Abstract 2054: Cerivastatin overcomes the acquired resistance to crizotinib in EML4-ALK positive non-small cell lung cancer by controlling YAP activation

Abstract

Abstract Crizotinib is highly effective in patients with non-small cell lung cancer (NSCLC) harboring the echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) fusion. However, its efficacy has been limited by the development of acquired resistance, and the mechanisms of such resistance remain largely unknown. Herein, we investigated a possible candidate for circumventing the acquired resistance to crizotinib. We established a model of acquired resistance to crizotinib (H3122-CR) by exposing EML4-ALK-positive H3122 lung cancer cells to increasing doses of crizotinib, and performed MTT screening using a library of FDA (Food and Drug Administration)-approved drugs composed of a collection of 640 clinically used compounds. Our MTT screening identified that cerivastatin, a drug targeting 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase, significantly inhibited the cell growth in H3122-CR cells, which was completely restored by addition of geranylgeranyl pyrophosphate (GGPP), a key metabolite of mevalonate pathway. We also found that yes-associated protein (YAP), a major effector of the Hippo tumor suppressor pathway, was robustly accumulated in nucleus with a concomitant decrement of YAP phosphorylation in H3122-CR cells compared to parental cells. Importantly, inhibition of geranylgeranylation (GGylation) by GGTI-298 or cerivastatin markedly increased YAP phosphorylation, led to cytoplasmic translocation of YAP, and subsequently induced YAP inactivation. Moreover, the enrichment of EGFR signaling pathway and cell cycle signature including transcriptional targets of YAP was enhanced in H3122-CR cells, whose induction contributed YAP-mediated resistance to crizotinib. Inhibition of YAP function with siRNA or verteporfin as a YAP inhibitor greatly abrogated cell growth of H3122-CR cells by modulating cell cycle regulators and EGFR activation. Finally, we confirmed up-regulation of nuclear YAP expression in crizotinib-acquired resistant patient derived tumor xenograft (PDTX) models established from EML4-ALK positive NSCLC patients. Collectively, our findings define the GGylation-mediated YAP transcriptional activation as a new mechanism of resistance to crizotinib, providing a rationale for further exploring statins as a possible anticancer agent to overcome the acquired resistance to crizotinib in EML4-ALK positive NSCLC cells. Citation Format: Miran Yun, Hun Mi Choi, Kyoung Ho Pyo, Byoung Chul Cho. Cerivastatin overcomes the acquired resistance to crizotinib in EML4-ALK positive non-small cell lung cancer by controlling YAP activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2054. doi:10.1158/1538-7445.AM2017-2054