Kuniaki Nakayama

Stepwise abnormality of sex steroid hormone receptors, tumor suppressor gene products (p53 and Rb), and cyclin E in uterine endometrioid carcinoma.

In the normal cell cycle, the appropriate interaction of factors such as tumor suppressor gene products (retinoblastoma susceptibility [Rb], p53) and cyclins is essential. Abnormalities in the interaction of these factors may result in malignant transformation of the cell. Malignant transformation of the endometrium, which is believed to be a sex steroid‐dependent tumor, probably involves a process of uncoupling of these factors and sex steroid hormone receptors. This study is designed to test this hypothesis.

A comparative study of pre-operative procedures to assess cervical invasion by endometrial carcinoma

Objective To compare the accuracy of different diagnostic procedures currently used to assess cervical involvement in endometrial carcinoma.

The number of proliferating cell nuclear antigen positive cells in endometriotic lesions differs from that in the endometrium. Analysis of PCNA positive cells during the menstrual cycle and in post-menopause.

Immunohistochemical expression of proliferating cell nuclear antigen (PCNA) was studied in the endometrium and in endometriotic lesions during the menstrual cycle and in post-menopausal patients. During the menstrual cycle, in the basal layer of the endometrium, an increase in the number of positive indices (PI) of PCNA was observed in epithelial cells from the menstrual phase. It reached a maximum in the proliferative phase and decreased in the secretory phase. However, no change was observed in the stromal cells of the basal layer. In the functional layer of the endometrium, the PI of the epithelial cells showed a high peak in the late proliferative phase, decreased sharply in the secretory phase and remained unchanged thereafter. The PI of the stromal cells in the functional layer showed two peaks, one in the late proliferative and the other in the mid and late secretory phase. In the endometriotic lesions, except for the proliferative phase, the number of PI was significantly higher than that of the corresponding endometrium and no significant changes were observed during the menstrual cycle. In post-menopausal endometriotic lesions, the number of PI was also higher than that of the corresponding endometrium. Thus the numbers of PI differed between the endometrium and endometriotic lesions in the same patients. These results imply that the endometriotic lesions are constantly more proliferative than the endometrium irrespective of the hormonal milieu during both the menstrual cycle and in a post-menopausal environment.

Demonstration of focal p53 expression without genetic alterations in endometriotic lesions

Their monoclonal origin (as indicated by recent investigations) indicates the neoplastic nature of most endometriotic lesions. p53, a representative tumor suppressor, regulates cell proliferation, and genetic alterations in p53 are involved in carcinogenesis in a wide variety of human cancers. The aim of this study was to examine endometriotic lesions for p53 expression and genetic alterations in p53. An immunohistochemical study revealed that 20% (13/64) of endometriotic lesions showed focal p53 expression in the epithelial cells. Using serial paraffin sections, we employed a microdissection method to extract DNA from the endometriotic tissues that showed p53 expression. No mutations were found in exons 5–8 in p53 by cleavase fragment length polymorphism scanning and polymerase chain reaction-DNA sequencing. Moreover, neither loss of heterozygosity nor microsatellite instability was detected at the microsatellite marker sites of p53. These results suggest that the focal p53 expression recognized in the endometriotic epithelia may be due to overproduction of wild-type p53 protein.

Immunohistochemical analysis of the peritoneum adjacent to endometriotic lesions using antibodies for Ber-EP4 antigen, estrogen receptors, and progesterone receptors: implication of peritoneal metaplasia in the pathogenesis of endometriosis

This study was designed to investigate whether or not the pelvic peritoneum exhibits a metaplastic process into müllerian-type epithelium using a marker for epithelial differentiation (Ber-EP4 antigen) and markers that indicate müllerian differentiation (estrogen receptors and progesterone receptors). The peritoneum and/or ovarian surface epithelium adjacent to endometriotic lesions were obtained from 24 patients with endometriosis at operation, and peritoneum and ovarian surface epithelium without any lesions were also obtained from control patients without endometriosis. The specimens were immunohistochemically analyzed using antibodies for epithelial antigen Ber-EP4, estrogen receptor (ER), and progesterone receptor (PR) on frozen sections. Normal peritoneal mesothelium showed negative staining for Ber-EP4, ER, and PR. The mesothelium of the peritoneum adjacent to the endometriotic lesions showed focal positivity for Ber-EP4, ER, and PR. Several cases of ovarian surface epithelium from normal control ovaries and ovaries adjacent to endometriotic lesions also showed focal positivity for Ber-EP4, ER, and PR. Stromal cells accompanying these foci were sporadically positive for ER and/or PR but negative for Ber-EP4. Focal expression of Ber-EP4, ER, and PR in the mesothelium of the peritoneum and the ovarian surface epithelium adjacent to endometriotic lesions suggests that mesothelium possibly acquires characteristics of epithelial as well as müllerian-type nature. These results support an existence of a metaplastic process of the peritoneal mesothelium in the pathogenesis of endometriosis. The more frequent Ber-EP4 positivity in normal ovarian surface epithelium compared to normal peritoneal mesothelium also suggests a fundamental difference in these tissues that may be related to the greater prevalence of epithelial neoplasms arising in ovarian tissue.

Abnormal Expression of Sex Steroid Receptors and Cell Cycle-related Molecules in Adenocarcinoma in Situ of the Uterine Cervix

It was recently reported that cervical adenocarcinoma showed an abnormal expression of estrogen receptor (ER) and cell cycle-related molecules (cyclin E, p53, p16, p21, and p27). To investigate whether similar alterations exist in glandular intraepithelial lesions, the expression of ER, progesterone receptor (PR), Ki-67, and the above cell cycle-related molecules was examined in 15 cases of glandular dysplasia (GD) and 10 cases of adenocarcinoma in situ (AIS), using the immunohistochemical technique. An expression of ER and PR was often decreased or missing in GD and, especially, in AIS. The Ki-67 labeling index was significantly higher in AIS than in GD or normal glandular cells. In GD, expression of all the cell cycle-related molecules was not recognized (except for a few p27-positive cases), a situation comparable to normal glands. In contrast, an abnormal expression of all the cell cycle-related molecules examined was demonstrated in AIS. There was a significant positive correlation, in terms of the extent of staining, between cyclin E and p21 in AIS. These results suggest that an altered expression of these molecules occurs in AIS as it does in invasive adenocarcinoma, and provide additional evidence supporting AIS as a precursor of cervical adenocarcinoma.

Immunohistochemical analysis of CA125, CA19–9, and Ki-67 in stage III or IV endometriosis: positive correlation between serum CA125 level and endometriotic epithelial cell proliferation

Background. Serum levels of CA125 and CA19–9 are often elevated in patients with endometriosis, but the clinical or biological significance of this is not well established. The aim of the present study was to compare serum and tissue levels of CA125 and CA19–9, and to examine the correlation between these levels and cell proliferation using immunohistochemical analysis in stage III or IV endometriosis.Methods. Forty-five cases diagnosed histologically as endometriosis were analyzed (26 cases were stage III and 19 were stage IV using the revised American Fertility Society classification). The preoperative serum levels of CA125 and CA19–9 were measured by immunoradiometric assay. Immunohistochemical analysis was performed using antibodies against CA125, CA19–9, and Ki-67 (a representative marker of cell proliferation).Results. The serum levels of CA125 and CA19–9 were elevated (over the cutoff values) in 25 cases and 21 cases, respectively. There was no significant correlation between serum CA125 and serum ...

Proliferative activity of postmenopausal endometriosis: a histopathologic and immunocytochemical study.

Histological features of 21 cases of postmenopausal endometriosis as well as the corresponding eutopic endometrium were studied. Immunocytochemical analysis of estrogen receptor (ER), progesterone receptor (PR), and Ki-67 nuclear antigen was also performed on the endometriotic lesions as well as the corresponding endometrium. All the cases studied were complicated by various other gynecologic diseases, making the preoperative diagnosis of endometriosis unlikely. Histologically, the endometriotic foci contained both epithelial and stromal components mostly lacking atrophic features in contrast to the corresponding eutopic endometrium. The endometriotic lesions and the corresponding endometrium exhibited immunoreactivity with ER in both the glands and stroma. The stromal cells of endometriotic lesions revealed positive PR staining, whereas those of the eutopic endometrium were either negative or weakly positive for PR, but the epithelial components of both were positive for PR. The positivity of Ki-67 antigen tended to be higher in the stroma of the postmenopausal endometriosis than in the eutopic endometrial stroma. Endometriotic lesions appear to remain biologically active, with proliferative activity as well as retained hormonal responsiveness, even in the low-estrogen milieu of the postmenopausal age.

Proliferative Activity and Genetic Alterations in TP53 in Endometriosis

In the secretory phase of the menstrual cycle, proliferative activity and expression levels of cell cycle-regulatory molecules are higher in endometriotic lesions than in the corresponding eutopic endometrium. In some endometriotic lesions, proliferative activity remains high in the postmenopausal period. By immunostaining, one can recognize TP53 overexpression in epithelial cells in a considerable number of endometriotic lesions. In those endometriotic lesions that show TP53 overexpression, neither TP53 point mutations (exons 5 to 8) nor microsatellite alterations (microsatellite instability or loss of heterozygosity) has been detected. Thus, the TP53 overexpression demonstrated in endometriotic epithelia seems to result from an overproduction of wild-type TP53 protein. The biological role of TP53 in endometriotic lesions is still unclear.

Genetic alterations in microsatellite marker sites among tumor suppressor genes in endometriosis

Four endometriotic lesions were examined for the presence of genetic alterations in microsatellite marker sites among eight tumor suppressor genes. For this, a microdissection method was used on paraffin sections. Only one instance of loss of heterozygosity was detected at the PTCH locus. Heterozygosity was retained (indicating the absence of both loss of heterozygosity and microsatellite instability) at the other seven tumor suppressor gene loci in all the cases. Among the tumor suppressor genes examined, genetic defects in these microsatellite regions are certainly not ubiquitous in endometriosis and may be uncommon.