Effect of autophagy on paclitaxel-induced CaSki cell death.

Abstract

To observe the effect of autophagy on paclitaxel-induced CaSki cell death through the regulation of the expression of autophagy gene Beclin1, and to explore the interaction and relationship between autophagy and apoptosis. Eukaryotic expression vector pcDNA3.1-Beclin1 and RNA interference vector pSUPER-Beclin1 were transfected into human cervical cancer CaSki cells in vitro and screened for stable expression cell lines. The formation of autophagic vacuoles was observed with an electronic microscope. The expression of Beclin1 and LC3 was measured by Western blot. After being treated with paclitaxel, the change of cell proliferation was assessed by MTT assay, the percentage of apoptotic cells and autophagic cells were analyzed by flow cytometry. A lot of autophagic vacuoles were observed in pcDNA3.1-Beclin1 cells by electronic microscopy. Beclin1 and LC3 protein expression was up-regulated in CaSki cells transfected with pcDNA3.1-Beclin1, and was inhibited in cells transfected with pSUPER-Beclin1. MTT assay revealed the survival rate of CaSki cells was significantly decreased after being transfected with pcDNA3.1-Beclin1. After being treated with paclitaxel, the percentages of apoptotic cells and autophagic cells were both increased in pcDNA3.1-Beclin1 group compared with that of the blank control group especially the increase of apoptosis was particularly evident. Autophagy and apoptosis have different roles in the process of paclitaxel-induced cervical cancer CaSki cell line death. Overexpression of Beclin1 in CaSki cells may enhance the apoptosis induced by paclitaxel.