AIM:To determine the expression of toll-like receptor 9(TLR9) in pancreatic tumor and the effects of cytosine phosphate-guanosine oligodeoxynucleotides 2216(CPG ODN2216) on biological behavior of pancreatic carcinoma cell line PANC-1 and explore their clinical significance.METHODS:The immunohistochemistry and Western blot were used to determine the expression of TLR9 protein in pancreatic cancer tissues,and immunofluorescence staining was performed to detect the TLR9 protein expression in pancreatic carcinoma cell line PANC-1.To assess the effects of CPG ODN2216 on the invasive property of Panc-1 cells,in vitro cell adhesion,wound-healing scrape,and invasion and cell colony formation were evaluated.RESULTS:TLR9 was highly expressed in pancreaticcancer tissues and PANC-1 cells.The percentage of positive cells expressing TLR9 protein in human pancreatic tissues,paracancerous tissues and normal tissues were 73.3%,33.3% and 20.0%,respectively,and the protein expression level of TLR9 was gradually descending(P < 0.05).In vitro tests in wound-healing scrape,cell adhesion,colony formation and matrigel invasion showed that the adhesion and motility of PANC-1 cells in CPG ODN 2216 treatment group were signif icantly lower than in the control group(P < 0.05).The cell growth assay showed that the proliferative ability of PANC-1 cells in treatment group was significantly decreased and CPG ODN2216 had an inhibitive effect in the growth of Panc-1 cells in a dose and time-dependent manner(P < 0.05).CONCLUSION:The gene of TLR9 is correlated with the invasive and metastatic potential of human pancreatic carcinoma,and CPG ODN2216 induces the inhibition of migration and invasion of Panc-1 cells. AIM: To determine the expression of toll-like receptor 9 (TLR9) in pancreatic tumor and the effects of cytosine phosphate-guanosine oligodeoxynucleotides 2216 (CPG ODN2216) on biological behavior of pancreatic carcinoma cell line PANC-1 and explore their clinical significance. METHODS : The immunohistochemistry and Western blot were used to determine the expression of TLR9 protein in pancreatic cancer tissues, and immunofluorescence staining was performed to detect the TLR9 protein expression in pancreatic carcinoma cell line PANC-1. Assess the effects of CPG ODN2216 on the invasive property of Panc-1 cells, in vitro cell adhesion, wound-healing scrape, and invasion and cell colony formation were evaluated.RESULTS: TLR9 was highly expressed in pancreatic cancer tissues and PANC-1 cells. percentage of positive cells expressing TLR9 protein in human pancreatic tissues, paracancerous tissues and normal tissues were 73.3%, 33.3% and 20.0% respectively, and the protein expression level of TLR9 was gr Adverse descending (P <0.05). In vitro tests in wound-healing scrape, cell adhesion, colony formation and matrigel invasion showed that the adhesion and motility of PANC-1 cells in CPG ODN 2216 treatment group were signif icantly lower than in the control group (P <0.05). The cell growth assay showed that the proliferative ability of PANC-1 cells in treatment group was significantly decreased and CPG ODN2216 had an inhibitive effect in the growth of Panc-1 cells in a dose and time-dependent manner (P <0.05). CONCLUSION: The gene of TLR9 is correlated with the invasive and metastatic potential of human pancreatic carcinoma, and CPG ODN2216 induces the inhibition of migration and invasion of Panc-1 cells.