[The role of autophagy in human lung cancer cell line A549 induced by Vinorelbine.].

Background: It has been proven that many kinds of drug could induce autophagy in tumor cells. The aim of the study is to verify whether Vinorelbine could induce autophagy in A549 cell lines, and to investigate the role in the effectiveness of death induced by Vinorelbine.

Methods: Cells survival rate was examined by tetrazolium bromide (MTT) colorimetry; interactive laser microscopy and flow cytometry were used to detect LC3 expression levels qualitatively and quantitatively, respectively; apoptosis rates were checked by flow cytometry; treatment of A549 cells with 3-MA and Vinorelbine, the apoptosis rates and cell death rates were examined by flow cytometry.

Results: In the early (<24 h), autophagy was evident. The crest-time appeared at (6-12) h after the cells treated with Vinorelbine. The specific inhibitor of autophagy 3-MA exerted opposite effects on Vinorelbine-induced death of A549cells: 3-MA potentiated Vinorelbine,s cytotoxicity in A549 cells when administered 1 h before Vinorelbine; while it attenuated Vinorelbine-induced death of A549 cells when treated 1 h after Vinorelbine.

Conclusions: Vinorelbine can induce autophagy in A549. In the early, autophagy could delay apoptosis. However, in the end, autophagy promoted cell death.