The Mechanism Of LncRNA-H19in Developmentand Metastasis Of Gastric Cancer

Background: Gastric cancer is one of the most common cancers in China which has ahigh incidence and poor prognosis. Long non-coding RNAs (lncRNAs) play key rolesin the development and progression in some carcinomas which has been reported inrecent years. We found that the expression of lncRNA-H19(H19) was much higher ingastric cancer tissues than that in paired normal tissues.As we known, miR-675isderived from the first exon of H19. In this project, we try to find the role of H19andmiR-675in gastric cancer and uncover the interaction of H19with its downstreamtarget genes in the coexpression network of H19. Methods: We detected theexpression of H19and miR-675in74gastric cancer tissues together with pairednormal tissues and analysis the correlationship between H19and miR-675expressionand the survival time of the patients. We built up H19and miR-675overexpressioncell models on SGC7901and H19and miR-675knock-down cell models on MKN45.Then, we setup CCK8proliferation assay, Transwell migration and invasionassay,wound-healing assay together with nude mice subcutaneous transplantationtumor models and peritoneal disseminated models to study the role of H19andmiR-675in proliferation and invasion of gastric cancer in vitro and in vivo. We alsobuilt the co-expression Network of H19to locate and find out the genes that interact with H19. Results: The Overall Survival (OS) in the patients with low H19expressionis much longer than that with high H19expression. What’s more, theANOVAregression analysis shows that the expression of H19was one of the prognostic factorsin gastric cancer. We found the overexpression of H19or miR-675can enhance cellproliferation, migration, invasion and metastasis in vitro and in vivo. While, whenKnock-down H19or miR-675cell proliferation, migration, invasion and metastasiswas suppressed t. We demonstrate that ISM1was the target gene of H19by RIPAssayand CALN1was the target gene of miR-675by DLRAssay. Furthermore, fromwestern blot assay, we found that the protein expression of ISM1was positivecorrelation with H19but the protein expression of CALN1was negative correlationwith miR-675. Conclusion: H19was important for gastric cancer growth andmetastasis. It can upregulate the expression of ISM1and H19derived miR-675candownregulate the expression of CALN1. Both H19and miR-675may serve as apotential target for targeting therapy in the future.