Arid1a Suppresses Akt/Nras-Driven Hepatocarcinogenesis In Mice

The SWI/SNF chromatin remodeling complexes are increasingly appreciated for their roles in carcinogenesis. Recent progress in human cancer genomic sequencing revealed that chromatin remodeling complexes are frequently targeted by cancer mutations, particularly in hepatocellular carcinomas (HCC). However, their precise role in HCC remains controversial and incompletely understood. AKT and NRAS are two major liver oncogenes that promote aberrant growth, metabolism and proliferation of hepatocytes, leading to initiation and development of HCC. Here, we investigated the role of Arid1a, one of the most mutated subunits of the SWI/SNF chromatin-remodeling complex across all human cancers, in hepatocarcinogenesis. To this end, we used Akt/NRas-driven mouse liver cancer model generated by hydrodynamic transfection (HDT). We found that overexpression of Arid1a strongly attenuated Akt/NRas-driven liver tumorigenesis and prolonged survival of animals. Conversely, knockdown of Arid1a accelerated Akt/NRas-driven liver cancer development and shortened survival in mice. We further showed that Arid1a antagonized activation of multiple molecular pathways downstream of Akt/NRas. Conclusion: Arid1a acts as a tumor suppressor in the Akt/NRas mouse HCC model. These new findings provide in vivo evidence for a tumor suppressive role of Arid1a-dependent chromatin remodeling in Akt/NRas-driven hepatocarinogenesis. Citation Format: Shanshan Zhang, Yufeng Zhou, Di Cao, Qiannan Ren, Meiyin Zhang, Shijuan Mai, Huiyun Wang. Arid1a suppresses Akt/NRas-driven hepatocarcinogenesis in mice [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4721.