Abstract LB-51: Correlation of expression of MDR-associated genes with outcome in primary ovarian serous carcinoma

We have been developing tools to reproducibly correlate the expression of multidrug-resistance (MDR)-associated genes with response to chemotherapy in primary cancers. This study reports the results of a novel MDR gene expression analysis of primary serous carcinoma of the ovary utilizing a TaqMan Low Density Array (TLDA) chip which includes 380 previously characterized multidrug resistance (MDR)-associated genes that were initially identified in cultured cancer cells. Primary tumor samples from 133 patients from 4 sites were studied. All patients were subsequently treated with standard chemotherapy and had known clinical outcome. A 13 gene signature was identified whose expression added statistical power to the risk status of the patients based on standard clinical parameters (age, CA125, and success of surgical debulking) (log-rank statistic p=0.02). When subsets of patients with defined clinical risk were studied, we found that a subset of clinically high risk patients that had low expression of the 13 gene signature had a better outcome than would be predicted by purely clinical criteria. Similarly, clinically low risk patients with high expression of the 13 gene signature had a poorer prognosis. Since the mechanism of action of the 13 MDR genes involved in the signature are well-understood, it might be possible to devise therapeutic strategies to some of these targets with the goal of improving clinical outcome. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-51.