Abstract 3761: Nanoliposomal c-MYC-siRNA inhibits in vivo tumor growth of cisplatin-resistant ovarian cancer

Abstract

Abstract Ovarian cancer is the deadliest of gynecological cancers in the United States. With fewer than 15% of cases diagnosed early, ovarian cancer continues to be characterized by late-stage presentation. Treatment for ovarian cancer usually involves surgical cytoreduction followed by platinum-based chemotherapy. Unfortunately, despite initial respond, more than 70% of ovarian cancer patients develop cisplatin resistance, relapse and therapeutic failure. Therefore, there is a need of novel therapies focused on targets within cancer cell survival pathways for advanced stage drug resistant ovarian cancer. Evidence indicates that activation of the oncogenic transcription factor c-MYC is involved in drug resistance. Our previous findings indicate that cisplatin-resistant ovarian cancer cells express higher c-MYC protein levels when compared to their sensitive counterparts. Importantly, targeting c-MYC with small interfering RNA (siRNA) in the cisplatin-resistant ovarian cancer cell line, A2780CP20, induced a significant cell growth arrest and inhibition of cell proliferation. Apoptosis and arrest of cell cycle progression were also observed after siRNA-based silencing of c-MYC. These results were confirmed by Western blot analysis. Furthermore, in vivo delivery of c-MYC-siRNA in a murine xenograft model of cisplatin-resistant ovarian cancer was achieved by using DOPC/PEG-2000-based nanoliposomes. A single weekly injection of nanoliposomal c-MYC-siRNA, during a four week period, decreased tumor weight and number of tumor nodules compared with a liposomal-negative control siRNA. These data propose c-MYC as a potential therapeutic target for cisplatin-resistant ovarian cancer. Citation Format: Jeyshka M. Reyes-González, Guillermo N. Armaiz, Lingegowda S. Mangala, Fatma Valiyeva, Sunila Pradeep, Anil K. Sood, Pablo E. Vivas-Mejía. Nanoliposomal c-MYC-siRNA inhibits in vivo tumor growth of cisplatin-resistant ovarian cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3761. doi:10.1158/1538-7445.AM2014-3761