Abstract

 

Dihydroartemisinin (DHA) is reported to possess evident anticancer activity to an abundance of cancers, whereas the pharmacologic effect of DHA on HBV-positive hepatocellular carcinoma (HCC) still remains unknown. In the present study, we uncovered the role and the underlying mechanisms of DHA in its proliferation inhibition of HepG2.2.15 cell line. We found that DHA effectively inhibited HepG2.2.15 HCC cell line proliferation in vivo and in vitro, and also reduced its migration and tumorigenicity capacity. Mechanisms study showed that DHA induced cellular senescence and up-regulated the expression of proteins in DNA damage response, such as p-ATM, p-ATR, -H2AX, P53 and P21. DHA could also induce autophagy which presented green LC3 puncta gathered together and LC3/LC3ratio increased through AKT-mTOR pathway suppression. Further mechanisms study showed that DHA-induced autophagy was not linked to senescence or cell death, and TPP1 overexpression could not protect DHA-induced anticancer activity. Moreover, DHA down-regulated telomere shelterin TPP1 expression and genetic knockdown of TPP1 caused the similar phenotypes and mechanisms as DHA. These results demonstrated that DHA might inhibit HepG2.2.15 cells proliferation through inducing cellular senescence and autophagy.