Project description:The Japanese Serous Ovarian Cancer Study Group Advanced-stage ovarian cancer is one of the most lethal gynecologic malignancies. To improve prognosis of patients with ovarian cancers, a predictive biomarkers leading to personalized treatments are required. In this large-scale cross-platform study of six microarray datasets consisting of 1054 ovarian cancer patients, we developed a novel risk classification system based on a 126-gene expression signature for predicting overall survival by applying elastic net7 and 10-fold cross validation to a Japanese dataset A (n = 260). We further validated its predictive ability with the five other datasets using multivariate analysis. Also, through gene ontology and pathway analyses of 1109 high-risk ovarian cancer specific transcripts, we identified a significant reduction of expression of immune-response related genes, especially on the antigen presentation pathway. Furthermore, an immunohistochemical analysis demonstrated that the number of CD8 T lymphocytes infiltrating into tumor tissue was significantly decreased in high-risk ovarian cancers. These predictive biomarkers based on the 126-gene expression signature will identify high-risk ovarian cancer patients who need novel immune-activating therapeutic approaches, leading to improved outcomes for such patients. Two hundred sixty patients who were diagnosed as advanced-stage high-grade serous ovarian cancer were analyzed in this study. Microaray data from 10 patients who were diagnosed as advanced-stage high-grade serous ovarian cancer were analyzed to investigate coefficient of correlation in each probes between Agilent Whole Human Genome Oligo Microarray and Affymetrix HG-U133Plus2.0.

2012-03-01 | E-GEOD-32062 | biostudies-arrayexpress