Flow cytometric DNA and 5'-nucleotide phosphodiesterase in endometrium

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)/microgram 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.

Rearrangement of chromosome 1 is a frequent finding in endometrial carcinoma. An in situ hybridization study in nine endometrial carcinomas

Nine endometrial carcinomas were examined for numerical aberrations of the chromosomes 1,7, and X by fluorescence in situ hybridization using highly repetitive chromosome-specific probes. In addition, a combination of a centromeric and a telomeric chromosome 1 probe was applied to detect structural chromosome 1 aberrations. Chromosome aberrations were found in six tumors. In four of these, an imbalance between 1q12 and 1p36 was detected, indicating the presence of an extra 1p- chromosome. In regard to the chromosomes 7 and X, monosomies and trisomies were found. Intratumoral genetic heterogeneity in endometrial carcinomas was detectable by FISH and flow cytometry. In conclusion, our findings confirm that chromosome 1 is frequently involved in structural chromosome changes, indicating chromosome 1 to be of importance in the evolution of endometrial carcinoma.

The relation between the results of cytophotometric examination of endometrial carcinoma and clinical course of these disease

We made a prospective cytophotometric study of 48 cases of endometrial carcinoma. Thirty-two (66.7%) of the cases had diploid DNA content and the proportion of non-diploid tumors increased with the staging of tumors, lack of differentiation and depth of myometrial invasion. DNA content (AE), DNA malignancy grade (DNA-MG) and 5c exceeding rate were statistically significant in relation to the clinical course of the disease and the histological grade of differentiation. DNA parameters appear to be especially suitable for the objective assessment of malignancy.

Steroid receptors and proliferative activity in non-neoplastic and neoplastic endometria

In the glands of cyclic endometria, proliferative activity (PA), as revealed by expression of the Ki-67 antigen, is highest in the proliferative phase (P) and early secretory phase (S1). The PA decreases in the middle secretory phase (S2). In the stroma the PA is low during the whole cycle. In P and S1, the oestrogen receptor (ER) and the progesterone receptor (PR) are strongly expressed in glands and stroma. The number of positive cells and the staining intensity decreases in S2, particularly in the glands. In atrophic endometria, fibro-glandular polyps and in endometria with arrested secretion the PA is low in both glands and stroma. ER and PR can be detected in glands and stroma. The PA in atypical hyperplasias is only slightly higher than in cyclic endometria and endometria with simple hyperplasia. The ER and PR levels are comparable to those in proliferative endometria. The PA of endometrial adenocarcinomas is positively and the ER and PR negatively correlated with the degree of de-differentiation. No ER-negative carcinoma displays the PR. Immunohistologically, non-neoplastic receptor positive tissue can be seen in many ER- and PR-negative carcinomas. These structures may falsify the biochemical receptor analysis.

Serous papillary adenocarcinoma of the endometrium. Analysis of proto-oncogene amplification, flow cytometry, estrogen and progesterone receptors, and immunohistochemistry

Primary and metastatic tumor tissues of serous papillary adenocarcinoma of the endometrium were examined for the following: (1) amplification of int-2, c-erbB-2 and c-myc proto-oncogenes by Southern blot hybridization; (2) DNA ploidy by flow cytometric study; (3) and expression of specific proteins, such as estrogen and progesterone receptors, keratin, vimentin, and carcinoembryonic antigen (CEA) using immunohistochemical and biochemical techniques. Amplification of c-myc was observed in the specimens from the endometrium (ten-fold) and from omental metastasis (five-fold). Both int-2 and c-erbB-2 amplification were not observed. The tumor showed aneuploidy, with the specimens from the endometrium and omental metastasis exhibiting multiple populations of aneuploid tumor cells. Estrogen and progesterone receptors could not be detected biochemically; however, immunohistochemically, estrogen receptors were observed in tumor cells forming papillary structures but not in the tumor cells of the solid, more poorly differentiated areas. A similar distribution was observed for both low and high molecular weight keratin. The findings of c-myc amplification and aneuploidy in the serous papillary adenocarcinoma of the endometrium are consistent with its aggressive behavior observed clinically and emphasize the importance of distinguishing this lesion from other types of endometrial carcinoma.