Characterization of estrogen receptors alpha and beta in uterine leiomyoma cells

Elagolix Alone or With Add-Back Therapy in Women With Heavy Menstrual Bleeding and Uterine Leiomyomas: A Randomized Controlled Trial

OBJECTIVE

To evaluate elagolix, an oral gonadotropin-releasing hormone receptor antagonist, alone or with add-back therapy, in premenopausal women with heavy menstrual bleeding (greater than 80 mL per month) associated with uterine leiomyomas.

METHODS

This double-blind, randomized, placebo-controlled, parallel-group study evaluated efficacy and safety of elagolix in cohorts 1 (300 mg twice daily) and 2 (600 mg daily) with four arms per cohort: placebo, elagolix alone, elagolix with 0.5 mg estradiol/0.1 norethindrone acetate, and elagolix with 1.0 mg estradiol/0.5 mg norethindrone acetate. A sample size of 65 per group was planned to compare elagolix with add-back to placebo on the primary end point: the percentage of women who had less than 80 mL menstrual blood loss and 50% or greater reduction in menstrual blood loss from baseline to the last 28 days of treatment. Safety assessments included changes in bone mineral density.

RESULTS

From April 8, 2013, to December 8, 2015, 571 women were enrolled, 567 were randomized and treated (cohort 1=259; cohort 2=308), and 80% and 75% completed treatment, respectively. Participants had a mean±SD age of 43±5 years (cohort 2, 42±5 years), and 70% were black (cohort 2, 74%). Primary end point responder rates in cohort 1 (cohort 2) were 92% (90%) for elagolix alone, 85% (73%) for elagolix with 0.5 mg estradiol/0.1 mg norethindrone acetate, 79% (82%) for elagolix with 1.0 mg estradiol/0.5 mg norethindrone acetate, and 27% (32%) for placebo (all P<.001 vs placebo). Elagolix groups had significant decreases compared with placebo in lumbar spine bone mineral density, which was attenuated by adding 1.0 mg estradiol/0.5 mg norethindrone acetate.

CONCLUSION

Elagolix with and without add-back significantly reduced menstrual blood loss in women with uterine leiomyomas. Add-back therapy reduced hypoestrogenic effects on bone mineral density.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT01817530; EU Clinical Trial Register, 2013-000082-37.

LncRNA SRA1 may play a role in the uterine leiomyoma tumor growth regarding the MED12 mutation pattern

Background

Uterine leiomyomas (ULMs) are benign uterine tumors that are estrogen-dependent. Recent studies suggest that the abnormal expression of the steroid receptor RNA activator 1 (SRA1) long non-coding RNA (lncRNA) might participate in the mechanisms of tumorigenesis of some hormone-dependent tumors including breast cancer. SRA1 is known to enhance the transcriptional activity of steroid receptors and also promotes steroidogenesis. The level of steroid hormones, such as estrogen and the progesterone, and their receptors play an important role in the development and growth of leiomyoma. The aim of the present study was to determine the expression level of lncRNA SRA1 in ULM tissues considering the MED12 mutation pattern.

Methods

Mutation screening was performed for MED12 exons 1 and 2 and the intronic flanking regions using Sanger sequencing in 60 ULM tissues. Quantitative real-time polymerase chain reaction (qRT-PCRs) was performed in order to estimate the expression of lncRNA SRA1 in leiomyoma samples with and without MED12 gene mutations. The expression results were analyzed by using LinReg and REST software.

Results

Mutations were detected in exon 2 of the MED12 in 28 (46.67%) ULM samples; including, 21 (75%) missense mutations and 7 (25%) in-frame deletions. No mutation was detected in the MED12 exon 1. LncRNA SRA1 was over-expressed in ULM samples without MED12 mutation compared with ULM samples harboring MED12 mutation (Expression ratio=2.5, P-value=0.004).

Conclusion

Present results suggest that lncRNA SRA1 may explain the phenotypic difference observed in the tumor size of ULM samples considering MED12 mutation pattern. Therefore, it serves as a good therapeutic target and provides new insight into understanding the disease molecular mechanism.

Understanding Obesity as a Risk Factor for Uterine Tumors Using Drosophila

Multiple large-scale epidemiological studies have identified obesity as an important risk factor for a variety of human cancers, particularly cancers of the uterus, gallbladder, kidney, liver, colon, and ovary, but there is much uncertainty regarding how obesity increases the cancer risks. Given that obesity has been consistently identified as a major risk factor for uterine tumors, the most common malignancies of the female reproductive system, we use uterine tumors as a pathological context to survey the relevant literature and propose a novel hypothesis: chronic downregulation of the cyclin-dependent kinase 8 (CDK8) module, composed of CDK8 (or its paralog CDK19), Cyclin C, MED12 (or MED12L), and MED13 (or MED13L), by elevated insulin or insulin-like growth factor signaling in obese women may increase the chances to dysregulate the activities of transcription factors regulated by the CDK8 module, thereby increasing the risk of uterine tumors. Although we focus on endometrial cancer and uterine leiomyomas (or fibroids), two major forms of uterine tumors, our model may offer additional insights into how obesity increases the risk of other types of cancers and diseases. To illustrate the power of model organisms for studying human diseases, here we place more emphasis on the findings obtained from Drosophila melanogaster.

Inverse association between estrogen receptor-α DNA methylation and breast composition in adolescent Chilean girls

Background

Estrogen receptor-α (ER-α) is a transcriptional regulator, which mediates estrogen-dependent breast development, as well as breast tumorigenesis. The influence of epigenetic regulation of ER-α on adolescent breast composition has not been previously studied and could serve as a marker of pubertal health and susceptibility to breast cancer. We investigated the association between ER-α DNA methylation in leukocytes and breast composition in adolescent Chilean girls enrolled in the Growth and Obesity Cohort Study (GOCS) in Santiago, Chile. Breast composition (total breast volume (BV; cm³), fibroglandular volume (FGV; cm³), and percent fibroglandular volume (%FGV)) was measured at breast Tanner stage 4 (B4). ER-α promoter DNA methylation was assessed by pyrosequencing in blood samples collected at breast Tanner stages 2 (B2; n = 256) and B4 (n = 338).

Results

After adjusting for fat percentage at breast density measurement, ER-α methylation at B2, and cellular heterogeneity, we observed an inverse association between B4 average ER-α DNA methylation and BV and FGV. Geometric mean BV was 15% lower (95% CI: − 28%, − 1%) among girls in the highest quartile of B4 ER-α methylation (6.96–23.60%) relative to the lowest (0.78–3.37%). Similarly, FGV was 19% lower (95% CI: − 33%, − 2%) among girls in the highest quartile of B4 ER-α methylation relative to the lowest. The association between ER-α methylation and breast composition was not significantly modified by body fat percentage and was not influenced by pubertal timing.

Conclusions

These findings suggest that the methylation profile of ER-α may modulate adolescent response to estrogen and breast composition, which may influence breast cancer risk in adulthood.

Electronic supplementary material

The online version of this article (10.1186/s13148-018-0553-5) contains supplementary material, which is available to authorized users.

Assessment of oxidant-antioxidant status alterations with tumor biomarkers and reproductive system hormones in uterine MYOMAS

OBJECTIVES

Uterine myomas (UM) are responsible for significant morbidity and have adverse effects on quality of life in women. Reactive oxygen species (ROS) and antioxidant enzymes (AOE), as well as sex steroids play important roles in the reproductive physiology processes. Thus, we aimed to investigate the role of oxidant-antioxidant status in UM by measuring the AOE activities and lipid peroxidation (LPO) levels. This is the first study assessing these parameters together in UM based on also menopausal status and evaluating possible correlations between AOE activities, LPO markers, tumor biomarkers, female reproductive system hormone levels, comprehensively.

STUDY DESIGN

The study group consisted of patients who have undergone surgical resection with confirmed pathology of uterine myoma (UM, n = 25) and divided into subgroups; premenopausal (UM_pre) and postmenopausal (UM_post). Erythrocyte copper-zinc superoxide dismutase (Cu,Zn-SOD), catalase (CAT), glutathione peroxidase (GPx1) activities were measured along with plasma malondialdehyde (MDA) and urinary 8-epi-prostaglandin F2α (8-epi-PGF2α) levels in patients with UM. The obtained data were compared to the data of healthy individuals (C, n = 25) and its subgroups; premenopausal (C_pre) and postmenopausal (C_post).

RESULTS

All AOE activities were higher (∼40% for Cu,Zn-SOD, p = 0.003; ∼55% for CAT, p = 0.001; ∼15% for GPx1, p = 0.169) and the LPO levels were lower (∼60% for MDA, p = 0.011 and ∼45% for 8-epi-PGF2α, p = 0.055) in patients with UM vs control. Approximately similar alterations were observed in UM_pre vs C_pre and in UM_post vs C_post. A significant negative correlation between erythrocyte Cu,Zn-SOD activity and plasma MDA levels (r = -0.431, p = 0.005) was reported.

CONCLUSION

Decreased LPO levels might be the consequence of compensator high antioxidant enzyme activities against mild oxidative stress in the circulation of patients with UM. The marked negative correlation between erythrocyte Cu,Zn-SOD activity and plasma MDA levels also supported this finding.

Association of estrogen and progesterone receptor gene polymorphisms and their respective hormones in uterine leiomyomas

The steroid hormones estradiol and progesterone play an important role in the pathophysiology of fibroids that occurs in 20-25 % of women in the reproductive age. Our study examines the risk imposed by estrogen and progesterone plasma levels in correlation with the ERβ (-13950T/C) and PGR (+331G/A) receptor gene polymorphisms. The study population included 296 individuals (146 UL cases and 150 female controls). Hormonal levels were estimated by ELISA and genotyping was carried out by PCR-RFLP analysis, and the obtained results were statistically analyzed. Estrogen levels were found to be high in cases with the "TC" genotype of ERβ receptor polymorphism compared to controls, whereas individuals with "GA" and "AA" genotype of PGR receptor polymorphism showed high progesterone levels for cases when compared to controls. The TC genotype of the ERβ receptor polymorphism and the GA and AA genotypes of the PGR receptor polymorphism and their respective hormonal levels can be developed as markers in the prediction of uterine fibroids.

Estrogen receptors and human disease: an update

A myriad of physiological processes in mammals are influenced by estrogens and the estrogen receptors (ERs), ERα and ERβ. As we reviewed previously, given the widespread role for estrogen in normal human physiology, it is not surprising that estrogen is implicated in the development or progression of a number of diseases. In this review, we are giving a 5-year update of the literature regarding the influence of estrogens on a number of human cancers (breast, ovarian, colorectal, prostate, and endometrial), endometriosis, fibroids, and cardiovascular disease. A large number of sophisticated experimental studies have provided insights into human disease, but for this review, the literature citations were limited to articles published after our previous review (Deroo and Korach in J Clin Invest 116(3):561-570, 2006) and will focus in most cases on human data and clinical trials. We will describe the influence in which estrogen's action, through one of or both of the ERs, mediates the aforementioned human disease states.

Comparative analysis of the ERα/ERβ ratio and neurotensin and its high-affinity receptor in myometrium, uterine leiomyoma, atypical leiomyoma, and leiomyosarcoma

Deregulated steroids are involved in different hormone-dependent tumors, including benign and malignant uterine neoplasms. Leiomyomas (LM) are estrogen and progesterone-dependent benign tumors, whereas "bizarre or atypical LMs" (AL) are considered a subgroup of LM and clinically benign, although their malignant potential is suspect. Uterine leiomyosarcomas (LMS) are malignant smooth muscle tumors, and ovarian steroids may control their growth. Estrogen effects are mediated by 2 receptors, estrogen receptors (ER) α and β, and the ratio of both receptors seems to be a critical parameter in the estrogen-mediated carcinogenic process. Estradiol induces the expression of neurotensin (NTS), and the coupling of this peptide with its high-affinity receptor, NTS1, has been involved in the regulation of tumoral cell growth. Given the importance of these markers in tumor development, we aim to determine the status of ERα and ERβ in the myometrium and LM, AL, and LMS, concomitantly with the expression of NTS/NTS receptor 1 in these tumors. For that purpose, we use immunohistochemistry for all markers analyzed and in-situ hybridization to detect NTS mRNA. These data suggest that LMS are estrogen-dependent tumors, which may use NTS as an autocrine growth factor. In addition, the phenotype of AL with regard to ERα and ERβ status and NTS expression is closer to LMS than LM; thus, a potential malignization of this tumor is feasible.

Uterine myomas revisited

The present study was planned to review the pathophysiology of uterine myomas and emphasize the principles of logical management on the basis of literature review and synthesis of the author's experience. The growth of uterine myomas, the most common solid pelvic tumors in women, is related to genetic predisposition, hormonal influences and growth factors. The treatment options include pharmacologic, surgical and radiographic interventions. Most asymptomatic myomas can be followed serially for progressive growth or development of symptoms. The various diagnostic and therapeutic advancements available today permit higher management flexibility with safe options, which must be tailored to the individual patients requirement.

Estrogen receptor alpha and beta in uterine fibroids: a basis for altered estrogen responsiveness

OBJECTIVE

To investigate the relative expression and the DNA-binding status of estrogen receptors alpha and beta in fibroids and normal myometrial tissue to explore the molecular basis of altered estrogen responsiveness of leiomyomas.

DESIGN

Biopsy samples from uterine fibroids and adjacent normal myometrial tissue at the follicular phase of the menstrual cycle.

SETTING

Aretaieio University Hospital and the National Hellenic Research Foundation, Athens, Greece.

PATIENT(S)

Thirty-five patients who underwent hysterectomy or myomectomy because of myoma symptoms.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Deoxyribonucleic acid-binding status of estrogen receptors alpha and beta.

RESULT(S)

The level of messenger RNA expression of estrogen receptor alpha and beta and the level of estrogen receptor as a whole are increased on average to a similar extent in leiomyomas compared with normal myometrium. Occasionally, however, estrogen receptor alpha is disproportionately increased in leiomyomas, and this appears to increase the amount of estrogen receptor alpha that binds to the estrogen-responsive element of estrogen target genes as homodimer rather than as heterodimer with estrogen receptor beta.

CONCLUSION(S)

The estrogen receptor alpha-to-estrogen receptor beta expression ratio rather than the individual expression levels determines the fraction of DNA-binding homodimers of estrogen receptor alpha and possibly the growth potential of myomas.

Transcriptional analysis of steroid hormone receptors in smooth muscle uterine leiomyoma tumors of postmenopausal patients

Smooth muscle tumors are histologically separated into benign leiomyomas and malignant leiomyosarcomas. Uterine leiomyomas represent benign clonal tumors often arising within the smooth muscle tissue of the human uterus. Uterine leiomyomas develop after the start of the menstrual cycle, become symptomatic during middle age, and in most postmenopausal patients tumor regression occurs. Rarely, leiomyomas progress to leiomyosarcomas, where many sarcomas have markedly reduced or no steroid hormone receptors, thus, evolve to a hormone non-responsive state. Premenopausal leiomyomas are known to express higher levels of estrogen receptor-alpha (ERalpha), estrogen receptor-beta (ERbeta) and progesterone receptor (PGR) than control myometrium, whereas postmenopausal leiomyomas have not been so well characterized molecularly. In this present investigation, ERbeta, ERalpha and PGR gene expression were assessed in leiomyomas and in matched adjacent myometrium from a cohort of 14 postmenopausal patients using semi-quantitative Realtime PCR and RT-PCR. The mean average results showed that ERbeta was 2.5-fold statistically significantly over expressed in postmenopausal leiomyomas compared to patient matched myometrium (p=0.038), whereas ERalpha and PGR were not significantly differently expressed. These results showed that up-regulation of ERbeta occurred at the transcriptional level in postmenopausal leiomyomas. Quantitation of steroid hormone receptors from benign uterine tumors may be important for a more tailored therapy. In addition, a role for steroid hormones, specifically ERbeta, is discussed in terms of benign tumor regression or tumor maintenance in postmenopausal leiomyomas.

Distribution patterns of estrogen receptor alpha and beta in the human cortex and hippocampus during development and adulthood

The expression of estrogen receptors (ERs) in the developing and adult human brain has not been clearly established, although estrogens are crucial for neuronal differentiation, synapse formation, and cognitive functions. By using immunohistochemistry, we have studied the distribution of ER alpha and ER beta in human cerebral cortex and hippocampus from early prenatal stages to adult life. ER alpha was detected in the cortex at 9 gestational weeks (GW), with a high expression in proliferating zones and the cortical plate. The staining intensity decreased gradually during prenatal development but increased again from birth to adulthood. In contrast, ER beta was first detected at 15 GW in proliferating zones, and at 16/17 GW, numerous ER beta immunopositive cells were also observed in the cortical plate. ER beta expression persisted in the adult cortex, being widely distributed throughout cortical layers II-VI. In addition, from around 15 GW to adulthood, ER alpha and ER beta were expressed in human hippocampus mainly in pyramidal cells of Ammon's horn and in the dentate gyrus. Western blotting and immunohistochemistry in the adult cerebral cortex and hippocampus revealed lower protein expression of ER alpha compared with ER beta. Double immunostaining showed that during fetal life both ERs are expressed in neurons as well as in radial glia, although only ER alpha is expressed in the Cajal-Retzius neurons of the marginal zone. These observations demonstrate that the expression of ER alpha and ER beta displays different spatial-temporal patterns during human cortical and hippocampal development and suggest that both ERs may play distinct roles in several processes related to prenatal brain development.