleason score 7 and three with Gleason 6 disease. 11 samples had two or three technical replicates.
2014-07-01 | E-GEOD-54808 | biostudies-arrayexpress
Project description:To identify biomarkers predictive of biochemical recurrence, we isolated the RNA from 70 formalin-fixed paraffin-embedded (FFPE) radical prostatectomy specimens with known long term outcome to perform DASL expression profiling with a custom-designed panel of 522 prostate cancer relevant genes that we designed. We identified a panel of ten protein-coding genes and two miRNA genes that could be used to separate patients with and without biochemical recurrence (p < 0.001), as well as for the subset of 42 Gleason score 7 patients (p < 0.001). We performed an independent validation analysis on 40 samples and found that the biomarker panel was also significant at prediction of recurrence for all cases (p = 0.013) and for a subset of 19 Gleason score 7 cases (p = 0.010), both of which were adjusted for relevant clinical information including T-stage, PSA and Gleason score. Importantly, these biomarkers could significantly predict clinical recurrence for Gleason 7 patients. These biomarkers may increase the accuracy of prognostication following radical prostatectomy using formalin-fixed specimens. Total RNA prepared from FFPE cores from prostatectomy samples of 70 patients were used for the training phase (29 with biochemical recurrence and 41 controls). All samples were analyzed by both custom Prostate DASL of 522 genes and by Illumina miRNA microarray. Subsequently in the validation phase, samples from 40 patients were used on the same platforms (13 with biochemical recurrence and 27 controls). For the training set, 45 cases were from Sunnybrook Health Science Center (Toronto, ON), and 25 patients from Emory University. For the validation set, all samples were from Emory University. Relevant clinical metadata included are PSA, T-stage, and Gleason Score.
2011-06-01 | E-GEOD-26245 | biostudies-arrayexpress
Project description:To identify biomarkers predictive of biochemical recurrence, we isolated the RNA from 70 formalin-fixed paraffin-embedded (FFPE) radical prostatectomy specimens with known long term outcome to perform DASL expression profiling with a custom-designed panel of 522 prostate cancer relevant genes that we designed. We identified a panel of ten protein-coding genes and two miRNA genes that could be used to separate patients with and without biochemical recurrence (p < 0.001), as well as for the subset of 42 Gleason score 7 patients (p < 0.001). We performed an independent validation analysis on 40 samples and found that the biomarker panel was also significant at prediction of recurrence for all cases (p = 0.013) and for a subset of 19 Gleason score 7 cases (p = 0.010), both of which were adjusted for relevant clinical information including T-stage, PSA and Gleason score. Importantly, these biomarkers could significantly predict clinical recurrence for Gleason 7 patients. These biomarkers may increase the accuracy of prognostication following radical prostatectomy using formalin-fixed specimens. Total RNA prepared from FFPE cores from prostatectomy samples of 70 patients were used for the training phase (29 with biochemical recurrence and 41 controls). All samples were analyzed by both custom Prostate DASL of 522 genes and by Illumina miRNA microarray. Subsequently in the validation phase, samples from 40 patients were used on the same platforms (13 with biochemical recurrence and 27 controls). For the training set, 45 cases were from Sunnybrook Health Science Center (Toronto, ON), and 25 patients from Emory University. For the validation set, all samples were from Emory University. Relevant clinical metadata included are PSA, T-stage, and Gleason Score.
2011-06-01 | E-GEOD-26247 | biostudies-arrayexpress
Project description:To identify biomarkers predictive of biochemical recurrence, we isolated the RNA from 70 formalin-fixed paraffin-embedded (FFPE) radical prostatectomy specimens with known long term outcome to perform DASL expression profiling with a custom-designed panel of 522 prostate cancer relevant genes that we designed. We identified a panel of ten protein-coding genes and two miRNA genes that could be used to separate patients with and without biochemical recurrence (p < 0.001), as well as for the subset of 42 Gleason score 7 patients (p < 0.001). We performed an independent validation analysis on 40 samples and found that the biomarker panel was also significant at prediction of recurrence for all cases (p = 0.013) and for a subset of 19 Gleason score 7 cases (p = 0.010), both of which were adjusted for relevant clinical information including T-stage, PSA and Gleason score. Importantly, these biomarkers could significantly predict clinical recurrence for Gleason 7 patients. These biomarkers may increase the accuracy of prognostication following radical prostatectomy using formalin-fixed specimens. Total RNA prepared from FFPE cores from prostatectomy samples of 70 patients were used for the training phase (29 with biochemical recurrence and 41 controls). All samples were analyzed by both custom Prostate DASL of 522 genes and by Illumina miRNA microarray. Subsequently in the validation phase, samples from 40 patients were used on the same platforms (13 with biochemical recurrence and 27 controls). For the training set, 45 cases were from Sunnybrook Health Science Center (Toronto, ON), and 25 patients from Emory University. For the validation set, all samples were from Emory University. Relevant clinical metadata included are PSA, T-stage, and Gleason Score.
2011-06-01 | E-GEOD-26242 | biostudies-arrayexpress
Project description:To identify biomarkers predictive of biochemical recurrence, we isolated the RNA from 70 formalin-fixed paraffin-embedded (FFPE) radical prostatectomy specimens with known long term outcome to perform DASL expression profiling with a custom-designed panel of 522 prostate cancer relevant genes that we designed. We identified a panel of ten protein-coding genes and two miRNA genes that could be used to separate patients with and without biochemical recurrence (p < 0.001), as well as for the subset of 42 Gleason score 7 patients (p < 0.001). We performed an independent validation analysis on 40 samples and found that the biomarker panel was also significant at prediction of recurrence for all cases (p = 0.013) and for a subset of 19 Gleason score 7 cases (p = 0.010), both of which were adjusted for relevant clinical information including T-stage, PSA and Gleason score. Importantly, these biomarkers could significantly predict clinical recurrence for Gleason 7 patients. These biomarkers may increase the accuracy of prognostication following radical prostatectomy using formalin-fixed specimens. Total RNA prepared from FFPE cores from prostatectomy samples of 70 patients were used for the training phase (29 with biochemical recurrence and 41 controls). All samples were analyzed by both custom Prostate DASL of 522 genes and by Illumina miRNA microarray. Subsequently in the validation phase, samples from 40 patients were used on the same platforms (13 with biochemical recurrence and 27 controls). For the training set, 45 cases were from Sunnybrook Health Science Center (Toronto, ON), and 25 patients from Emory University. For the validation set, all samples were from Emory University. Relevant clinical metadata included are PSA, T-stage, and Gleason Score. ***This submission represents the mRNA component of the study
2011-06-01 | E-GEOD-26022 | biostudies-arrayexpress