Abstract
The immunoreactivity of ras p21 protein product (p21) was examined in 66 freshly obtained colorectal cencer tissues and in 75 normal colon mucosa using the anti-v-H-ras p21 monoclonal antibody (Y13-259). The aim of this study was to define the clinical significance of overexpression of p21 for colorectal carcinoma. Positive staining (overexpression) of p21 was detected in 33 out of 66 cancer tissues, whereas only 7 out of 75 samples from normal colon mucosa stained positively. The difference was significant (p<0.01). There was no correlation between the overexpression of p21 and the clinical stages of colo-rectal adenocarcinomas. Survival of patients or recurrence of the disease did not differ between 33 patients with tumors stained positively for p21 and 33 patients with tumors showing negative immunoreacitivity.
These results suggested that the overexpression of p21 is implicated in malignant transformation of colorectal mucosa, but has no prognostic singnificance for patients with colorectal adenocarcinoma.