Reduced expression of oestrogen receptor‐β is associated with tumour invasion and metastasis in oestrogen receptor‐α‐negative human papillary thyroid carcinoma

Oestrogens play an important role in the development and progression of papillary thyroid carcinoma (PTC) through oestrogen receptor (ER)‐α and ‐β, which may exert different or even opposing actions in PTC. The roles of ERβ in ERα‐negative PTC are still not clear. This study investigated the expression dynamics of ERβ1 (wild‐type ERβ) and its clinical significance in female ERα‐negative PTC patients. ERβ1 expression was detected in thyroid tissues of 136 female patients diagnosed with PTC. The relationships between ERβ1 expression and clinicopathological/biological factors were also analysed in female ERα‐negative PTC patients. The total score for ERβ1 was significantly lower in female ERα‐negative PTC patients with LNM or ETE when compared to those without LNM or ETE (Z = ?2.923, P = 0.003 and Z = ?3.441, P = 0.001). Accordingly, the total score for ERβ1 was significantly higher in ERα‐negative PTC patients expressing E‐cadherin compared to patients negative for E‐cadherin expression (Z = ?2.636, P = 0.008). The total score was lower in ERα‐negative PTC patients positive for VEGF expression compared to those negative for VEGF expression (Z = ?1.914, P = 0.056). This preliminary study indicates that reduced expression of ERβ1 in female ERα‐negative PTC patients is associated with greater progression of the disease. This may provide insights into the underlying molecular mechanisms of ERβ1 and could help design targeted approaches for treating or even preventing this disease.     

Evidence for cell-specific changes with age in expression of oestrogen receptor (ER) alpha and beta in bone fractures from men and women

Oestrogen is recognized as important for maintaining bone mass in men and women. Oestrogen receptor (ER) alpha and the recently described ER-beta are both expressed in bone cells, but have different affinities for oestrogen agonists and plant oestrogens, which could be important in developing treatments for bone loss in both men and women. It is unclear, however, which isoform predominates in bone; cell type and age may influence their relative expression. The present study has compared ER-alpha and ER-beta expression in serial sections of human fracture callus from males (n = 19, age range 5-72 years) and females (n = 15, age range 3-86 years) by indirect immunoperoxidase. Fracture callus was used as it can be readily obtained from individuals over a wide age range and contains a variety of bone cells. Antibody specificity was confirmed by western blotting and comparison of immunoreactivity in sections of breast tumour and benign prostate hyperplasia. No gender difference in ER expression was found in bone from individuals less than 40 years old. Proliferative chondrocytes were positive for both isoforms, but few larger hypertrophic cells were immunoreactive. ER-alpha and ER-beta were co-expressed in osteoclasts, suggesting that oestrogen may act directly on these cells. Osteoblasts, osteocytes, and mesenchymal cells also expressed both isoforms. In women over 40 years of age, however, relatively fewer biopsies contained osteocytes positive for ER-alpha and ER-beta. Likewise, the proportions of osteoblasts and mesenchymal cells expressing ER-beta were reduced but ER-alpha remained unaffected. In contrast, in men over 40 years, only the proportion of biopsies containing ER-beta-positive mesenchymal cells was lower. In these older men and women, ER-alpha and ER-beta expression was retained by the small proliferative chondrocytes. These results demonstrate that gender, age, and cell type are important determinants of ER isoform expression in skeletal cells.     

The role of oestrogen and progesterone receptors in gigantomastia

IntroductionGigantomastia is a rare condition characterised by excessive breast growth. The pathophysiology of mammary enlargement varies depending on the type of gigantomastia: gestational, juvenile virginal, or idiopathic. The study aimed at examining the receptor status (oestrogen receptor α (ERα) and progesterone receptor (PR)) of breast tissue in adult women with juvenile or idiopathic gigantomastia.Material and methodsThe study involved 70 women who underwent breast reduction due to juvenile or idiopathic gigantomastia. Control breast specimens were obtained from 18 female cadavers. ERα and PR expressions were detected immunohistochemically in breast gland samples.ResultsCategorised and uncategorised ERα and PR expression did not differ between women with gigantomastia and control women. It was found that in both groups weak (0–30%) ERα and PR expression was the most common. Analysis of categorised data also did not reveal any significant correlations between ERα or PR and the women’s age: for the whole group: p = 0.795 (ERα), p = 0.207 (PR), for women with gigantomastia: p = 0.934 (ERα), p = 0.43 (PR), and for control women: p = 0.638 (ERα), p = 0.805 (PR).ConclusionsGigantomastia is not caused by increased expression of ERα and PR. Analysing abnormal sensitivity of these receptors to hormones may be crucial in establishing the increased risk of breast cancer in women with gigantomastia.     

Expression of oestrogen receptor-beta in apocrine carcinomas of the breast

AIMS: Apocrine carcinoma of the breast seldom expresses oestrogen receptors (ER) or progesterone receptors (PR), but frequently expresses androgen receptors (AR). Because of this unusual hormone receptor status, it has been suggested that oestrogens have a less important role in the pathogenesis of apocrine carcinoma. The ER status of apocrine carcinoma has been studied for one kind of ER, the classic receptor now named ER-alpha; however, the status of ER-beta, a secondary oestrogen receptor, has not been examined systematically in apocrine carcinoma. The aim was to study ER-beta status in apocrine carcinoma. METHODS AND RESULTS: The expression of ER-beta was examined immunohistochemically in 48 apocrine carcinomas and compared with clinicopathological factors and ER-alpha, PR and AR status. ER-beta positivity was observed in 35 cases (73%), regardless of any clinicopathological factors or the status of other receptors. The results of ER-beta mRNA analysis supported the immunohistochemical results. CONCLUSIONS: The significance of oestrogens in apocrine carcinoma should not be dismissed at present when the role of ER-beta remains to be determined. Studying the action of oestrogen or antioestrogen in apocrine carcinoma may reveal a role for ER-beta independent of ER-alpha and raise the potential of hormonal therapy for these tumours.     

Pregnancy: The effect of RU486 on progesterone and oestrogen receptor concentration in human decidua on early pregnancy

Concentrations of progesterone receptor (PR) and oestrogen receptor(ER) were measured by radioligand assay in decidual tissue ofwomen undergoing termination of early pregnancy (amenorrhoeaup to 49 days). Pregnancies were terminated by vacuum aspirationat 12 or 36 h after oral administration of placebo or antiprogestinRU486 in different doses. Treatment with RU486 decreased decidualPR content, the effect being observed at 12 h as well as at36 h after 600 mg RU486 and at 36 h after 3 x 25 mg RU486 givenat 12 h intervals. PR concentration 12 h after a single doseof 25 mg RU486 was not affected. ER content was unchanged at12 h after RU486 but increased 36 h after 600 mg and 3 x 25mg RU486. Our data suggest that apart from blocking progesteroneaction, RU486 may exert its abortifacient effect through decreasingthe PR concentration. The simultaneous decrease of PR concentrationand an increase of ER concentration changes the balance betweenthem in favour of ER, which might also play a role in the abortifacienteffect of RU486.     

Prepubertal exposure to bisphenol‐A induces ERα upregulation and hyperplasia in adult gerbil female prostate

Prostate physiology is highly dependent on oestrogenic and androgenic homeostasis. Interferences in this equilibrium, especially in early periods of life, may disrupt the prostate and increase the susceptibility to the development of diseases with ageing. Taking this into account, and considering the increase of environmental chemicals with endocrine‐disrupting potential such as bisphenol‐A (BPA), this study aimed to evaluate the prostates of adult female gerbils exposed to BPA and BPA plus testosterone from pubertal to adult periods. Morphological, stereological and chemical analyses revealed that long‐term BPA exposure, even in environmental dosages, increases the proliferative status of the prostate, increases the number of ERα‐positive stromal cells and elicits the development of prostatic hyperplasia in adult female gerbils. Moreover, we also observed that the association with testosterone did not increase the proliferative status of the gland, which shows that low levels of BPA are enough to cause an oestrogenic disruption of the prostate in young adults. This evidence suggests that this oestrogenic endocrine disruptor may increase the susceptibility to prostatic disorders with ageing.     

Hepatobiliary cystadenoma with mesenchymal stroma: expression of oestrogen receptors in formalin-fixed tissue

We report three cases of hepatobiliary cystadenoma with mesenchymal stroma in which oestrogen receptor immunostaining was carried out, after using a microwave method of antigen retrieval. In one of the tumours immunoreactivity for oestrogen receptors was demonstrated within the mesenchymal stromal cells. The presence of oestrogen receptors supports the theory that oestrogens act as tumour promoters and may explain the female predilection.     

IMMUNOHISTOCHEMICAL ASSAY FOR OESTROGEN RECEPTORS IN PARAFFIN WAX SECTIONS OF BREAST CARCINOMA USING A NEW MONOCLONAL ANTIBODY

The aim of this study was to evaluate the utility of a new monoclonal antibody (AER311) that targets the oestrogen receptor (ER) in an immunohistochemical assay (IHA) applied to breast cancers. Ninety-seven cases of invasive ductal carcinoma were studied by AER311-IHA using a pressure-cooking antigen retrieval technique applied to formaldehyde-fixed, paraffin-embedded tissue sections; immunostaining was assessed by semi-quantitative scoring ( H score). There was 80 per cent concordance between the ER status measured by dextran-coated charcoal (DCC) assay and AER311-IHA, with 63/97 (65 per cent) tumours positive and 15/97 (15 per cent) tumours negative by both assays. Of the 12 DCC-positive cases that were negative by AER311-IHA, 11 were borderline positive (3–8 fmol/mg). Similarly, six of seven DCC-negative cases that scored positive by AER311-IHA had only borderline positive H scores (<50). When AER311-IHA was compared with 1D5-IHA, there was good concordance in ER status (77 per cent) and a significant correlation ( r =0·7, P <0·001) between H scores. Nevertheless, the correlation between ER level determined by AER311-IHA and that measured by DCC ( r =0·53, P <0·001) was higher than that for 1D5-IHA ( r =0·32, P =0·002). AER311-IHA can therefore provide reliable information about the ER status of breast carcinoma on paraffin sections and is an acceptable alternative to other commercially available monoclonal antibodies.     

Endocrinology: Comparative immunohistochemical study of oestrogen and progesterone receptors in the Fallopian tube and uterus at different stages of the menstrual cycle and the menopause

Oestrogen and progesterone are known to require their correspondingsteroid receptors to manifest structural and functional effectsin the Fallopian tube, uterus and other target organs. Thisstudy compares cyclical variations of these receptors in theuterus and in different segments of the Fallopian tube in thesame subjects using an immunocyto-chemical technique. The resultsshow that in the Fallopian tube, isthmic and ampullary epithelialand stromal oestrogen receptors increased in the follicularphase to a peak at mid cycle and then declined in the late lutealphase. The intensity of immunostaining of oestrogen receptorswas less in the Fallopian tube than in endometrial glandularepithelium. The fimbrial end demonstrated an opposite patternof staining to other segments of the tube. Progesterone receptorimmuno-staining was more intense than that for oestrogen receptorsin the follicular phase, and, whereas it disappeared completelyfrom the endometrial glandular epithelium in the late lutealphase, positive staining was clearly visualized in the tubalepithelium and stroma and endometrial stroma at this stage ofthe menstrual cycle. These differences in the steroid receptorcontent may reflect the changing and different functional rolesof these regions and may have important implications on humanreproduction.     

Oestrogen receptor‐β1 but not oestrogen receptor‐βcx is of prognostic value in apocrine carcinoma of the breast

Apocrine carcinoma of the breast, which frequently expresses oestrogen receptor‐β (ER‐β) in the absence of ER‐α and only infrequently is treated endocrinologically, gives an opportunity to investigate the clinicopathological role of ER‐β in breast cancer independent of ER‐α expression or tamoxifen treatment. Several isotypes of ER‐β, ER‐β1–5 etc., have been identified thus far; however, the clinicopathological importance of each ER‐β isotype in breast cancer is still uncertain. Here we aimed to clarify the clinicopathological importance of ER‐β1 and ER‐βcx (ER‐β2) in apocrine carcinomas, immunohistochemically examining expressions of ER‐β1 and ER‐βcx in 47 apocrine carcinomas. Positivity for ER‐β1 and ER‐βcx was observed in 41 (87%) and 18 (38%) of 47 cases, respectively. ER‐β1 positivity was related to smaller tumor size (P=0.0359), lower histological grade (P=0.0322), and higher disease‐free survival (P<0.0001), whereas ER‐βcx status was related to none of these parameters. ER‐β1 positivity was also associated with favorable clinical outcome in 24 so‐called triple‐negative (ER‐α‐negative/PR‐negative/HER2‐negative) apocrine carcinomas. ER‐β1 itself, independent of ER‐α expression and tamoxifen treatment, seems to have a tumor‐suppressive effect, at least in apocrine carcinomas. Further study of ER‐β1 is desired to optimize breast cancer treatment.     

Immunolocalization of oestrogen and progesterone receptors in prostatic hyperplasia and carcinoma

Oestrogen receptors and progesterone receptors were immunolocalized in 19 patients with benign prostatic hyperplasia and in 26 patients with prostatic carcinoma. Immunohistochemistry was performed on tissue that had been fixed in 8% paraformaldehyde and then paraffin-embedded, using microwave irradiation for antigen retrieval. Oestrogen receptor expression was observed exclusively in the stromal cells of six out of 26 (23%) patients with prostatic carcinoma, but in none of the cells of patients with benign prostatic hyperplasia. Progesterone receptor expression was detected in 16 of 19 (84%) and 17 of 19 (89%) of the epithelial cells and stromal cells of patients with benign prostatic hyperplasia, respectively. In patients with prostatic carcinoma, progesterone receptor immunoreactivity was observed in 12 of 20 (46%) and 20 of 26 (77%) of the carcinoma and stromal cells of prostatic carcinoma, respectively. The ratio of epithelial cells with progesterone receptor immunoreactivity corresponded well with that of stromal cells with immunoreactivity in patients with benign prostatic hyperplasia. However, the ratio of stromal cells with progesterone receptor immunoreactivity was much higher than that in carcinoma cells in patients with prostatic carcinoma. Immunolocalization patterns or the ratio of the cells with progesterone receptor immunoreactivity did not significantly correlate with histological differentiation or patient's age in carcinoma cases. However, patients with advanced surgical stages of disease demonstrated a significantly smaller number of carcinoma and stromal cells with progesterone immunoreactivity in patients with prostatic carcinoma. These results suggest that oestrogens do not have a direct effect on the biological behaviour of benign prostatic hyperplasia and prostatic carcinoma, but that progesterone appears to play a role in the pathogenesis of benign prostatic hyperplasia and prostatic carcinoma.     

Expression and functional analysis of Bax inhibitor-1 in human breast cancer cells

Recently, deregulated expression of the anti-apoptotic protein Bax inhibitor-1 (BI-1) has been shown in several human cancers. In this report, we show that BI-1 is expressed at various levels in six different human breast cancer cell lines. In order to investigate the function of BI-1 in oestrogen-dependent MCF-7, T-47D and oestrogen-independent MDA-MB-231 breast cancer cells, the RNA interference technique was used to knock down BI-1 expression specifically. Suppression of BI-1 expression caused a significant increase in spontaneous apoptosis in MDA-MB-231 cells, whereas MCF-7 and T-47D cells remained almost unaffected. Furthermore, BI-1 expression analysis using a cancer profiling array showed up-regulation of BI-1 expression in cancer samples of breast, uterus and ovary, whereas down-regulated BI-1 expression was identified in stomach, colon, kidney, lung and rectal cancer. In addition, immunohistochemical studies using a BI-1-specific antibody on human breast cancer specimens also revealed that BI-1 is expressed in the majority of cases. Moreover, to analyse whether BI-1 expression is oestrogen receptor-dependent, tumour cells were treated with oestradiol, ICI and tamoxifen: this showed no significant changes in BI-1 expression. Taken together, our results demonstrate that BI-1 expression is differentially deregulated in different cancers and that BI-1 plays an important role in preventing certain breast cancer cells from undergoing apoptosis. Thus, the development of novel therapeutic strategies based on targeting BI-1 gene expression in breast cancer could be restricted to selected individual cancer types.     

Short‐term exposure to chrysin promotes proliferative responses in the ventral male prostate and female prostate of adult gerbils

Chrysin (5,7‐dihydroxyflavone) is a bioactive compound found in different fruits, vegetables, honey and propolis. This flavone has been suggested for the treatment of reproductive dysfunction, mainly because of its antioxidant and hormonal properties. However, the effects of this polyphenol on the prostate are still poorly understood. The purpose of this study was to evaluate the effects of short‐term chrysin exposure on the ventral male and female prostates of adult gerbils. To evaluate the androgenic potential of chrysin, gerbils were also exposed to testosterone. Male and female gerbils were exposed to chrysin (50 mg/kg/day, orally) or testosterone cypionate (1 mg/kg/week, subcutaneously) for 3, 7 and 21 days. Prostates were dissected for morphological, stereological and immunohistochemical analyses. Serum levels of testosterone and 17β‐estradiol were measured by ELISA. Serum testosterone levels were not increased by chrysin supplementation in males or females. However, only females treated with chrysin for 21 days showed an increase in estradiol levels. Increased androgen receptor immunoreactivity, higher proliferation rates and glandular hyperplasia were observed in male and female prostates for all chrysin treatment times. Additionally, increased oestrogen receptor alpha immunoreactivity was observed in all chrysin‐treated females. Although chrysin and testosterone promoted similar morphological changes in the gerbil prostate, chrysin supplementation was less deleterious to prostate health, since it resulted in lower incidence of hyperplasia and an absence of neoplastic foci.     

Uterine leiomyoma versus leiomyosarcoma: a new attempt at differential diagnosis based on their cellular characteristics

AIM: To differentiate uterine leiomyoma (LM) with 'pseudosarcomatous' features from leiomyosarcoma (LMS). We hypothesized that because pseudosarcomatous LM is only a benign variant of conventional LM, it may have some characteristics different from LMS. METHODS AND RESULTS: Fourteen uterine smooth muscle tumours, which had been diagnosed as LMS previously, were reviewed and divided into adverse outcome (true LMS; seven cases) and excellent outcome groups (presumed pseudosarcomatous LM; seven cases) based on their clinical course. The tumours of the adverse outcome group were composed of rather uniform long spindle cells similar to those of leiomyosarcoma arising from the soft tissue. All tumours in this group had coagulative necrosis and all but one case were diagnosed preoperatively as malignant. In contrast, the tumours of the excellent outcome group showed significant histological diversity both between tumours and also in the same tumour and areas indistinguishable from conventional LM were often seen. All the tumours of this group were diagnosed preoperatively as benign. Immunohistochemically, all tumours of the excellent outcome group expressed progesterone receptor, often intensely, and also frequently expressed oestrogen receptor. In contrast, all the tumours of the adverse outcome group lacked them completely. CONCLUSION: Pseudosarcomatous LM has characteristics useful for differentiating it from LMS, which are common in conventional LM.