Immunohistochemical analysis of estrogen receptor alpha, estrogen receptor beta and progesterone receptor in normal human endometrium

The endometrium expresses estrogen (ER) and progesterone receptors (PR), which are involved in autocrine and paracrine regulation processes in response to estrogen and progesterone. The aim of the present study was to evaluate immunohistochemical distribution patterns of estrogen receptor alpha (ER alpha), estrogen receptor beta (ER beta) and PR in normal human endometrial tissue with the use of monoclonal antibodies. Human endometria were obtained from 17 premenopausal patients undergoing surgery for non-malignant diseases and were classified to be in proliferative, early secretory and late secretory phases by histological and anamnestical means. Distribution patterns of the steroid receptors were evaluated using the IRS-score and the Mann-Whitney rank-sum test was used to compare the means. Correlation was assessed with the Spearman factor and linear regression analysis. ER alpha and PR expression decreased significantly (p<0.05) in glandular epithelium from the proliferative to the late secretory phase. ER beta expression showed a similar significant decrease (p<0.05), although staining intensity was lower than that of ER alpha. A significant correlation between expression of all three steroid receptors was observed (p<0.001). Distribution patterns of ER alpha, ER beta and PR in normal human endometrium showed a cyclic variation during the menstrual cycle. A significant correlation between expression of ER alpha, ER beta and PR was also demonstrated using regression analysis, indicating dependence of expression of these three steroid receptors. The present study shows the presence of steroid receptors in human endometrial epithelium, indicating that these cells respond to estrogen and progesterone and thus playing a significant role in endometrial physiology.     

Expression of leukocyte adhesion molecules in human endometrium

In the present investigation the distribution of molecules that are involved in the leukocyte binding was studied in human endometrium. The expression of intercellular adhesion molecule-1 (ICAM-1), lymphocyte function-associated antigen (LFA-1), and HLA-DR molecules was studied in 13 proliferative and 10 secretory endometria as well as cultures of endometrial glands and stroma by avidin-biotin complex (ABC) procedure using monoclonal antibodies. The ICAM-1 and HLA-DR molecules were both strongly expressed in the lymphoid and endothelial cells. ICAM-1 expression was uniform in the epithelium, whereas the HLA-DR molecules were preferentially expressed in the epithelial cells in the basalis. Expression of both epithelial HLA-DR and ICAM-1 molecules was enhanced adjacent to lymphoid aggregates. ICAM-1 molecule was uniformly expressed in the stromal cells in the basalis and the functionalis, whereas the HLA-DR molecules were expressed exclusively in the stromal cells surrounding the lymphoid cells. ICAM-1 expression in the epithelial and stromal cells was confirmed in the isolated intact stromal cells and glands by immunohistochemistry. Although stromal and epithelial cells propagated in vitro expressed ICAM-1, they were rarely HLA-DR positive. The expression of LFA-1 was confined to the lymphoid cells. The high level of expression of ICAM-1, LFA-1, and HLA-DR molecules in human endometrial constituents may contribute to the presence, aggregation, and preferential distribution of lymphoid cells in human endometrium.     

Variable expression of Ia antigens in human endometrium and in chronic endometritis

Recent studies suggest that Ia antigens may be expressed in epithelial cells and that their expression may be under hormonal control. Therefore, the distribution of these antigens was studied in frozen sections of 37 human endometria with two monoclonal antibodies (Mab) to monomorphic determinants of Ia antigens using an avidin-biotin-complex (ABC) method. Five early proliferative, 9 midproliferative, 3 late proliferative, and 12 secretory endometria were examined. Two gestational endometria and six endometria with chronic endometritis were also used. Four consecutive sections from each case were stained for Ia, OKT8, Leu-3a, and B1 antigens. Throughout the cycle, the endothelial cells, many lymphocytes, and various monocytic-macrophagic cells in endometrial stroma were Ia positive. Furthermore, Ia antigens were localized to the normal endometrial epithelium. The intensity and the pattern of Ia expression, however, varied in different phases of the cycle. Ia antigens were stained weakly in endometrial glands and surface epithelium in early proliferative phase, and strongly in surface epithelium and glandular cells of the basalis and to a lesser extent of the functionalis in midproliferative and late proliferative phases. The expression of Ia antigens in epithelium was absent or focal during the secretory phase and in gestational endometria. Throughout the cycle and in gestational endometria, glandular cells in intimate association with lymphocytic aggregates were Ia positive. In chronic endometritis, the increased number of Ia positive stromal lymphoid cells was associated with a strong display of Ia antigens in epithelium. The findings indicate that, in addition to endothelial and lymphoid cells, Ia antigens are expressed in endometrial glandular and surface epithelial cells. This expression may be influenced by lymphoid cells in endometrium and by hormones.     

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

Summary 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 comaparable 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, nonneoplastic receptor positive tissue can be seen in many ER- and PR-negative carcinomas. These structures may falsify the biochemical receptor analysis. Prof. Dr. Curt Froboese dedicated to his⁹⁹th birthday     

Immunocytochemical study of progesterone receptors in the human endometrium during the menstrual cycle

Specific mouse monoclonal antibody (alpha PR6) against progesterone receptor was used with an avidin biotin complex technique to localize progesterone receptors in frozen sections of 26 normal cyclic human endometria. Progesterone receptor was detected in the nuclei of epithelial and stromal cells in both the functionalis and basalis layers. In the functionalis, the receptor content increased from the early to the late proliferative phase in both cell components. It remained high in the early secretory phase and decreased in the mid- and late secretory phases, comparatively more rapidly in the epithelium than in the stroma. In the latter, the predecidual cell nuclei were receptor-positive. The menstrual phase endometrium lacked receptors. The basalis was rich in progesterone receptors during the proliferative, early and midsecretory phases in both components and receptor-free during the late secretory and menstrual phases of the cycle. Myometrial smooth muscle cell nuclei contained progesterone receptors, whereas they were absent in endometrial and myometrial vessels. Overall, the epithelial progesterone receptor content seemed to correlate with the endometrial tissue levels of estradiol, possibly reflecting its estrogen sensitivity, whereas the stromal progesterone receptor content during the secretory phase at least, in part, may be constitutively synthetized.     

Immunoultrastructural localization of Ia antigens in human endometrium

The distribution of Ia antigens was studied at the light and ultrastructural levels in 34 proliferative and 16 secretory endometria with two monoclonal antibodies using an avidin-biotin-peroxidase complex method. The endothelial cells, many lymphocytes, and various monocytic-macrophagic cells in the endometrial stroma were Ia positive. Furthermore, Ia antigens were localized to normal endometrial epithelium in the proliferative phase, and focally in epithelium adjacent to stromal lymphoid aggregates throughout the cycle. Expression of Ia antigens in the secretory epithelium was focal or absent. At the ultrastructural level, Ia-positive epithelial cells exhibited staining on the plasma membrane, in free and membrane-bound ribosomes, rough endoplasmic reticulum, and occasional perinuclear cisternae. In the endothelial cells and lymphocytes, Ia antigens were also localized to the plasma membrane and rough endoplasmic reticulum. These findings indicate that endometrial epithelium expresses Ia antigens which may be regulated by endometrial lymphoid cells and/or hormones. The plasma membrane expression of Ia antigens by the epithelial cells of endometrium appears to result from active synthesis, and not merely from passive absorption of Ia antigens.     

The immunocytochemical distribution of leukocytic subpopulations in human endometrium.

Thirty human endometria were selected from women aged 21-54 years who had undergone routine dilation and curettage procedures for tubal ligation, infertility dating, and irregular menstrual cycling. Histologic sections of the cases chosen were examined to exclude any major pathologic condition (including chronic endometritis). The specimens were stained with monoclonal antibodies to a common leukocytic antigen (H Leu-1 and PD7/26), pan-T-cell antigen (UCHT1), T helper/inducer and T suppressor/cytotoxic antigens (Leu-3a and UCHT4, respectively), pan-B cell antigen (To15 and Leu-12), and macrophage antigens (UCHM1 and Leu-M3). Other antibodies used included TAL-1B5 (anti-HLA-DR), Leu-7 (natural killer cell) and Na 1/34 (anti-T6/Langerhans/interdigitating reticulum cell). The endometria contained significant numbers of common leukocyte antigen-positive cells (occupying approximately 10-15% of the stroma), the numbers of which appeared to increase in the late secretory/pre-menstrual phase (20-25% of the stroma). The major leukocyte populations were T cells and macrophages; the latter, with neutrophils, appeared to account for the premenstrual increase in leukocytes. T cells were distributed both diffusely in the stroma and in periglandular stromal aggregates closely applied to the glands. The T8+ suppressor/cytotoxic population was predominant within the stromal nodules. In addition, scattered intraepithelial T suppressor/cytotoxic cells were present. Macrophages (UCHM1 and HLA-DR+) were also distributed diffusely in the stroma and as part of the periglandular stromal aggregates, in areas sending long cell processes into the epithelium. B cells appeared to be limited to scattered cells in the stroma, only increasing in number within lymphoid follicles. Natural killer cells, as defined by Leu-7+ cells, were also present, scattered singly in the stroma and within lymphoid follicles. The demonstration of large mononuclear dendritic-appearing Na 1/34+ cells within the glands of the endometrium in 5/30 cases suggests the presence of T6+ Langerhans/interdigitating reticulum cells in the endometrium. Thus, the normal endometrium has an important population of immunologically competent cells. Further study of these cell populations may elucidate their contribution, if any, to pathologic conditions in the endometrium.     

Differential Expression of HLA-DR,HLA-DP,and HLA-DQ Antigenic Determinants of the Major Histocompatibility Complex in Human Endometrium

ABSTRACT: We reported on the expression of HLA-DR molecules of the major histocompatibility complex in human endometrium. We now report on the expression of two other class II molecules, the HLA-DP and HLA-DQ determinants. These molecules were localized by monoclonal antibodies in 11 proliferative and 12 secretory endometria by avidin-biotin-complex (ABC) procedure. The expression of all three molecules was invariable and consistent throughout the entire menstrual cycle in endothelial and lymphoid cells. HLA-DR molecules were expressed in endometrial epithelium, particularly in the basalis in the mid to late proliferative phases of the cycle. In contrast, through the entire menstrual cycle, the expression of HLA-DP and HLA-DQ antigenic determinants was absent, and only occasionally a focal expression of these molecules was seen in endometrial epithelium. The in vitro induction of expression of the class II molecules in human endometrial epithelial cell cultures (HEE) by IFN-gamma was dose-dependent. After treatment with low doses of IFN-gamma, these cells primarily expressed HLA-DR molecules in vitro. The differential expression of the molecules of the major histocompatibility complex in human endometrial epithelium in vivo may be due to the differential sensitivity of the epithelium in response to cytokine(s).     

Immunohistochemical expression of estrogen and progesterone receptors in endometrial polyps and adjacent endometrium in postmenopausal women

OBJECTIVE: To detect the presence of estrogen (ER) and progesterone (PR) receptors in endometrial polyps and adjacent endometrium in postmenopausal women. METHODS: Forty-four consecutively enrolled postmenopausal patients were submitted to operative hysteroscopy. These patients had diagnosed benign endometrial polyp. The presence of ER and PR was determined in endometrial samples and polyps by immunohistochemical method and the slides were evaluated using a semiquantitative analysis. RESULTS: In the glandular epithelium, the median of the ER score was 7.0 in the polyps and 5.0 in the endometrium (P<0.0001) and the median of the PR was 6.0 in the polyps and 4.0 in the endometrium (P<0.0001). In the stroma, the median of the ER score was 6.0 in the polyps and 5.0 in the endometrium (P=0.021) and the median of the PR score was 4.0 in the polyps and 4.5 in the endometrium (P=0.34 ). CONCLUSIONS: Our data suggests that steroids receptors present a crucial role in the phisiopathology of the endometrial polyps in postmenopausal women, specially the estrogen receptors.     

Hormonal regulation and localization of estrogen, progestin and androgen receptors in the endometrium of nonhuman primates: effects of progesterone receptor antagonists

This article reviews the effects of estradiol (E(2)), progesterone (P) and P receptor antagonists (PA) on the rhesus macaque endometrium. Ovariectomized macaques can be treated with implants of estradiol (E(2)) and P to induce precisely controlled, artificial menstrual cycles. During these cycles, treatment with E(2) alone induces an artificial proliferative phase marked by extensive endometrial epithelial cell proliferation and increased expression of stromal and epithelial estrogen receptor (ER) and P receptor (PR). Androgen receptor (AR) is also upregulated by E(2) but is expressed only by the endometrial stroma. Progesterone acts on the E(2) primed endometrium to induce secretory differentiation and causes suppression of epithelial and stromal ER, epithelial PR, and stromal AR in the functionalis zone. However, epithelial ER and PR are retained in the basalis zone during the secretory phase. When potent P antagonists (PA) are administered acutely at the end of an E(2) + P induced cycle, menses typically ensues similar to P withdrawal at the end of the menstrual cycle. When PAs are administered chronically there is significant blockage of all P- dependent effects including upregulation of ER, PR and AR and suppression of glandular secretory function. However, chronic PA administration also inhibits estrogen-dependent endometrial cell proliferation and growth. This endometrial antiproliferative effect is the basis of the clinical use of PA to control various diseases such as endometriosis.     

Steroid receptor expression in late follicular phase endometrium in GnRH antagonist IVF cycles is already altered, indicating initiation of early luteal phase transformation in the absence of secretory changes

BACKGROUND: Ovarian stimulation for IVF profoundly alters the early luteal phase endometrial development. It has been hypothesized that this process has already started in the late follicular phase, as the endometrium has already been exposed to high steroid concentrations since that phase. The aim of the present study was to prospectively investigate the effect of multi-follicular ovarian stimulation for IVF on the late follicular phase endometrium histology and the expression of estrogen receptor (ER) and progesterone receptor (PR). METHODS: In a cross-over study, 11 infertile women with normal ovulatory function, participating in an IVF programme and treated with GnRH antagonist/recombinant FSH ovarian stimulation, were enrolled in the study. Endometrial biopsies were taken in a natural cycle on the day of the onset of the surge of the LH, and in a subsequent stimulation cycle on the day of hCG administration for final oocyte maturation. Endometrial histological dating was carried out according to Noyes' criteria. Immunohistochemistry was performed, using commercially available antibodies for ER and PR endometrial expression. The immunohistochemical signal was recorded in 1000 epithelial cells in each compartment (glands and stroma). Endometrial expression for each of the two receptors was graded on a scale of 0-3, based on the intensity of nuclear staining. Then a score range between 0 and 3000 was recorded, and expressed as a mean score per 1000 stroma or glandular cells per sample (range: 0-3). RESULTS: Histological examination of biopsies both in natural and stimulated cycles showed no secretory changes. However, in stimulated cycles, PR expression was significantly up-regulated compared to natural cycles in both glands (1.67 versus 1.34, P < 0.05) and stroma (1.98 versus 1.62, P < 0.05), whereas ER was down-regulated in glands (1.15 versus 1.43, P < 0.05). In IVF cycles, the progesterone measurements, although within normal values (range 0.8-1.4 microg/l), were significantly higher than in natural cycles (0.99 vs 0.63 microg/l, respectively, P = 0.008). An ongoing pregnancy rate of 37.5% was achieved in the stimulated cycles. DISCUSSION: Although the current study found no early secretory transformation in stimulated endometria before hCG administration, the ER and PR expression in these endometria is similar to the one described during the first days of the luteal phase in natural cycles. Supraphysiological concentrations of estradiol and subtle progesterone rises in the late follicular phase might be responsible for this modulated steroid receptor profile. This phenomenon indicates accentuated maturation of the endometrium in IVF cycles from the pre-ovulatory phase onwards.     

The expression of the hormone receptors in the endometrium and endometrial polyps in postmenopausal women and its relationship to body mass index

OBJECTIVE: To evaluate and compare the relationship of body mass index (BMI) and the immunoexpression of estrogen (ER) and progesterone receptors (PR) in endometrial polyps (EP) and endometrium, in gland and stromal cells of postmenopausal women. METHODS: Thirty-five postmenopausal women with benign endometrial polyps, who had not been taking medication with hormonal effects for at least 6 months, were submitted to operative hysteroscopy. The presence of ER and PR were evaluated by immunohistochemical method using a semiquantitative analysis. RESULTS: BMI was significantly higher among patients with lower expression of ER in the glands of endometrium (p=0.02). EP and adjacent endometrium showed significantly higher proportion of positive cells in the glands than in the stroma, for both ER (p=0.0015 and 0.0018, respectively) and PR (p=0.0176 and p<0.0001, respectively). Glands and stroma cells showed significantly higher proportion of positive cells in polyps than in the endometrium, for ER (p<0.0001 and p=0.0034, respectively). CONCLUSIONS: The higher proportion of positive gland cells for ER in EP as compared to endometrium supports an implication of these receptors in the pathogenesis of polyps. Association of higher BMI with lower expression of ER in endometrial glands, but not in EP, may indicate that factors influencing ER expression do not affect EP, supporting an autonomous function of polyps.     

Immunohistochemical expression of Retinoblastoma gene product in normal,hyperplastic and malignant endometrium. Correlation with p53 protein expression,c-erbB-2, hormone receptors' status and proliferative activity

Alterations of the retinoblastoma (Rb) gene have been described in several human neoplasms and recently, it has been suggested that these alterations may play a role in the development of endometrial carcinomas. Paraffin sections from 31 cases of normal endometrium (16 proliferative, 15 secretory), 35 hyperplastic lesions and 89 endometrial carcinomas were investigated immunohistochemically for Rb protein (pRb) expression. The results were compared with p53 and c-erbB-2 protein expression, estrogen (ER) and progesterone (PR) receptors' status and with clinicopathological prognostic factors. pRb was expressed in normal, hyperplastic and neoplastic epithelium. Proliferative endometrium showed more intense and extensive pRb staining than secretory endometrium. pRb reactivity was heterogeneous in the hyperplastic endometrial cells. Lack or focal (< 10% of endometrial cells) pRb immunostaining was noted in 56.2% and 27% of carcinomas, respectively. In the remaining cases (16.8%) pRb staining was heterogeneous or diffuse. The absence or presence of pRb expression was independent of grade and stage. In normal proliferative and secretory endometrium, pRb expression was correlated with PR (p = 0.006 and p = 0.001, respectively), PCNA (p = 0.04 and p = 0.01, respectively) and MIB1 (p = 0.02 and p<0.0001, respectively) expression. In hyperplasias, pRb was related to PR (p = 0.016) and MIB1 (p < 0.0001) expression. In carcinomas, a relationship of pRb expression with p53 (p = 0.0015), ER (p = 0.0002), PR (p = 0.0004) and PCNA (p = 0.013) status was detected. We suggest that the absence or presence of pRb expression does not seem to be associated with the progression of endometrioid carcinoma. In addition, pRb seems to be normally regulated in relation to the proliferative growth fraction of the tumours.     

Expression of c-kit (CD117) in benign and malignant human endometrial epithelium

BACKGROUND: The proto-oncogene c-kit encodes a tyrosine kinase receptor (CD117) with a molecular weight of 145 kd. Previous studies, predominantly utilizing immunohistochemistry, have led to contradictory findings regarding the expression of CD117 in the endometrium. To help resolve this issue, we analyzed a series of benign and malignant endometrial tissues using both immunohistochemistry and Western blot analysis. OBJECTIVE: To examine the expression of CD117 in benign and malignant human endometrial tissues. METHODS: The expression of CD117 in 35 benign endometrial tissues (7 hyperplastic, 14 proliferative, 14 secretory) and 10 endometrioid carcinomas was investigated by immunohistochemistry (clone K45 monoclonal antibody). Immunoprecipitation (clone K69 monoclonal antibody) followed by Western blotting (clone K45 monoclonal antibody and clone 1.D9.3D6 monoclonal antibody) was performed to confirm CD117 expression. RESULTS: Fifty-seven percent of the hyperplasias, 93% of proliferative endometria, and 79% of secretory endometria immunostained positively for CD117. In benign endometria, epithelial staining tended to be more intense in the hyperplastic and proliferative endometria as compared to the secretory endometria, whereas endometrial stromal cells were not immunoreactive. Of the 10 frozen endometrial tissues analyzed by immunohistochemistry, 4 of 9 endometrioid carcinomas and a single case of an endometrioid polyp developing in association with a carcinoma expressed CD117. Immunoprecipitation followed by Western blot analysis confirmed expression of full-length CD117 in an endometrial polyp and carcinoma, and revealed a correlation between levels of immunoprecipitated CD117 and immunohistochemical staining intensity. CONCLUSIONS: Benign and malignant endometrial tissues express CD117. Our data suggest (a) a possible relationship between estrogen and CD117 expression in benign endometrium and (b) potential involvement of this growth factor receptor in endometrial carcinogenesis.     

Progesterone receptor distribution in the human endometrium. Analysis using monoclonal antibodies to the human progesterone receptor.

Two monoclonal antibodies to the human progesterone receptor (PR), JZB39 and KD68, were used in determining the immunohistochemical distribution of PR in the human endometrium throughout the menstrual cycle and after menopause. These antibodies recognized PR, as demonstrated by a downfield shift in the radiolabeled progestin binding peak when KD68 or JZB39 was added to high salt sucrose density gradients. The specificity of both antibodies for PR was confirmed with Western immunoblots and competition studies performed with purified receptor. Progesterone receptor was identified with these antibodies and the peroxidase-antiperoxidase technique in the nuclei of epithelial cells, stromal cells, and myometrial smooth muscle cells. The receptor content of endometrial epithelium and stroma varied with the menstrual cycle. The variation was most marked in the epithelium, which demonstrated very strong PR immunostaining during the proliferative phase and postovulation Days 1-3 of the early secretory phase, but PR immunostaining decreased sharply at postovulation Day 4 and remained relatively weak or absent during the mid and late secretory phase. In contrast, stromal cell nuclei were moderately to strongly immunostained even during the secretory phase. Progesterone receptor was not localized in vascular smooth muscle cells or endothelial cells. Specific cytoplasmic staining for PR was not identified in any of these cases, even prior to ovulation, when circulating levels of progesterone are low, indicating that both the steroid-occupied and -unoccupied forms of human progesterone receptor, like rabbit and guinea pig PR, and estrogen receptor, is a nuclear protein.     

Progesterone induces the fibulin-1 expression in human endometrial stromal cells

BACKGROUND: By using microarray analysis with human endometrial stromal cells (ESCs), we previously reported that the mRNA for fibulin-1, an extracellular matrix as well as a plasma glycoprotein, is up-regulated by progesterone. In the present study, we tried to clarify the spatial and temporal regulation mechanism of fibulin-1 in the human endometrium. METHODS AND RESULTS: Quantitative analysis with real-time PCR experiments on human endometrial tissues showed significantly higher fibulin-1 mRNA expressions in secretory phase endometria than in proliferative phase. Immunohistochemical studies revealed that the fibulin-1 protein is expressed in the glandular epithelium in proliferative phase endometria, and that expression switched to the stroma in secretory phase endometria. In culture experiments with ESCs, a significant increase of fibulin-1 mRNA expression was observed in cells treated with 6 alpha-methyl-17 alpha-hydroxy-progesterone acetate (MPA) or 8 bromoadenosine 3':5'-cyclic monophosphate (8-Br-cAMP). MPA stimulated the fibulin-1 mRNA expression in a dose-dependent manner, and a progesterone antagonist, RU-486, inhibited the stimulatory effect almost completely. By contrast, beta-estradiol alone did not increase the fibulin-1 mRNA expression. CONCLUSIONS: These results suggest that fiblin-1 is an important molecule that mediates progesterone action in human ESC differentiation towards implantation.     

P-glycoprotein expression is increased in human secretory and gestational endometrium.

To determine the expression, distribution, and intracellular localization of the multi-drug resistance gene product P-glycoprotein (Pgp) in the human menstrual cycle and in early gestational endometrium, we retrospectively studied 36 endometrial samples utilizing 3 murine monoclonal antibodies (MAbs), MAb C219, MAb C494, and MAb JSB-1, which recognize spatially distinct cytoplasmic epitopes of Pgp. Formalin-fixed, paraffin-embedded endometrial samples obtained from 36 women of reproductive age with normal menstrual cycles were assigned morphologic menstrual dates: proliferative (N = 10), secretory (N = 19), menstrual (N = 1), and gestational endometrium (N = 6). The cellular localization, staining intensity, and percentage of Pgp immunoreactive cells varied with the phase of the menstrual cycle. Early proliferative endometria revealed no Pgp immunoreactivity for all three MAbs. Mid-proliferative endometria showed weak immunostaining in less than 15% of the glandular epithelia. Late proliferative endometria showed a strong apical paranuclear/Golgi staining pattern. Early secretory endometria showed strong luminal membranous, subnuclear vacuolar membranous, and supranuclear vacuolar membranous immunostaining to all 3 MAbs in greater than 80% of the glandular epithelia. Apical paranuclear/Golgi and membranous staining were present in nonvacuolated mid-secretory glands. Immunoreactivity diminished in the late secretory phase with mild to moderate staining in less than 35% of the endometrial glands. Menstrual endometria showed weak, focal staining. All gestational endometria showed marked cytoplasmic, membranous, and apical/Golgi immunostaining both in the hypersecretory (Arias-Stella) endometrial glands as well as in the decidua. In general, the intensity of MAb C494 immunostaining was weaker than that of MAb C219 or JSB-1. These results suggest the following: Pgp expression parallels that of nuclear progesterone receptor expression in the normal human endometrial cycle and early gestational endometrium; Pgp expression corresponds to rising plasma and tissue levels of progesterone as well as to morphologic changes in the endometrial glandular epithelium associated with the marked development of the secretory apparatus; Pgp expression is hormonally regulated and may be involved in uteroplacental transport of substrates important in the implantation process and in early embryo-endometrial interactions; and Pgp may be involved in the transport of progesterone across the uterine epithelium during pregnancy.     

Steroid receptors in blood vessels of the rhesus macaque endometrium: a review

Estradiol (E) and progesterone (P) act on the primate endometrium to induce dramatic changes in the vascular system during the menstrual cycle. These changes include vessel breakdown and bleeding during menses, heightened angiogenesis during the early proliferative phase, and extensive growth of the spiral arteries in the luteal phase of the cycle. Because steroid hormone action is dependent upon the presence of specific nuclear receptors in target tissues, we used immunocytochemistry with receptor-specific monoclonal antibodies to characterize the spatial and temporal expression of estrogen receptor alpha (ERalpha), estrogen receptor beta (ERbeta), progesterone receptor PR and androgen (A) receptor (AR) in the endometrial vessels of rhesus macaques (Macaca mulatta). The only sex steroid receptor that was present in the endothelium and smooth muscle walls of endometrial vessels was ERbeta. ERalpha, PR, and AR were not detectable in either the endothelium or vascular smooth muscle cells of primate endometrial vessels. However, all of these receptors were strongly expressed by the perivascular stroma, and in these cells, all were modulated by the changes in levels of E and P during the cycle. We concluded that any direct effects of E on endometrial vessels would be mediated by ERbeta, and that the actions of P and A, and possibly some of E, were indirectly mediated through perivascular stromal cells.     

NEDD9在子宫内膜样腺癌中的表达及意义

目的 探讨NEDD9(neural precursor cell expressed developmentally down-regulated9)在子宫内膜样腺癌中的表达及意义。方法 应用免疫组化方法检测NEDD9在50例子宫内膜样腺癌和30例子宫内膜单纯性增生组织中的表达,并检测雌激素受体(ER)、孕激素受体(PR)在子宫内膜样腺癌的表达。结果 NEDD9在子宫内膜样腺癌中的表达高于在子宫内膜单纯性增生组织中的表达(p=0.226);在子宫内膜样腺癌中,NEDD9的高表达与肌层浸润≥1/2、FIGO分期III期和ER阴性表达相关(p=0.012,p=0.041及p=0.039)。结论 NEDD9促进子宫内膜样腺癌的侵袭,并与其ER表达状态负相关。     

Effects of progestins of human proliferative endometrium: an in vitro model of potential clinical relevance

Endometrium biopsy is a useful indicator of endometrium proliferation and is clinically relevant to diagnose cell proliferation and to evaluate response to progestin treatment and to monitor hormone replacement therapy. The aim of our study was to investigate the in vitro effects of progesterone and synthetic progestins on endometrium explants with a particular focus on estradiol receptor (ER) and progesterone receptor (PR) expression which reflects through cell secretion the hormone treatment efficiency. Most widely used progestagens belonging to three distinctive groups were investigated, i.e, medroxyprogesterone acetate (MPA), norethindrone acetate (NOR) and nomegestrol acetate (TX) which are respectively pregnane, 19-nortestosterone and norpregnane derivatives. We used organ culture from human proliferative endometrium, in which tissue integrity, particularly gland/stroma relationships are preserved. Progestins induce epithelial cell secretion and most effects were observed at the highest concentration tested (10(-7) M) and by TX and MPA on homogeneous and on heterogeneous (including also secretory glands) proliferative endometrium respectively. In these conditions, ER as well as PR expression were decreased on both glandular and stromal cells. In contrast, progesterone at 10(-7) M significantly decreased only PR, in glands and in stroma of homogeneous proliferative endometrium, and just in stroma of heterogeneous endometrium. NOR exhibited less effects. At lower concentrations (10(-8) M, 10(-9) M), significantly less effects were observed by synthetic progestins on proliferative endometrium. The experiments show that the different types of progestins do not exhibit in vitro similar effects. Since progestins variably act on proliferative endometrium, the exposure of endometrium explants to progestins may be a useful tool to predict clinical response to hormone therapy (individual "hormonogram") and to monitor endometrium proliferation.