Shikonin regulates invasion and autophagy of cultured colon cancer cells by inhibiting yes-associated protein

Abstract

Colon cancer is a common malignancy, and its morbidity and mortality have been increasing in recent years in China. Shikonin (Shi), a naturally occurring naphthoquinone, exhibits anticancer activity. However, the mechanisms of action of Shi remain unclear. The aim of the present study was to investigate the antitumor mechanism of Shi in colon cancer cells. The effects of different Shi concentrations on the viability of colon cancer cells using MTT, colony formation and wound-healing assays were assessed. Western blot analysis was performed to detect the expression of LC3-II, p62. Shi effectively suppressed viability and cell migration, and induced autophagy in colon cancer cells. Yes-associated protein (YAP) increases cell viability, and inhibits cell apoptosis and cell contact. Expression of YAP is downregulated by Shi. The cytotoxic effects of Shi were further investigated on YAP overexpression and on YAP knockout cell lines. The findings revealed that Shi suppressed the viability and induced autophagy of colon cancer cells. Additionally, YAP expression reversed the effects of Shi. The results of the present study suggest that Shi may be a promising anticancer treatment for colon cancer, and YAP may be a potential diagnostic marker for colon cancer.