内质网应激通过ATG5介导的自噬通路促进结直肠癌细胞增殖和侵袭

Endoplasmic reticulum stressed promotes colorectal cancer cell proliferation and invasion through ATG5-mediated autophagy pathway

目的探讨内质网应激通过ATG5介导的自噬通路调控结直肠癌细胞增殖及其潜在机制。方法通过生物信息学方法分析PERK、ATF6和ATG5在结直肠癌组织和癌旁组织中的表达及PERK和ATG5表达的相关性。使用qRT-PCR法检测PERK在结直肠癌细胞中的表达水平,CCK-8法检测细胞增殖,Transwell法检测细胞侵袭能力,Western blot法检测蛋白表达水平,透射电镜检测细胞自噬。结果PERK和ATF6在结直肠癌组织高表达,且PERK在结直肠癌细胞中高表达,结直肠癌细胞株HCT116、SW480、HT29、LoVo和正常结肠FHC细胞株中PERK的表达水平分别为(1.51±0.04)、(3.12±0.05)、(2.19±0.04)、(2.38±0.06)和(0.98±0.04)(P<0.001)。过表达PERK促进结直肠癌细胞增殖和侵袭。PERK和ATG5表达呈正相关(r=0.52,P<0.001),过表达PERK促进ATG5蛋白表达(1.00±0.04)、(3.53±0.07)(t=74.62,P<0.001)。ATG5在结直肠癌组织中高表达,过表达ATG5可促进结直肠癌细胞增殖,侵袭和细胞自噬[空白对照组、阴性对照组、ATG5过表达组中自噬小体数量分别为(4.33±1.53)、(4.00±1.00)、(9.67±2.52)(t=3.14、3.62,P=0.035、0.022)],且ATG5通过自噬通路促进结直肠癌细胞增殖和侵袭。结论内质网应激的结直肠癌细胞可通过ATG5介导的自噬通路促进结直肠癌细胞增殖和侵袭。

Objective To explore the effect of endoplasmic reticulum stressed(ER)on colorectal cancer(CRC)cell proliferation and invasion via ATG5-mediated autophagy pathway and the underlying mechanism.Methods We performed bioinformatics analysis to identify the expression level of PERK,ATF6 and ATG5 in CRC tissues and adjacent tissues and the correlation between PERK and ATG5 expression in CRC tissues.The expression level of PERK in CRC cell lines was examined by qRT-PCR assay.Cell proliferation was quantified by CCK-8.The invasion of the cells was detected by Transwell.Western blot assay was performed to verify the levels of protein.The levels of autophagy were examined by electron microscopy.Results PERK and ATF6 expression in CRC tissues was higher than that in the adjacent tissues and PERK expression was higher in CRC cells than intestinal mucosal cells.Expression level of PERK in CRC cell lines HCT116,SW480,HT29,LoVo and colonic mucosa cell lines FHC was 1.51±0.04,3.12±0.05,2.19±0.04,2.38±0.06 and 0.98±0.04(P<0.001).The increased expression of PERK promoted CRC cell proliferation and invasion.PERK expression levels was positively associated with ATG5 expression levels(r=0.52,P<0.001)and overexpression of PERK accelerated the protein expression of ATG5(1.00±0.04,3.53±0.07,t=74.61,P<0.001).ATG5 was highly expressed in CRC tissues.Overexpression of ATG5 could promote proliferation,invasion and accelerate autophagy of CRC cells(the number of autophagosomes in the blank control group,the negative control group and ATG5-Overexpression group was 4.33±1.53,4.00±1.00,9.67±2.52,and t=3.14,3.62,P=0.035,0.022,respectively).ATG5 promoted colorectal cancer cell proliferation and invasion through autophagy pathway.Conclusion ER stressed-CRC cells could promote CRC cell proliferation and invasion through ATG5-mediated autophagy pathway.