Abstract 4616: Chemo-sensitisation in epithelial ovarian cancer cell lines by targeting Ankyrin Repeat Domain 1 (ANKRD1)

Abstract

Abstract Primary and acquired chemotherapy resistance remains a major challenge in the treatment of epithelial ovarian cancer and there are currently few targeted treatments that improve clinical outcome. We screened for genes that could potentially be targeted to sensitise, or re-sensitise, ovarian cancer cells to chemotherapy and identified a novel candidate, Ankyrin Repeat Domain 1 (ANKRD1), not previously described in ovarian cancer. ANKRD1 is a putative transcription factor with roles in muscle development, inflammation and response to cell stress. ANKRD1 is a target of TGF-β/Wnt signalling, and is also a binding partner of Titin (TTN) which been identified as a candidate with a high probability of carrying ‘driver’ mutations in ovarian cancer. ANKRD1 was expressed in serous ovarian cancer samples and higher tumor levels were found in patients with worse outcome (overall survival, p=0.013), (Scurr et al, Clin Cancer Res 2008; 14: 6924-32). In this study we showed that ANKRD1 levels decrease in response to cisplatin, in concert with induction of PARP cleavage and apoptosis in human ovarian cancer cell lines, COLO316, PEO14 and OAW42. We showed that decreasing ANKRD1 expression using siRNA (ON-TARGETplus Human ANKRD1 siRNA) increased cisplatin-induced apoptosis. Increased cisplatin sensitivity was associated with endoplasmic reticulum (ER) stress, evidenced by induction of GRP78, GADD153 and increased intracellular Ca2+ release. We have screened drug libraries (Prestwick library) for agents that sensitise ovarian cancer cell lines to platins, via an ANKRD1 related mechanism, and have identified several potential candidate molecules. Taken together, these results suggest that ANKRD1 plays a significant role in the regulation of apoptosis in human ovarian cancer cells, and is a potential molecular target to enhance sensitivity of ovarian cancer to chemotherapy. Citation Format: Ying Lei, Beric Ross Henderson, Catherine Emmanuel, Paul Harnett, Anna de Fazio. Chemo-sensitisation in epithelial ovarian cancer cell lines by targeting Ankyrin Repeat Domain 1 (ANKRD1). [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 4616. doi:10.1158/1538-7445.AM2014-4616