DNA content of human endometrial gland cells during the menstrual cycle

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.

Trout and salmon erythrocytes and human leukocytes as internal standards for ploidy control in flow cytometry

Control of technique and use of biological standards in flow cytometry have become increasingly important due to the wider use of the method for ploidy determination of malignant tumors in clinical research. Trout (TRBC) and salmon erythrocytes and human buffy coat leukocytes were selected for a study of factors influencing the DNA stainability. Whether standard and test cells were mixed before or after enzymatic treatment and staining was found to be critical for the ploidy comparisons. Otherwise, artifactual differences of at least 20% may be noted, leading to an overestimation of DNA aneuploidy. The time from staining to analysis had minimal effect, with some exceptions. The proportions of different cells in the sample had no influence, and nonlinearity of measurements was negligible. Diploid cells in normal endometrium and benign ovarian tumors, as well as the diploid fraction of aneuploid tumor cells, were systematically measured to have a DNA staining 5-7% above human leukocytes.

Nuclear DNA content of clear cell adenocarcinoma of the vagina and cervix and its relationship to prognosis

A study was performed to determine if ploidy levels of nuclear DNA content could be used as a prognostic index of the biologic behavior of clear cell adenocarcinoma of the vagina and cervix in young females. Forty tumors were examined. Four patterns of nuclear DNA distribution were identified: (1) peridiploid stem cell lines (2N to 3N); (2) peritetraploid stem cell lines (3N to 5N); (3) hypertetraploid stem cell lines (greater than 5N); and (4) highly aneuploid without detectable stem cell lines. Tumors having peridiploid and peritetraploid stem cell lines (low ploidy group) were most often clinical Stage I or II (87%) and were in general associated with a favorable prognosis. Tumors having hypertetraploid stem cell lines and highly aneuploid distribution (high ploidy group) were usually clinical Stage III or IV (65%). Clinically advanced tumors (Stage III or IV) had poor prognosis irrespective of ploidy level. Among the clinical Stage I and II tumors, the low ploidy group had a slightly better prognosis than the high ploidy group. This difference, however, was not statistically significant.

DNA-flow-cytometric measurements on the normal, atrophic, hyperplastic and neoplastic human endometrium

DNA distribution patterns and the fractions of the cell cycle phases were determined by means of flow-through cytometry in 87 samples of normal, atrophic, hyperplastic and carcinomatous human endometrium. The S-phase fractions vary during the normal menstrual cycle between 1 and 3% and reach a periovulatory maximum between 4.4 and 4.7%. Atrophic endometrium and regressive glandular cystic hyperplasia have little DNA synthesis (1.01% and 1.68% S-phase fractions respectively). Proliferating glandular cystic hyperplasia reveals 3.38% S-phase fraction, whereas adenomatous hyperplasia has an increased number of DNA-synthesizing cells (4.81%). The well-differentiated endometrial carcinoma shows no cytophotometrically detectable differences in comparison to adenomatous hyperplasia. All endometrial samples except for poorly differentiated endometrial carcinoma showed a diploid to tetraploid DNA distribution pattern. The poorly differentiated endometrial carcinoma displays two different types: one rapidly growing diploid-tetraploid tumor with 8.0 to 9.6% S-phase fractions, and another type with stemline deviations, polyploid nuclei and less pronounced synthetic activity.

Proliferation kinetics of human endometrium during the normal menstrual cycle

A radioautographic analysis of the number and distribution of labeled nuclei after in vitro incorporation of radiothymidine was carried out in human endometrium during the normal menstrual cycle. The highest rates of proliferation were recorded on cycle days 8 to 10 in the upper one third of the functionalis layer. Coinciding with intraglandular secretory activity on cycle day 19, the rate of proliferation of gland cells decreased near zero levels and remained unchanged thereafter. Midsecretory phase arteriolar coiling and stromal predecidualization were associated with increased isotope incorporation. DNA synthesis in premenstrual endometrium was limited to the surface epithelium, predecidua, and vascular endothelium. The endometrium of the isthmus and cornual regions and of the basalis zone demonstrated relatively constant and comparatively lower rates of proliferation throughout the cycle. Regional and cellular variations in nucleic acid synthesis in cyclic endometrium are likely to reflect differences in physiologic functions in target cells in response to cyclic hormonal stimuli.

The diagnosis of endometrial carcinoma by means of jet wash and DNA flow-through cytophotometry

Flow-through cytophotometric determination of nuclear DNA content on jet wash material from the endometrium was employed in the diagnosis of endometrial carcinoma. One hundred and thirty cases were studied. In comparison to results from cytodiagnosis, flow-through photometry yielded a false negative rate of 31.6% and a false positive rate of 42.2%. The false negative findings resulted in part from the small relative frequency of atypical cells in a mixed population of normal and atypical cells in certain cases. Besides this, we often found carcinomas with a diploid DNA stem line, which could not be distinguished cytophotometrically from normal corpus endometrium (Sandritter, 1952; Atkin et al., 1959; Hustin, 1976). The flow-through photometrically false positive findings may have resulted either from cell aggregates or from a nuclear DNA content elevated over the diploid value in proliferating cells (D. Wagner et al., 1968; D. Wagner and Richard, 1968). The observed false negative and false positive rates demonstrate that flow-through photometric determination of nuclear DNA content is unsuitable for the diagnosis of endometrial carcinoma.

The ultrastructure of polyploid B-cells in the islets of normal mice

Light and electron microscopic studies of diploid, tetraploid and octaploid B-cells in the islets of normal C57BL/KsJ mice revealed that polyploid cells were characterized by a wider range of granulated states than diploid B-cells. The maximum granule densities were similar for polyploid and diploid cells; however, some polyploid cells were almost devoid of granules, while the least granulated diploid cells contained intermediate granule densities. The tetraploid cell also appeared to be characterized by an increased mitochondrial stage which suggests compensation for the greater degree of degranulation. These observations were confirmed by morphometric analysis. Two interpretations of the apparent polyploidy are discussed; that polyploid B-cells may be more responsive to insulin releasing stimuli than diploid B-cells and that tetraploid cells may only be diploid cells in the G2 phase of the mitotic cycle.

Studies on the cytodynamics of human endometrial regeneration. I. Scanning electron microscopy

Stereoscopic morphologic studies on regenerating cyclic endometrium indicate that endometrial repair lasts 48 hours, beginning between cycle Days 2 to 3 and ending between cycle Days 4 to 5. During this period, endometrial repair is focused on the neoformation of surface epithelium and is initiated only when and where the zona basalis is denuded from the overlying secretory spongiosa. The surface epithelium is derived from a simultaneous proliferation of dual origin: first from the exposed ends of basal glands and second from the persistent and intact surface lining of cornual and isthmic regions, bordering the denuded areas. The lack of estrogen-dependent morphologic alterations (mitosis and ciliogenesis) in the uterine mucosa during the regenerative period suggests that the initial factors and cellular processes operating in endometrial reconstruction are purely a reflection of tissue repair and are independent of cyclic hormonal stimuli.