Aromatase and other steroidogenic genes in endometriosis: translational aspects

Association of COX-2 Selectivity in Pain Medication Use with Endometriosis Incidence: Retrospective Cohort Study

PURPOSE

This retrospective cohort study aimed to investigate the association between the use of pain medications with varying cyclooxygenase-2 (COX-2) selectivity and the incidence of endometriosis (EMS) in women.

MATERIALS AND METHODS

Medical records from January 1, 1994, to December 31, 2022, were retrospectively analyzed. The cohort included 33406 patients diagnosed with any pain-related condition who were prescribed either selective COX-2 inhibitors or nonsteroidal anti-inflammatory drugs (NSAIDs). Patients were followed for up to 5 years from the cohort entry date. The incidence of EMS was compared between the two medication groups using Cox proportional hazards models, adjusting for confounding factors such as age, past drug use, and prior diagnosis.

RESULTS

The incidence rates of EMS were 3.00 per 1000 person-years in the COX-2 inhibitor group and 3.97 per 1000 person-years in the NSAIDs group. After adjustment for confounders, the hazard ratio for EMS incidence in the COX-2 inhibitor group compared to the NSAIDs group was 0.77 [95% confidence interval (CI), 0.63 to 0.93; p<0.01], indicating a significantly lower risk in the COX-2 inhibitor group. Subgroup analysis revealed that this association was particularly significant in younger women aged 20-44 years, with a hazard ratio of 0.71 (95% CI, 0.54 to 0.95; p<0.05) in this age group.

CONCLUSION

The findings suggest that COX-2 inhibitors may reduce the incidence of EMS compared to traditional NSAIDs, highlighting their potential as a strategic option for managing EMS, particularly among younger women. Further prospective studies are needed to confirm these findings.

Progressively Diminished Prostaglandin E2 Signaling in Concordance with Increasing Fibrosis in Ectopic Endometrium

The prostaglandin E2 (PGE2) signaling has traditionally been viewed to play a pivotal role in endometriosis, linking inflammation and hyperestrogenism. We have previously reported that asectopic endometrium becomes more fibrotic, the expression of both COX-2 and PGE2 receptors (EP2 and EP4) are reduced. This study further investigatedwhether the expression levels of genes involved in the biosynthesis and metabolism of PGE2in ectopic endometrium diminish in concordance with increasing lesional fibrosis. We performed immunohistochemistry analyses of COX-2, mPGES-1, mPGES-2, cPGES, 15-PGDH, EP2 and EP4 and Masson trichrome staining for ovarian endometrioma (OE), adenomyosis (AD), and deep endometriosis (DE) tissue samples and control endometrial tissue samples (CT). Gene and protein expression analyses were performed by real-time RT-PCR and Western blotting, respectively. We found that as the extent of lesional fibrosis increased, immunoexpression of COX-2, mPGES-1/2, cPGES, EP2 and EP4 in OE lesions was increased but no change in these genes/proteins in DE lesions as compared with CT. Immunoexpression of COX-2 was found to be reduced while that of 15-PGDH was found to be elevated in DE lesions. In AD lesions, only EP2 and COX-2 were overexpressed. Thus, our data indicate that when the extent of lesional fibrosis is high, the PGE2 signaling pathway is depressed, manifesting as reduced COX-2 expression and elevated expression of 15-PGDH. They underscore the fact that not all ectopic endometria are the same and equal, and highlight the importance of the extracellular matrix in shaping the lesional behavior and response to drug treatment.

Endometriosis and autoimmunity

Endometriosis is a female-specific chronic condition that affects 1 in 10 women and other individuals with a uterus worldwide with common symptoms that include pelvic pain and infertility. Reliable and effective non-invasive biomarkers for endometriosis do not exist, and therefore currently a diagnosis of endometriosis requires direct visualization of lesions at surgery. Similarly, few safe and effective management strategies exist for endometriosis, with hormonal interventions and surgery only providing temporary symptom control. The development of endometriosis involves the implantation and proliferation of ectopic endometrial cells which triggers local and systemic inflammation and fibrosis. While multiple genetic, environmental, and lifestyle factors appear to influence the natural history of endometriosis, chronic inflammation is a hallmark feature associated with development and progression of the disease. Data further shows that endometriosis commonly co-occurs with autoimmune diseases, adding evidence that immune dysfunction likely contributes to the pathogenesis of this disorder. Specific innate and adaptive immune system drivers of endometriosis remain to be identified and additional research is needed to elucidate the mechanistic underpinnings of this debilitating disease. In this narrative review, we discuss the shared biological mechanisms and plausible immune-related connections between endometriosis and autoimmunity.

Deciphering the role of circulating miRNAs in the etiology and pathophysiology of endometriosis: An updated compiled review

Endometriosis is characterized by the presence of endometrial tissue outside of the uterus. It is a benign chronic condition with incapacitating symptoms like infertility and pelvic pain. Endometriosis has a detrimental impact on the reproductive health of women, placing a heavy financial strain on the medical system. It is a multifactorial disorder governed by numerous mechanisms or risk factors that contribute to the pathologies of the disease. With limitations in diagnostics techniques, it is challenging to detect the disease at an initial stage. In around 1 % of endometriotic patients malignant state may reach, leading to severe consequences. To overcome such challenges, at present, numerous circulating miRNAs have been studied in plasma or serum samples from patients with endometriosis to develop a non-invasive diagnostic biomarker-based tool to identify the disease early. Our review compiles the miRNAs in bodily fluids that are linked with endometriosis-related mechanisms, which may serve as a potential biomarker. Some of these mechanisms are common in both cancer and endometriosis. Additionally, we have also emphasised the miRNAs with a putative role in cancer development and progression that could be used as a biomarker. This may further aid in protecting the 1 % of affected females from ovarian, breast, and in some cases endometrial cancer. We have come across several miRNAs associated with multiple mechanisms associated with endometriosis. miR-199a and miRNAs-let-7 family are some of the most common miRNAs that assist in multiple mechanisms such as cell proliferation, invasion, apoptosis, and epithelial-mesenchymal transition. Strategic planning and additional investigation into the identified miRNAs would make them a viable therapeutic target for the optimal management of endometriosis.

The Molecular and Cellular Mechanisms of Endometriosis: From Basic Pathophysiology to Clinical Implications

Endometriosis is a complex gynecological disorder characterized by endometrial-like tissue growing outside the uterus, leading to chronic pain, infertility, and reduced quality of life. Its pathophysiology involves genetic, epigenetic, immune, and molecular factors. Theories such as retrograde menstruation, coelomic metaplasia, and stem cell involvement explain lesion formation. Endometrial mesenchymal stem cells (eMSCs) and epithelial progenitors (eEPs) contribute to lesion establishment by adhering to peritoneal surfaces, proliferating, and differentiating into ectopic tissue. Aberrant adhesion molecules, inflammatory cytokines, and molecular pathways like PI3K/Akt and Wnt/β-catenin drive proliferation, angiogenesis, and resistance to apoptosis. Elevated estrogen levels and progesterone resistance further promote lesion growth and immune evasion. Immune dysfunction, including altered macrophage activity and reduced natural killer (NK) cell function, contributes to inflammation and lesion persistence. Pain is linked to prostaglandin E2 (PGE2) and nerve infiltration, emphasizing the need for targeted pain management. Current therapies, such as GnRH agonists, suppress ovarian hormone production but face limitations in long-term efficacy and side effects. Integrating molecular insights into clinical practice may advance diagnostics and treatment, with emerging approaches focusing on molecular pathways, immune modulation, and hormonal regulation for more effective, personalized therapies. Future research should unravel the complex mechanisms driving endometriosis to improve patient outcomes.

Hormonal Therapies before in vitro fertilization in women with endometriosis: The Minotaur's Labyrinth and the Ariadne's Thread

Endometriosis-related infertility is one of the most debated topics in reproductive medicine. In recent years, prolonged pre-cycle hormonal regimens gained attention as a mean of improving the assisted reproduction technologies (ART) success rates in endometriosis patients. GnRH agonists, dienogest, medroxyprogesterone acetate, and aromatase inhibitors are the most studied medications. Conflicting results and a high risk of bias exist in almost all of the conducted studies in the field. However, current evidence suggests that pre-cycle treatment with GnRH agonists may be beneficial for patients with stage III/IV endometriosis. Dienogest and medroxyprogesterone acetate-based progestin-primed ovarian stimulation protocol was shown to be comparable to the prolonged GnRH agonists protocol. Finally, aromatase inhibitors seem to be of limited benefit to the assisted reproductive outcomes of endometriosis patients. Although it is challenging to draw any clinical conclusions, pre-cycle hormonal treatments seem to be best indicated in endometriosis patients who had previously failed ART treatment.

Low Diet Quality and Nutritional Knowledge in Women with Endometriosis: A Pilot Study

Endometriosis is a chronic gynecological disease characterized by ectopic endometrial tissue outside the uterus that can cause chronic pain, dysmenorrhea, fatigue, and infertility. The aim of this study was to assess diet quality and nutritional knowledge of women with endometriosis. A questionnaire was used to collect data on lifestyle, dietary habits and nutritional knowledge from 90 women. More than 80% of women with endometriosis (82.2%) confirmed that diet and lifestyle are related to the progression of endometriosis. After being diagnosed with endometriosis, 77.3% of respondents reported a change in their dietary habits and made various changes to their diet by increasing or eliminating the consumption of certain foods. The majority declared reducing pro-inflammatory products, increasing anti-inflammatory foods, including the consumption of vegetables and fruits, avoiding white/or red/or processed meat, and avoiding sweets. Nevertheless, diet quality as assessed by the pro-healthy diet index (pHDI-10) and the Mediterranean Diet Score (MDS) showed a low intensity of consumption of pro-healthy food (average pHDI-10 value 31.4%; MDS 7.55/14 points, p = 0.0001). Women with endometriosis reported lower than recommended consumption of fruits, vegetables, dairy products and whole grains. A higher percentage of healthy controls had a "good" level of nutritional knowledge than women with endometriosis. The results of our study highlight the need to improve diet quality and nutritional knowledge among women with endometriosis as well as developing targeted dietary recommendations to help improve well-being and reduce the pain symptoms of endometriosis.

Expression Profiles of Genes Related to Development and Progression of Endometriosis and Their Association with Paraben and Benzophenone Exposure

Increasing evidence has been published over recent years on the implication of endocrine-disrupting chemicals (EDCs), including parabens and benzophenones in the pathogenesis and pathophysiology of endometriosis. However, to the best of our knowledge, no study has been published on the ways in which exposure to EDCs might affect cell-signaling pathways related to endometriosis. We aimed to describe the endometriotic tissue expression profile of a panel of 23 genes related to crucial cell-signaling pathways for the development and progression of endometriosis (cell adhesion, invasion/migration, inflammation, angiogenesis, and cell proliferation/hormone stimulation) and explore its relationship with the exposure of patients to parabens (PBs) and benzophenones (BPs). This cross-sectional study included a subsample of 33 women with endometriosis from the EndEA study, measuring their endometriotic tissue expressions of 23 genes, while urinary concentrations of methyl-, ethyl-, propyl-, butyl-paraben, benzophenone-1, benzophenone-3, and 4-hydroxybenzophenone were determined in 22 women. Spearman's correlations test and linear and logistic regression analyses were performed. The expression of 52.2% of studied genes was observed in >75% of endometriotic tissue samples and the expression of 17.4% (n = 4) of them in 50-75%. Exposure to certain PB and BP congeners was positively associated with the expression of key genes for the development and proliferation of endometriosis. Genes related to the development and progression of endometriosis were expressed in most endometriotic tissue samples studied, suggesting that exposure of women to PBs and BPs may be associated with the altered expression profile of genes related to cellular pathways involved in the development of endometriosis.

The Pathological Role of miRNAs in Endometriosis

Association studies investigating miRNA in relation to diseases have consistently shown significant alterations in miRNA expression, particularly within inflammatory pathways, where they regulate inflammatory cytokines, transcription factors (such as NF-κB, STAT3, HIF1α), and inflammatory proteins (including COX-2 and iNOS). Given that endometriosis (EMS) is characterized as an inflammatory disease, albeit one influenced by estrogen levels, it is natural to speculate about the connection between EMS and miRNA. Recent research has indeed confirmed alterations in the expression levels of numerous microRNAs (miRNAs) in both endometriotic lesions and the eutopic endometrium of women with EMS, when compared to healthy controls. The undeniable association of miRNAs with EMS hints at the emergence of a new era in the study of miRNA in the context of EMS. This article reviews the advancements made in understanding the pathological role of miRNA in EMS and its association with EMS-associated infertility. These findings contribute to the ongoing pursuit of developing miRNA-based therapeutics and diagnostic markers for EMS.

A Large Ovarian Endometrioma Occupying the Abdominal Cavity in a Postmenopausal Patient: A Case Report

Endometriosis is defined by the presence of endometrial-like glands and/or stroma outside the uterus. The prevalence of endometriosis in postmenopausal women is reported to be 2.55%, which is much lower than that in reproductive-aged women. Ovarian endometriomas are the most common form of endometriosis. However, these form only 4.3% of ovarian masses in patients in the sixth decade of life. In this manuscript, we report the case of a 60-year-old patient who was referred to our department with an external diagnosis of an abdominal mass. The patient was in good general condition and asymptomatic. A computed tomography scan revealed the presence of a cystic mass originating from the right adnexa and measuring 26 cm. No signs of malignancy were observed. Due to the cyst's size, a midline laparotomy and a bilateral salpingo-oophorectomy were performed successfully. A postoperative histopathologic examination confirmed the diagnosis of an ovarian endometrioma with no signs of hyperplasia or atypia. Cases of postmenopausal large ovarian endometriomas are few. However, due to the risk of malignant transformation, an oophorectomy could be considered the treatment of choice, even in asymptomatic patients.

Is neonatal uterine bleeding responsible for early-onset endometriosis?

BACKGROUND

It has been hypothesized that the origin of early-onset endometriosis could be from endometrial mesenchymal stem cells (eMSCs) in neonatal uterine blood (NUB). There is no information on the possible mechanistic basis linking an association between NUB/neonatal endometrium and development of early-onset endometriosis. In this study we performed a series of experiments to clarify the mechanistic link between NUB and/or neonatal endometrium and development of early-onset endometriosis.

METHODS

We retrospectively collected postmortem neonatal endometria (n = 15) and prospectively collected NUB (n = 18) of female babies for the analysis of different biological markers including eMSCs. Immunohistochemical analysis of neonatal endometria was performed to examine the expression patterns of ovarian steroid receptors (ER/PGR), decidualization (prolactin, IGFBP1), pre-decidualization (Glycodelin A, α-SMA), proliferation (Ki-67 index), vascularity (CD31 + cells), immunocompetent CD68+, CD45+, CD56 + cells and some putative markers of eMSCs. Cell transfer method and immunocytochemistry were used to investigate the eMSCs and/or endometrial cells in NUB.

RESULTS

Immunohistochemical analysis of postmortem neonatal endometria revealed variable staining response to ER/PGR, decidual markers, and substantial proliferative and angiogenic activity. A moderate to strong immunoexpression of Glycodelin-A was found in both neonatal and adult endometria. The tissue infiltration of CD56+, CD45 + and CD68 + immunocompetent cells was significantly low in neonatal endometria than that in adult endometria (p = 0.0003, p < 0.0001, p = 0.034, respectively). No eMSCs or even endometrial cells were detected in NUB. However, a variable expression of some phenotypes of eMSCs (CD90/CD105) was found in neonatal endometria.

CONCLUSIONS

Based on our serial experiments we did not find any supporting evidence for the role of NUB in early-onset endometriosis. Neonatal endometria showed variable expression of ovarian steroid receptors, decidualization, and a substantial amount of proliferative and angiogenic activity. As an alternative mechanism, a significantly less tissue accumulation of immunocompetent cells in neonatal endometria may explain the survival of ER + and PGR + cells should they make entry into the pelvis and consequent development of early endometriosis with the onset of ovarian function. Future study with large sample size and application of modified technological tools is warranted to test the NUB hypothesis and to clarify their biological or clinical significance.

TRIAL REGISTRATION

not applicable.

The genomic landscape associated with resistance to aromatase inhibitors in breast cancer

Aromatase inhibitors (AI) are drugs that are widely used in treating estrogen receptor (ER)-positive breast cancer patients. Drug resistance is a major obstacle to aromatase inhibition therapy. There are diverse reasons behind acquired AI resistance. This study aims at identifying the plausible cause of acquired AI resistance in patients administered with non-steroidal AIs (anastrozole and letrozole). We used genomic, transcriptomic, epigenetic, and mutation data of breast invasive carcinoma from The Cancer Genomic Atlas database. The data was then separated into sensitive and resistant sets based on patients' responsiveness to the non-steroidal AIs. A sensitive set of 150 patients and a resistant set of 172 patients were included for the study. These data were collectively analyzed to probe into the factors that might be responsible for AI resistance. We identified 17 differentially regulated genes (DEGs) among the two groups. Then, methylation, mutation, miRNA, copy number variation, and pathway analyses were performed for these DEGs. The top mutated genes (FGFR3, CDKN2A, RNF208, MAPK4, MAPK15, HSD3B1, CRYBB2, CDC20B, TP53TG5, and MAPK8IP3) were predicted. We also identified a key miRNA - hsa-mir-1264 regulating the expression of CDC20B. Pathway analysis revealed HSD3B1 to be involved in estrogen biosynthesis. This study reveals the involvement of key genes that might be associated with the development of AI resistance in ER-positive breast cancers and hence may act as a potential prognostic and diagnostic biomarker for these patients.

Total Flavonoids of Polygala fallax Hemsl Induce Apoptosis of Human Ectopic Endometrial Stromal Cells through PI3K/AKT/Bcl-2 Signaling Pathway

OBJECTIVE

The objective of this study was to explore the inhibitory effect of total flavonoids of Polygala fallax Hemsl (PFHF) on human ectopic endometrial stromal cells (HEcESCs) and its mechanism.

DESIGN

The apoptosis, cell cycle, migration, and invasion ability of HEcESCs (Fresh human ovarian endometriosis tissue was used for primary culture) after PFHF treatment were detected, and the mechanism of action was explored.

MATERIALS

The Polygala fallax Hemsl (PFH), RPMI 1640 culture medium, Dulbecco's modified Eagle's medium (DMEM)/F-12, fetal bovine serum, penicillin/streptomycin, cell counting kit-8 (CCK-8) kit, trypsin, phenylmethylsulfonyl fluoride, radioimmunoprecipitation assay tissue/cell lysate, bicinchoninic acid protein concentration detection kits, protein loading buffer, the apoptosis and cell cycle extraction kits, the matrix glue, TRIzol Universal Reagent, the reverse transcription kit, AB HS Green qPCR Mix, the ECL chromogenic solution, enzyme labeling instrument, flow cytometry, automatic real-time fluorescence quantitative PCR instrument, Goat anti-rabbit, rabbit anti-β-actin, vimentin, phosphatidylinositol 3 kinase (PI3K), protein kinase B (AKT), B-cell lymphoma-2 (Bcl-2), Bcl-extra long (Bcl-xl), Bcl-2 associated death promoter (Bad) antibody, Alexa Fluor 594-labeled secondary antibody, the inverted microscope, the constant temperature carbon dioxide cell incubator.

SETTING

Five parts included introduction, materials and methods, results, discussion, and conclusion.

METHODS

The potential targets and pathways of PFHF in the treatment of endometriosis were predicted by network pharmacology. The effect of PFHF on the proliferation, apoptosis and cell cycle, migration, and invasion of HEcESCs was detected by CCK-8 method, flow cytometry, and Transwell chamber experiment. Label-free quantitative proteomics based on mass spectrometry was used to analyze the protein mass spectrum of differential expression of HEcESCs before and after PFHF, and the biological information was analyzed. The effects of PFHF on the mRNA and protein expression of pathway-related genes predicted in HEcESCs were detected by reverse transcription-quantitative polymerase chain reaction and Western blotting.

RESULTS

The network pharmacology predicts that PFHF treats endometriosis through PI3K/AKT signaling pathway. Compared with control group (DMEM/F-12 medium alone), the high dose PFHF can significantly reduce the viability, migration, and invasion of HEcESCs, increase the apoptosis rate of HEcESCs, and make the HEcESCs accumulated in G0/G1 phase in a time- and dose-dependent manner (p < 0.05). The analysis of label-free quantitative proteomics indicated that PFHF flavonoids may induce apoptosis of EESCs through PI3K/AKT signaling pathway. The results of RT-qPCR and Western blotting showed that the expressions of PI3K, AKT, Bcl-2, and Bcl-xl were significantly downregulated, while the bad expression was upregulated in HEcESCs treated with PFHF (p < 0.05).

LIMITATIONS

This research investigated the effects of PFHF on the stromal endometriotic cells only. So it is unknown how PFHF can affect the entire endometriotic lesion. And the research is carried out in vitro, which gives no impression about the bioavailability of the flavonoids.

CONCLUSION

PFHF reduces the expression of PI3K, AKT, Bcl-2, and Bcl-xl through the PI3K/AKT/Bcl-2 signaling pathway to inhibit HEcESCs proliferation, migration, and invasion and promote their apoptosis.

The Role of Dietary Fats in the Development and Treatment of Endometriosis

Endometriosis is an estrogen-dependent disease in women of childbearing age that affects approximately 5–15% of the female population. The etiology of endometriosis is complex, multifaceted, and not fully understood. In endometriosis, which is an estrogen-related chronic inflammatory condition, estrogen plays a major role in endometrial cellular growth. High estrogen levels could be another risk factor for developing endometriosis. The aim of this review is to update knowledge on the impact of dietary fats on the development of endometriosis and chronic inflammation in women with endometriosis and diet therapy. Dietary fat may be linked with the progression and development of endometriosis, but studies have been contradictory due to various issues including sample size, different study designs, and different methodological aspects. Results have shown that the risk of endometriosis may increase with a higher consumption of products rich in saturated fats, especially palmitic acid and trans-unsaturated fatty acids. Monounsaturated fats and omega-3 polyunsaturated fatty acids may likely be connected with a lower risk of developing endometriosis and with reductions in the severity of disease. Monounsaturated fats, omega-3 polyunsaturated fatty acids, and a suitable eicosapentaenoic acid to arachidonic acid ratio can be used in diet therapy to improve quality of life by reducing pain and inflammation. Further research is needed in order to fully understand the influence of dietary fats on the risk of development of this disease.

Current Updates on the Role of Microbiome in Endometriosis: A Narrative Review

Endometriosis affects approximately 6 to 10% of reproductive-age women globally. Despite much effort invested, the pathogenesis that promotes the development, as well as the progression of this chronic inflammatory disease, is poorly understood. The imbalance in the microbiome or dysbiosis has been implicated in a variety of human diseases, especially the gut microbiome. In the case of endometriosis, emerging evidence suggests that there may be urogenital-gastrointestinal crosstalk that leads to the development of endometriosis. Researchers may now exploit important information from microbiome studies to design endometriosis treatment strategies and disease biomarkers with the use of advanced molecular technologies and increased computational capacity. Future studies into the functional profile of the microbiome would greatly assist in the development of microbiome-based therapies to alleviate endometriosis symptoms and improve the quality of life of women suffering from endometriosis.

Network pharmacology and experimental validation to explore the potential mechanism of Sanjie Zhentong Capsule in endometriosis treatment

PURPOSE

Sanjie Zhentong Capsule (SZC) is gradually becoming widely used in the treatment of endometriosis (EMs) and has demonstrated an excellent curative effect in the clinic. However, the active components and mechanisms of Sanjie Zhentong Capsule (SZC) in the treatment of endometriosis (EMs) remain unclear, and further research is needed to explore the effects of Sanjie Zhentong Capsule (SZC).

MATERIALS AND METHODS

First, a drug target database of Sanjie Zhentong capsule (SZC) was established by consulting the TCMSP database and related literature. An endometriosis (EMs) disease target database was then established by consulting the GeneCards, OMIM and Drug Bank databases. The overlapping genes of SZC and EMs were determined, and protein-protein interactions (PPIs), gene ontology (GO) and Kyoto Gene and Genome Encyclopedia (KEGG) analyses were performed to predict the potential therapeutic mechanisms. Molecular docking was used to observe whether the key active ingredients and targets predicted by network pharmacology had good binding energy. Finally, in vitro experiments such as CCK-8, flow cytometry and RT-PCR assays were carried out to preliminarily verify the potential mechanisms.

RESULTS

Through the construction of a pharmacological network, we identified a total of 28 active components in SZC and 52 potential therapeutic targets. According to GO and KEGG enrichment analyses, the effects of SZC treatment may be related to oxidative stress, steroid metabolism, apoptosis and proliferation. We also experimentally confirmed that SZC can regulate the expression of steroid hormone biosynthesis-related genes, inhibit ectopic endometrial stromal cell (EESC) proliferation and oxidative stress, and promote apoptosis.

CONCLUSION

This study explored the potential mechanism of SZC in the treatment of EMs through network pharmacology and experiments, providing a basis for further future research on SZC in the treatment of EMs.

The role of progesterone receptor membrane component (PGRMC) in the endometrium

PGRMC is a non-classical receptor that mediates the non-genomic responses to progesterone and is distributed in different subcellular compartments. PGRMC belongs to the membrane-associated progesterone receptor (MAPR) family. Two PGRMC subtypes (PGRMC1 and PGRMC2) have been characterized, and both are expressed in the human endometrium. PGRMC expression is differentially regulated during the menstrual cycle in the human endometrium. Although PGRMC1 is predominantly expressed in the proliferative phase and PGRMC2 in the secretory phase, this expression changes in pathologies such as endometriosis, in which PGRMC2 expression considerably decreases, promoting progesterone resistance. In endometrial cancer, PGRMC1 is overexpressed, its activation induces tumors growth, and confers chemoresistance in the presence of progesterone. Thus, PGRMCs play a key role in progesterone actions in the endometrium.

Metformin as a Potential Treatment Option for Endometriosis

Endometriosis is a common disease in women of reproductive age, and its pathogenesis seems to be largely affected by hormone imbalance, inflammation, oxidative stress, and autophagy dysregulation. These pathophysiological disturbances interact with one another through mechanisms that are still awaiting elucidation. The aim of this article is to present current knowledge regarding the possibilities of using metformin in the pharmacological treatment of endometriosis. Metformin is an insulin sensitizer widely used for the treatment of type 2 diabetes mellitus. The pleiotropic effects of metformin are mainly exerted through the activation of AMP-activated protein kinase, which is the key cellular energy homeostasis regulator that inhibits mTOR, a major autophagy suppressor. Metformin regresses endometriotic implants by increasing the activity of superoxide dismutase. It is also an inhibitor of metalloproteinase-2, decreasing the levels of the vascular endothelial growth factor and matrix metalloproteinase-9 in animal studies. In endometriosis, metformin might modify the stroma-epithelium communication via Wnt2/β-catenin. With its unique therapeutic mechanisms and no serious side effects, metformin seems to be a helpful anti-inflammatory and anti-proliferative agent in the treatment of endometriosis. It could be a missing link for the successful treatment of this chronic disease.

HOXA10 Regulates the Synthesis of Cholesterol in Endometrial Stromal Cells

BACKGROUND

The expression of homeobox A10 (HOXA10) in endometrial stromal cells is regulated by steroid hormones, especially by estrogen. As a precursor molecule of estrogen, abnormal cholesterol metabolism is significantly positively correlated with endometriosis. The purpose of this study was to explore the regulation of HOXA10 on cholesterol synthesis in endometrial stromal cells.

METHOD

mRNA expression data of eutopic endometrial stromal cell (ESC) and ovarian endometriotic cysts stromal cell (OESC) were download from the Gene Expression Omnibus (GEO) databases. Overexpression and silence of HOXA10 were conducted in cultured ESC and subjected to mRNA sequencing. The differentially expressed genes (DEGs) were selected by analyzing the sequencing data. Weighted gene co-expression network analysis (WGCNA) was applied to identify the key genes associated with HOXA10. The methylation rate of HOXA10 CpGs and the correlation between HOXA10 expression and the methylation in eutopic endometrial tissue (EU) and ovarian cyst (OC) were analyzed.

RESULTS

HOXA10 in ESC was significantly higher expressed than that in OESC. Six key genes (HMGCR, MSMO1, ACAT2, HMGCS1, EBP, and SQLE), which were regulated by HOXA10, were identified from the salmon4 module by WGCNA. All these key genes were enriched in cholesterol synthesis. Moreover, the expression of HOXA10 was negatively related to its CpGs methylation rate.

CONCLUSION

In this study, six key genes that were regulated by HOXA10 were selected, and all of them were enriched in cholesterol synthesis. This finding provided a new insight into the metabolic mechanism of cholesterol in ESC. It also provided a potential treatment strategy for cholesterol metabolism maladjustment in patients with ovarian endometriosis.

Is intracrinology of endometriosis relevant in clinical practice? A systematic review on estrogen metabolism

Endometriosis is a chronic, multifactorial, estrogen-dependent disease. The abnormal endocrine microenvironment of endometriosis lesions is considered a main feature and multiple enzymatic pathways leading to local increased synthesis of estrogens have been identified. However, the relevance of intracrinology in clinical practice is still lacking. Medline, Embase, Scopus database were systematically searched for studies reporting on local estrogens metabolism of endometriotic lesions. The main enzymatic pathways involved in the intracrinology of endometriosis such as aromatase (CYP19A1), 17β-hydroxysteroid dehydrogenase (HSD17B) type 1, type 2 and type 5, steroid sulfatase (STS), estrogen sulfotransferase (SULT1E1) were assessed with a critical perspective on their role in disease endocrine phenotyping, drug resistance and as therapeutic targets. Overall, studies heterogeneity and missing clinical data affect the interpretation of the clinical role of these enzymes. Although the use of some drugs such as aromatase inhibitors has been proposed in clinical practice for two decades, their potential clinical value is still under investigation as well as their modality of administration. A closer look at new, more realistic drug targets is provided and discussed. Altered expression of these key enzymes in the lesions have far reaching implication in the development of new drugs aimed at decreasing local estrogenic activity with a minimal effect on gonadal function; however, given the complexity of the evaluation of the expression of the enzymes, multiple aspects still remains to be clarified.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022311329, identifier CRD42022311329.

The Role of Aromatase Enzyme in Hormone Related Diseases and Plant-Based Aromatase Inhibitors as Therapeutic Regimens

Medicinal plants have a long history of use as food and remedy in traditional and modern societies, as well as have been used as herbal drugs and sources of novel bioactive compounds. They provide a wide array of chemical compounds, many of which can not be synthesized via current synthesis methods. Natural products may provide aromatase inhibitory activity through various pathways and may act clinically effective for treating pathologies associated with excessive aromatase secretion including breast, ovarian and endometrial cancers, endometriosis, uterine fibroid, benign prostatic hyperplasia (BPH), prostate cancer, infertility, and gynecomastia. Recent studies have shown that natural products with aromatase inhibitory activity, could also be good options against secondary recurrence of breast cancer by exhibiting chemopreventive effects. Therefore, screening for new plant-based aromatase inhibitors may provide novel leads for drug discovery and development, particularly with increased clinical efficacy and decreased side effects.

Decreased occurrence of endometriosis in women with Chlamydia trachomatis infection

PROBLEM

Despite abundant reports on the risk role of uterine outflow tract obstruction in endometriosis, information on the occurrence of endometriosis in women with Chlamydia trachomatis infection causing fallopian tube obstruction is unknown. We investigated the role of Chlamydia trachomatis infection with or without fallopian tubal patency in the occurrence of endometriosis.

METHODS

This is a retrospective case-controlled cohort study with 539 women who had laparoscopic surgery for several indications during the period between January, 2003 and June, 2010. Women with ectopic pregnancy, uterine anomaly, chromosomal abnormality, primary amenorrhea, and perimenopausal women were excluded. Endometriosis was diagnosed by laparoscopic inspection and confirmed by histopathology. Tubal patency was diagnosed by HSG or laparoscopic chromopertubation test. Presence of chlamydia infection was examined by RT-PCR and serological test.

RESULTS

Two-hundred and seven women were enrolled. Eighty-six (41.5%) women had chlamydia infection. Tubal patency and occurrence of endometriosis were significantly decreased among women with chlamydia infection comparing to women without it (P = .005 and P = .0008, respectively). Even among women with patent tube, laparoscopic detection of endometriosis was significantly decreased in chlamydia infected comparing to non-infected women (P = .02). Multiple logistic regression model revealed that previous history of chlamydia infection significantly decreased the occurrence of endometriosis, and was independent of age, menstrual status, parity and tubal patency (odds ratio .44; 95% confidence interval .24-.80; P = .007).

CONCLUSION

A decreased occurrence of peritoneal endometriosis was observed in women with Chlamydia trachomatis infection. The possible impairment of retrograde menstrual flow by chlamydia-infected tubal damage may decrease the risk of endometriosis.

Levofloxacin or gonadotropin releasing hormone agonist treatment decreases intrauterine microbial colonization in human endometriosis

OBJECTIVE

We examined the hypothesis that antibiotic treatment with or without gonadotropin releasing hormone agonist (GnRHa) may decrease intrauterine infection with consequent decrease in tissue inflammation, cell proliferation and angiogenesis in human endometriosis.

STUDY DESIGN

This is a prospective non-randomized observational study. Endometrial/endometriotic samples were collected during surgery from 53 women with endometriosis and 47 control women who were treated with levofloxacin (LVFX, 500 mg, once per os) or GnRHa (1.88 mg/IM for 3 months) before surgery. Endometrial samples were analyzed by broad-range polymerase-chain reaction (PCR) amplification of bacteria targeting V5-V6 region of 16S rRNA gene. Immunohistochemical analysis was performed using antibodies against CD138 (Syndecan-1, a marker of plasma cells), CD68 (marker of macrophages), Ki-67 (cell proliferation marker), and CD31 (vascular cells marker).

RESULTS

16S rDNA metagenome assay indicated that treatment with either of LVFX or GnRHa + LVFX significantly decreased some components of major bacterial genera comparing to untreated group. In women with endometriosis, treatment with either of LVFX or GnRHa + LVFX significantly decreased Gardnerella, Prevotella, Acidibactor, Atopobium, Megasphaera, and Bradyrhizobium (p < 0.05 for each) comparing to untreated group. Cochran-Mantel-Haenszel test indicated that occurrence rate of chronic endometritis was significantly decreased after GnRHa + LVFX treatment comparing to GnRHa treatment group (p = 0.041). These findings were coincided with significantly decreased CD68-stained macrophage infiltration, Ki-67- stained cell proliferation and CD31-stained micro-vessel density in endometria and endometriotic lesions with histology proven improvement in the morphological appearance of ovarian endometrioma.

CONCLUSIONS

These findings suggest that clinical administration of a broad-spectrum antibiotic with or without GnRHa may be effective in improving uterine infection with decrease of tissue inflammation, cell proliferation, and angiogenesis in human endometriosis.

Single-cell transcriptomic analysis of endometriosis provides insights into fibroblast fates and immune cell heterogeneity

Background

Endometriosis is an oestrogen-dependent disease with an unclear aetiology and pathogenesis affecting 6–10% of the global female population, predominantly those of reproductive age. Herein, we profile the transcriptomes of approximately 55,000 single cells from three groups including ectopic endometrium, eutopic endometrium from women with endometriosis, and eutopic endometrium from healthy women to create a single-cell transcriptome atlas of endometriosis.

Results

We have identified 9 cell types and performed single-cell analysis of fibroblasts, and determined a potential developmental trajectory associated with endometriosis. We also identified fibroblast subpopulations related to endometriosis development and found that StAR played an important role in this process. Moreover, T cells in endometriosis were less activated or inflammatory with decreased effector CD8 + T cells, while the composition ratio of natural killer cells decreased and the percentage of monocytes/macrophages increased in endometriosis cysts. In addition, the effectiveness of immune cells in endometriosis lesions, eutopic endometrium from women with endometriosis, and eutopic endometrium from healthy women was distinct. Cell–cell interaction analyses highlighted the imbalanced immune environment in endometriosis lesions and immune cells in endometriosis could promote the development of the disease.

Conclusion

Our study provided a systematic characterisation of endometriosis and insights into the aetiology and pathology of endometriosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-021-00637-x.

Endometriosis and polycystic ovary syndrome are diametric disorders

Evolutionary and comparative approaches can yield novel insights into human adaptation and disease. Endometriosis and polycystic ovary syndrome (PCOS) each affect up to 10% of women and significantly reduce the health, fertility, and quality of life of those affected. PCOS and endometriosis have yet to be considered as related to one another, although both conditions involve alterations to prenatal testosterone levels and atypical functioning of the hypothalamic-pituitary-gonadal (HPG) axis. Here, we propose and evaluate the novel hypothesis that endometriosis and PCOS represent extreme and diametric (opposite) outcomes of variation in HPG axis development and activity, with endometriosis mediated in notable part by low prenatal and postnatal testosterone, while PCOS is mediated by high prenatal testosterone. This diametric disorder hypothesis predicts that, for characteristics shaped by the HPG axis, including hormonal profiles, reproductive physiology, life-history traits, and body morphology, women with PCOS and women with endometriosis will manifest opposite phenotypes. To evaluate these predictions, we review and synthesize existing evidence from developmental biology, endocrinology, physiology, life history, and epidemiology. The hypothesis of diametric phenotypes between endometriosis and PCOS is strongly supported across these diverse fields of research. Furthermore, the contrasts between endometriosis and PCOS in humans parallel differences among nonhuman animals in effects of low versus high prenatal testosterone on female reproductive traits. These findings suggest that PCOS and endometriosis represent maladaptive extremes of both female life-history variation and expression of sexually dimorphic female reproductive traits. The diametric disorder hypothesis for endometriosis and PCOS provides novel, unifying, proximate, and evolutionary explanations for endometriosis risk, synthesizes diverse lines of research concerning the two most common female reproductive disorders, and generates future avenues of research for improving the quality of life and health of women.

Effect of combined contraceptive pill on immune cell of ovarian endometriotic tissue

BACKGROUND

Dysregulation of immune response is associated with development of endometriosis. The study aim was to evaluate effect of combined oral contraceptive pills (COCs) consisting of ethinyl estradiol (EE) and desogestrel on the expression of macrophage, natural killer cells, and regulatory T cells of ovarian endometriotic cysts.

METHODS

Endometriotic cyst wall tissues were collected from women with endometriosis who were treated (n = 22) with COCs (one table per day of EE 0.03 mg and desogestrel 0.15 mg administered for 28 to 35 days before surgery) or untreated (n = 22). The tissues were collected from endometriotic cyst wall during laparoscopic or laparotomy ovarian cystectomy. Immunohistochemistry for anti-CD68, anti-CD56, and anti-forkhead-winged helix transcription factor (FoxP3), a marker for macrophages, natural killer cells, and regulatory T cells, respectively, were investigated.

RESULTS

The median (interquartile range [IQR]) number of anti-CD68 positive cells in the COC group was significantly lower than in the untreated group (12.7; 4.9-19.3) versus 45.7 (26.0-70.7), p < 0.001). Tissue infiltration of anti-CD56 positive cells in endometriotic cyst was significantly higher after the treatment when compared with tissue from untreated group (42.9, 27.4-68.9 versus 25.3 (14.1-37.3; p = 0.009). The number of regulatory T cells was also significantly increased in the COC group (6.3, 2.8-15.5) versus 0 (0-1.8; p < 0.001).

CONCLUSIONS

The effects of COC, containing EE 0.30 mg with desogestrel 0.15 mg, on the immune system was demonstrated by a significant decrease in the number of macrophages and an increase in natural killer and regulatory T cells.

Metformin, the Rise of a New Medical Therapy for Endometriosis? A Systematic Review of the Literature

Medical treatments for endometriosis aim to control pain symptoms and stop progression of endometriotic lesions. However, their adverse effects and their contraceptive effect in women who desire pregnancy, limit their long terms use. Although there is only one study investigating the effects of metformin on women with endometriosis, metformin seems to have a unique therapeutic potential. It may be a helpful anti-inflammatory and antiproliferative agent in the treatment of endometriosis. As such metformin may be more beneficial thanks to the lack of serious side effects.

Altered Composition of Microbiota in Women with Ovarian Endometrioma: Microbiome Analyses of Extracellular Vesicles in the Peritoneal Fluid

Human microbiota refers to living microorganisms which colonize our body and crucially contribute to the metabolism of nutrients and various physiologic functions. According to recently accumulated evidence, human microbiota dysbiosis in the genital tract or pelvic cavity could be involved in the pathogenesis and/or pathophysiology of endometriosis. We aimed to investigate whether the composition of microbiome is altered in the peritoneal fluid in women with endometriosis. We recruited 45 women with histological evidence of ovarian endometrioma and 45 surgical controls without endometriosis. Following the isolation of extracellular vesicles from peritoneal fluid samples from women with and without endometriosis, bacterial genomic DNA was sequenced using next-generation sequencing of the 16S rDNA V3–V4 regions. Diversity analysis showed significant differences in the microbial community at phylum, class, order, family, and genus levels between the two groups. The abundance of Acinetobacter, Pseudomonas, Streptococcus, and Enhydrobacter significantly increased while the abundance of Propionibacterium, Actinomyces, and Rothia significantly decreased in the endometriosis group compared with those in the control group (p < 0.05). These findings strongly suggest that microbiome composition is altered in the peritoneal environment in women with endometriosis. Further studies are necessary to verify whether dysbiosis itself can cause establishment and/or progression of endometriosis.

In the mouse, prostaglandin D2 signalling protects the endometrium against adenomyosis

Adenomyosis is characterised by epithelial gland and mesenchymal stroma invasion of the uterine myometrium. Adenomyosis is an oestrogen-dependent gynaecological disease in which a number of factors, such as inflammatory molecules, prostaglandins (PGs), angiogenic factors, cell proliferation and extracellular matrix remodelling proteins, also play a role as key disease mediators. In this study, we used mice lacking both lipocalin and hematopoietic-PG D synthase (L- and H-Pgds) genes in which PGD2 is not produced to elucidate PGD2 roles in the uterus. Gene expression studied by real-time PCR and hormone dosages performed by ELISA or liquid chromatography tandem mass spectroscopy in mouse uterus samples showed that components of the PGD2 signalling pathway, both PGDS and PGD2-receptors, are expressed in the mouse endometrium throughout the oestrus cycle with some differences among uterine compartments. We showed that PGE2 production and the steroidogenic pathway are dysregulated in the absence of PGD2. Histological analysis of L/H-Pgds-/- uteri, and immunohistochemistry and immunofluorescence analyses of proliferation (Ki67), endothelial cell (CD31), epithelial cell (pan-cytokeratin), myofibroblast (α-SMA) and mesenchymal cell (vimentin) markers, identify that 6-month-old L/H-Pgds-/- animals developed adenomyotic lesions, and that disease severity increased with age. In conclusion, this study suggests that the PGD2 pathway has major roles in the uterus by protecting the endometrium against adenomyosis development. Additional experiments, using for instance transcriptomic approaches, are necessary to fully determine the molecular mechanisms that lead to adenomyosis in L/H-Pgds-/- mice and to confirm whether this strain is an appropriate model for studying the human disease.

Endometriosis is a chronic systemic disease: clinical challenges and novel innovations

Endometriosis is a common disease affecting 5-10% of women of reproductive age globally. However, despite its prevalence, diagnosis is typically delayed by years, misdiagnosis is common, and delivery of effective therapy is prolonged. Identification and prompt treatment of endometriosis are essential and facilitated by accurate clinical diagnosis. Endometriosis is classically defined as a chronic, gynaecological disease characterised by endometrial-like tissue present outside of the uterus and is thought to arise by retrograde menstruation. However, this description is outdated and no longer reflects the true scope and manifestations of the disease. The clinical presentation is varied, the presence of pelvic lesions is heterogeneous, and the manifestations of the disease outside of the female reproductive tract remain poorly understood. Endometriosis is now considered a systemic disease rather than a disease predominantly affecting the pelvis. Endometriosis affects metabolism in liver and adipose tissue, leads to systemic inflammation, and alters gene expression in the brain that causes pain sensitisation and mood disorders. The full effect of the disease is not fully recognised and goes far beyond the pelvis. Recognition of the full scope of the disease will facilitate clinical diagnosis and allow for more comprehensive treatment than currently available. Progestins and low-dose oral contraceptives are unsuccessful in a third of symptomatic women globally, probably as a result of progesterone resistance. Oral gonadotropin-releasing hormone (GnRH) antagonists constitute an effective and tolerable therapeutic alternative when first-line medications do not work. The development of GnRH antagonists has resulted in oral drugs that have fewer side-effects than other therapies and has allowed for rapid movement between treatments to optimise and personalise endometriosis care. In this Review, we discuss the latest understanding of endometriosis as a systemic disease with multiple manifestations outside the parameters of classic gynaecological disease.

Human BM-MSC secretome enhances human granulosa cell proliferation and steroidogenesis and restores ovarian function in primary ovarian insufficiency mouse model

Primary ovarian insufficiency (POI) is defined as the loss of ovarian function before 40 years of age. It clinically manifests as amenorrhea, infertility, and signs of estrogen insufficiency. POI is frequently induced by chemotherapy. Gonadotoxic chemotherapy reagents damage granulosa cells, which are essential for follicular function and development. Our recently published studies demonstrated that intraovarian transplantation of human mesenchymal stem cells (hMSCs) can restore fertility in a chemotherapy-induced POI mouse model. However, the regenerative mechanism underlying the hMSC effect in POI mice is not fully understood. Here, we report that the hMSC secretome increased the proliferation of human granulosa cells (HGrC1). We showed by FACS analysis that treatment of HGrC1 cells with hMSC-conditioned media (hMSC CM) stimulates cellular proliferation. We also demonstrated that the expression of steroidogenic enzymes involved in the production of estrogen, CYP19A1 and StAR, are significantly elevated in hMSC CM-treated HGrC1 cells. Our data suggest that hMSC CM stimulates granulosa cell proliferation and function, which may explain the therapeutic effect of hMSCs in our chemotherapy-induced POI animal model. Our findings indicate that the hMSC secretome may be a novel treatment approach for restoring granulosa cell and ovarian function in patients with POI.

The hormonal control of the uterus of the bat Myotis nigricans during its different reproductive phases: emphasis on progesterone and estradiol

Myotis nigricans is a species of bat from the Vespertilionidae family that is endemic of the Neotropical region. Its insectivorous feeding habit plus its large range of prey species, great geographical dispersion, wide colonies, and anthropomorphized behavior make this species an important ecological agent that acts in the control of nocturnal insects. Reproductively, M. nigricans presents geographic variations, having different patterns of reproduction according to its geographical location. Despite these extremely interesting characteristics, no more detailed study of the hormonal control of the reproduction of this species has been conducted. Therefore, the aim of the present study was to evaluate the variations in serum hormone concentrations and in uterine hormonal control of this bat during its different reproductive phases. Twenty adult females were collected, divided into four (4) sample groups, according to the reproductive status (nonreproductive, initial, and advanced pregnancy and lactating), and submitted to hormone dosage and immunohistochemical analyses. The results demonstrated that the uterus of M. nigricans is strongly regulated by the interaction/cross-talk between serum concentrations of estradiol (E2) and progesterone with their respective hormone receptors. Significant increases in the concentration of E2 and progesterone are needed to regulate the early pregnancy. The persistence of the corpus luteum throughout pregnancy is necessary, since its placenta does not express aromatase. The expressions of ERα and PR appear to be synchronized in order to coordinate a large portion of the processes that occur inside the uterus of M. nigricans during pregnancy and lactation.

Markers of Local and Systemic Estrogen Metabolism in Endometriosis

Estrogen metabolites (EMs) can work independently from their parent hormones. We hypothesize that in endometriosis, estrogen is metabolized preferentially along hormonally active pathways. We recruited 62 women with endometriosis (proven laparoscopically and histologically) and 52 control women (normal findings with laparoscopy) among patients undergoing surgery for pelvic pain and/or infertility during the proliferative phase of the menstrual cycle. Urinary samples were collected preoperatively. Biopsies from eutopic endometrium of control women and women with endometriosis were collected during surgery. EMs in urine and endometrial tissues were extracted and determined using Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry (LC-ESI-MS/MS). These included: 2-hydroxyestrone (2OHE1), 16-α hydroxyestrone (16α-OHE1), 2OHE1/16α-OHE1 ratio, 4-hydroxyestrone (4OHE1), 2-hydroxyestradiol (2OHE2), and 4-hydroxyestradiol (4OHE2). Eutopic endometrium of endometriosis patients, as compared to control endometrium, contained significantly higher level of 4OHE1 (0.03 (IQR: 0.03-0.265) versus 0.03 (IQR: 0.03-0.03) μg/g, respectively, P = 0.005), 2-OHE2 (0.241 (IQR: 0.1-0.960) versus 0.1 (IQR: 0.1-0.1) μg/g, respectively, P < 0.001), and 4-OHE2 (0.225 (IQR: 0.22-1.29) versus 0.0.2 (IQR: 0.2-0.2) μg/g, respectively, P < 0.001). Only 2OHE1 showed higher concentration in urine of women with endometriosis than controls (9.9 (IQR: 3.64-14.88) versus 4.5 (IQR: 1.37-17.00) μg/mg creatinine, respectively, P = 0.042). Eutopic endometrium of women with endometriosis metabolizes estrogen preferentially to the biologically active 2OHE2, and potentially genotoxic 4OHE1 and 4OHE2 metabolites. This contributes to further understanding of endometriosis etiology, its link to ovarian cancer, and could help identifying an endometrial biomarker of the disease.

Plants as source of new therapies for endometriosis: a review of preclinical and clinical studies

BACKGROUND

Given the disadvantages and limitations of current endometriosis therapy, there is a progressive increase in studies focusing on plant-derived agents as a natural treatment option with the intention of achieving high efficiency, avoiding adverse effects and preserving the chance for successful pregnancy. The heterogeneity of these studies in terms of evaluated agents, applied approaches and outcomes illustrates the need for an up-to-date summary and critical view on this rapidly growing field in endometriosis research.

OBJECTIVE AND RATIONALE

This review provides a comprehensive overview of plant-derived agents and natural treatment strategies that are under preclinical or clinical investigation and critically evaluates their potential for future endometriosis therapy.

SEARCH METHODS

An English language PubMed literature search was performed using variations of the terms 'endometriosis', 'natural therapy', 'herb/herbal', 'plant', 'flavonoid', 'polyphenol', 'phytochemical', 'bioactive', 'Kampo' and 'Chinese medicine'. It included both animal and human studies. Moreover, the Clinicaltrials.gov database was searched with the term 'endometriosis' for clinical trials on plant-derived agents. No restriction was set for the publication date.

OUTCOMES

Natural therapies can be assigned to three categories: (i) herbal extracts, (ii) specific plant-derived bioactive compounds and (iii) Chinese herbal medicine (CHM). Agents of the first category have been shown to exert anti-proliferative, anti-inflammatory, anti-angiogenic and anti-oxidant effects on endometrial cells and endometriotic lesions. However, the existing evidence supporting their use in endometriosis therapy is quite limited. The most studied specific plant-derived bioactive compounds are resveratrol, epigallocatechin-3-gallate, curcumin, puerarin, ginsenosides, xanthohumol, 4-hydroxybenzyl alcohol, quercetin, apigenin, carnosic acid, rosmarinic acid, wogonin, baicalein, parthenolide, andrographolide and cannabinoids, with solid evidence about their inhibitory activity in experimental endometriosis models. Their mechanisms of action include pleiotropic effects on known signalling effectors: oestrogen receptor-α, cyclooxygenase-2, interleukin-1 and -6, tumour necrosis factor-α, intercellular adhesion molecule-1, vascular endothelial growth factor, nuclear factor-kappa B, matrix metalloproteinases as well as reactive oxygen species (ROS) and apoptosis-related proteins. Numerous studies suggest that treatment with CHM is a good choice for endometriosis management. Even under clinical conditions, this approach has already been shown to decrease the size of endometriotic lesions, alleviate chronic pelvic pain and reduce postoperative recurrence rates.

WIDER IMPLICATIONS

The necessity to manage endometriosis as a chronic disease highlights the importance of identifying novel and affordable long-term safety therapeutics. For this purpose, natural plant-derived agents represent promising candidates. Many of these agents exhibit a pleiotropic action profile, which simultaneously inhibits fundamental processes in the pathogenesis of endometriosis, such as proliferation, inflammation, ROS formation and angiogenesis. Hence, their inclusion into multimodal treatment concepts may essentially contribute to increase the therapeutic efficiency and reduce the side effects of future endometriosis therapy.

Free large sized intra-abdominal endometrioma in a postmenopausal woman: a case report

BACKGROUND

Endometriosis is an estrogen-dependent disease defined by the presence of endometrial glands and stroma out of the uterine cavity. Its prevalence is estimated to be 2-10% in reproductive aged women. Endometriosis occurrence is estimated to be 2.55% in postmenopausal patients due to the decreased levels of estrogen. Endometriosis can present in three different forms: superficial peritoneal implants, ovarian endometriomas, and deep infiltrating endometriosis. Ovarian endometriomas are the most common form of endometriosis. Even though endometriomas have been encountered in various localizations, a free abdominal endometrioma was only reported once in a premenopausal patient. Here, we are reporting the first case of a free large endometrioma in a postmenopausal patient.

CASE PRESENTATION

A 67-year-old woman presented to the emergency department at our university hospital complaining of constipation and right flank pain. She suffered from uncontrolled primary hypertension and type 2 diabetes mellitus. On presentation, she was afebrile, hypertensive, and tachycardic. An abdominal CT scan revealed a large cystic mass measuring 17 × 26 cm in the anterior-posterior and transverse diameters respectively. The cyst caused bowel obstruction and right sided hydronephrosis. The patient underwent laparotomy and during the surgical exploration a large abdominal cyst adhered to the greater omentum was found. The cyst received plenteous blood supply from the greater omentum. The uterus and both ovaries were completely normal and didn't have any connection to the cyst. An en-bloc cystectomy was performed successfully. The final histopathology report confirmed an abdominal endometrioma. The patient had an uneventful postoperative recovery.

CONCLUSIONS

Endometriomas might reach large sizes regardless of their location or the patient's age. The close relation of free abdominal endometriomas with the greater omentum suggests that these were developed from endometriotic omental implants. Endometrioma is rare in postmenopausal women. However, it should be considered as a possible differential diagnosis at any age.

Pretreatment with a gonadotropin-releasing hormone agonist and an aromatase inhibitor may improve outcomes in in vitro fertilization cycles of women with stage I-II endometriosis

OBJECTIVE

To determine whether 2 months of pretreatment with 5 mg of letrozole daily plus leuprolide acetate at 3.75 mg monthly in women with laparoscopically confirmed American Society of Reproductive Medicine stage I-II endometriosis improves in vitro fertilization (IVF) outcomes.

DESIGN

Prospective cohort study.

SETTING

University-affiliated tertiary hospital.

PATIENT(S)

Women with laparoscopically confirmed endometriosis treated in the period from 2012 to 2016.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Primary outcomes: clinical pregnancy and live-birth rate; secondary outcomes: stimulation parameters and pregnancy.

RESULT(S)

A total of 68 patients were included in the final analysis. Thirty-six women received a gonadotropin-releasing hormone (GnRH) agonist and an aromatase inhibitor (AI), and 32 women received a GnRH agonist alone. The women did not differ in mean age, antral follicle count, basal serum level of follicle-stimulating hormone, or previous pregnancies. The stimulation parameters were similar between both groups: gonadotropin dose, number of collected oocytes, number of blastocysts. All women underwent a single blastocyst transfer. The grade of embryos transferred did not differ. Clinical pregnancy (24 [66.7%] vs. 13 [40.6%]) and live-birth (22 [61.1%] vs 10 [31.3%]) rates improved with aromatase inhibitor added to the GnRH agonist treatment versus a GnRH agonist alone.

CONCLUSION(S)

In this study, we present the first comparison in the medical literature comparing IVF outcomes in women with minimal and mild endometriosis pretreated with a GnRH agonist with or without an AI. This prospective cohort study suggests that combining these two treatment modalities which work at different sites may improve pregnancy outcomes with IVF treatment.

Steroid hormones regulate genome-wide epigenetic programming and gene transcription in human endometrial cells with marked aberrancies in endometriosis

Programmed cellular responses to cycling ovarian-derived steroid hormones are central to normal endometrial function. Abnormalities therein, as in the estrogen-dependent, progesterone-"resistant" disorder, endometriosis, predispose to infertility and poor pregnancy outcomes. The endometrial stromal fibroblast (eSF) is a master regulator of pregnancy success. However, the complex hormone-epigenome-transcriptome interplay in eSF by each individual steroid hormone, estradiol (E2) and/or progesterone (P4), under physiologic and pathophysiologic conditions, is poorly understood and was investigated herein. Genome-wide analysis in normal, early and late stage eutopic eSF revealed: i) In contrast to P4, E2 extensively affected the eSF DNA methylome and transcriptome. Importantly, E2 resulted in a more open versus closed chromatin, confirmed by histone modification analysis. Combined E2 with P4 affected a totally different landscape than E2 or P4 alone. ii) P4 responses were aberrant in early and late stage endometriosis, and mapping differentially methylated CpG sites with progesterone receptor targets from the literature revealed different but not decreased P4-targets, leading to question the P4-"resistant" phenotype in endometriosis. Interestingly, an aberrant E2-response was noted in eSF from endometriosis women; iii) Steroid hormones affected specific genomic contexts and locations, significantly enriching enhancers and intergenic regions and minimally involving proximal promoters and CpG islands, regardless of hormone type and eSF disease state. iv) In eSF from women with endometriosis, aberrant hormone-induced methylation signatures were mainly due to existing DNA methylation marks prior to hormone treatments and involved known endometriosis genes and pathways. v) Distinct DNA methylation and transcriptomic signatures revealed early and late stage endometriosis comprise unique disease subtypes. Taken together, the data herein, for the first time, provide significant insight into the hormone-epigenome-transcriptome interplay of each steroid hormone in normal eSF, and aberrant E2 response, distinct disease subtypes, and pre-existing epigenetic aberrancies in the setting of endometriosis, provide mechanistic insights into how endometriosis affects endometrial function/dysfunction.

Pathophysiological implications of hypoxia in human diseases

Oxygen is essentially required by most eukaryotic organisms as a scavenger to remove harmful electron and hydrogen ions or as a critical substrate to ensure the proper execution of enzymatic reactions. All nucleated cells can sense oxygen concentration and respond to reduced oxygen availability (hypoxia). When oxygen delivery is disrupted or reduced, the organisms will develop numerous adaptive mechanisms to facilitate cells survived in the hypoxic condition. Normally, such hypoxic response will cease when oxygen level is restored. However, the situation becomes complicated if hypoxic stress persists (chronic hypoxia) or cyclic normoxia-hypoxia phenomenon occurs (intermittent hypoxia). A series of chain reaction-like gene expression cascade, termed hypoxia-mediated gene regulatory network, will be initiated under such prolonged or intermittent hypoxic conditions and subsequently leads to alteration of cellular function and/or behaviors. As a result, irreversible processes occur that may cause physiological disorder or even pathological consequences. A growing body of evidence implicates that hypoxia plays critical roles in the pathogenesis of major causes of mortality including cancer, myocardial ischemia, metabolic diseases, and chronic heart and kidney diseases, and in reproductive diseases such as preeclampsia and endometriosis. This review article will summarize current understandings regarding the molecular mechanism of hypoxia in these common and important diseases.

Microbiota composition and distribution along the female reproductive tract of women with endometriosis

Endometriosis (EMS) is a multifactorial disease that affects 10%-15% women of reproductive age and is associated with chronic pelvic pain and infertility. The pathogenesis of EMS has not been consistently explained until now. In this study, we involved 36 endometriosis patients and 14 control subjects who performed laparoscopic surgery due to gynecological benign tumor. The samples from lower third of vagina (CL), posterior vaginal fornix (CU), cervical mucus (CV), endometrium (ET) and peritoneal fluid (PF), were collected and sequenced by 16S rRNA amplicon. The continuous change of the microbiota distribution was identified along the reproductive tract. The flora in lower reproductive tract (CL, CU) were dominated by Lactobacillus. Significant difference of the community diversity began showing in the CV of EMS patients and gradually increased upward the reproductive tract. It indicates the microbiota in cervical samples is expected to be an indicator for the risk of EMS. This study also highlights the decreasing of Lactobacillus in vaginal flora and the increasing of signature Operational Taxonomic Units (OTUs) in transaction zone (CV) and upper reproductive tract (ET, PF) of EMS patients, which reflect the alteration of microbial community associated with EMS, participation of specific colonized bacteria in the EMS pathogenesis and relationship between microbiota and development of disease.

Progesterone's role in deep infiltrating endometriosis: Progesterone receptor and estrogen metabolism enzymes expression and physiological changes in primary endometrial stromal cell culture

To study progesterone signaling activation, we measured changes in extracellular pH as a reflection of Na+/H+ exchange (NHE) using a cytosensor microphysiometer and assessed progesterone receptor (PR) and estrogen metabolism enzymes mRNA expression in cultured endometrial cells from women with deep infiltrating endometriosis and healthy controls using real-time quantitative PCR. This study was conducted at a University hospital and included patients with and without deep infiltrating endometriosis (DIE). Primary endometrial stromal cells (ECs) from women with DIE and controls were treated with 17β-estradiol and progesterone prior to microphysiometer measurements and qPCR evaluations. Decreased progesterone responsiveness and decreased total nuclear PR and HSD17B1 mRNA expression were observed in cultured ECs from women with deep infiltrating endometriosis relative to those from control samples before and after hormone treatment. These cells also showed increased 17β-hydroxysteroid dehydrogenases types 2 (HSD17B2) relative to control group and increased expression of aromatase (CYP19) after exposure to progesterone. These physiological and expression patterns observed in ECs cultures from women with DIE reinforces previous findings in the literature supporting the progesterone resistance hypothesis in the pathogenesis of endometriosis.

An assessment of the multifactorial profile of steroid-metabolizing enzymes and steroid receptors in the eutopic endometrium during moderate to severe ovarian endometriosis

BACKGROUND

Previous studies of expression profiles of major endometrial effectors of steroid physiology in endometriosis have yielded markedly conflicting conclusions, presumably because the relative effects of type of endometriosis, fertility history and menstrual cycle phases on the measured variables were not considered. In the present study, endometrial mRNA and protein levels of several effectors of steroid biosynthesis and action in patients with stage III-IV ovarian endometriosis (OE) with known fertility and menstrual cycle histories were compared with the levels in control endometrium to test this concept.

METHODS

Endometrial samples were collected from patients without endometriosis (n = 32) or OE stages III-IV (n = 52) with known fertility and cycle histories. qRT-PCR and immunoblotting experiments were performed to measure levels of NR5A1, STAR, CYP19A1, HSD17Bs, ESRs and PGR transcripts and proteins, respectively. Tissue concentrations of steroids (P4, T, E1 and E2) were measured using ELISAs.

RESULTS

The levels of expression of aromatase and ERβ were lower (P < 0.0001) and 17β-HSD1 (P < 0.0001) and PRA (P < 0.01) were higher in OE endometrium. Lower aromatase levels and higher 17β-HSD1 levels were detected in fertile (aromatase: P < 0.05; 17β-HSD1: P < 0.0001) and infertile (aromatase: P < 0.0001; 17β-HSD1: P < 0.0001) OE endometrium than in the matched control tissues. Both proliferative (PP) and secretory (SP) phase OE samples expressed aromatase (P < 0.0001) and ERβ (PP: P < 0.001; SP: P < 0.01) at lower levels and 17β-HSD1 (P < 0.0001) and PRA (PP: P < 0.01; SP: P < 0.0001) at higher levels than matched controls. Higher 17β-HSD1 (P < 0.01) and E2 (P < 0.05) levels and a lower (P < 0.01) PRB/PRA ratio was observed in infertile secretory phase OE endometrium than in control.

CONCLUSIONS

We report that dysregulated expression of 17β-HSD1 and PGR resulting in hyperestrogenism and progesterone resistance during the secretory phase of the menstrual cycle, rather than an anomaly in aromatase expression, was the hallmark of eutopic endometrium from infertile OE patients. Furthermore, the results provide proof of concept that the fertility and menstrual cycle histories exerted relatively different effects on steroid physiology in the endometrium from OE patients compared with the control subjects.

Epidemiological aspects of the outcomes from the treatment of endometriosis: Experience from two different geographical areas

The purpose of the present study was two-fold: First to review the epidemiological aspects of the experience on the surgical outcomes via laparotomy or laparoscopy, as regards endometriosis from two different academic institutions and, second, to illustrate potential differences in two different geographical areas, New Haven (US) and Greece. This retrospective study included 1,200 patients (15–80 years of age) treated via laparotomy or laparoscopy, at two different institutions, for endometriosis, between 1990 and 2017. Data were collected and analyzed from medical and pathological reports. The statistical methods used included the Student's t-test and χ² test, as well as the Mann-Whitney U test. A total of 600 women from Yale University and 600 women from Greece participated in this study. Endometrioma was confirmed in 359 (29.9%) cases. Women were compatible in terms of the site of endometriomas. Left-sided cysts were observed (P<0.001) significantly more often compared with right-sided cysts in both groups. The two groups of patients had similar rates of endometriosis stages. A statistically significant positive association (P<0.001) was found for the co-existence of benign gynecological tumors (apart from endometrioma), endometriosis-associated ovarian cancer and for post-menopausal endometriosis in women with endometriosis from Greece. Moreover, similar results were observed as regards endometriosis following in utero exposure to diethylstilbestrol (DES), non-Hodgkin's lymphoma, endometriosis-associated Lyme disease, human immuno-deficiency virus (HIV), melanoma and endometriosis in adolescents, between the two groups. To conclude, the two populations exhibited similar results as regards the surgical outcomes of endometriosis laparoscopic or open surgery. Endometriosis represents a multifactorial entity that depends on complex interactions of hormonal, genetic, immunological and environmental factors. Gynecologists should be aware that there is an association between endometriosis and cancerous diseases. It is thus suggested that the presence of comorbidities in women with endometriosis.

Effect of local aromatase inhibition in endometriosis using a new chick embryo chorioallantoic membrane model

Endometriosis is an oestrogen‐dependent, inflammation‐driven gynaecologic disorder causing severe disability. Endometriosis implants are characterized by unbalanced local oestrogen metabolism leading to hyperoestrogenism and aromatase up‐regulation is one of main mechanism involved. Aromatase inhibitors such as letrozole or anastrozole use in young women are associated with severely side effects limiting their long‐term clinical use. An endometriosis‐targeted inhibition of local aromatase could be a viable alternative, although the role of the local inhibition of this enzyme is still unclear. Using a new chick embryo allantoic membrane (CAM) model incorporating xenografted human endometriosis cyst, we showed that topical treatment with anastrozole reduced lesion size, although oestrogens produced by CAM female embryo blunted this effect. Xenografted human endometriosis CAM is a new efficient model for the screening of new drugs targeting endometriosis tissue.

Endometriosis and ovarian cancer: Their association and relationship

Objectives

To study endometriosis-associated borderline or malignant ovarian epithelial tumors by analyzing their differential clinical features, as well as the histological pattern, survival and immunohistochemical data compared with those without associated endometriosis.

Study design

Setting: Hospital Marina Baixa and San Juan University Hospital, Alicante, Spain. This retrospective study included clinical and pathological data from 36 operated cases with endometriosis-associated ovarian epithelial tumors and 305 cases of ovarian epithelial tumors without endometriosis, including borderline and invasive tumors. We also studied hormonal receptors and p53 protein expression in 13 cases with endometriosis-associated endometrioid and clear cell tumors, and report two cases with histologically-confirmed previous endometriosis.

Results

Associated endometriosis was observed in 10.5% of patients with borderline or invasive ovarian epithelial tumor, 53% of those with endometrioid, and 22% with clear cell tumors. Patients with endometriosis-associated ovarian epithelial tumors were younger, had lower parity, were more frequently premenopausal, had a lower tumor stage or were borderline, and in general had better prognosis and longer survival, although they also more frequently had an associated endometrial carcinoma. Associated endometriosis and endometrioid tumors were generally estrogen-receptor positive, whereas they were negative in the clear cell tumor component. p53 protein positivity was generally observed in clear cell tumors and in associated endometriosis. Two reported cases with previous, known endometriosis were followed in their evolution to borderline endometrioid carcinoma and clear cell carcinoma, respectively.

Conclusions

Our results and review of the literature suggest that the association of ovarian epithelial tumors and endometriosis is a factor for good prognosis for ovarian cancer and that this association might correspond in many cases to an intermediate stage in the development of endometriosis to endometrioid, clear cell, or other invasive carcinomas.

Keeping an Eye on Perimenopausal and Postmenopausal Endometriosis

Introduction: We aimed to describe and review the epidemiological aspect of the disease pattern of a series of perimenopausal and postmenopausal women with a histology confirmation of endometriosis. Material and Methods: We retrospectively examined the clinical records of 184 perimenopausal and 46 postmenopausal women with endometriosis. Data were collected and analyzed from 1100 patients' charts with confirmed endometriosis and involved cases from two different geographical areas, New Haven (US) and Greece. The statistical methods included ײ and the Mann-Whitney U test. In the perimenopausal group (age 45⁻54 years), there were 184 patients (16.7%) and the postmenopausal group (55⁻80 years) had 46 (4.2%). The average age of diagnosis was (49 ± 2.3) and (61.2 ± 5.1), respectively (p < 0.01). Results: Advanced endometriosis was more aggressive in the perimenopausal group (p < 0.05); in the same group, we observed a higher left-sided predisposition of endometriosis in comparison with the right side (p < 0.01). Endometrioma was the most common gynecological condition among patients with perimenopausal endometriosis in relation to the postmenopausal group (p < 0.001). Additionally, we found uterine leiomyomata more prominent in the perimenopausal group (p < 0.05). In contrast, adenomyosis was found higher in postmenopausal patients (p < 0.05); further, 24 cases with dry eye we observed. Conclusions: Postmenopausal endometriosis is an important underestimated condition. Although the reported situation is not common, various clinicopathological characteristics were observed in both groups. Clinicians should be aware that there is a correlation between endometriosis and endometriosis-associated ovarian cancer in perimenopausal and postmenopausal age.

Therapeutic Approaches of Resveratrol on Endometriosis via Anti-Inflammatory and Anti-Angiogenic Pathways

Endometriosis represents a severe gynecological pathology, defined by implantation of endometrial glands and stroma outside the uterine cavity. This pathology affects almost 15% of women during reproductive age and has a wide range of consequences. In affected women, infertility has a 30% rate of prevalence and endometriosis implants increase the risk of ovarian cancer. Despite long periods of studies and investigations, the etiology and pathogenesis of this disease still remain not fully understood. Initially, endometriosis was related to retrograde menstruation, but new theories have been launched, suggesting that chronic inflammation can influence the development of endometriosis because inflammatory mediators have been identified elevated in patients with endometriosis, specifically in the peritoneal fluid. The importance of dietary phytochemicals and their effect on different inflammatory diseases have been highlighted, and nowadays more and more studies are focused on the analysis of nutraceuticals. Resveratrol is a phytoestrogen, a natural polyphenolic compound with antiproliferative and anti-inflammatory actions, found in many dietary sources such as grapes, wine, peanuts, soy, berries, and stilbenes. Resveratrol possesses a significant anti-inflammatory effect via inhibition of prostaglandin synthesis and it has been proved that resveratrol can exhibit apoptosis-inducing activities. From the studies reviewed in this paper, it is clear that the anti-inflammatory effect of this natural compound can contribute to the prevention of endometriosis, this phenolic compound now being considered a new innovative drug in the prevention and treatment of this disease.

Hypoxia: The force of endometriosis

AIM

Summarize recent findings of how hypoxia regulates numerous important processes to facilitate the implantation, proliferation and progression of ectopic endometriotic lesions.

METHODS

Most up-to-date evidences about how hypoxia contributes to the disease pathogenesis of endometriosis and potential therapeutic approaches were collected by conducting a comprehensive search of medical literature electronic databases. Quality of data was analyzed by experienced experts including gynecologist and basic scientists.

RESULTS

Uterus is a highly vascularized organ, which makes endometrial cells constantly expose to high concentration of oxygen. When endometrial tissues shed off from the eutopic uterus and retrograde to the peritoneal cavity, they face severe hypoxic stress. Even with successful implantation to ovaries or peritoneum, the hypoxic stress remains as a critical issue because endometrial cells are used to live in the well-oxygenated environment. Under the hypoxia condition, cells undergo epigenetic modulation and evolve several survival processes including steroidogenesis, angiogenesis, inflammation and metabolic switch. The complex gene regulatory network driven by hypoxia ensures endometriotic cells can survive under the hostile peritoneal microenvironment.

CONCLUSION

Hypoxia plays critical roles in promoting pathological processes to facilitate the development of endometriosis. Targeting hypoxia-mediated gene network represents an alternative approach for the treatment of endometriosis.

Endometrial Intracrinology: Oestrogens, Androgens and Endometrial Disorders

Peripheral tissue metabolism of steroids (intracrinology) is now accepted as a key way in which tissues, such as the endometrium, can utilise inactive steroids present in the blood to respond to local physiological demands and 'fine-tune' the activation or inhibition of steroid hormone receptor-dependent processes. Expression of enzymes that play a critical role in the activation and inactivation of bioactive oestrogens (E1, E2) and androgens (A4, T, DHT), as well as expression of steroid hormone receptors, has been detected in endometrial tissues and cells recovered during the menstrual cycle. There is robust evidence that increased expression of aromatase is important for creating a local microenvironment that can support a pregnancy. Measurement of intra-tissue concentrations of steroids using liquid chromatography⁻tandem mass spectrometry has been important in advancing our understanding of a role for androgens in the endometrium, acting both as active ligands for the androgen receptor and as substrates for oestrogen biosynthesis. The emergence of intracrinology, associated with disordered expression of key enzymes such as aromatase, in the aetiology of common women's health disorders such as endometriosis and endometrial cancer has prompted renewed interest in the development of drugs targeting these pathways, opening up new opportunities for targeted therapies and precision medicine.