Background: To date, few studies have systematically characterized microarray gene expression signal performance with degraded RNA from formalin-fixed paraffin-embedded (FFPE) specimens in comparison to intact RNA from unfixed fresh-frozen (FF) specimens.
Quantitative expression profiling in formalin-fixed paraffin-embedded samples by affymetrix microarrays.
Specimen part, Subject
View SamplesAlveolar rhabdomyosarcomas (ARMS) are aggressive soft-tissue sarcomas affecting children and young adults. Most ARMS tumors express the PAX3-FKHR or PAX7-FKHR (PAX-FKHR) fusion genes resulting from the t(2;13) or t(1;13) chromosomal translocations, respectively. However, up to 25% of ARMS tumors are fusion negative, making it unclear whether ARMS represent a single disease or multiple clinical and biological entities with a common phenotype. To test to what extent PAX-FKHR determine class and behavior of ARMS, we used oligonucleotide microarray expression profiling on 139 primary rhabdomyosarcoma tumors and an in vitro model. We found that ARMS tumors expressing either PAX-FKHR gene share a common expression profile distinct from fusion-negative ARMS and from the other rhabdomyosarcoma variants. We also observed that PAX-FKHR expression above a minimum level is necessary for the detection of this expression profile. Using an ectopic PAX3-FKHR and PAX7-FKHR expression model, we identified an expression signature regulated by PAX-FKHR that is specific to PAX-FKHR-positive ARMS tumors. Data mining for functional annotations of signature genes suggested a role for PAX-FKHR in regulating ARMS proliferation and differentiation. Cox regression modeling identified a subset of genes within the PAX-FKHR expression signature that segregated ARMS patients into three risk groups with 5-year overall survival estimates of 7%, 48%, and 93%. These prognostic classes were independent of conventional clinical risk factors. Our results show that PAX-FKHR dictate a specific expression signature that helps define the molecular phenotype of PAX-FKHR-positive ARMS tumors and, because it is linked with disease outcome in ARMS patients, determine tumor behavior.
Identification of a PAX-FKHR gene expression signature that defines molecular classes and determines the prognosis of alveolar rhabdomyosarcomas.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesDuctal carcinoma in situ (DCIS) is a precursor lesion that can give rise to invasive breast cancer (IBC). It has been proposed that both the nature of the lesion and the tumor microenvironment play key roles in progression to IBC. Here, laser capture microdissected tissue samples from epithelium and stroma in normal breast, pure DCIS, and pure IBC were employed to define key gene expression profiles associated with disease progression.
Progression of ductal carcinoma in situ to invasive breast cancer is associated with gene expression programs of EMT and myoepithelia.
Specimen part, Subject
View SamplesNeuroendocrine prostate cancer (NEPC) is rare historically but may be increasingin prevalence as patients potentially develop resistance to contemporary anti-androgen treatment through a neuroendocrine phenotype. Diagnosis can be straightforward when classic morphological features are accompanied by a prototypical immunohistochemistry profile, however there is increasing recognition of disease heterogeneity and hybrid phenotypes. In the primary setting, small cell prostatic carcinoma (SCPC) is frequently admixed with adenocarcinomas that may be clonally related, while a small fraction of SCPCs express markers typical of prostatic adenocarcinoma. Gene expression patterns may eventually help elucidate the biology underlying equivocal cases with discordant IHC, however studies to date have focused on prototypical cases and been based on few patients due to disease rarity.
Gene expression signatures of neuroendocrine prostate cancer and primary small cell prostatic carcinoma.
Subject
View SamplesTo determine whether adding Decipher to standard risk stratification tools (CAPRA-S and Stephenson nomogram) improves accuracy in prediction of metastatic disease within 5 years after surgery in men with adverse pathologic features after RP.
A genomic classifier improves prediction of metastatic disease within 5 years after surgery in node-negative high-risk prostate cancer patients managed by radical prostatectomy without adjuvant therapy.
Age
View SamplesYB-1 controls epithelial-mesenchymal transitions by restricting translation of growth-related mRNAs and enabling expression of EMT-inducing transcription factors. We used microarrays to characterize the direct transcriptional and indirect translational regulation of mRNAs by exogenous YB-1 in breast cancer cell lines.
Translational activation of snail1 and other developmentally regulated transcription factors by YB-1 promotes an epithelial-mesenchymal transition.
No sample metadata fields
View SamplesThe dataset consists of 266 NCCN very low/low or favorable-intermediate risk PCa patients who underwent diagnostic prostate biopsy between 2000 and 2014 and were treated with RP in six community or academic practices: University of Calgary, Cedars-Sinai, Spectrum Health, Cleveland Clinic, MD Anderson Cancer Center and Johns Hopkins. All patients had complete tumor pathology from biopsy and prostatectomy. Low risk PCa was defined as T1c or cT2a, and Gleason score (GS) 6, and PSA < 10ng/ml and favorable-intermediate risk was no greater than predominant GS 3 and percent positive biopsy cores < 50%, and either cT2b-cT2c or PSA 10-20ng/ml.
Validation of the Decipher Test for predicting adverse pathology in candidates for prostate cancer active surveillance.
Age, Specimen part
View SamplesPurpose: Selecting muscle-invasive bladder cancer patients for adjuvant therapy is currently based on clinical variables with limited power. We hypothesized that genomic-based signatures can outperform clinical models to identify patients at higher risk. Method:Transcriptome-wide expression profiles were generated using 1.4 million feature-arrays on archival tumors from 225 patients who underwent radical cystectomy and had muscle-invasive and/or node-positive bladder cancer. A 15-feature GC was developed on the discovery set with area under curve (AUC) of 0.77 in the validation set.
Discovery and validation of novel expression signature for postcystectomy recurrence in high-risk bladder cancer.
Specimen part
View SamplesDuchenne Muscular Dystrophy (DMD) is a fatal muscle wasting disorder caused by dystrophin deficiency. Previous work suggested that increased expression of the dystrophin-related protein utrophin in the mdx mouse model of DMD can prevent dystrophic pathophysiology. Physiological tests showed that the transgenic mouse muscle functioned in a way similar to normal muscle. More recently, it has become possible to analyse disease pathways using microarrays, a sensitive method to evaluate the efficacy of a therapeutic approach. We thus examined the gene expression profile of mdx mouse muscle compared to normal mouse muscle and compared the data with that obtained from the transgenic line expressing utrophin. The data confirm that the expression of utrophin in the mdx mouse muscle results in a gene expression profile virtually identical to that seen for the normal mouse. This study confirms that a strategy to up-regulate utrophin is likely to be effective in preventing the disease.
Microarray analysis of mdx mice expressing high levels of utrophin: therapeutic implications for dystrophin deficiency.
No sample metadata fields
View SamplesTo test the hypothesis that a genomic classifier (GC) would predict biochemical failure (BF) and distant metastasis (DM) in men receiving radiation therapy (RT) after radical prostatectomy (RP).
The Landscape of Prognostic Outlier Genes in High-Risk Prostate Cancer.
Age
View Samples