Expressin of p16 protein in gastric carcinoma and precancerous lesion

Objective To study the role of p16 gene in gastric carcinogenesis and the relation between the gene expression and the behavior of gastric carcinoma . Method p!6 protein was detected with immunohistochemical ABC method in 10 normal gastric mu-cosas, 42 gastric mucosal dysplasias , 16 early and 52 advanced gastric carcinomas . Results All normal gastric mucosas were positive for p16 protein. The positive rates in dysplasias and gastric carcinomas decreased gradually with the progession of lesions . The positive rates were 87.5% , 75% and 50% in slight , moderate and severe dysplasias respectively, 43.8% positive rate was found in early gastric carcinomas and 38.5% positive rate in advanced cases.The rate in slight dysplasias was significantly higher than that in severe dysplasias , early and advanced gastric carcinomas, (P0.05 respectively); and the rate of moderate dysplasias was signicantly higher than that of advanced gastric carcinomas (P0.05). The rate of the group with lymph node metastasis was much lower than that without metastasis (22.2% vs 51.2%, P0.05).Conclusion The loss of p16 expression is closely related to gastric mucosal carcinogenesis, and p16 protein may be an useful marker for the assessment of the biological behavior of gastric carcinoma.