title: Oleanolic acid induced autophagic cell death in hepatocellular carcinoma cells via PI3K/Akt/mTOR and ROS-dependent pathway.
abstract: Oleanolic acid (OA) has a wide variety of bioactivities such as hepatoprotective, anti-inflammatory and anti-cancer activity and is used for medicinal purposes in many Asian countries. In the present study, the effect of OA on induction of autophagy in human hepatocellular carcinoma HepG2 and SMC7721 cells and the related mechanisms were investigated. MTT assay showed that OA significantly inhibited HepG2 and SMC7721 cells growth. OA treatment enhanced formation of autophagic vacuoles as revealed by monodansylcadaverine (MDC) staining. At the same time, increasing punctuate distribution of microtubule-associated protein 1 light chain 3 (LC3) and an increasing ratio of LC3-II to LC3-I were also triggered by OA incubation. In addition, OA-induced cell death was signifi cantly inhibited by autophagy inhibitors 3-methyladenine (3-MA) and chloroquine (CQ) pretreatment. And we found out that OA can suppress the PI3K/Akt1/mTOR signaling pathway. Furthermore, our data suggested that OA-triggered autophagy was ROS-dependent as demonstrated by elevated cellular ROS levels by OA treatment. When ROS was cleared by N-acetylcysteine (NAC), OA-induced LC3-II convertsion and cell death were all reversed. Taken together, our results suggest that OA exerts anticancer eff ect via autophagic cell death in hepatocellular carcinoma.
authors.affiliation: Department of General Surgery, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of General Surgery, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China.
authors.forename: Qingwei
authors.initials: Q
authors.lastname: Song
authors.affiliation: Department of General Surgery, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China.
authors.forename: Dianhe
authors.initials: D
authors.lastname: Hu
authors.affiliation: Department of General Surgery, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China.
authors.forename: Xiaohu
authors.initials: X
authors.lastname: Zhuang
authors.affiliation: Department of General Surgery, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China.
authors.forename: Shengcai
authors.initials: S
authors.lastname: Yu
authors.affiliation: Department of Basic Medical, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China.
authors.forename: Dacai
authors.initials: D
authors.lastname: Teng
keywords: Autophagy; Hepatocellular carcinoma; Oleanolic acid; ROS; mTOR