Effects Of BMP-2 On Invasion Of Pancreatic Cancer And Its Mechanism

Objective:To investigate the levels of BMP-2 in pancreatic cancer tissues and serum and its relation to clinicopathologic parameters.Methods:BMP-2 protein expression in 10 pancreatic cancer,6 chronic pancreatitis and 6 normal pancreas samples was determined by Western blot analysis. Expression of BMP-2 in 42 pancreatic cancer,13 chronic pancreatitis and 6 normal pancreas tissues was examined by immunohistochemistry. The serum BMP-2 levels of 53 pancreatic cancers,7 patients with chronic pancreatitis and 20 normal controls were quantified by use of a commercially available ELISA kit.Results:There was a significant increase in BMP-2 protein levels in the pancreatic cancer samples compared with the normal pancreas samples (P<0.05). In contrast, BMP-2 protein levels were similar in chronic pancreatitis and normal pancreatic samples. By immunohistochemistry, BMP-2 was expressed in the cancer cells within the tumor mass. Positive rate of theⅢstage patients was higher than theⅠ+Ⅱstage patients (P＜0.05). Compared with the normal persons, pancreatic cancers showed a significant increase of the mean serum BMP-2 levels (P＜0.05). No significant difference in the mean serum BMP-2 levels was observed between the control subjects and the chronic pancreatitis patients (P>0.05). The metastatic disease group patients had a significantly higher level of serum BMP-2 than the group without metastatic group (P＜0.05).Conclusion:BMP-2 seems to have a role in progression to metastatic disease in pancreatic cancer, especially in the late stage of tumorigenesis, including invasion and metastasis. BMP-2 might be used to evaluate the prognosis of pancreatic cancers.Objective:To investigate the effect of BMP-2 on the invasion and EMT of Panc-1 cells.Methods:Panc-1 cells were cultured and treated with 0,1,10,100, 200 ng/ml BMP-2 medium for 24 hours, respectively, then invasive ability of cells was determined by transwell invasion assay, expression of E-Cadherin and Slug was detected by RT-PCR and Western blot. Treated with 0,1,10,100,200 ng/ml BMP-2 medium for 72 hours, respectively, cell morphology was observed by phase contrast microscopy.Results:1. Compared with the control group, BMP-2 had a significant increase number of the invaded cells in 10,100,200 ng/ml BMP-2 group respectively (P＜0.05).2. Compared with the control group, the expression of E-Cadherin decreased and Slug increased in Pan-1 cells treated with BMP-2(10,100, 200 ng/ml), and the change was in a concentration-dependent manner (P＜0.05).3. Treated with BMP-2(100,200ng/ml) exhibited dramatic changes in cell morphology, from a cuboid, epithelial-like shape to a spindle, fibroblastic-like appearance.Conclusion:BMP-2 induces invasiveness and EMT of Panc-1 cells.Objective:To observe whether BMP-2 activates PI3K/Akt pathway, then to investigate the role of PI3K/Akt pathway in BMP-2 induced invasion and EMT of Panc-1 cells.Methods:1. Panc-1 cells were cultured and treated with 100 ng/ml BMP-2 for 1 hour, expression of p-Akt, Akt and pSmadl,5,8 protein were detected by Western blot.2. Pretreated with 20μM LY294002, Panc-1 cells were cultured with 100 ng/ml BMP-2 for 1 hour, expression of p-Akt was detected by Western blot.3. Pretreated with 20μM LY294002, Panc-1 cells were cultured with 100 ng/ml BMP-2 for 24 hours. The invasive ability was determined by transwell invasion assay. Expression of E-Cadherin and Slug was detected by RT-PCR and Western blot. Pretreated with 20μM LY294002, Panc-1 cells were cultured with 100 ng/ml BMP-2 for 72 hours. The cell morphology was observed by phase contrast microscopy.Results:1. Compared with control group, the protein expression of pSmad1,5,8 and p-Akt were higher in BMP-2 group(P<0.05), but there was no significant difference in that of total Akt protein(P>0.05).2. Compared with BMP-2 group, the protein expression of p-Akt was lower in BMP-2+LY294002 group(P<0.05).3. Compared with BMP-2 group,Panc-1 cells remained the epithelial-like shape, expression of E-Cadherin increased and slug decreased in BMP-2+LY294002 group(P<0.05);There was no significant difference between control group and BMP-2+LY294002 group(P＜0.05).4. The invaded cells number in BMP-2+LY294002 group is more than control group, and less than BMP-2 group(P<0.05).Conclusion:BMP-2 induces invasion and EMT of Panc-1 cells via PI3K/Akt pathway activation.