Study On The Function And The Molecular Mechanism Of DNM3 Inhibiting The Development Of Hepatocellular Carcinoma

Objection:Hepatocellular carcinoma is one of the most common cancers in China,however,tumor recurrence and metastasis is the main reason for treatment failure.Dynamin 3(DNM3)is a newly discovered tumor suppressor gene,and it is methylated in tumor tissues compared to adjacent normal tissues inhepatocellular carcinoma patients with a genome-wide DNA methylation profile.Downregulation of DNM3 is correlated with worse prognosis for hepatocellular carcinoma patients.The mechanism of DNM3 in hepatocellular carcinoma don’t elucidate,this study intends to clarify DNM3 mRNA expression in tumor tissues and its adjacent normal tissues of hepatocellular carcinoma and its clinical significance.Explore the biological function and mechanisms of DNM3 in hepatocellular carcinoma growth and metastasis.Methods:(1)DNM3 mRNA a expression in tumor tissues and its adjecent non-tumor tissuesof 68 patients with hepatocellular carcinoma was detected by q RT-PCR.Further more analyzed the relationships between DNM3 expression and clinical parameters of hepatocellular carcinoma tissues with SPSS 13.0.(2)The p IRES2-EGFP/DNM3 vector was transfected into hepatocellular carcinoma cell lines Hep G2 and Hep3 B to up-regulate DNM3,the biological effects were investigated in hepatocellular carcinoma cells.(3)The change of NOS and NO were detected by NO correlation detection kit,associated proteins in hepatocellular carcinoma were detected by western blot after DNM3 was upregulated.Results:(1)The mRNA relative expression and protein expression of DNM3 in hepatocellular carcinoma tissues were significantly lower than its adjacent non-tumor tissues(P<0.0001),and in 76.5%(52/68)samples DNM3 expressed lower in tumor tissues than that in the matched adjacent non-tumor tissues(P<0.0001).Low expression of DNM3 in hepatocellular carcinomawas associated with tumor metastasis(P= 0.001)and vein invasion(P=0.047),but no significant correlation was found with other features.(2)Overexpression of DNM3 in hepatocellular carcinoma cells inhibited in vitro cell growth,promoted cell apoptosis,and decreased migration and invasion and in vivo tumorigenicity,and arrested cell cycle progression at G0/G1 phase.(3)NO content and proliferation-associated protein P53,P21 expression was increased in the hepatocellular carcinoma cells after DNM3 was up-regulated.While,MMP-9 expression was decreased and EMT-associated protein expression was changed in the hepatocellular carcinoma cells.Conclusion:DNM3 expression was significantly droped in hepatocellular carcinoma tissues and its expression level was correlated withtumor metastasis and vein invasion.Overexpression of DNM3 in hepatocellular carcinoma cells inhibited the malignant behavior of cancer cells.DNM3 exerted its effects on development process of hepatocellular carcinoma cells by regulating NOS/NO/P53/P21 signaling pathway and MMP-9.