Roles And Mechanisms Of MiR-301a And CAV-1 In The EMT Of The Pancreatic Cancer And Gastric Cancer

Background & Objetive: Epithelial-mesenchymal transition(EMT)plays an important role in the invasion and metastasis of cancer in digestive cancers.This study aimed to investigate the molecular mechanisms of EMT in pancreatic cancer and gastric cancer,and to explore the role of mi R-301 a in hypoxia-induced pancreatic cancer EMT and its related molecular mechanisms.Moreover,we aimed to elucidate the correlation between CAV-1 expression and clinicopathological features,and explore the role of CAV-1 in gastric cancer cells EMT.The result of this experiment will probably provide new cancer biomarkers markers and treatment targets for the diagnosis and treatment of pancreatic cancer and gastric cancer.Part 1: The roles and mechanisms of mi R-301 a in hypoxia-induced pancreatic cancer EMTMethods: The expression of mi R-301 a in pancreatic cancer tissue microarray was detected by in situ hybridization.The correlation between mi R-301 a expression and clinicopathological features as well as prognosis was analyzed.The effects of hypoxia on the expression of mi R-301 a and the occurrence of EMT in pancreatic cancer cells were studied by Western Blot and immunofluorescence assay and other biological technology.The roles of mi R-301 a expression on pancreatic cancer cells EMT was studied after overexpression and knockout of mi R-301 a in pancreatic cancer cell lines.Si RNA interference technique and double luciferase reporter gene technique were used to study the regulation of mi R-301 a by HIF-1? and HIF-2?.The targeting effect of mi R-301 a on TP63 was verified by double luciferase reporter gene technique.Results: The expression of mi R-301 a was high in pancreatic cancer tissues compared with adjacent tissues,and the expression of mi R-301 a was correlated with pathological grade,AJCC stage and lymph node metastasis status(p <0.05).High expression of mi R-301 a predicred worse patient survival(p <0.05).The expression of mi R-301 a in the pancreatic cancer cells can be induced by hypoxia.Overexpression or knockout of mi R-301 a promoted or inhibited pancreatic cancer cells EMT and the accumulation of HIF-1?.HIF-2? knocking down by si RNA inhibited the expression of mi R-301 a in hypoxia.And HIF-2? promoted the transcriptional activity of mi R-301 a promoter.Mi R-301 a bound to the 3 'UTR region of its target gene TP63 and inhibited TP63 protein expression.Knockdown or overexpression of TP63 could regulate mi R-301 a induced pancreatic cancer cell EMT.Conclusion: HIF-2? upregulated the expression of mi R-301 a in hypoxic environment.Mi R-301 a inhibited the expression of target gene TP63 and promoted the accumulation of HIF-1? which induced pancreatic cancer cells EMT.Part ?: The expression of CAV-1 in gastric cancer and its relationship with gastric cancer EMTMethods:Immunohistochemistry assay was used to detecte the expression of CAV-1 and E-cadherin.The m RNA expression of CAV-1 and E-cadherin in gastric cancer tissues and gastric cancer cells was detected by Realtime PCR.The effects of CAV-1 on EMT and metastasis of gastric cancer cells were studied by si RNA interference of CAV-1.Results: CAV-1 and E-cadherin were highly expressed in normal gastric mucosa compared with gastric cancer tissues.The expression level of CAV-1 and E-cadherin were correlated with tumor grade,stage and metastasis(p <0.05).Further analysis showed that CAV-1 was positively correlated with E-cadherin expression.Downregulation of CAV-1 could reduce the expression of E-cadherin and promote gastric cancer cells EMT.Conclusion: The low expression of CAV-1 was an important factor in the occurrence of gastric cancer cells EMT.CAV-1 downregulation could induce the EMT of gastric cancer cells by regulating the expression of E-cadherin.