Ovarian steroids, stem cells and uterine leiomyoma: therapeutic implications

Analysis of Expression of the ANG1, CaSR and FAK Proteins in Uterine Fibroids

Understanding the molecular factors involved in the development of uterine myomas may result in the use of pharmacological drugs instead of aggressive surgical treatment. ANG1, CaSR, and FAK were examined in myoma and peripheral tissue samples taken from women after myoma surgery and in normal uterine muscle tissue samples taken from the control group. Tests were performed using tissue microarray immunohistochemistry. No statistically significant differences in ANG1 expression between the tissue of the myoma, the periphery, and the normal uterine muscle tissue of the control group were recorded. The CaSR value was reduced in the myoma and peripheral tissue and normal in the group of women without myomas. FAK expression was also lower in the myoma and periphery compared to the healthy uterine myometrium. Calcium supplementation could have an effect on stopping the growth of myomas.

Roles of estrogen and its receptors in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is an endocrine disorder characterized by abnormal steroid hormone levels in peripheral blood and poor-quality oocytes. In the ovary, androgen is produced by theca cells, and estrogen is produced by granulosa cells. Androgen is converted to estrogen in granulosa cells, with cytochrome P450 aromatase as the limiting enzyme during this process. Estrogen receptors (ER) include ER alpha, ER beta, and membrane receptor GPR30. Studies have demonstrated that the abnormal functions of estrogen and its receptors and estradiol synthesis-related enzymes are closely related to PCOS. In recent years, some estrogen-related drugs have made significant progress in clinical application for subfertility with PCOS, such as letrozole and clomiphene. This article will elaborate on the recent advances in PCOS caused by abnormal expression of estrogen and its receptors and the application of related targeted small molecule drugs in clinical research and treatment.

Psychological distress and uterine fibroids: a bidirectional two-sample mendelian randomization study

BACKGROUND

Observational data indicates a connection between emotional discomfort, such as anxiety and depression, and uterine fibroids (UFs). However, additional investigation is required to establish the causal relationship between them. Hence, we assessed the reciprocal causality between four psychological disorders and UFs utilizing two-sample Mendelian randomization (MR).

METHODS

To evaluate the causal relationship between four types of psychological distress (depressive symptoms, severe depression, anxiety or panic attacks, mood swings) and UFs, bidirectional two-sample MR was employed, utilizing single nucleotide polymorphisms (SNPs) associated with these conditions. Both univariate MR (UVMR) and multivariate MR (MVMR) primarily applied inverse variance weighted (IVW) as the method for estimating potential causal effects. Complementary approaches such as MR Egger, weighted median, simple mode, and weighted mode were utilized to validate the findings. To assess the robustness of our MR results, we conducted sensitivity analyses using Cochran's Q-test and the MR Egger intercept test.

RESULTS

The results of our UVMR analysis suggest that genetic predispositions to depressive symptoms (Odds Ratio [OR] = 1.563, 95% Confidence Interval [CI] = 1.209-2.021, P = 0.001) and major depressive disorder (MDD) (OR = 1.176, 95% CI = 1.044-1.324, P = 0.007) are associated with an increased risk of UFs. Moreover, the IVW model showed a nominally significant positive correlation between mood swings (OR: 1.578; 95% CI: 1.062-2.345; P = 0.024) and UFs risk. However, our analysis did not establish a causal relationship between UFs and the four types of psychological distress. Even after adjusting for confounders like body mass index (BMI), smoking, alcohol consumption, and number of live births in the MVMR, the causal link between MDD and UFs remained significant (OR = 1.217, 95% CI = 1.039-1.425, P = 0.015).

CONCLUSIONS

Our study presents evidence supporting the causal relationship between genetic susceptibility to MDD and the incidence of UFs. These findings highlight the significance of addressing psychological health issues, particularly depression, in both the prevention and treatment of UFs.

Uterine Fibroids

This JAMA Insights in the Women’s Health series discusses the incidence, diagnosis, and treatment of uterine fibroids.

Causal relationship between female reproductive factors, sex hormones and uterine leiomyoma: a Mendelian randomization study

RESEARCH QUESTION

Are the observed associations between female reproductive factors and sex hormones with the risk of uterine leiomyoma truly causal associations?

DESIGN

The putative causal relationships between female reproductive factors and sex hormones with uterine leiomyoma were investigated using two-sample Mendelian randomization. Statistics on exposure-associated genetic variants were obtained from genome-wide association studies (GWAS). The uterine leiomyoma GWAS from the FinnGen and FibroGENE consortia were used as outcome data for discovery and replication analyses, respectively. Results were pooled by meta-analysis. Sensitivity analyses ensured robustness of the Mendelian randomization analysis.

RESULTS

When FinnGen GWAS were used as outcome data, a causal relationship was found between age at menarche (OR 0.84, P < 0.0001), age at menopause (OR 1.08, P < 0.0001), number of live births (OR 0.25, P < 0.001) and total testosterone levels (OR 0.90, P < 0.001) with the risk of uterine leiomyoma. When FibroGENE GWAS were used as outcome data, Mendelian randomization results for age at menopause, the number of live births and total testosterone levels were replicated. In the meta-analysis, a later age at menopause (OR 1.08, P < 0.0001) was associated with an increased risk of uterine leiomyoma. A higher number of live births (OR 0.25, P < 0.0001) and higher total testosterone levels (OR 0.90, P < 0.0001) were associated with a decreased risk of uterine leiomyoma.

CONCLUSIONS

A causal relationship between later age at menopause, lower number of live births and lower total testosterone levels with increased risk of uterine leiomyoma was found.

Current and Emerging Treatment Options for Uterine Fibroids

Uterine fibroids are the most common benign neoplasm of the female reproductive tract in reproductive age women. Their prevalence is age dependent and can be detected in up to 80% of women by the age of 50 years. Patients affected by uterine fibroids may experience a significant physical, emotional, social, and financial toll as well as losses in their quality of life. Unfortunately, curative hysterectomy abolishes future pregnancy potential, while uterine-sparing surgical and radiologic alternatives are variously associated with reduced long-term reproductive function and/or high tumor recurrence rates. Recently, pharmacological treatment against uterine fibroids have been widely considered by patients to limit uterine fibroid-associated symptoms such as heavy menstrual bleeding. This hormonal therapy seemed effective through blocking the stimulatory effects of gonadal steroid hormones on uterine fibroid growth. However, they are contraindicated in women actively pursuing pregnancy and otherwise effective only during use, which is limited because of long-term safety and other concerns. Accordingly, there is an urgent unmet need for safe, durable, and fertility-compatible non-surgical treatment options for uterine fibroids. In this review article, we cover the current pharmacological treatments for uterine fibroids including their comparable efficacy and side effects as well as emerging safe natural compounds with promising anti-uterine fibroid effects.

Dysbiosis of vaginal and cervical microbiome is associated with uterine fibroids

Dysbiosis of the female reproductive tract is closely associated with gynecologic diseases. Here, we aim to explore the association between dysbiosis in the genital tract and uterine fibroids (UFs) to further provide new insights into UF etiology. We present an observational study to profile vaginal and cervical microbiome from 29 women with UFs and 38 healthy women, and 125 samples were obtained and sequenced. By comparing the microbial profiles between different parts of the reproductive tract, there is no significant difference in microbial diversity between healthy subjects and UF patients. However, alpha diversity of UF patients was negatively correlated with the number of fibroids. Increased Firmicutes were observed in both the cervical and vaginal microbiome of UF patients at the phylum level. In differential analysis of relative abundance, some genera were shown to be significantly enriched (e.g., Erysipelatoclostridium, Mucispirillum, and Finegoldia) and depleted (e.g., Erysipelotrichaceae UCG-003 and Sporolactobacillus) in UF patients. Furthermore, the microbial co-occurrence networks of UF patients showed lower connectivity and complexity, suggesting reduced interactions and stability of the cervical and vaginal microbiota in UF patients. In summary, our findings revealed the perturbation of microbiome in the presence of UFs and a distinct pattern of characteristic vaginal and cervical microbiome involved in UFs, offering new options to further improve prevention and management strategies.

Genetic liability to multiple factors and uterine leiomyoma risk: a Mendelian randomization study

Background and objective

Uterine leiomyoma is the most common benign tumor in females of reproductive age. However, its causes have never been fully understood. The objective of our study was to analyze the causal association between various factors and uterine leiomyoma using Mendelian randomization (MR).

Methods

Genetic variables associated with risk factors were obtained from genome-wide association studies. Summary-level statistical data for uterine leiomyoma were obtained from FinnGen and the UK Biobank (UKB) consortium. We used inverse variance weighted, MR-Egger, and weighted median methods in univariate analysis. Multivariable MR analysis was used to identify independent risk factors. A fixed-effect model meta-analysis was used to combine the results of the FinnGen and UKB data.

Results

In the FinnGen data, higher genetically predicted age at natural menopause, systolic blood pressure (SBP), diastolic blood pressure (DBP), and fasting insulin were associated with an increased risk of uterine leiomyoma, while higher age at menarche was associated with a reduced risk of uterine leiomyoma. Multivariable MR analysis of SBP and DBP showed that higher DBP might be an independent risk factor of uterine leiomyoma. In the UKB data, the results for age at natural menopause, SBP, DBP, and age at menarche were replicated. The result of the meta-analysis suggested that uterine leiomyoma could also be affected by polycystic ovary syndrome (PCOS), endometriosis, and 2-hour glucose level.

Conclusion

Our MR study confirmed that earlier menstrual age, hypertension, obesity, and elevated 2-hour glucose post-challenge were risk factors for uterine leiomyoma, and the causal relationship between smoking and uterine leiomyoma was ruled out. In addition, later age of menopause and endometriosis were found to increase the risk of uterine leiomyoma, while PCOS was found to decrease the risk.

A View on Uterine Leiomyoma Genesis through the Prism of Genetic, Epigenetic and Cellular Heterogeneity

Uterine leiomyomas (ULs), frequent benign tumours of the female reproductive tract, are associated with a range of symptoms and significant morbidity. Despite extensive research, there is no consensus on essential points of UL initiation and development. The main reason for this is a pronounced inter- and intratumoral heterogeneity resulting from diverse and complicated mechanisms underlying UL pathobiology. In this review, we comprehensively analyse risk and protective factors for UL development, UL cellular composition, hormonal and paracrine signalling, epigenetic regulation and genetic abnormalities. We conclude the need to carefully update the concept of UL genesis in light of the current data. Staying within the framework of the existing hypotheses, we introduce a possible timeline for UL development and the associated key events—from potential prerequisites to the beginning of UL formation and the onset of driver and passenger changes.

Androgen Signaling in Uterine Diseases: New Insights and New Targets

Common uterine diseases include endometriosis, uterine fibroids, endometrial polyps, endometrial hyperplasia, endometrial cancer, and endometrial dysfunction causing infertility. Patients with uterine diseases often suffer from abdominal pain, menorrhagia, infertility and other symptoms, which seriously impair their health and disturb their lives. Androgens play important roles in the normal physiological functions of the uterus and pathological progress of uterine diseases. Androgens in women are synthesized in the ovaries and adrenal glands. The action of androgens in the uterus is mainly mediated by its ligand androgen receptor (AR) that regulates transcription of the target genes. However, much less is known about the signaling pathways through which androgen functions in uterine diseases, and contradictory findings have been reported. This review summarizes and discusses the progress of research on androgens and the involvement of AR in uterine diseases. Future studies should focus on developing new therapeutic strategies that precisely target specific AR and their related signaling pathways in uterine diseases.

Uterine tumor resembling ovarian sex cord tumor: A rare case report

RATIONALE

A uterine tumor resembling an ovarian sex cord tumor (UTROSCT) is a clinically rare disease with an unclear origin and biological behavior.

PATIENT CONCERNS

We present a case of UTROSCT in a 42-year-old woman who presented with abnormally increased menstrual volume for 2 years.

DIAGNOSES

Initially, only ultrasound examination was performed to diagnose uterine fibroids, and then the tumor was surgically removed and sent for pathological examination. The patient was ultimately diagnosed with UTROSCT mainly based on pathological immunohistochemical examination and was further diagnosed with low malignant potential for recurrence based on genetic testing.

INTERVENTIONS AND OUTCOMES

The patient underwent hysterectomy and bilateral adnexectomy, and no adjuvant radiotherapy or chemotherapy was performed after the surgery. Follow-up to date has indicated that she is in good condition.

LESSONS

UTROSCT is a rare disease that requires pathological immunohistochemical examination to confirm the diagnosis and genetic testing when necessary so that a clear diagnosis can inform better decision-making regarding treatment measures.

Immunohistochemical Expression of Vitamin D Receptor in Uterine Fibroids

One of the many factors involved in the development of uterine fibroids is vitamin D deficiency. One aspect of this deficiency is decreased serum concentration of calcidiol-25(OH)D, a metabolite of D3 vitamin. The active form of vitamin D3, which arises after numerous enzymatic reactions, is calcitriol-1,25(OH)2D3; this compound is transported to various body tissues. Vitamin D possesses extra-genomic effects due to its influence on various signaling pathways, i.e., through activating tyrosine kinases and by genomic effects via binding to a specific nuclear receptor, vitamin D receptor (VDR). The vitamin D/VDR complex regulates the expression of genes and is involved in the pathogenesis of fibroids. Numerous studies have shown that vitamin D supplementation reduces fibroid size. It has also been shown that the expression of VDR in myoma tissue is significantly lower than in the uterine muscle tissue at the tumor periphery. However, the expression of VDR in non-myoma uterine muscle has not previously been investigated. Our VDR expression studies were performed immunohistochemically with tissue microarrays (TMA) in three tissue groups: 98 uterine myoma tissues, 98 uterine tissues (tumor margin), and 12 tissues of normal uterine muscle (i.e., without fibroids). A statistical analysis showed significantly lower VDR expression in uterine muscle at the periphery of the fibroid than in healthy uterine muscle. Lower expression of VDR at the periphery of the myoma compared to that in normal uterine muscle may indicate potential for new myomas. This observation and the described reduction in the size of fibroids after vitamin D supplementation supports the hypothesis of causal development of uterine fibroids and may be useful for the prevention of re-development in the event of their excision from the uterus.

A mediator complex subunit 12 gain-of-function mutation induces partial leiomyoma cell properties in human uterine smooth muscle cells

OBJECTIVE

To clarify whether a mediator complex subunit 12 (MED12) gain-of-function mutation induces leiomyoma cell properties in human uterine smooth muscle cells (USMCs).

DESIGN

Experimental study.

SETTING

Academic research laboratory.

PATIENT(S)

Women undergoing hysterectomy for leiomyoma.

INTERVENTION(S)

CRISPR/Cas9-mediated genome editing to introduce an MED12 gain-of-function mutation (G44D) into human USMCs.

MAIN OUTCOME MEASURE(S)

Cell proliferation, collagen production, and in vivo tumorigenicity of USMCs with vs. without the MED12 mutation.

RESULT(S)

Uterine smooth muscle cells isolated from the uterine myometrium of a 44-year-old patient were subjected to lentiviral vector-mediated gene transduction of the fluorescent protein Venus, followed by long-term passage. Uterine smooth muscle cells with a normal female karyotype, high cell proliferative activity, and Venus expression, but without stem/progenitor cell populations, were obtained and designated as USMC44. Using CRISPR/Cas9-mediated genome editing, mtUSMC44 (MED12, 131G>A, p.G44D) and mock USMC44 without MED12 mutation (wtUSMC44) were established from USMC44. wtUSMC44 and mtUSMC44 showed similar cell proliferation activity, even in the presence of estradiol and progesterone (EP) together with transforming growth factor-beta 3 (TGFB3). In addition, wtUSMC44 and mtUSMC44 generated similar tiny smooth muscle-like tissue constructs when xenotransplanted beneath the kidney capsule in immunodeficient mice treated with EP alone or TGFB3. In contrast, mtUSMC44 produced more collagen type I than wtUSMC in vitro, and this production was likely enhanced by EP and TGFB3.

CONCLUSION(S)

The results suggest that the MED12 gain-of-function mutation is involved in collagen production. Although approximately 70% of leiomyomas have MED12 mutations, additional factors and/or events other than MED12 and/or myometrial stem/progenitor cells may be required for fully inducing leiomyoma cell properties, including transformation, in USMCs.

Genetic and Epidemiological Similarities, and Differences Between Postoperative Intraperitoneal Adhesion Development and Other Benign Fibro-proliferative Disorders

Intraperitoneal adhesions complicate over half of abdominal-pelvic surgeries with immediate, short, and long-term sequelae of major healthcare concern. The pathogenesis of adhesion development is similar to the pathogenesis of wound healing in all tissues, which if unchecked result in production of fibrotic conditions. Given the similarities, we explore the published literature to highlight the similarities in the pathogenesis of intra-abdominal adhesion development (IPAD) and other fibrotic diseases such as keloids, endometriosis, uterine fibroids, bronchopulmonary dysplasia, and pulmonary, intraperitoneal, and retroperitoneal fibrosis. Following a literature search using PubMed database for all relevant English language articles up to November 2020, we reviewed relevant articles addressing the genetic and epidemiological similarities and differences in the pathogenesis and pathobiology of fibrotic diseases. We found genetic and epidemiological similarities and differences between the pathobiology of postoperative IPAD and other diseases that involve altered fibroblast-derived cells. We also found several genes and single nucleotide polymorphisms that are up- or downregulated and whose products directly or indirectly increase the propensity for postoperative adhesion development and other fibrotic diseases. An understanding of the similarities in pathophysiology of adhesion development and other fibrotic diseases contributes to a greater understanding of IPAD and these disease processes. At a very fundamental level, blocking changes in the expression or function of genes necessary for the transformation of normal to altered fibroblasts may curtail adhesion formation and other fibrotic disease since this is a prerequisite for their development. Similarly, applying measures to induce apoptosis of altered fibroblast may do the same; however, apoptosis should be at a desired level to simultaneously ameliorate development of fibrotic diseases while allowing for normal healing. Scientists may use such information to develop pharmacologic interventions for those most at risk for developing these fibrotic conditions.

Combined Influence of Nutrient Supply Level and Tissue Mechanical Properties on Benign Tumor Growth as Revealed by Mathematical Modeling

A continuous mathematical model of non-invasive avascular tumor growth in tissue is presented. The model considers tissue as a biphasic material, comprised of a solid matrix and interstitial fluid. The convective motion of tissue elements happens due to the gradients of stress, which change as a result of tumor cells proliferation and death. The model accounts for glucose as the crucial nutrient, supplied from the normal tissue, and can reproduce both diffusion-limited and stress-limited tumor growth. Approximate tumor growth curves are obtained semi-analytically in the limit of infinite tissue hydraulic conductivity, which implies instantaneous equalization of arising stress gradients. These growth curves correspond well to the numerical solutions and represent classical sigmoidal curves with a short initial exponential phase, subsequent almost linear growth phase and a phase with growth deceleration, in which tumor tends to reach its maximum volume. The influence of two model parameters on tumor growth curves is investigated: tissue hydraulic conductivity, which links the values of stress gradient and convective velocity of tissue phases, and tumor nutrient supply level, which corresponds to different permeability and surface area density of capillaries in the normal tissue that surrounds the tumor. In particular, it is demonstrated, that sufficiently low tissue hydraulic conductivity (intrinsic, e.g., to tumors arising from connective tissue) and sufficiently high nutrient supply can lead to formation of giant benign tumors, reaching tens of centimeters in diameter, which are indeed observed clinically.

Uterine Fibroids: Assessing Unmet Needs from Bench to Bedside

Uterine fibroids (leiomyomas) are noncancerous growths that can have deleterious effects on the health and quality of life for millions of women. Attempts to better understand the factors that influence prevalence and disparities associated with fibroids have been made; however, significant knowledge gaps continue to persist, which hinder care for individuals living with fibroids. The Society for Women's Health Research convened an interdisciplinary Uterine Fibroids Working Group to review the current state of knowledge about uterine fibroids and recommend areas in which to prioritize efforts to address research gaps and improve diagnosis, treatment, and access to care for patients with this chronic disease. Throughout a 2-day roundtable meeting, participants discussed updates on key literature, research, clinical practice, and public health data on uterine fibroids. Overarching themes and recommendations were identified and determined by consensus agreement of the participants at the conclusion of the meeting. Systematic studies of the etiology and pathology of uterine fibroids are needed to address important knowledge gaps and unmet clinical needs regarding the multifaceted management of fibroids and their effects on overall health and quality of life. The Working Group recommends addressing key deficits within the spheres of research, clinical care, and federal policy. Immediate needs include increasing research investment, improving fibroid assessment using pelvic imaging, implementing longitudinal study designs, addressing factors that contribute to disease disparities (especially among women of color), developing fertility-friendly treatment options, expanding awareness and education beyond gynecologic specialists, and advancing personalized patient care through shared decision-making approaches.

Molecular and Cellular Insights into the Development of Uterine Fibroids

Uterine leiomyomas represent the most common benign gynecologic tumor. These hormone-dependent smooth-muscle formations occur with an estimated prevalence of ~70% among women of reproductive age and cause symptoms including pain, abnormal uterine bleeding, infertility, and recurrent abortion. Despite the prevalence and public health impact of uterine leiomyomas, available treatments remain limited. Among the potential causes of leiomyomas, early hormonal exposure during periods of development may result in developmental reprogramming via epigenetic changes that persist in adulthood, leading to disease onset or progression. Recent developments in unbiased high-throughput sequencing technology enable powerful approaches to detect driver mutations, yielding new insights into the genomic instability of leiomyomas. Current data also suggest that each leiomyoma originates from the clonal expansion of a single transformed somatic stem cell of the myometrium. In this review, we propose an integrated cellular and molecular view of the origins of leiomyomas, as well as paradigm-shifting studies that will lead to better understanding and the future development of non-surgical treatments for these highly frequent tumors.

Linzagolix: a new GnRH-antagonist under investigation for the treatment of endometriosis and uterine myomas

INTRODUCTION

Uterine myomas and endometriosis are benign hormone-dependent diseases affecting women of reproductive age. Substantial efforts have been made to develop innovative medical options for treating these gynecologic diseases. Elagolix and relugolix have been approved in some countries for treating endometriosis and myomas, respectively; however, linzagolix (OBE 2109, KLH 2109) is a new oral gonadotropin-releasing hormone (GnRH) antagonist in phase II-III trials. Treatment options for women with contraindications for hormonal therapies or who refuse particular options, are the driving force behind the development of new drugs in this area.

AREA COVERED

This drug evaluation highlights definitive and preliminary results from previous and ongoing studies of linzagolix for the treatment of endometriosis and myomas.

EXPERT OPINION

Linzagolix showed a dose-dependent and rapidly reversible action on the pituitary-gonadal axis. In a recent phase II trial (EDELWEISS), linzagolix significantly reduced pain related to endometriosis and improved quality of life at single daily doses of 75-200 mg. The preliminary results of international, double-blind phase III trials (PRIMROSE 1 and 2) reported its efficacy in treating heavy menstrual bleeding related to myomas with a good safety profile. Further studies will determine the necessity of add-back therapy during long-term use of linzagolix.

A prognostic index model for predicting long-term recurrence of uterine leiomyoma after myomectomy

Introduction

Uterine leiomyoma (UL) is a common benign pelvic tumor in women that has a high recurrence rate. Our aim is to propose a prognostic index (PI) model for predicting the long-term recurrence risk of uterine leiomyoma (UL).

Methods

A total of 725 women who underwent myomectomy were enrolled in this retrospective multicenter study. Patients were contacted for follow-up. A PI model was proposed based on the multivariate Cox regression analysis in the model group. The predictive value of this model was tested in both internal and external validation group.

Results

PI formula = 1.5(if 3–5 leiomyomas) or 2(if >5 leiomyomas)+1(if residue)+1(if not submucosal)+1(if combined endometriosis). The PI value was divided into low-risk, intermediate-risk, and high-risk group by cut-off values 1.25 and 3.75. In the model group, the high-risk group had a significantly 4.55 times greater recurrence risk of UL than that in the low-risk group [cumulative recurrence rate (CR): 82.1% vs 29.5%, HR = 4.55, 95% CI 2.821–7.339]; the intermediate-risk group had a significantly 2.81 times greater recurrence risk of UL than that in the low-risk group (CR: 62.3% vs 29.5%, HR = 2.81, 95% CI 2.035–3.878). The differences between any two risk groups were also significant (P< 0.05) in both internal and external validation groups.

Conclusion

The model was proved to be effective in predicting recurrence of UL after myomectomy.

Ameliorative Effects of Component Chinese Medicine From Curcumae Rhizoma and Sparganii Rhizoma, a Traditional Herb Pair, on Uterine Leiomyoma in a Rat Model

Uterine leiomyoma (UL), common benign tumors in women of child-bearing age, are believed to be caused mainly by Qi stagnation and blood stasis, according to a theory of traditional Chinese medicine. Curcumae Rhizoma and Sparganii Rhizoma (CRSR) is a classical herb pair that activates blood circulation to dissipate blood stasis. The purpose of this study was to explore the prevention and treatment effects of CRSR component compatibility on UL in rats. We randomly assigned adult female non-pregnant rats into three groups: a normal control (NC) group, a UL model group, and a CRSR treatment group. We administered to the UL and CRSR groups oral gavage diethylstilbestrol and injected them with progesterone (P) to establish UL for 5 weeks. The CRSR group received a CRSR medicinal solution after daily modeling. The uterus morphology of the UL group showed significantly more swelling than did that of the NC group, and we found no significant abnormalities in the morphology of the CRSR group. The pathological changes associated with UL were relieved in the CRSR group. CRSR improved the related parameters of the uterus and ovarian coefficients, significantly reducing the concentrations of P in the serum and the concentrations of estradiol, P, estrogen receptor, and P receptor in the uterus and ovary. In addition, CRSR significantly improved the abnormal blood conditions of UL, shown by decreases in plasma viscosity, the erythrocyte sedimentation rate equation K value, and erythrocyte aggregation index. Therefore, CRSR component compatibility may prevent and cure UL through the above ways.

The influence of phenolic environmental estrogen on the transcriptome of uterine leiomyoma cells: A whole transcriptome profiling-based analysis

OBJECTIVE

The study aimed to recognize potential molecular targets and signal pathways whereby phenolic environmental estrogen promotes the proliferation of uterine leiomyoma cells.

METHODS

Primary cultured cell lines of uterine leiomyoma were treated with 0.1% DMSO, 10.0μmol/L Bisphenol A (BPA), and 32.0μmol/L Nonylphenol (NP) for 48 h before RNA-seq was performed. Those genes affected by BPA and NP were identified. Then, Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, and Protein-protein Interaction (PPI) analysis were performed. Quantitative real-time polymerase chain reaction (q-PCR) and western blot were used to verify the differentially expressed gene and protein.

RESULTS

Compared to with the control group, 739 differentially expressed genes were identified in both the BPA group and the NP group. GO enrichment analysis showed that the most enriched GO terms were connective tissue development and G1/S transition of mitotic cell cycle, and extracellular matrix. The results of KEGG enrichment analysis showed that differentially expressed mRNA were enriched mainly in three primary pathways, including environmental information processing, human diseases, and cellular processes. The cell cycle, PI3K-Akt signaling pathway are significantly enriched. The q-PCR and western blot verified the cell cycle associated genes and proteins were upregulated in both BPA group and NP group. Both BPA and NP activated the PI3K-AKT signaling pathway.

CONCLUSION

Phenolic environmental estrogens may promote the proliferation and cell cycle progression of uterine leiomyoma cells through rapid non-genomic ER signaling, which leads to disordered cell cycle regulation and accelerates the transition of the cell cycle from G0/G1 phase to S phase. In addition, as an external stimulant, phenolic estrogen promotes the upregulation of inflammatory factors in uterine leiomyomas.

Inhibition of Fibroblast Activation in Uterine Leiomyoma by Components of Rhizoma Curcumae and Rhizoma Sparganii

Background: The herbs Rhizoma Curcumae and Rhizoma Sparganii (RCRS) are often used in traditional Chinese medicine for the treatment of uterine leiomyoma (UL). The effectiveness of RCRS for the treatment of UL has been confirmed in our previous studies.

Purpose: This study aimed to investigate the molecular mechanism by which RCRS inhibits the activation of fibroblast activation protein (FAP) and prevents UL in rats.

Study Design and Methods: A Sprague Dawley (SD) rat model of UL was established via estrogen and progesterone load combined with external stimulation. Histological analyses, enzyme-linked immunosorbent assays, and western blotting were performed to evaluate the effect of RCRS on UL and elucidate its mechanism of action.

Results: Our data showed that the treatment of SD rats with RCRS significantly reduced the expression of extracellular matrix component collagen, FAP, and transforming growth factor beta (a FAP-activating factor) and the phosphorylation of the cell proliferation pathway-related signaling factors AKT/MEK/ERK.

Conclusion: Our results suggest that RCRS is effective in the prevention and treatment of UL in rats, and RCRS may exert its functions by inhibiting the activation of tumor-associated fibroblasts and cell proliferation and by improving the tumor extracellular matrix.

Massive Leiomyomata and Severe Endometriosis Resulting in a Frozen Pelvis in an Asymptomatic Patient

Leiomyomas, also known as uterine fibroids, are the most common benign uterine tumors in women. The most frequently reported symptoms are uterine bleeding and abdominal and/or pelvic pressure; however, most cases are asymptomatic and may be found incidentally. Endometriosis is a condition where the endometrium proliferates outside of the uterine cavity. Extrauterine endometrial implants are usually found in the ovaries, pelvis, and peritoneum, but can extend anywhere throughout the body. Women with endometriosis may exhibit dysmenorrhea, dyspareunia, dyschezia, and infertility. Inflammation caused by endometriosis may lead to fibrosis, scarring, and adhesions. We report a case of an asymptomatic 36-year-old African-American woman with increasing abdominal girth, consistent with a 28-week gestation, presenting to her obstetrician/gynecologist for her annual exam, who on further investigation is found to have multiple large fibroids, bilateral ovarian cysts, and widespread endometriosis with several adhesions ultimately leading to a frozen pelvis.

Uterine Fibroids and Progestogen Treatment: Lack of Evidence of Its Efficacy: A Review

BACKGROUND

The objective of this review is to determine the evidence or, conversely, the absence of evidence regarding the effectiveness of progestogens in treating premenopausal women with uterine fibroids. In particular, the goal is to address recurring questions as to whether they are effective or not for managing symptoms commonly attributed to fibroids.

METHODS

A review of the most relevant papers (n = 63) on the efficacy of progesterone and progestogens as medical therapy for uterine fibroids.

RESULTS

Having reviewed the most significant papers on the relationship between uterine fibroids and progesterone/progestogens, it is clear that there is biochemical, histological and clinical evidence that progesterone and progestogens play a critical role in the pathogenesis of myomas.

CONCLUSION

Since progesterone is already implicated in the pathogenesis of this entity, using progestogens to manage fibroids is like constantly adding fuel to the fire, rendering this treatment ineffective.

Uterine Stem Cells and Benign Gynecological Disorders: Role in Pathobiology and Therapeutic Implications

Stem cells in the endometrium and myometrium possess an immense regenerative potential which is necessary to maintain the menstrual cycle and support pregnancy. These cells, as well as bone marrow stem cells, have also been implicated in the development of common benign gynecological disorders including leiomyomas, endometriosis and adenomyosis. Current evidence suggests the conversion of uterine stem cells to tumor initiating stem cells in leiomyomas, endometriosis stem cells, and adenomyosis stem cells, acquiring genetic and epigenetic alterations for the progression of each benign condition. In this comprehensive review, we aim to summarize the progress that has been made to characterize the involvement of stem cells in the pathogenesis of benign gynecologic conditions which, despite their enormous burden, are not yet fully understood. We focus on the stem cell characteristics and aberrations that contribute to the development of benign gynecological disorders and the possible clinical implications of what is known so far. Lastly, we discuss the role of uterine stem cells in the setting of regenerative medicine, particularly in the treatment of Asherman syndrome.Graphical abstract.

Discovery and Characterization of BAY 1214784, an Orally Available Spiroindoline Derivative Acting as a Potent and Selective Antagonist of the Human Gonadotropin-Releasing Hormone Receptor as Proven in a First-In-Human Study in Postmenopausal Women

The growth of uterine fibroids is sex hormone-dependent and commonly associated with highly incapacitating symptoms. Most treatment options consist of the control of these hormonal effects, ultimately blocking proliferative estrogen signaling (i.e., oral contraceptives/antagonization of human gonadotropin-releasing hormone receptor [hGnRH-R] activity). Full hGnRH-R blockade, however, results in menopausal symptoms and affects bone mineralization, thus limiting treatment duration or demanding estrogen add-back approaches. To overcome such issues, we aimed to identify novel, small-molecule hGnRH-R antagonists. This led to the discovery of compound BAY 1214784, an orally available, potent, and selective hGnRH-R antagonist. Altering the geminal dimethylindoline core of the initial hit compound to a spiroindoline system significantly improved GnRH-R antagonist potencies across several species, mandatory for a successful compound optimization in vivo. In a first-in-human study in postmenopausal women, once daily treatment with BAY 1214784 effectively lowered plasma luteinizing hormone levels by up to 49%, at the same time being associated with low pharmacokinetic variability and good tolerability.

Association between obesity and the risk of uterine fibroids: a systematic review and meta-analysis

BACKGROUND

Uterine fibroids (UFs) are the most common form of sex steroid hormone-dependent benign tumours that grow in the walls of the uterus. Several observational studies have examined the association between obesity and the risk of UFs, but findings are inconsistent. The objective of this systematic review and meta-analysis is to further examine the association of obesity with the risk/prevalence of UFs.

METHODS

A literature search was performed in three databases (PubMed, EMBASE and Web of Science) from 1 January 1992 to 30 May 2020. We used random-effect models to calculate the pooled ORs with corresponding 95% CIs. Additionally, we performed a dose-response meta-analysis to analyse the effect of body mass index (BMI), weight change since age 18, waist-to-hip ratio and waist circumference on the risk/prevalence of UFs.

RESULTS

A total of 22 articles, covering 24 studies including 325 899 participants and 19 593 cases, were selected based on our inclusion criteria. We found a positive association between obesity and the risk/prevalence of UFs (OR, 1.19; 95% CI, 1.09 to 1.29). Among participants with the highest BMI, the pooled OR was 1.19 (1.09 to 1.31) when compared to participants with normal BMI. For weight change since age 18, the pooled OR (95% CI) of UFs was 1.26 (1.12 to 1.42) among the highest change group when compared with no change. Additionally, our meta-analysis indicated the relationship of BMI with risk of UFs to be an inverse J-shaped pattern.

CONCLUSIONS

The results of this meta-analysis suggest that obesity may increase the risk/prevalence of UFs, and the association is non-linear.

Increased Association between Previous Pregnancies and Use of Chemical Relaxers in 74 Women with Central Centrifugal Cicatricial Alopecia

Background:

Central centrifugal cicatricial alopecia (CCCA) is a type of scarring alopecia exclusively seen in women of African descent. The etiology is unknown and epidemiologic studies including data on comorbidities in patients with CCCA are limited. Our primary objective was to identify possible etiologic and lifestyle associations in patients with CCCA.

Materials and Methods:

A retrospective chart review was conducted for patients diagnosed with CCCA between January 1, 2013, and January 1, 2018, at a university dermatology outpatient clinic. Controls consisted of age-, sex-, and race-matched African–American women diagnosed with other hair loss conditions. Data from 74 cases and 96 controls were collected and analyzed via logistic regression. In addition, a phone survey was conducted in the CCCA cohort asking specific questions related to their condition and quality of life.

Results:

A significant relationship was found between CCCA and previous pregnancies as well as the use of chemical relaxers: patients with CCCA were 11.71 times more likely to have had a previous pregnancy (P < 0.001) and 12.37 times more likely to have used chemical relaxers in the past (P < 0.001). Association with uterine fibroids was found not statistically significant (P > 0.05).

Conclusion:

We identified an association between previous pregnancies and use of chemical relaxers in patients diagnosed with CCCA when compared to controls. These findings may help to plan prospective studies aiming at establishing a more concrete link between hormones and CCCA.

Steroid hormones and hormone antagonists regulate the neural marker neurotrimin in uterine leiomyoma

OBJECTIVE

To characterize the role of steroid hormone and antihormone exposure on neurotrimin (NTM) expression in human leiomyoma and myometrial tissue and cells.

DESIGN

Laboratory study of placebo and ulipristal acetate (UPA)-treated patient tissue. In vitro assessment of immortalized myometrial and leiomyoma cell lines after hormone and antihormone exposure.

SETTING

Academic research center.

PATIENT(S)

Not applicable.

INTERVENTIONS(S)

Exposure of leiomyoma cell lines to 17β-E₂, medroxyprogesterone acetate (MPA), UPA, and fulvestrant.

MAIN OUTCOME MEASURE(S)

Messenger RNA expression quantified with the use of RNASeq analysis and quantitative real-time polymerase chain reaction (qRT-PCR). Protein levels quantified by means of Western blot analysis. Immunohistochemistry (IHC) on placebo- and UPA-treated patient uterine tissue specimens.

RESULT(S)

Expression of NTM in human uterine leiomyoma specimens according to RNASeq was increased compared with myometrium (5.22 ± 0.57-fold), which was confirmed with the use of qRT-PCR (1.95 ± 0.05). Furthermore, NTM protein was elevated in leiomyoma tissue compared with matched myometrium (2.799 ± 0.575). IHC revealed increased staining intensity in leiomyoma surgical specimens compared with matched myometrium of placebo patients. Western blot analysis in immortalized leiomyoma cell lines demonstrated an up-regulation of NTM protein expression (2.4 ± 0.04). Treatment of leiomyoma cell lines with 17β-E₂ yielded a 1.98 ± 0.11-fold increase in NTM protein expression; however, treatment with fulvestrant showed no significant change compared with control. Leiomyoma cell lines demonstrated a 1.91 ± 0.97-fold increase in NTM protein expression after progesterone treatment. RNASeq analysis demonstrated a reduced expression in patient leiomyoma after UPA treatment (0.75 ± 0.14). Treatment of leiomyoma cells with UPA demonstrated a reduced total NTM protein amount (0.54 ± 0.31) in patients, which was confirmed with the use of IHC (UPA10 147.2 ± 9.40, UPA20 182.8 ± 8.98). In vitro studies with UPA treatment revealed a concentration-dependent effect that supported these findings.

CONCLUSION(S)

NTM, a neural cell adhesion molecule, is increased in leiomyoma compared with myometrium in patient tissue and in vitro models after estrogen and progesterone treatment. Down-regulation of expression occurs after UPA treatment, but not after fulvestrant exposure.

CLINICAL TRIAL REGISTRATION NUMBER

NCT00290251.

The potential role of elagolix for treating uterine bleeding associated to uterine myomas

INTRODUCTION

Uterine myomas represents a widespread gynecological disease of women in reproductive age. Although surgery remains the first choice for treating most patients, in the last years, new medical approaches have been considered in order to ameliorate heavy menstrual bleeding (HMB) related to their presence. Elagolix is a second-generation gonadotropin-releasing hormone (GnRH) antagonist under investigation for the long-term treatment of uterine myomas.

AREAS COVERED

The aim of this drug evaluation is to give a complete overview of pharmacokinetic and pharmacodynamic data on elagolix for treating HMB related to uterine myomas and to report the results of the current clinical trials in this setting.

EXPERT OPINION

In two previous phase II studies, this drug succeeded in ameliorating blood loss and quality of life of patients affected by uterine myomas with a good safety profile. Three phase III trials (ELARIS UF-I, UF-II, and EXTEND) investigated the efficacy, tolerability, and safety of elagolix at 300 mg twice daily with add-back therapy. The primary endpoint, consisting in the reduction in HMB compared to placebo, was met in the majority of patients under treatment. Currently, elagolix is under investigation in two other ongoing multicenter phase III clinical studies.

Organotypic culture as a research and preclinical model to study uterine leiomyomas

Organotypic cultures of tissue slices have been successfully established in lung, prostate, colon, gastric and breast cancer among other malignancies, but until now an ex vivo model based on tissue slices has not been established for uterine leiomyoma. In the present study, we describe a method for culturing tumour slides onto an alginate scaffold. Morphological integrity of tissue slices was maintained for up to 7 days of culture, with cells expressing desmin, estrogen and progesterone receptors. Driver mutations were present in the ex vivo slices at all-time points analyzed. Cultivated tumour slices responded to ovarian hormones stimulation upregulating the expression of genes involved in leiomyoma pathogenesis. This tissue model preserves extracellular matrix, cellular diversity and genetic background simulating more in-vivo-like situations. As a novelty, this platform allows encapsulation of microspheres containing drugs that can be tested on the ex vivo tumour slices. After optimizing drug release rates, microspheres would then be directly tested in animal models through local injection.

Epidemiology and management of uterine fibroids

Uterine leiomyomas are one of the most common and yet understudied diseases in women. These tumors, commonly known as fibroids, affect women mainly during their reproductive years and are diagnosed in up to 70% of white women and more than 80% of women of African ancestry during their lifetime. This disease has a profound impact on health care delivery and costs worldwide. Though most women with fibroids are asymptomatic, approximately 30% of them will present with severe symptoms which can include abnormal uterine bleeding, anemia, pelvic pain and pressure, back pain, urinary frequency, constipation, or infertility, and will require intervention. Furthermore, fibroids have been associated with poor obstetrical outcomes. The current options for symptomatic fibroid treatment include expectant, medical, and surgical management, and interventional radiology procedures. This article reviews the recent progress and available management strategies for uterine fibroids and highlights areas where further research is needed to find new therapeutic targets and better personalize treatments.

Genomic evidence sheds light on the genetic mechanisms of musk secretion in muskrats

Adult male muskrat (Ondatra zibethicus) has a pair of scent glands which secret musk to attract females during the breeding stage. The goal of the present study was to investigate the genetic mechanisms of musk secretion of muskrats at the whole genome level. Comparative genomics illustrated obvious expansion in 809 gene families, of which nine gene families played pivotal roles in steroid biosynthesis, possibly related to muskrat musk secretion. We identified 1112 positively selected genes (PSGs) in the muskrat, including estrogen receptor 1 (ER1), an important influencing factor to the weight and size of the scented glands of muskrats. HSD17B3, HSD17B4, CYP7B1 and CYP17B1, crucial to steroid hormone biosynthesis, were under strong positive selection in the muskrat, and phylogenetic analysis of HSD and CYP450 classes revealed high gene diversity. Functional enrichment revealed many pathways associated with musk secretion and/or growth and degeneration of scented gland significantly, such as peroxisome, PI3K-Akt signaling pathway, apoptosis, and prostate cancer. Two muskrat-specific missense mutations (Pro237Thr and Ser297Ile) were detected in LIPC, which were reported to be involved cholesterol metabolic process. More importantly, the missense mutations discovered in LIPC were classified as deleterious by PolyPhen-2, possibly affecting the musk secretion of muskrats.

Leiomyoma phosphoproteins involved in inhibition of oxidative stress and synthesis of reactive oxygen species

Uterine leiomyomas are benign smooth muscle cell tumors originating from the myometrium. The present study focused on leiomyoma and myometrium phosphoproteome enrichment by using immobilized metal affinity chromatography (IMAC). The phosphoproteome was analyzed by two‑dimensional gel electrophoresis coupled with mass spectrometry. Western blotting was used for data validation. The results from IMAC identified 26 proteins significantly differentially phosphorylated in leiomyomas compared with normal myometrium. Three upregulated proteins (peroxiredoxin 2, protein disulfide isomerase family A member 3 and peroxiredoxin 4) were further validated by western blotting. Ingenuity pathway analysis revealed that four phosphoproteins were involved in the inhibition of oxidative stress and synthesis of reactive oxygen species. The present results demonstated for the first time an association between oxidative stress and phosphorylation in leiomyoma development.

Uterine fibroid management: Today and tomorrow

Current treatments for fibroids are mainly surgical and expensive, so alternatives need to be found. It is, therefore, vital to develop and evaluate alternatives to surgical procedures, especially when fertility preservation is the goal. Selective progesterone receptor modulators (SPRMs) are synthetic compounds that have either an agonistic or antagonistic impact on target tissues determined by their binding to progesterone receptors. Their mixed activity depends on recruitment of cofactors that regulate transcription along so-called genomic pathways, as well as nongenomic interactions with other signaling pathways. There is no doubt that surgery remains indicated in some instances, but we must now establish whether use of SPRMs (notably ulipristal acetate) allows less invasive surgery or even complete avoidance of surgery. Long-term intermittent administration of ulipristal acetate will undoubtedly change our approach to the management of uterine fibroids according to the International Federation of Gynecology and Obstetrics classification, which provides a comprehensive basis for different treatment options. When considering less invasive techniques (uterus-sparing options like myomectomy), the choice is guided by the size, number and location of fibroids, as well as the personal experience of the gynecologist and available equipment. There is now a growing body of evidence pointing to the crucial role of progesterone pathways in the pathophysiology of uterine fibroids. SPRMs should, therefore, be considered an alternative to surgical therapy, or at least an adjunct to surgery, as illustrated in the algorithms. © 2019 Japan Society of Obstetrics and Gynecology.

Phosphoproteins Involved in the Inhibition of Apoptosis and in Cell Survival in the Leiomyoma

Uterine leiomyomas are benign smooth muscle cell tumors originating from the myometrium. In this study we focus on leiomyoma and normal myometrium phosphoproteome, to identify differentially phosphorylated proteins involved in tumorigenic signaling pathways, and in anti-apoptotic processes and cell survival. We obtained paired tissue samples of seven leiomyomas and adjacent myometria and analyzed the phosphoproteome by two-dimensional gel electrophoresis (2-DE) combined with immobilized metal affinity chromatography (IMAC) and Pro-Q Diamond phosphoprotein gel stain. We used mass spectrometry for protein identification and Western blotting for 2-DE data validation. Quantities of 33 proteins enriched by the IMAC approach were significantly different in the leiomyoma if compared to the myometrium. Bioinformatic analysis revealed ten tumorigenic signaling pathways and four phosphoproteins involved in both the inhibition of apoptosis and cell survival. Our study highlights the involvement of the phosphoproteome in leiomyoma growth. Further studies are needed to understand the role of phosphorylation in leiomyoma. Our data shed light on mechanisms that still need to be ascertained, but could open the path to a new class of drugs that not only can block the growth, but could also lead to a significant reduction in tumor size.

Lower prevalence of non-cavity-distorting uterine fibroids in patients with polycystic ovary syndrome than in those with unexplained infertility

OBJECTIVE

To study whether there is a difference in the prevalence of non-cavity-distorting uterine fibroids between infertile patients with polycystic ovary syndrome (PCOS) and those with unexplained infertility (UI).

DESIGN

A secondary analysis of data from three randomized clinical trials.

SETTING

Academic health centers.

PATIENT(S)

A total of 2,249 patients with normal uterine cavities.

INTERVENTIONS(S)

None.

MAIN OUTCOME MEASURE(S)

The presence or absence of non-cavity-distorting fibroids.

RESULT(S)

Compared with women with UI, those with PCOS were younger, had a higher body mass index, and were more likely to be Hispanic or African American, with a lower percentage of previous conception and live birth, a higher percentage of current smokers, a lower percentage of current alcohol users, and higher total testosterone, fasting insulin, and homeostasis-model-assessment insulin resistance. The prevalence of women with non-cavity-distorting uterine fibroids was lower in women with PCOS than in those with UI (6.7% vs. 12.4%); this result held after patients were divided into Black and non-Black or into three different body mass index groups. After adjustment for all the other variables in the final model, patients with PCOS had a significantly lower prevalence of fibroids than those with UI (odds ratio 0.54). No differences in the prevalence of non-cavity-distorting fibroids with any dimensions ≥4 cm or the volume of the largest fibroid was found between the two groups.

CONCLUSION(S)

A lower prevalence of non-cavity-distorting uterine fibroids was found in infertile women with PCOS than in those with UI.

Uterine stem cells: from basic research to advanced cell therapies

BACKGROUND

Stem cell research in the endometrium and myometrium from animal models and humans has led to the identification of endometrial/myometrial stem cells and their niches. This basic knowledge is beginning to be translated to clinical use for incurable uterine pathologies. Additionally, the implication of bone marrow-derived stem cells (BMDSCs) in uterine physiology has opened the field for the exploration of an exogenous and autologous source of stem cells.

OBJECTIVE AND RATIONALE

In this review, we outline the progress of endometrial and myometrial stem/progenitor cells in both human and mouse models from their characterization to their clinical application, indicating roles in Asherman syndrome, atrophic endometrium and tissue engineering, among others.

SEARCH METHODS

A comprehensive search of PubMed and Google Scholar up to December 2017 was conducted to identify peer-reviewed literature related to the contribution of bone marrow, endometrial and myometrial stem cells to potential physiological regeneration as well as their implications in pathologies of the human uterus.

OUTCOMES

The discovery and main characteristics of stem cells in the murine and human endometrium and myometrium are presented together with the relevance of their niches and cross-regulation. The current state of advanced stem cell therapy using BMDSCs in the treatment of Asherman syndrome and atrophic endometrium is analyzed. In the myometrium, the understanding of genetic and epigenetic defects that result in the development of tumor-initiating cells in the myometrial stem niche and thus contribute to the growth of uterine leiomyoma is also presented. Finally, recent advances in tissue engineering based on the creation of novel three-dimensional scaffolds or decellularisation open up new perspectives for the field of uterine transplantation.

WIDER IMPLICATIONS

More than a decade after their discovery, the knowledge of uterine stem cells and their niches is crystalising into novel therapeutic approaches aiming to treat with cells those conditions that cannot be cured with drugs, particularly the currently incurable uterine pathologies. Additional work and improvements are needed, but the basis has been formed for this therapeutic application of uterine cells.

New Insights of Uterine Leiomyoma Pathogenesis: Endocannabinoid System

Background

The aim of this study was to determine if components of the endocannabinoid system are modulated in uterine leiomyomas (fibroids). Components studied included cannabinoid receptors 1 (CB1) and 2 (CB2); the G protein-coupled receptor GPR55; transient potential vanilloid receptor 1 (TRPV1) and the endocannabinoid modulating enzymes N-acylphosphatidylethanolamine-specific phospholipase D (NAPE-PLD) and fatty acid amide hydrolase (FAAH), and their N-acylethanolamine (NAE) ligands: N-arachidonylethanolamine (AEA), N-oleoylethanolamine (OEA), and N-palmityolethanaolamine (PEA).

Material/Methods

Transcript levels of CB1, CB2, TRPV1, GPR55, NAPE-PLD, and FAAH were measured using RT-PCR and correlated with the tissue levels of the 3 NAEs in myometrial tissues. The tissues studied were: 1) fibroids, 2) myometrium adjacent/juxtaposed to the fibroid lesions, and 3) normal myometrium. Thirty-seven samples were processed for NAE measurements and 28 samples were used for RT-PCR analyses.

Results

FAAH expression was significantly lower in fibroids, resulting in a NAPE-PLD: FAAH ratio that favors higher AEA levels in pre-menopausal tissues, whilst PEA levels were significantly lower, particularly in post-menopausal women, suggesting PEA protects against fibroid pathogenesis. The CB1: CB2 ratio was lower in fibroids, suggesting that loss of CB1 expression affects the fibroid cell phenotype. Significant correlations between reduced FAAH, CB1, and GPR55 expression and PEA in fibroids indicate that the loss of these endocannabinoid system components are biomarkers of leiomyomata.

Conclusions

Loss of expression of CB1, FAAH, GPR55, and PEA production are linked to the pathogenesis of uterine fibroids and further understanding of this might eventually lead to better disease indicators or the development of therapeutic potentials that might eventually be used in the management of uterine fibroids.

Fibroid management in premenopausal women

Uterine fibroids are the most common tumors affecting premenopausal women, responsible for bleeding, pain, and reduced quality of life. When symptomatic, their management mainly involves surgery, which is all too often radical (hysterectomy). While surgical options sparing the uterus (hysteroscopic and laparoscopic myomectomy) and other non-surgical approaches do indeed exist, drug-based therapies are associated with lower costs and morbidity rates. Since progesterone is required for fibroid growth, gonadotropin agonists have been used to control bleeding and decrease fibroid volume, but they only represent a temporary remedy due to adverse events. Ulipristal acetate (UPA), a selective progesterone receptor modulator, is indicated for fibroid management. It is safe, provides fast control of bleeding, and causes sustained fibroid volume reduction in the vast majority of cases (80%). Indeed, UPA-treated fibroids shrink by a combination of inhibition of cell proliferation, stimulation of cell death, and fibrosis resorption. In the case of symptom recurrence, repeated intermittent 3-month courses of daily UPA considerably maximize the impact of treatment, sometimes resulting in complete disappearance of treated fibroids. Despite the therapeutic dose of UPA being very well tolerated, patients with liver anomalies or disorders should be excluded at screening according to European Medicines Agency-Pharmacovigilance Risk Assessment Committee (PRAC) recommendations. We therefore propose new algorithms for fibroid management in premenopausal women with symptomatic fibroids, depending on their localization, the patient's wishes, and clinical response, while monitoring liver enzymes and bilirubin, as recommended by the PRAC, in order to minimize the risks of possible liver toxicity.

The ontogeny of myometrial stem cells in OCT4-GFP transgenic mouse model

BACKGROUND

Myometrium, the muscular wall of the uterus, is an active organ markedly remodeled during a woman's reproductive life, especially during pregnancy. Different studies using the 5-bromo-2'-deoxyuridine and side population methods in murine and human myometrium have suggested the presence of somatic stem cells in this tissue because of its remarkable regenerative capacity. Recently, our group has developed a surface-marker (Stro1/CD44)-specific approach to isolate and characterize myometrial somatic stem cells (SSCs) from humans and rats.

OBJECTIVE

In this study, we aimed to identify and localize the putative myometrial stem cell population in the murine uterus by using the specific surface markers, Nanog/CD44.

METHODS

Uteri from OCT4-GFP transgenic mice at different early-life time points were analyzed via single and double immunohistochemistry to co-localize myometrial stem cell marker CD44 with other general stemmness markers, e.g., Nanog and Oct-4. Finally, we correlated the frequency of myometrial stem cells in vivo with the expression of sex steroid hormone receptors, estrogen receptor α (ERα), and progesterone receptors A and B (PR A&B).

RESULTS

Nanog⁺/CD44⁺ stem cells were present in murine myometrium. Both stem cell markers were shown to co-localize with Oct-4 expression. Time-course experiments demonstrated that their percentages were significantly lower at the pre-sexual age of 1 week than at the sexually mature ages of 3 to 24 weeks. Importantly, both ERα and PR A&B were abundantly expressed in the myometrium at ages 1, 3 and 4 weeks.

CONCLUSIONS

We demonstrated that murine CD44⁺ myometrial cells have features of somatic stem cells with the expression of typical undifferentiated markers. Furthermore, our results suggest that myometrial stem cells are sex steroid hormone dependent, likely via paracrine pathway, and increase in numbers with reproductive maturity and rise in serum estrogen and progesterone levels around 3 weeks of age in mice. The abundance and early onset expression of ER/PR emphasize the vulnerability of neonatal myometrium to environmental endocrine disruptors which can potentially lead to permanent reprograming and adult onset of myometrial disorders such as uterine fibroids.

Porcine intestinal lymphoid tissues synthesize estradiol

Estradiol (17β-estradiol) is synthesized primarily in the gonads of both sexes and regulates the development and function of reproductive organs. Recently, we reported that intestinal lymphocyte homeostasis is regulated by estradiol synthesized de novo in the endothelial cells of the high endothelial venules (HEVs) of mesenteric lymph nodes and Peyer's patches in mice. This observation prompted us to hypothesize that HEVs of intestinal lymphoid tissues are sites of estradiol synthesis across species. In this study, we examined whether estradiol is synthesized in the intestinal lymphoid tissues of adolescent piglets. Comparisons of estradiol levels in blood and tissue showed that estradiol concentrations in mesenteric lymph nodes and Peyer's patches were significantly higher than the level in serum. Reverse transcription polymerase chain reaction showed that porcine intestinal lymphoid tissues express mRNAs for steroidogenic enzymes (StAR, 17β-Hsd,3β-Hsd, Cyp17a1, and Cyp19a1), and immunohistochemical results in ilial tissue showed expression of aromatase (CYP19) in Peyer's patch-localized endothelial cells of HEVs. When mesenteric lymph node and Peyer's patch tissues were cultured in vitro, they produced estradiol. Taken together, the results indicate that mesenteric lymph nodes and Peyer's patches are sites of estradiol synthesis in adolescent piglets.

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.

HMGA2 and MED12 alterations frequently co-occur in uterine leiomyomas

OBJECTIVE

Around 70% of uterine leiomyomas show MED12 mutations while overexpression of HMGA2 mRNA is also highly frequent in fibroids. However, previous studies suggested that alterations in both genes are mutually exclusive. In the present study, we searched for mutation in MED12 and analyzed the expression of HMGA2 in 20 uterine leiomyomas and their matched myometrium.

METHODS

Normal and tumor tissue obtained from premenopausal women who underwent hysterectomy were collected after surgery and DNA, RNA and proteins were isolated and analyzed for MED12 mutations using Sanger sequencing, HMGA2 mRNA expression by quantitative PCR and HMGA2 protein detection by western blot and immunohistochemistry.

RESULTS

75% of the tumors displayed MED12 mutation while 65% of them showed overexpression of HMGA2 mRNA in leiomyomata compared to myometrial tissues (p = 0,0008). Interestingly, 50% of the tumors showed mutations in MED12 and overexpression of HMGA2 mRNA simultaneously, suggesting that alterations in both genes are relatively frequent in uterine leiomyomas.

CONCLUSIONS

Contrary to the present findings, former studies showed that mutations in MED12 and overexpression of HMGA2 are mutually exclusive. Here, we observed that overexpression of HMGA2 mRNA in tumors measured by quantitative PCR and compared to myometrium is a common phenomenon in fibroids and is frequently associated with MED12 mutations. In addition, the common clonal origin of tumors overexpressing HMGA2 mRNA and its expression in few myometrial tissue points to HMGA2 up-regulation as an early event in leiomyoma tumorigenesis.