Objective To investigate the role and mechanism of β-catenin protein in the maintenance of malignant biological characteristics of pancreatic cancer stem cells.Methods Primary pancreatic cancer cells were isolated and cultured,then divided into the negative control(NC)group and the AD β-catenin group,cells in the NC group were transfected with negative empty vectors,and cells in the AD β-catenin group were transfected with β-catenin overexpression lentiviral vectors.Flow cytometry was used to analyze the expression of tumor stem cell surface markers CD24,CD44,and ESA.CD24+CD44+ESA+cells were sorted and expanded in culture,and their sphere-forming ability,colony-forming ability,proliferation ability,invasion ability and migration ability,cell cycle,and apoptosis were assessed.The impact of β-catenin overexpression on the biological characteristics of pancreatic cancer stem cells was analyzed.Results The relative expression levels of β-catenin mRNA and protein in the AD β-catenin group were significantly higher than those in the NC group(P=0.016,P=0.015).Flow cytometry analysis revealed that the percentage of CD24+and CD24+CD44+ESA+cells in the AD β-catenin group was significantly higher than that in the NC group(P<0.05).Compared with the NC group,the colony-forming ability,sphere-forming ability,numbers of invasion and migration of pancreatic cancer stem cells in the AD β-catenin group were significantly increased(P<0.05).The optical density(OD)values at 24 hours,48 hours,and 72 hours were significantly higher in the AD β-catenin group than those in the NC group(P<0.05).Compared with the NC group,the proportion of G0/G1 phase cells in the AD β-catenin group was significantly decreased(P<0.05),and the proportion of S phase cells was increased(P<0.05).The apoptosis rate in the AD β-catenin group was significantly lower than that in the NC group(P<0.05).Conclusion β-catenin can improve the percentage of CD24+CD44+ESA+cells in primary pancreatic cancer cells,promote sphere-forming ability,enhance cell proliferation,invasion,and migration,and inhibit cell apoptosis,thereby maintaining the malignant biological characteristics of pancreatic cancer stem cells.