Aerobic exercise suppresses hepatocellular carcinoma by downregulating dynamin-related protein 1 through PI3K/AKT pathway

Objective: Exercise, as a common non-drug intervention, is one of several lifestyle choices known to reduce the risk of cancer. Mitochondrial division has been reported to play a key role in the occurrence and transformation of hepatocellular carcinoma(HCC). This study investigated whether exercise could regulate the occurrence and development of HCC through mitosis.Methods: Bioinformatics technology was used to analyze the expression level of dynamin-related protein1(DRP1), a key protein of mitochondrial division. The effects of DRP1 and DRP1 inhibitor(mdivi-1) on the proliferation and migration of liver cancer cells BEL-7402 were observed using cell counting kit-8, plate colony formation, transwell cell migration, and scratch experiments. Enzyme-linked immunosorbent assay, Western blot and real-time polymerase chain reaction were used to detect the expression of DRP1 and its downstream phosphoinositide 3-kinase(PI3 K)/protein kinase B(AKT) pathway. A treadmill exercise intervention was tested in a nude mouse human liver cancer subcutaneous tumor model expressing different levels of DRP1. The size and weight of subcutaneous tumors in mice were detected before and after exercise.Results: The expression of DRP1 in liver cancer tissues was significantly upregulated compared with normal liver tissues(P<0.001). The proliferation rate and the migration of BEL-7402 cells in the DRP1 overexpression group were higher than that in the control group. The mdivi-1 group showed an inhibitory effect on the proliferation and migration of BEL-7402 cells at 50 lmol/L. Aerobic exercise was able to inhibit the expression of DRP1 and decrease the size and weight of subcutaneous tumors. Moreover,the expression of phosphorylated PI3 K(p-PI3 K) and phosphorylated AKT(p-AKT) decreased in the exercise group. However, exercise could not change p-PI3 K and p-AKT levels after knocking down DRP1 or using mdivi-1 on subcutaneous tumor.Conclusion: Aerobic exercise can suppress the development of tumors partially by regulating DRP1 through PI3 K/AKT pathway.