摘要：

Objective To investigate the role of apoptosis stimulating p53 binding protein 2( ASPP2)-induced p53-dependent and p53-independent autophagy inhibition in apoptosis-promoting function of oxaliplatin( OXA). Methods According to different treatments,HCT116( p53- /-) cells were divided into 6 groups: rapamycin combined with ASPP2 group,ASPP2 group,p53 group,ASPP2 combined with p53 group,OXA combined with 3-methyladenine( 3-MA) group,control group( OXA treatment or starvation without OXA treatment). When the level of apoptosis was detected,green fluorescent protein-advirus( GFP-Ad) group and rapamycin group were supplemented as controls. Cells were transfected with GFP-microtubuleassociated protein 1 light chain 3( GFP-LC3) plasmid,and LC3-expressing cells were calculated under a fluorescent microscope. Expressions of autophagy-related molecules were detected by Western blotting. Cells were subjected to annexin V-FITC / PI staining and apoptosis was assessed by flow cytometry. Results The 3-MA group showed the same inhibitory ability on autophagy with the ASPP2 group,and both of them were able to promote OXA or starvation-induced apoptosis,but the cell apoptosis rate in the 3-MA group was lower than that of the ASPP2 group. Rapamycin combined with ASPP2 still promoted OXA or starvation-induced apoptosis,and the apoptosis rate was also lower than that of the ASPP2 group.However,rapamycin counteracted effectively the inhibitory effect of ASPP2 on autophagy. Conclusion OXA can induce autophagy of colorectal cancer cells,while ASPP2 over-expression can suppress the OXA-induced autophagy. ASPP2 can promote apoptosis through p53-dependent and p53-independent pathways. The function of ASPP2 promoting cell apoptosis through p53-dependent and p53-independent pathways is not entirely achieved by inhibiting cell autophagy.

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