Biofunction And Mechanism Of DDX5 RNA Helicases In The Occurrence And Progression Of Hepatocellular Carcinoma

Objective To investigate and analyze the expression level of DDX5 in HCC specimens as well as its correlation with clinical characteristics,also to decipher the its underlying mechanism in modulating HCC tumorigenesis and progression.These studies aim at seeking for more sensitive and special biomarkers expected to facilitate the diagnosis and treatment of HCC.Method The m RNA level of DDX5 in HCC patients and normal tissues was evaluated by TCGA database proved by quantitative Real time PCR,while the protein level of DDX5 in HCC specimens and adjacent tissues was then testified by IHC.Then,the correlation of DDX5 with clinical characteristics was analyzed according to IHC results,which also manifested its association with prognosis of HCC patients.In addition,a series of vitro studies were performed in order to discover the effect of DDX5 on HCC proliferation and metastasis by knockdown DDX5.Besides,western blotting was used to investigate whether DDX5 participated in EMT process.Moreover,KEGG database was analyzed to obtain potent signaling pathways regulated by DDX5,verified by western blotting.Result1.DDX5 was overexpressed at both transcriptional and translational levels in HCC tumor tissues compared to normal tissues.2.DDX5 was overexpressed in HCC and also correlated with tumor size(p<0.001),N stage (p<0.013),M stage(p=0.006),tumor differentiation(p<0.001),AJCC stage(p=0.001).However,there was no association between DDX5 and age,gender and liver cirrhosis in HCC.3.Survival analysis by using Kaplan-Meier suggested that DDX5 strongly is related with Disease-Free Survival(DFS,p=0.016)and Over Survival(OS,p=0.032).4.Inhibition of DDX5 led to blunt migratory and invasive abilities of HCC cell lines and Western blot analysis suggested that DDX5 could promote EMT process.5.CCK8 and colon formation assays revealed that DDX5 knockdown resulted in inhibitory cell proliferation remarkedly.6.KEGG analysis showed that PI3K/AKt signaling pathway obtained the highest enrichment score as well as low p-value,and the protein levels of Akt and p-AKt were changed due to DDX5 knockdown,suggested by Western Blotting.Conclusion DDX5 was overexpressed in HCC at both m RNA and protein levels,which was a prognostic factor of HCC.DDX5 could promote HCC proliferation by modulating Akt signaling pathway in vitro,while DDX5 also accelerated EMT process leading to enhancing the ability of metastasis in HCC cell lines.Collectively,these results suggested that DDX5 was closely related to HCC tumorigenesis,which might be an important biomarker for HCC.