The Preliminary Study On Proliferation And Metastasis Of A New LncRNA-TRERNA1 In Hepatocelluar Carcinoma

Background: Long non-coding RNAs(lncRNAs)are a novel class of regulatory genes who are longer than 200 nucleotides but they don't have the protein coding potential.lncRNAs regulate the gene expression by chromatin remodelling,epigenetic regulation,enhancer function,transcription,splicing and RNA decay control.With the study of lncRNAs,we are finding their roles in the cancer progression,which showed us more information about the mechanism of tumorigenesis and progression and supplied the new targets for Targeted therapy.Objective: TreRNA is a new type of lncRNAs identified recently.In our research,we studied the roles of TRERNE1,which belonging to TreRNA,in the proliferation and metastasis of hepatocellular carcinoma.Merthods: Firstly,we detected the expression of TRERNA1 in primary cancer tissues and adjacent tissues of hepatocellular carcinoma and colorectal cancer using In Situ Hybridization(ISH)on tissue microarrays.We analysed the subcellular localization of TRERNA1 and the relationship between its expression and clinicopathological parameters(such as lifetime,the size of the tumor,clinical stages and lymph node metastasis).Results: The results showed that TRERNA1 were mainly located in cytoplasm,and its expression in primary cancer tissues is higher than in para-carcinoma tissues.Meanwhile,in the primary colorectal cancers,there is a negative correlation between TRERNA1 expression and pathological classification.In para-carcinoma tissues of hepatocellular carcinoma,there is a negative correlation between TRERNA1 expression and survival state(1 refers to death,2 refers to survival).The COX proportional hazards regression analysis showed that the TRERNA1 expression is one of the risk factors of lifetime.Secondly,we did the study on hepatoma carcinoma cells using the method of knocking down the TRERNA1 expression of Bel-7402 cell line and upregulating the TRERNA1 expression of HepG2 cell line.After the cell models were successfully constructed,we used the method of wound-healing assay to detect the changes of cell migration ability,the results showedthat after knocking down the TRERNA1,cell migration ability of Bel-7402 was weaker than the control,after upregulating the TRERNA1 expression of HepG2,its cell migration ability was stronger than the control.The ability of forming Vasculogenic Mimicry was detected by the Tube Formation Assay.After knocking down the TRERNA1 expression of Bel-7402,its ability of forming Vasculogenic Mimicry was weakened,and after upregulating the TRERNA1 expression,this ability of HepG2 was enhanced.Cell proliferation in vitro was assessed by cell counting kit-8(CCK8)assay.The results also showed that cell proliferation was suppressed because knocking downTRERNA1 and was enhancedbecause TRERNA1 upregulating.Cell apoptosis was evaluated using Flow cytometry.It showed that the rate of cell apoptosis was increased after knocking down the TRERNA1 expression of Bel-7402,and it was reduced after upregulating the TRERNA1 expression of HepG2.These results showed that TRERNA1 could enhance the cell migration,proliferation,forming Vasculogenic Mimicry ofhepatoma carcinoma cells and suppress their apoptosis.At last,we used the method of microarray to detect the differential expressed genes between the upregulating group and the negative control group,which could find the downstream regulationg moleculars of TRERNA1.We found349 differential expressed genes including some genes which play roles in Cell proliferation,apoptosis,and metastasis.Conclusion: TRERNA1 is benefit to the proliferation and matastasis of hepatoma carcinoma.