Abstract 810: Integrative genomic and transcriptomic analysis in idenfitication of biomarkers of chemoresistance in serous epithelial ovarian cancer.

Abstract

Abstract Resistance to platinum-based chemotherapy remains a major impediment in the treatment of serous epithelial ovarian cancer. The objective of this study was to use gene expression and copy number profiling to delineate major deregulated pathways and biomarker networks associated with the development of intrinsic chemotherapy resistance with exposure to standard first-line therapy for ovarian cancer. The study cohort comprised 28 high grade serous ovarian cancer patients divided into two groups based on their varying sensitivity to first-line chemotherapy using progression free survival (PFS) as a surrogate of response. Twelve patient tumors demonstrating relative resistance to platinum based chemotherapy corresponding to shorter PFS (less than 6 months) were compared to 16 tumors from platinum-sensitive patients (PFS more than 18months). Molecular profiling was performed using Affymetrix high-resolution microarray platforms to permit global comparisons of gene expression levels and copy number profiles between tumors from the resistant group with the sensitive group. Microarray data analysis revealed a set of 227 discriminating genes of which expression levels may be influencing differential chemotherapy response between the two groups. Pathway analysis of these genes showed the,PI3K,NFkB and IGF1 networks as some of the significant networks distinguishing the chemotherapy resistant with the sensitive group. Copy number analysis performed using Nexus copy number version 6.1 revealed differences in the chromosomal regions, 4q31.22, 5q13.2, 9p24.3, 2p23.2, 16q21, 6q14.1, 7p22.3, 12p13 and Xq. Integrative copy number and gene expression profiling will delineate the drivers of chemotherapy resistance in patients undergoing standard platinum-based treatment of ovarian cancer. Future studies to validate these markers are necessary to apply this knowledge to biomarker-based clinical trials. Citation Format: Madhuri Koti, Robert J. Gooding, Paulo Nuin, Alexandria Haslehurst, Colleen Crane, Johanne Weberpals, Timothy Childs, Peter Bryson, Moyez Dharsee, Kenneth Evans, Harriet E. Feilotter, Paul C. Park, Jeremy A. Squire. Integrative genomic and transcriptomic analysis in idenfitication of biomarkers of chemoresistance in serous epithelial ovarian cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 810. doi:10.1158/1538-7445.AM2013-810