Expression of cyclin D1 and p21(WAF1/CIP1) in human gastric carcinoma and its clinicopathologic significance.
e15114 Background: The deregulation of cyclin, cyclin-dependent kinases (CDKs) and their inhibitors could have a crucial role in the development of diverse human cancers. Alterations in cell cycle regulators and subsequent deregulation of the cell cycle are frequently involved in tumorigenesis and/or tumor progression. The aim of our study was to detect the abnormal expression of cyclin D1 and p21(WAF1/CIP1)in gastric carcinoma and investigate its clinicopathologic significance. Methods: Proteins of cyclin D1 were detected by immunohistochemistry in 80 cases of advanced gastric carcinoma, and 30 cases of benign gastric diseases (chronic gastritis, atrophic gastritis, gastric metaplasia, and gastric dysplasia). From each patient formaldehyde–fixed paraffin sections were stained and examined by immunohistochemistry using monoclonal antibodies.All tumor cells with distinct nuclear staining were considered positive. Results: Sixty-five patients were male and forty five female. Normal gastric epithelium showed consistently positive immunostain for p21WAF1/CIP1. Loss of p21WAF1/CIP1 expression was noted in 65% of intestinal type adenocarcinoma and in 90% of diffuse type adenocarcinoma. Overexpression of cyclin D1 was detected in 90% of advanced gastric carcinomas. Among the various clinicopathological findings, overexpression of cyclin D1 was associated with lymph-node metastasis (P=0.003) and recurrence (P=0.044). Loss of p21WAF1/CIP1 expression was more frequent in diffuse type cancers (P=0.005) and was correlated with recurrence (P=0.002) and death (P=0.001). Conclusions: These findings suggest that overexpression of cyclin D1 is a frequent finding in gastric cancer and immunohistochemical analysis for cell cycle regulators, might be a useful prognostic indicator in gastric cancer.