Objective Exosomes play an important role in the occurrence and development of hepatocellular carcinoma.This study aims to investigate the effects of exosomes on the proliferation,apoptosis,autophagy,and exosome release of HepG2 hepatocellular carcinoma cells and the related mechanisms.Methods Exosomes of HepG2 cells were extracted by ultrafast centrifugation.Exosome morphology,diameter distribution and marker protein expression of HepG2 cells were analyzed by transmission electron microscopy,nanoparticle tracking and Western blotting analysis.After the co-culture of exosomes and HepG2 cells,a CCK-8 kit was used to detect the proliferation of HepG2 cells,the apoptosis of HepG2 cells was detected by flow cytometry,and the expressions of apoptosis-related proteins(Bax,Bcl-2)and autophagy-related proteins(LC3-Ⅱ/LC3-Ⅰ,p62,Beclin-1)were detected by Western blotting.Results The morphology of exosomes extracted from HepG2 cells was consistent with the characteristics of exosomes,and the diameter between 30 and 150 nm.The marker proteins Alix and CD63 were significantly expressed.The results of CCK-8 showed that the absorbance of HepG2 cells in the 24 h exosome group was not significantly different from that in the control group(P＞0.05),but the absorbance of the exosome group at 48 hours and 72 hours were higher than that of the control group(P＜0.05).Flow cy-tometry showed that the apoptosis rate was(14.96±0.28)％in the control group and(11.16±0.50)％in the exosome group,and the apoptosis rate decreased(t=11.485,P＜0.001).Western blotting results showed that compared with the control group,the expression of apoptosis-related protein Bcl-2 in exosome group was up-regulated(P＜0.01),and the expression of Bax was down-regulated(P＜0.01).Autophagy associated protein LC3-Ⅱ/LC3-Ⅰ expression was up-regu-lated(P＜0.01),Beclin-1 expression was up-regulated(P＜0.05),and p62 expression was down-regulated(P＜0.01).Conclusion Exosomes derived from HepG2 cells can promote cell proliferation and inhibit apoptosis by inducing up-reg-ulation of autophagy.
维普
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