The role of ASPP2 in starvation-induced autophagy and apoptosis of HCT116 cell line
10.3760/cma.j.issn.1007-631X.2013.02.015
- VernacularTitle:p53凋亡刺激蛋白2对饥饿诱导的大肠癌HCT116 p53-/-细胞自噬和凋亡的影响
- Author:
Qingsheng HOU
;
Wei DING
;
Dexi CHEN
;
Yulin ZHANG
;
Hongliang GUO
- Publication Type:Journal Article
- Keywords:
Colorectal neoplasms;
Tumor suppressor protein,p53;
Autophagy;
Apoptosis
- From:
Chinese Journal of General Surgery
2013;(2):129-133
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the role of ASPP2 (apoptosis stimulating protein 2 of p53,ASPP2) in starvation-induced autophagy and apoptosis of colorectal cancer HCT116 p53-/-(p53 gene deletion) cell line.Methods The study included three experiment groups:green fluorescent protein adenovirus (rAd-GFP) infection group,autophagy inhibitor LY294002 treatment group and ASPP2 adenovirus (rAd-ASPP2) infection group.Celluar autophagy and apoptosis were induced by coculturing with serum-free medium for 0 h,24 h,48 h.Apoptosis level was detected by Calcein/PI uptaking test.Autophagy level was observed under the fluorescence microscope via transfection with cerise fluorescent protein autophagy plasmid CFP-Lc3.Results In control group,starvation for 24 hours significantly promoted autophagy of HCT116 cells (0 h:1.04 ±0.24; 24 h:12.17 ±0.86,P <0.05),while apoptosis was not increased (0 h:2.01% ±0.06%; 24 h:3.23% ±0.34%,P >0.05).With 48 h starvation,autophagy(0 h:1.04 ±0.24; 48 h:21.09 ±3.32) and apoptosis(0 h:2.01% ±0.06% ; 48 h:30.20% ±3.18%)of HCT116 increased (P < 0.05).With the use of LY294002 apoptosis induced by 24 h starvation significantly increased (rAd-GFP group:3.23% ± 0.34% ; LY294002 group:15.68% ± 1.24%,P <0.01),but aopotosis under 48 h starvation decreased (rAd-GFP group:30.20% ± 3.18%; LY294002group:25.44% ± 3.01%,P < 0.05).With ASPP2 transfection,autophagy under 24 h starvation significantly declined (rAd-GFP group:12.17 ± 0.86,ASPP2 group:1.45 ± 0.45,P < 0.01),and apoptosis increased(rAd-GFP group:3.23% ± 0.34% ; ASPP2 group:10.45% ± 0.81%,P < 0.05).Both autophagy (rAd-GFP group:21.09 ± 3.32; ASPP2 group:29.93 ± 3.48) and apoptosis (rAd-GFP group:30.20% ±3.18% ; ASPP2 group:36.72% ±2.74%) were higher than that in controls under 48 h starvation (P < 0.05).Conclusions ASPP2 probably promotes apoptosis of colorectal cancer cells by two-way regulated autophagy.