The Expression Of P73 Protein In Pancreatic Neoplasms And Its Clinical Significance

Pancreatic carcinoma is one of the most malignant neoplasms in the digestive tumors .Its prognosis is very poor .Up to now radical resection seems the best choice for the patients, but the results of studies suggested that the survival rate of pancreatic carcinoma after resection procedure is still less than 5%.So the research of pancreatic carcinoma is the focus on enhancing the basic and clinical research, rising the level of the dignosis and therapy ,and improving the prognosis of the pancreatic carcinoma.At present we know that oncogene and tumor-suppressor genes work together to lead to the development and occurrence of the tumor .The inactivation of anti-oncogen happeneds frequently in the entity neoplasm .The p53 gene have extensive mutations in the human neoplasm and the investigation of this gene is very profound .Recently ,two kinds of proteins named as p63 and p73 are found out ,which have much homology with p53. Both of them can activate the p53-related target genes and cause the retention of cell cycle and apoptosis of the cell .The scientists concentrate their work to the functions of p63 and p73 in molecular biology interaction and the differentiation and relation in p53 family genes.The status and role of p53 family genes in the tumor is also very noticeable.Objective : To study the expression of p73 gene in pancreatic neoplasms ,and the relationship between the expression of p53 family,and to explore its clinical significance in pancreatic neoplasms.Methods: The expression of p73 p63 and p53 are detected by immunohistochemistry methods in 63 patients with pancreatic neoplasm,including of 42 cases of ductal adenocarcinoma,6 cases of adenosquamous carcinoma,8 cases of malignant changes in cystadenoma and 7 cases of cystadenoma,compared with 6 cases of chronic pancreatitis.Results : 1.p73 gene overexpression was observed in 21 of the 42 pancreatic ductal carcinoma case examined. Among them, the expression of the well- differentiated, moderately-differentiated and poorly-differentiated carcinoma was 76.9% (10/13), 46.2%(6/13)and18.2%(2/11) respectively. The incidence of the p73 overexpression in poorly-differentiated ductal carcinoma was significantly lower(p<0.05).Six of the eight cystic adenocarcinoma overexpressed p73 protein while only one case overexpressed this protein of the seven cystic adenoma.2.p73 gene expression of the pancreatic malignant neoplasms was 55.4%(31/56) while the malignant neoplasms's was 15.4%(2/11).There is significant difference between them(p<0.05).However it was no related to the surgicall stage.3.We compared p73 overexpression with various clinicopathological features,and found that it was more frequently observed in cases with low biological aggressiveness such as those without lymph node metastasis,of small size and of well prognosis(p<0.05).4.In pancreatic ductal adenocarcinoma,the overexpression of the p73 and p53 was 52.1%(25/48) and 56.2%(27/48) respectively, but there is no relation between them.Conclusions:1.p73 gene was high expression in pancreatic carcinoma, and was negative relation to differentiation of the ductal carcinoma. It indicates that the gene mutation of the p73 may play a important role in the occurrence and development of pancreatic carcinoma. 2.The p73 overexpression is significant difference between pancreatic malignant disease and non-malignant one, and is inversely correlated with biological aggressiveness.3. The p73 gene is involved in the processs of the malignant change of the cystadenoma. The staining of p73 is useful to diagnosis pancreatic cystic adenocarcinoma.4.Although p53 p63 and p73 all can express in the pancreatic neoplasm, there is no relation among them. p63 is overexpress in adenosquamous while p73 gene play an important roles in cystic adenocarcinoma. It indicates that they have their unique action in occurrence and development of pancreatic carcinoma respectively.