Abstract 1939: Identification of microRNAs related to chemosensitivity in ovarian cancer using Next Generation Sequencing

Ovarian cancer is the most common cause of gynecologic malignancy related mortality in women. The combination of tumor reductive surgery and chemotherapy is the main therapeutic strategy for ovarian cancer. However, especially in the most of advanced cases, complete site reduction is impossible to achieve. In those cases, the sensitivity to chemotherapy strongly affects their prognoses. MicroRNAs (miRNAs), which are approximately 22-nucleotide non-coding RNAs, regulate protein expression by translational inhibition and degradation of their target mRNAs. The expression of miRNAs is dysregulated in various types of cancers, suggesting that miRNAs are involved in carcinogenesis and cancer progression. The purpose of present work was to identify miRNAs which are related to chemo-sensitivity in ovarian cancer. Using Next Generation Sequencing (NGS), miRNA profiling was performed in 38 advanced high-grade serous ovarian cancers (HGSOCs). RNAs including miRNAs were procured from the epithelial component of the laser microdissected tumor tissue removed from patients undergoing primary surgery without neo-adjuvant chemotherapy. A total of 1935 miRNAs and miRNA variants were detected by NGS and normalized expression data of each miRNAs and miRNA variants were used for further analyses. Comparing the copy numbers of each miRNAs between chemo-refractory group (patients with disease progression in the period of first line chemotherapy, n=7) and chemo-sensitive group (patients with disease progression in more than 6 months after completion of first line chemotherapy, n=13) by Mann-Whitney U test, 77 miRNAs and miRNA variants were found to be dysregulated with significant differences (p Our results strongly suggest that mir-625-3p might be a prognostic marker that can be used to predict chemo-sensitivity in patients with HGSOC. Further characterization of mir-625-3p as a therapeutic target for HGSOC is in progress. Citation Format: Tetsushi Tsuruga, Chi Lam Au Yeung, Cecilia S. Leung, Tsz-Lun Yeung, Kwong K. Wong, Rosemarie Schmandt, Ngai Na Co, Karen H. Lu, Samuel Mok. Identification of microRNAs related to chemosensitivity in ovarian cancer using Next Generation Sequencing. [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 1939. doi:10.1158/1538-7445.AM2013-1939