Abstract
Drug resistance is a significant challenge in the present treatment regimens of renal cell carcinoma (RCC). Our previous study confirmed that nc886 functions as an oncogene in RCC. Nevertheless, the role and underlying mechanism of nc886 in RCC drug resistance are unclear. In the present study, Sunitinib and Everolimus treatment, respectively, downregulated nc886 expression in a dose-dependent manner in all four renal cancer cell lines. Nc886 overexpression in 786-O cells and ACHN cells significantly reduced the sensitivity of cancer cells to both Sunitinib and Everolimus treatment, respectively, by promoting cell viability and inhibiting cell apoptosis, whereas nc886 silencing increased cancer cell sensitivity. In renal cancer cell line with the highest drug-resistance, 786-O cells, Sunitinib, or Everolimus treatment enhanced the cellular EMT and was further enhanced by nc886 overexpression while attenuated by nc886 silencing. In 786-O cells, nc886 overexpression significantly promoted EMT, ROCK2 phosphorylation, and β-catenin nucleus translocation under Sunitinib or Everolimus treatment. Moreover, ROCK2 silencing significantly reversed the effects of nc886 overexpression on EMT, ROCK2 phosphorylation, and β-catenin nucleus translocation, as well as drug-resistant renal cancer cell viability and apoptosis. In conclusion, it was demonstrated that nc886 promotes renal cancer cell proliferation, migration, and invasion, as demonstrated previously. nc886 also promotes renal cancer cell drug-resistance to Sunitinib or Everolimus by promoting EMT through Rock2 phosphorylation-mediated nuclear translocation of β-catenin.