Expression of p21 and p53 Proteins in Gastric Adenocarcinoma

ABSTRACT

Fifty-four adenocarcinomas of stomach were investigated to assess the expression of p21 and p53 using an immunohistochemical method. The relationship between p21 and p53 expression and the clinicopathologic parameters were analysed. The staining pattern of p21/p53 were: p21+/p53+, p21-/p53+, p21+/p53-, and p21-/p53- in 30, 12, 8, and 4 cases, respectively. Loss of p21 expression was observed in 16 of 54 tumor tissues (29%). p21 expression, however, had an inverse correlation with vascular invasion and depth of tumor invasion. The p21 and p53 protein expression showed intratumoral heterogeneity. In 63% of the adenocarcinoma, a proportional relationship was found between p21 and p53 immunostaining. The present results suggest that p53 independent induction of p21 expression may be involved in the molecular mechanism of these tumors, and expression of p21 protein may be related to a favorable prognosis in gastric adenocarcinomas.