Identify GJB2 As Predictive Biomarker For Pancreatic Cancer And Mechanism

Objective: Pancreatic cancer is one of the most malignant tumor wordwide.The survival rate is of 5 years is less than 6%.In the word,it is the 8th cause of cancer-related death,and one of the most important diseases threatening human-being health and life.The incidence of pancreatic cancer is increasing year by year and showing a younger trend.The pancrese is poor in blood supply,so pancreatic cancer is resistive to chemotherapy and radioyherapy.Surgery is the most effective way to cure pancreatic cancer.Because of late onset,early metastasis,lots of patients have no chance to surgery.Pancreatic cancer is very malignant,so there are no effective biomarkers such as diagnosis and prognosis.The occurrence and development of pancreatic cancer is a long-term,multi-stage,multi-gene change cumulative process.Nowadays,the regulatory mechanisms have not been completely elucidated.With the rapid development of molecular biology and gene diagnosis technology,in addition to many genes related to panreatic cancer,some genes closely related to human pancreatic cancer have been found in recent years.The role of these genes in pancreatict cancer is attracting more and more attention.Methods: 1,Multiple bioinformatic analysis tools were utilized for identification and characterization of differentially expressed genes(DEGs)from a mergedmicroarray data(100 pancreatic cancer samples and 62 normal samples).Data from the GEO and TCGA database was utilized to validate the diagnostic and prognostic value of the top 5 upregulated/downregulated DEGs.Immunohistochemical assay(46paired pancreatic and para-cancerous samples)was utilized to validate the expression and prognostic value of COL11A1 and CTRL from these 10 genes.2,At the cellular level,pancreatic cancer cell lines As PC-1 and PANC-1were transfected by with GJB2-shRNA and the silencing efficiency was verified by Western-blot.After successfully silencing GJB2,the changes of AsPC-1 and PANC-1 cell proliferation were detected by CCK8;the changes of migration and invasion ability of AsPC-1 and PANC-1 cell were detected by Wound healing Assay and Transwell analysis;the changes of EMT marker of AsPC-1 and PANC-1 cell were detected by Western-blot and imunofluorescence.To further clarify the specific mechanism of GJB2 in regulating the invasion and metastasis of panreatic cancer,we used Western-blot to conform the relationship between MAPK singal transduction pathway.Results: 1,A total number of 300 DEGs were identified from the merged microarray data of 100 pancreatic cancer samples and 62 normal samples.These DEGs were closely correlated with the biological characteristics of pancreatic cancer.The top 5 upregulated/downregulated DEGs showed good individual diagnostic/prognostic value and better combined diagnostic/prognostic value.Validation of COL11A1,GJB2 and CTRL with immunohistochemical assay showedconsistent expression level with bioinformatics analysis and promising prognostic value.2,The functional experiments suggested that knockdown of GJB2 suppressed proliferation 、 migration、 invation and EMT transitoin of AsPC-1 and PANC-1 cel.Conclusion: 1,COL11A1,GJB2 and CTRL novel predictive biomarkers for pancreatic cancer.2,GJB2 is a promotor of invasion and migration in pancreatic cancer.GJB2 may be one protein of MAPK.