Mountain View
biomedical and healthCAre Data Discovery Index Ecosystem
help Advanced Search
Title: Unique gene expression profile based upon pathologic response in epithelial ovarian cancer      
dateReleased:
08-11-2011
description:
PURPOSE: We investigated whether tumor tissue obtained at diagnosis expresses a specific gene profile that is predictive of findings at second-look surgery in patients with epithelial ovarian cancer (EOC). PATIENTS AND METHODS: Tumor tissue obtained at the time of diagnosis was profiled with oligonucleotide microarrays. Class prediction analysis was performed in a training set of 24 patients who had undergone a second-look procedure. The resultant predictive signature was then tested on an independent validation set comprised of 36 patients. RESULTS: A 93-gene signature referred to as the Chemotherapy Response Profile (CRP) was identified through its association with pathologic complete response. When applied to a separate validation set, the CRP distinguished between patients with unfavorable versus favorable overall survival (median 41 months v not yet reached, respectively, log-rank P = .007), with a median follow-up of 52 months. The signature maintained independent prognostic value in multivariate analysis, controlling for other known prognostic factors such as age, stage, grade, and debulking status. There was no genetic overlap between the CRP and our previously described Ovarian Cancer Prognostic Profile (OCPP), which demonstrated similar prognostic value. The combination of the CRP and OCPP yielded better prognostic discrimination then either profile alone. Genes present in the CRP include BAX, a proapoptotic protein previously associated with chemotherapy response in ovarian cancer. CONCLUSION: Identification of a gene expression profile based on pathologic response in EOC provides independent prognostic information and offers potential insights into the mechanism of drug resistance. Efforts to identify a more tailored profile using selected genes from both the CRP and OCPP are underway. keyword(s): Correlation with outcome All microarray experiments were performed at the BIDMC Genomics Center. Ovarian cancer samples were collected at the time of primary debulking surgery and frozen at 80°C. Tumor samples were pulverized in liquid nitrogen and homogenized in Trizol solution, followed by RNA isolation, probe labeling, and Affymetrix GeneChip hybridization using standard manufacturer protocols. The dChip algorithm was used for data normalization and for generating gene expression signal values. Two outlier arrays as identified by the dChip software were excluded from further analysis.
privacy:
not applicable
aggregation:
instance of dataset
ID:
E-GEOD-31245
refinement:
raw
alternateIdentifiers:
31245
keywords:
functional genomics
dateModified:
05-02-2014
availability:
available
types:
gene expression
name:
Homo sapiens
ID:
A-GEOD-8300
name:
[HG_U95Av2] Affymetrix Human Genome U95 Version 2 Array
accessURL: https://www.ebi.ac.uk/arrayexpress/files/E-GEOD-31245/E-GEOD-31245.raw.1.zip
storedIn:
ArrayExpress
qualifier:
gzip compressed
format:
TXT
accessType:
download
authentication:
none
authorization:
none
accessURL: https://www.ebi.ac.uk/arrayexpress/files/E-GEOD-31245/E-GEOD-31245.processed.1.zip
storedIn:
ArrayExpress
qualifier:
gzip compressed
format:
TXT
accessType:
download
authentication:
none
authorization:
none
accessURL: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE31245
storedIn:
Gene Expression Omnibus
qualifier:
not compressed
format:
HTML
accessType:
landing page
primary:
true
authentication:
none
authorization:
none
abbreviation:
EBI
homePage: http://www.ebi.ac.uk/
ID:
SCR:004727
name:
European Bioinformatics Institute
homePage: https://www.ebi.ac.uk/arrayexpress/
ID:
SCR:002964
name:
ArrayExpress