p53 overexpression and steroid hormone receptor status in endometrial carcinoma

Mutations of the p53 tumor suppressor gene often occur in a variety of human malignant tumors and are frequently associated with overexpression of p53 protein. This study was designed to examine indirectly the frequency of p53 protein in primary endometrial carcinoma and to correlate the overexpression with steroid hormone receptor status including pS2 protein status. The study was performed on 79 formalin-fixed, paraffin-embedded tissues of endometrial carcinoma. P53 protein overexpression was detected by means of immunohistochemistry using monoclonal antibody NCL-p53-DO7. Estrogen and progesterone receptor status was determined by immunohistochemistry using the monoclonal antibodies NCL-ER-LH2 and NCL-PGR, respectively, and the pS2 protein using polyclonal antibody NCL-pS2. Overexpression of p53 protein was found in 27 (34%) of the 79 endometrial carcinomas. A strong positive relationship was demonstrated between histologic grade and p53 protein overexpression. There was a significant correlation between p53 protein overexpression and negative estrogen receptor status (49%) negative progesterone receptor status (49%) as well as a negative pS2 protein (45%). The results suggest that overexpression of p53 is associated with high malignant potential. However, p53 overexpression itself does not appear to be an independent prognostic factor in endometrial carcinomas.