The Expression And Relationship Of PTEN And Mutant Type P53 Gene In Tissue Of Gastric Cancer

Objective:To study the expression of cancer-suppressing genes, PTEN and mutant type p53, in gastric cancer and their relationship with the occurrence and clinicopathological features of the disease.Methods:The expression of PTEN and mutant type p53 protein was detected by immunohistochemistry method in 62 specimens of gastric cancer, corresponging adjacent mucosa of gastric cancer and normal gastric mucosa. After routinely dewaxing and hydration, antigen in specimens proceeded to be repaired according to statement by steps on the immunohistochemistry of kits for testing. The positive biopsy and PBS replaced the first antibody to set up positive and negative control.Results:The positive rates of expression of PTEN and mutant type p53 protein in gastric cancer were 48.39% and 45.16%, respectively. Those in corresponding adjacent mucosa of gastric cancer were 90.32% and 14.51%, respectively. The positive rate of mutant type p53 protein in normal gastric mucosa was 9.68%, and PTEN protein expressed in all specimens of normal gastric mucosa. The difference of PTEN and mutant type p53 protein expression was significant between cancer and normal gastric mucosa(P<0.05). The expression of PTEN protein was significantly associated with clinical staging, differentiation level, lymph node metastasis, and distant metastasis; but not with sex, age,tumor location, tumor size and invasion level(P>0.05). The expression of PTEN protein inversely correlated with the expression of mutant type p53 protein.Conclusion:(1) The abnormal expression of PTEN protein is related to oncogenesis and progression of gastric cancer.(2) The expression of PTEN protein is associated with multiple clinicopathological characteristics relevant to prognosis. The expression of PTEN gene was significantly associated with clinical staging, differentiation level, lymph node metastasis, and distant metastasis. It is suggested that the expression phenotype of PTEN gene could be an assistant parameter for the evaluation of some biological behavior of gastric cancer.(3) The abnormal expression of p53 protein is related to oncogenesis and progression of gastric cancer.(4) The expression of PTEN protein inversely correlated with the expression of mutant type p53 protein.