Deacetylation of miRNA-34a and miRNA-449 induce epithelial-mesenchymal transition and acquired resistance to ALK inhibitors

Treatment with ALK tyrosine kinase inhibitors often elicits profound initial antitumor responses in ALK fusion-positive patients with lung adenocarcinoma. However, patients invariably develop acquired resistance to ALK inhibitors. In this study, we aimed to identify molecular events that limit the durable response to ALK inhibition using genetic and epigenetic approaches. To identify novel mechanisms of acquired resistance to ALK inhibitors, we established in vivo and in vitro models of acquired resistance to ceritinib and crizotinib using H3122 and H2228 cells. For in vivo model, mice with established H3122-derived tumors were treated with four doses of ceritinib (control, 75mg/kg, 87.5mg/kg, 100mg/kg) to derive ceritinib-resistant tumors. For in vivo model, mice with established H3122-derived tumors were treated with four doses of ceritinib (control, 75mg/kg, 87.5mg/kg, 100mg/kg) to derive ceritinib-resistant tumors. Xenograft tumors showed initial dose-dependent decrease in tumor volume and subsequently developed acquired resistance within 24-108 days.