Objective To evaluate the effect and mechanism of DNA methyltransferase-3 a(DNMT3 a) on the chemosensitivity of pancreatic cancer cells to gemcitabine(GEM). Methods MTT assay was used to determine the effect of GEM and DNMT3 a on the proliferation of pancreatic cancer cell line,Panc-1. Cells were transfected with siRNA to downregulate the expression of DNMT3 a. The expression of DNMT3 a,CDA,p-STAT3 s,and STAT3 in PANC-1 cells transfected with siDNMT3 a were detected by Western blotting. Flow cytometry was u...