Flow cytometric cell cycle kinetics and quantitative measurement of c-erbB-2 and mutant p53 proteins in normal, hyperplastic, and malignant endometrial biopsies

Objectives: The purpose of this study is to biologically characterize endometrial hyperplasia by investigating changes in DNA ploidy pattern, the expression of c-erbB-2 p185 and mutant p53 proteins. Methods and Results: Our results show that all normal endometria ( n = 62) were exclusively diploid and 2 (2.5%) of 79 endometrial hyperplasias and 22 (68.8%) of 32 endometrial carcinomas were aneuploid. Upper 95% normal values for synthetic phase fraction (SPF), c-erbB-2 and p53 were applied as cut-off values to discriminate between normal and malignant endometria. When 9%, 3.2 HNU (Human Neu Unit)/μg protein, and 0.39 ng/mg protein were used as cut-off values for SPF, c-erbB-2, and p53 respectively, 13.9%, 20.2%, and 0% of endometrial hyperplasia and 50%, 56.3%, and 12.5% of endometrial carcinoma showed raised levels of the corresponding parameters. Conclusions: Our results indicate that subsets of endometrial hyperplasia are biologically different as evidenced by the presence of DNA aneuploidy, high SPF and c-erbB-2 overexpression, which may provide biological markers for assessing progression to endometrial carcinoma.