Expression of EGF, EGF‐receptor, p53, v‐erb B and ras p21 in colorectal neoplasms by immunostaining paraffin‐embedded tissues

Abstract

Immunohistochemical studies were performed to clarify the significance of the expression or overexpression of epidermal growth factor (EGF), EGF-receptor (EGFR), p53, v-erb B, ras p21 in 23 cases each of tubular adenoma and adenocarcinoma. The expression of EGF, EGFR, p53, v-erb B, and ras p21 in paraffin-embedded tissues, from 46 patients with colorectal tumors (adenoma: 23 cases; 14 mild dysplasia, six moderate dysplasia, three severe dysplasia, adenocarcinoma: 23 cases; 17 well differentiated, two moderately differentiated, three poorly differentiated, one mucinous carcinoma was analyzed immunohistochemically using anti-EGF, EGFR, p53, v-erb B and ras p21 antibodies. The EGF and ras p21 tended to express more strongly in carcinoma cases than in the adenoma cases, and in severe and moderate dysplasia than in mild dysplasia (EGF: stained positive in five adenomas [21.74%] and 17 adenocarcinomas [73.91%]; ras p21: stained positive in six adenomas [26.09%] and 14 adenocarcinomas [60.87%]. The EGFR stained positive in two adenomas (8.70%) and two adenocarcinomas (8.70%). The p53 and v-erb B showed positive staining only in the carcinoma cases (p53: stained positive in four cases [17.39%]; v-erb B: stained positive in eight cases [34.78%]). This study suggests that these factors seem to have some role in the progression of colon neoplasms. It suggests that genetic alteration is not always equal to the overexpression of protein products, but that it reflects them well, and that the staining makes some contribution to differential diagnosis in colorectal neoplasms.