Crotoxin induces apoptosis and autophagy in human lung carcinoma cells in vitro via activation of the p38 MAPK signaling pathway  

作　　者：Rong HAN Hui LIANG Zheng-hong QIN Chun-yu LIU 

机构地区：[1]College of Pharmaceutical Science, Soochow University, Suzhou 215123, China

出　　处：《Acta Pharmacologica Sinica》2014年第10期1323-1332,共10页中国药理学报（英文版）

摘　　要：Aim： Crotoxin （CrTX） is the primary toxin in South American rattlesnake （Crotalus durissus terrificus） venom, and exhibits antitumor and other pharmacological actions in vivo and in vitro. Here, we investigated the molecular mechanisms of the antitumor action of CrTX in human lung carcinoma cells in vitro. Methods： Human lung squamous carcinoma SK-MES-1 cells were tested. The cytotoxicity of CrTX was evaluated in both MTT and colony formation assays. Cell cycle was investigated with flow cytometry. Cell apoptosis was studied with Hoechst 33258 and Annexin V-FITC staining. The levels of relevant proteins were analyzed using Western blot assays. Results： CrTX （25, 50, 100 pmol/L） inhibited the growth and colony formation of SK-MES-1 cells in dose- and time-dependent manners. CrTX increased the proportion of S phase cells and dose-dependently induced cell apoptosis, accompanied by down-regulating the expression of proliferating cell nuclear antigen （PCNA）, and increasing the level of cleaved caspase-3. Furthermore, CrTX dose- dependently increased the expression of autophagy-related proteins LC3-11 and beclin 1, and decreased the level of p62 in the cells. Moreover, CrTX （50 pmol/L） significantly increased p38MAPK phosphorylation in the cells. Pretreatment of the cells with SB203580, a specific inhibitor of p38MAPK, blocked the inhibition of CrTX on cell proliferation, as well as CrTX-induced apoptosis and cleaved caspase-3 expression. Conclusion： The p38MAPK signaling pathway mediates CrTX-induced apoptosis and autophagy of human lung carcinoma SK-MES-1 cells in vitro.Aim： Crotoxin （CrTX） is the primary toxin in South American rattlesnake （Crotalus durissus terrificus） venom, and exhibits antitumor and other pharmacological actions in vivo and in vitro. Here, we investigated the molecular mechanisms of the antitumor action of CrTX in human lung carcinoma cells in vitro. Methods： Human lung squamous carcinoma SK-MES-1 cells were tested. The cytotoxicity of CrTX was evaluated in both MTT and colony formation assays. Cell cycle was investigated with flow cytometry. Cell apoptosis was studied with Hoechst 33258 and Annexin V-FITC staining. The levels of relevant proteins were analyzed using Western blot assays. Results： CrTX （25, 50, 100 pmol/L） inhibited the growth and colony formation of SK-MES-1 cells in dose- and time-dependent manners. CrTX increased the proportion of S phase cells and dose-dependently induced cell apoptosis, accompanied by down-regulating the expression of proliferating cell nuclear antigen （PCNA）, and increasing the level of cleaved caspase-3. Furthermore, CrTX dose- dependently increased the expression of autophagy-related proteins LC3-11 and beclin 1, and decreased the level of p62 in the cells. Moreover, CrTX （50 pmol/L） significantly increased p38MAPK phosphorylation in the cells. Pretreatment of the cells with SB203580, a specific inhibitor of p38MAPK, blocked the inhibition of CrTX on cell proliferation, as well as CrTX-induced apoptosis and cleaved caspase-3 expression. Conclusion： The p38MAPK signaling pathway mediates CrTX-induced apoptosis and autophagy of human lung carcinoma SK-MES-1 cells in vitro.

关 键 词：human lung carcinoma snake venom CROTOXIN cell cycle arrest APOPTOSIS AUTOPHAGY caspase-3 proliferating cell nuclearantigen p38 MAPK SB203580 

分 类 号：Q257[生物学—细胞生物学] Q782