Clinical Significance Of Fas/FasL, P27 And PCNA Expression In Gastric Cancer

Objective.To study the relation between the expression of Fas/FasL and clinicopathological characteristics in different location tissue of gastric cancer and the expression of P27,PCNA in gastric cancer.In order to investigate the influnce of Fas/FasL P27 and PCNA on gastric tumorigenesis and development.Methods:50 gastric cancer specimens and 10 cases of normal gastric mucosa were collected and continuous paraffin slices were made from the normal gastric mucosa ?5cm distance from gastric cancer tissue,paracarcinoma tissue and gastric cancer tissue of each specimen.The expression of Fas/FasL were analyzed with immunohistochemistry SP method in order to find the difference in the above-mentioned tissues.Immunohistochemistry staining was also used to detect P27,PCNA in the above-mentioned normal gastric tissue and gastric cancer tissue. All data were tested by X2test or / test.Results:There was high expression positive rate for Fas (100% ) in normal gastric mucosa, but there was no expression for FasL. Compared with gastric cancer tissue,paracarcinoma tissue and normal gastric mucosa,theFas expression positive rate(50%vs60%vsl00%)and the FasL expression positive rate(58%vs46%vsO)also showed significant difference (P<0.05) .Fas antigen expression in gastric carcinoma tissues was less than in paracarcinoma tissues (P>0.05), FasL expression in gastric carcinoma tissues was higher than in paracarcinoma tissues (P> 0.05 ) .Compared with normal gastric mucosa and 5cm distance from gastric carcinoma tissue the Fas expression positive rate(100%vs96%)and the FasL expression positive rate(0vs4%)also showed no significant difference(P>0.05). The expression positive rate of Fas and FasL was 26 % ; The expression negative rate of Fas and FasL was 30%; The expression negative for Fas and positive for FasL was 20%; The expression positive for Fas and negative for FasL was 24%.The expression of Fas/FasL was not associated with tumor grade, stage and metastases in lymph nodes.P27 high expression rate for normal gastric mucosa was 80%,but for gastric cancer tissue was 28%.The PCNA LI in normal gastric mucosa and gastric cancer tissue was(18.56+ 4.17)and(52.34+16.32).They also showed significant difference in normal tissue and gastric cancer tissue (P< 0.01) .The PCNA LI was significantly lower in the cases whose cancer cells were characteristic of well-differentiation, histologic I II grade, and without lymphnode metastasis than those of poor or un-differentiation, histologic III, IV grade, and withlymphnode metastasis.In gastric cancer the expression of PCNA and P27 was correlated with the degree of differentiation,TNM stage and metastases in lymph nodes.The PCNA LI were higher in gastric carcinoma tissues with expression positive of FasL than those with expression negative of FasL; The PCNA LI were higher in gastric carcinoma tissues with expression negative of Fas and low expression of P27 than those with expression positive of Fas and high expression of P27.The high PCNA LI was associated with low expression of Fas P27 and high expression of FasL. We discovered 9 cases whose expression of Fas FasL P27 were all abnormal , they had poor-differentiation, higher malignant and with lymphnode metastasis. It showed that test of multiple gene in step may more correctly predict prognosis.ConclusionrDown-regulation of Fas and Up-regulation of FasL are associated with the evolution of gastric cancer.Fas/FasL system may play an important role of immune-privilege in the development and progression of gastric cancer. Fas/FasL are involved in gastric tumorigenesis, but may not be related with gastric carcinoma progression. The results suggest that the expression of Fas/FasL in gastric carcinoma belong to the neoplasm biologic property, that is, the escape of tumor cells from body immune function.The mechenism is multiple and complex.The expression of P27 in gastric cancer issignificantly associated with clinicopathological characteristics and P27 may be an important factor to prognosis of gastric cancer. The gastric c...