Relation Of PTEN,nm23,bcl-2 And P53 Protein Expression To The Biological Characteristics Of Gastric Cancer

Objective: To study the relationship among the expression of PTEN, nm23, bcl-2 and p53 and clinicopathology in the patients with gastric cancer. Method 85 cases of different differentiated gastric cancer, 11 cases of well-differentiated gastric cancer, 29 cases of mid-differentiated gastric cancer and 45 cases of poor-differentiated gastric cancer, were stained by immunohistochemical LSAB method.45 cases were studied by PCR-SSCP to detect the mutational differentiation genic mutation in p53 (exon7) and PTEN (exon5, exon8) . 3 cases with PTEN mutation were further studied with DNA sequence assay. Results The positive rates of p53 protein expression was 41.18% , there were significant deviation between early gastric cancer (15.38%) and progressive gastric cancer (45.83%) (X2=4.097 P<0.05), the difference exsit significantly between patients with lymphatic metastasis and non-lymphatic metastasis (x2=11.036, p<0.001) ; The positive density of p53 was higher in patients with lymphatic metastasis and in patients of progressive gastric cancer significantly than those of patients with non-lymphotic metastasis (u=3.055 p<0.01) and early gastric cancer (u=1.972 p<0.005);P53 mutation was more frequently in poor-differentiated gastric cancer than patients with well- differentiated gastric cancer (p=0.0085) and with lymphatic metastasis(p=0.043),and had no relationwith the deepth of infiltration. The positive rates of bcl-2 protein expression was 52.94% ,that of patients with progressive gastric cancer was significanty higher than that with early gastric cancer(x2=6.1803 p<0.05),and had no relation with lymphatic metastasis (x2=0.4561 p>0.05), differentiated degree(x2=0.386 p>0.05) and cellular types(x2= 1.5921 p>0.05).The positive rate of nm23 protein expression was 56.47%,and it was significantly higher in progressive gastric cancer and patients with non lymphatic metastasis than that in early gastric cancer(x2=7.6737 p<0.01) and those with lymphatic metastasis(x2=7.6937 p<0.01).The mutatual rate of PTEN was 7.14%(3/42),there were no significant difference in groups of different clinical stages(x2=0.1216 p=7273) and different differentiated degree(x2=0.7602 p=0.3833). PTEN mutation DNA sequence assay found A basic deletion at 25point in exon5,G mutae to C C mutate to A at 937 and 992 in exon8 differently .Patients with p53(+) and nm23(-) were significantly apt to occur lymphatic metastasis than those with p53(-) and nm23(+)(x2=5.036 p<0.05),no difference were found in other groups (p>0.05).Conclusion:1.p53 nm23 bcl-2 protein expression had synergistic effect to the gastric metastasis;2.the p53 genic mutation assay may be helpful to identify the patients with high malignant gastric cancer;3.PTEN mutations were apt occur in poor-differentiated gastric cancer . 4.PTEN p53 nm23 and bcl-2 co-assay was valuable to predict the prognosis of patients.