The Expression Of Midkine And Its Relationship With Cell Proliferation And Apoptosis In Pancreatic Cancer

Objective: To investigate the expression and significance of Midkine protein and its relationship with cell proliferation and apoptosis in human pancreatic cancer, and study its possible mechanism of action.Method: The immunohistochemical staining (SP) method was used to detect the expression of Midkine protein, proliferating cell nuclear antigen Ki67 and Caspase-3 in 49 cases of pancreatic cancer tissues, 13 cases of chronic pancreatitis tissues and 15 cases of normal pancreatic tissues. The TUNEL method was used to detect apoptotic index in pancreatic cancer tissues and normal tissues.Results: Midkine protein was not detected in normal pancreatic tissues and chronic pancreatitis tissues. The positive rate of Midkine protein is 71.4% (35/49) in pancreatic cancer, and the expression was significantly correlated with tumor's histological grades, clinical stages and lymph node metastasis (P<0.05). Ki67 protein was not detect in normal pancreatic tissues, the positive rate is 23.1% (3/13) in chronic pancreatitis tissues and 81.6% (40/49) in pancreatic cancer. The expression rate of Ki67 was significantly correlated with tumor's histological grades, clinical stages and lymph node metastasis (P<0.05). The positive rate of caspase-3 were 46.7% (7/15), 53.8% (7/13) and 77.6% (38/49), respectively, in normal pancreatic tissues, chronic pancreatitis tissues and pancreatic cancer, the expression was only correlated with tumor's histological grades (P<0.05). The expression level of Midkine protein has a positive relationship with Ki67 in pancreatic cancer (r=0.4, P<0.05), has a negative correlation with caspase-3 (r=-0.34, P<0.05). The mean apoptotic index is 5.13±2.69 in patients with Midkine gene positive expression, which was significantly lower than that in patients negative expression of Midkine (7.93±6.65), (P<0.05).Results: The gene of Midkine participate the occurrence and development of pancreatic cancer, the intensity of express was follow the advancement of tumor. The expression of Midkine maybe can induce the cell proliferation and inhibit the apoptosis of tumor cells, maybe these are the important mechanism of Midkine to participate in pancreatic cancer occurrence and development. Midkine gene inhibits the apoptosis of tumor cells possibly through suppression the activity of caspase-3 protein. Determination of Midkine protein may be as a useful marker in the diagnosis, differential diagnosis and judgment the prognosis of pancreatic cancer.