Association between KRAS and PIK3CA Mutations and Progesterone Resistance in Endometriotic Epithelial Cell Line.

Although endometriosis is a benign disease, it is associated with cancer-related gene mutations, such as KRAS or PIK3CA. Endometriosis is associated with elevated levels of inflammatory factors that cause severe pain. In a previous study, we demonstrated that KRAS or PIK3CA mutations are associated with the activation of cell proliferation, migration, and invasion in a patient-derived immortalized endometriotic cell line, HMOsisEC10. In this study, we investigated the effects of these mutations on progesterone resistance. Since the HMOsisEC10 had suppressed progesterone receptor (PR) expression, we transduced PR-B to HMOsisEc10 cell lines including KRAS mutant and PIK3CA mutant cell lines. We conducted a migration assay, invasion assay, and MTT assay using dienogest and medroxyprogestrone acetate. All cell lines showed progesterone sensitivity with or without mutations. Regarding inflammatory factors, real-time quantitative RT-PCR revealed that the KRAS mutation cell line exhibited no suppression of Cox-2 and mPGES-1 on progesterone treatment, whereas IL-6, MCP-1, VEGF, and CYP19A1 were significantly suppressed by progesterone in both mutated cell lines. Our results suggest that KRAS mutation and PIK3CA mutation in endometriotic cells may not be associated with progesterone resistance in terms of aggressiveness. However, KRAS mutations may be associated with progesterone resistance in the context of pain.

The adenomyosis/endometriosis IVF patient - call for clinical focus.

Endometriosis and adenomyosis are distinct clinical conditions that carry the same pathophysiological features. In recent years the clinical focus on assisted reproductive technology patients with either condition (E/A) has increased, in the recognition that this subgroup of patients might need special attention to obtain reproductive success. Endometriosis and adenomyosis are characterized by a disruption of progesterone and oestrogen signalling pathways, resulting in local oestrogen dominance and progesterone resistance at the receptor level. Recent scientific evidence suggests that the endometrial progesterone receptor resistance encountered in E/A patients can be overcome by a freeze-all policy, followed by down-regulating circulating oestradiol concentrations prior to frozen embryo transfer (FET), in combination with an increase in exogenous luteal phase progesterone supplementation in hormonal replacement therapy (HRT) FET cycles. Specifically, for adenomyosis patients who do not respond to gonadotrophin-releasing hormone agonist down-regulation in terms of a decrease in circulating oestradiol concentrations, a small case series has suggested that the addition of an aromatase inhibitor for 21 days prior to HRT-FET is a valid option. Endometriosis and adenomyosis are hormonally active diseases, which need to be treated by controlling local hyperoestrogenism and progesterone resistance. Based on physiology and recent preliminary clinical data, the authors of this opinion paper wish to stimulate discussion and spark interest in research in E/A patients.

Progesterone resistance in endometriosis: A pathophysiological perspective and potential treatment alternatives.

Background: Endometriosis is a common gynecological disease affecting women of reproductive age. Patients with endometriosis frequently experience severe chronic pain and have higher chances to experience infertility. Progesterone resistance is a major problem that develops during the medical treatment of endometriosis, which often leads to treatment failure of hormonal therapies. Previous studies indicated that the dysregulation of progesterone receptors (PR) is the primary factor leading to progesterone resistance in endometriosis. Methods: This review article systematically reviewed and summarized findings extracted from previously published papers available on PubMed, encompassing both experimental studies and clinical trials. Main findings: Various determinants influencing PR expression in endometriosis have been identified, including the environmental toxins, microRNAs, cell signaling pathways, genetic mutations, and the pro-inflammatory cytokines. The selective estrogen/progesterone receptor modulators have emerged as novel therapeutic approaches for treating endometriosis, offering potential improvements in overcoming progesterone resistance. Conclusion: Concerns and limitations persist despite the newly developed drugs. Therefore, studies on unraveling new therapeutic targets based on the molecular mechanisms of progesterone resistance is warranted for the development potential alternatives to overcome hormonal treatment failure in endometriosis.

Targeting YAP1 ameliorates progesterone resistance in endometriosis.

STUDY QUESTION: Does YAP1 inhibition alleviate progesterone resistance in endometriosis? SUMMARY ANSWER: YAP1 inhibition reduces progesterone resistance in vitro and in vivo. WHAT IS KNOWN ALREADY: Progesterone resistance not only causes treatment failure for endometriosis but also inhibits eutopic endometrial cell proliferation, dysregulates decidualization, and reduces the success rates of pregnancy. Hippo/yes-associated protein 1 (YAP1) signaling pathway plays an important role in the pathogenesis of endometriosis. STUDY DESIGN, SIZE, DURATION: Paraffin-embedded tissues containing paired endometriotic and endometrial specimens (n = 42) and serum samples isolated from normal controls (n = 15) or endometriotic patients with (n = 25) or without (n = 21) prior dienogest treatment were analyzed. A mouse model of endometriosis was also used to evaluate the effects of YAP1 inhibition on progesterone resistance. PARTICIPANTS/MATERIALS, SETTING, METHODS: Primary endometriotic and endometrial stromal cells treated with YAP1 inhibitor or miR-21 mimic/inhibitor were used for the in vitro studies including decidualization induction, chromatin immunoprecipitation (ChIP), and RNA immunoprecipitation. Tissue specimens and serum from human and mouse were used for immunohistochemistry staining, exosome isolation, and microRNA (miRNA) quantification, respectively. MAIN RESULTS AND THE ROLE OF CHANCE: Herein, we report, by using ChIP-PCR and RNA-IP, that YAP1 inhibits progesterone receptor (PGR) expression through upregulation of miR-21-5p. Upregulation of miR-21-5p not only reduces PGR expression but also inhibits endometrial stromal cell decidualization. Indeed, levels of YAP1 and miR-21-5p are inversely correlated with the level of PGR in human endometrial samples. In contrast, knockdown of YAP1 or treatment with verteporfin (VP), a YAP1 inhibitor, reduces miR-21-5p expression, thus leading to an increase in PGR expression in ectopic endometriotic stromal cells. In the mouse model of endometriosis, treatment with VP increases PGR expression and enhances decidualization. More importantly, VP synergistically increases the treatment effect of progestin in causing the regression of endometriotic lesions and improves the decidualization capability of the endometrium. Interestingly, treatment with dienogest, a synthetic progestin, reduces YAP1 and miR-21-5p expression in human cells and in the mouse model of endometriosis. Patients who received dienogest treatment for 6 months show a significant decrease in serum extracellular vesicle-associated miR-21-5p level. LARGE SCALE DATA: A public dataset (GSE51981) containing a large cohort of endometriotic tissues is available from the Gene Expression Omnibus (GEO). LIMITATIONS, REASONS FOR CAUTION: A large cohort of clinical samples is needed to verify the current diagnostic value of miR-21-5p in future studies. WIDER IMPLICATIONS OF THE FINDINGS: The reciprocal regulation of YAP1 and PGR suggests that combined YAP1 inhibitor and progestin may be a better therapeutic approach for treating endometriosis. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the Ministry of Science and Technology, Taiwan (MOST-111-2636-B-006-012, MOST-111-2314-B-006-075-MY3, and MOST-106-2320-B-006-072-MY3). The authors have no conflict of interest to disclose.

Are lower levels of apoptosis and autophagy behind adenomyotic lesion survival?

RESEARCH QUESTION: How are markers of cell death, invasiveness and progesterone signalling expressed in endometrium and ectopic lesions from adenomyosis patients? DESIGN: Formalin-fixed paraffin-embedded tissue was collected from 15 control and 15 adenomyosis participants . To assess cell survival capacity, caspase 3 and microtubule-associated proteins 1A/1B light chain 3B (LC3B) were immunolabelled as markers of apoptosis and autophagy respectively. Matrix metalloproteinase 9 (MMP9) expression served as a marker of extracellular matrix degradation and invasion activity. Progesterone receptors were immunostained to detect evidence of progesterone resistance. RESULTS: Caspase 3 expression was significantly lower in the stromal (P = 0.0013) and epithelial (P = 0.0157) compartments of adenomyotic lesions than in healthy endometrial tissue. In the stroma, caspase 3 expression was significantly weaker in lesions than in corresponding eutopic endometrium (P = 0.0006). LC3B immunostaining was significantly decreased in adenomyotic stroma compared with corresponding eutopic endometrium (P = 0.0349). A significantly higher expression of MMP9 was detected in eutopic stroma from adenomyosis patients than in healthy tissue (P = 0.0295). Progesterone receptor immunostaining was found to be significantly weaker in the stroma of endometrium and ectopic lesions from adenomyosis patients than disease-free women (P = 0.0001; P = 0.0021). CONCLUSIONS: Adenomyotic lesions show lower levels of apoptosis and autophagy, suggesting that aberrant cell survival may be involved in disease pathogenesis. MMP9 appears to contribute to endometrial invasiveness in adenomyosis, as its expression is more pronounced in endometrium from these women than women without the disease. Evidence of progesterone resistance can be found in endometrium and ectopic lesions from adenomyosis patients, and may drive disease development and account for the failure of certain patients to respond to progestogens.

Non-response to first-line hormonal treatment for symptomatic endometriosis: overcoming tunnel vision. A narrative review.

One-fourth to one-third of women with endometriosis receiving first-line hormonal treatment lacks an adequate response in terms of resolution of painful symptoms. This phenomenon has been ascribed to "progesterone resistance", an entity that was theorized to explain the gap between the ubiquity of retrograde menstruation and the 10% prevalence of endometriosis among women of reproductive age.Nevertheless, the hypothesis of progesterone resistance is not free of controversies. As our understanding of endometriosis is increasing, authors are starting to set aside the traditionally accepted tunnel vision of endometriosis as a strictly pelvic disease, opening to a more comprehensive perspective of the condition. The question is: are patients not responding to first-line treatment because they have an altered signaling pathway for such treatment, or have we been overlooking a series of other pain contributors which may not be resolved by hormonal therapy?Finding an answer to this question is evermore impelling, for two reasons mainly. Firstly, because not recognizing the presence of further pain contributors adds a delay in treatment to the already existing delay in diagnosis of endometriosis. This may lead to chronicity of the untreated pain contributors as well as causing adverse consequences on quality of life and psychological health. Secondly, misinterpreting the consequences of untreated pain contributors as a non-response to standard first-line treatment may imply the adoption of second-line medical therapies or of surgery, which may entail non-negligible side effects and may not be free of physical, psychological and socioeconomic repercussions.The current narrative review aims at providing an overview of all the possible pain contributors in endometriosis, ranging from those strictly organic to those with a greater neuro-psychological component. Including these aspects in a broader psychobiological approach may provide useful suggestions for treating those patients who report persistent pain symptoms despite receiving first-line hormonal medical treatment.

In Memory of Ivo Brosens: Reflections on the Pathophysiology of Neonatal Uterine Bleeding.

BACKGROUND: The occurrence of vaginal bleeding in early neonatal life has been observed for centuries and was considered a consequence of the sudden drop in circulating hormones following birth. As such, neonatal uterine bleeding was dismissed as having no clinical significance. Interest in the phenomenon was renewed when a new theory suggested a link between neonatal uterine bleeding (NUB) and accelerated endometrial maturation. This theory was based on the observation of a higher incidence of NUB in babies born post-term or after pregnancies complicated by intrauterine growth restriction, preeclampsia, or blood group incompatibility. OBJECTIVE: The objective of this study was to review of available evidence on the pathogenesis of NUB. METHOD: Review of available literature using Medline search (August 2022, no limit on start date or language) to identify articles that may link NUB with features of the uterus and/or endometrium. OUTCOME: The fetal endometrial responses differ from that of the adult. In the fetus, the endometrium features progestogenic response only in a minority of cases. The endometrium in most newborn girls does not exhibit secretory or decidual changes which indicate lack of progesterone response. Most newborn girls do not have visible bleeding. Animal studies linked exogenous progestogen exposure during the period of organogenesis to poor endometrial gland development, progesterone resistance, and to alterations of reproductive performance. Although the fetal endometrium may not exhibit a full proliferative response, it is clearly sensitive to circulating estrogens. Molecular mechanisms involved in NUB may include "ontogenetic progesterone resistance." CONCLUSION AND OUTLOOK: Endometrial development and its response to withdrawal of hormones at birth varies and may be affected by intrauterine stressors and gestational age. Factors that affect endometrial development during fetal life and in preterm neonates can have implications on future reproductive performance.

MicroRNAs in Endometriosis: Insights into Inflammation and Progesterone Resistance.

Endometriosis, a non-malignant gynecological disorder influenced by estrogen, involves the growth of endometrial tissue outside the uterus. Its development includes processes such as inflammation, progesterone resistance, angiogenesis, and cell proliferation. Epigenetic factors, particularly the dysregulation of microRNAs (miRNAs), have emerged as key factors in these mechanisms in endometriosis. This review aims to unveil the intricate molecular processes that control inflammation, progesterone resistance, and miRNA functions in endometriosis. In addition, it provides a comprehensive overview of the current understanding regarding the involvement of miRNAs in the inflammatory aspects of this condition. This synthesis encompasses research investigating the molecular underpinnings of inflammation, along with the biogenesis and roles of miRNAs in endometriosis. Furthermore, it examines human studies and functional analyses to establish the intricate connection between miRNAs, inflammation, and progesterone resistance in the context of endometriosis. The results highlight the significant impact of dysregulated miRNAs on the inflammatory pathways and hormonal imbalances characteristic of endometriosis. Consequently, miRNAs hold promise as potential non-invasive biomarkers and targeted therapeutic agents aimed at addressing inflammation and enhancing the response to progesterone treatment in individuals with endometriosis.

Progesterone Resistance in Endometriosis: Current Evidence and Putative Mechanisms.

Endometriosis is an estrogen-dependent disease characterized by the growth of endometrial-like tissue outside the uterus. Progestins are currently the most commonly used treatment for endometriosis because of their excellent therapeutic effects and limited side effects. However, progestins have been unsuccessful in some symptomatic patients. The inability of the endometrium to respond properly to progesterone is known as progesterone resistance. An increasing body of evidence suggests the loss of progesterone signaling and the existence of progesterone resistance in endometriosis. The mechanisms of progesterone resistance have received considerable scholarly attention in recent years. Abnormal PGR signaling, chronic inflammation, aberrant gene expression, epigenetic alterations, and environmental toxins are considered potential molecular causes of progesterone resistance in endometriosis. The general objective of this review was to summarize the evidence and mechanisms of progesterone resistance. A deeper understanding of how these mechanisms contribute to progesterone resistance may help develop a novel therapeutic regimen for women with endometriosis by reversing progesterone resistance.

Peritoneal fluid progesterone and progesterone resistance in superficial endometriosis lesions.

Peritoneal fluid in ovulatory women is an ovarian exudate with higher estrogen and progesterone concentrations than in plasma. In the follicular phase, progesterone concentrations are as high as plasma concentrations in the luteal phase. After ovulation, estrogen and progesterone concentrations in the peritoneal fluid are 5-10 times higher than in plasma, both in women with and without endometriosis. The histologically proliferative aspect without secretory changes of most superficial subtle lesions is not compatible with the progesterone concentrations in the peritoneal fluid. Therefore, we have to postulate a strong progesterone resistance in these lesions. The mechanism is unclear and might be a peritoneal fluid effect in women with predisposing defects in the endometrium, or isolated endometrial glands with progesterone resistance, or subtle lesions originating from the basal endometrium: the latter hypothesis is attractive since in basal endometrium progesterone does not induce secretory changes while progesterone withdrawal, not occurring in peritoneal fluid, is required to resume mitotic activity and proliferation. Hormone concentrations in the peritoneal fluid are an important factor in understanding the medical therapy of endometriosis. The effect of oestro-progestin therapy on superficial endometriosis lesions seems to be a consequence of the decreased estrogen concentrations rather than a direct progestin effect. In conclusion, the peritoneal fluid, being a secretion product of the ovarian follicule, deserves more attention in the pathophysiology and treatment of endometriosis.

Hormonal treatments for endometriosis: The endocrine background.

Endometriosis is a benign uterine disorder characterized by menstrual pain and infertility, deeply affecting women's health. It is a chronic disease and requires a long term management. Hormonal drugs are currently the most used for the medical treatment and are based on the endocrine pathogenetic aspects. Estrogen-dependency and progesterone-resistance are the key events which cause the ectopic implantation of endometrial cells, decreasing apoptosis and increasing oxidative stress, inflammation and neuroangiogenesis. Endometriotic cells express AMH, TGF-related growth factors (inhibin, activin, follistatin) CRH and stress related peptides. Endocrine and inflammatory changes explain pain and infertility, and the systemic comorbidities described in these patients, such as autoimmune (thyroiditis, arthritis, allergies), inflammatory (gastrointestinal/urinary diseases) and mental health disorders.The hormonal treatment of endometriosis aims to block of menstruation through an inhibition of hypothalamus-pituitary-ovary axis or by causing a pseudodecidualization with consequent amenorrhea, impairing the progression of endometriotic implants. GnRH agonists and antagonists are effective on endometriosis by acting on pituitary-ovarian function. Progestins are mostly used for long term treatments (dienogest, NETA, MPA) and act on multiple sites of action. Combined oral contraceptives are also used for reducing endometriosis symptoms by inhibiting ovarian function. Clinical trials are currently going on selective progesterone receptor modulators, selective estrogen receptor modulators and aromatase inhibitors. Nowadays, all these hormonal drugs are considered the first-line treatment for women with endometriosis to improve their symptoms, to postpone surgery or to prevent post-surgical disease recurrence. This review aims to provide a comprehensive state-of-the-art on the current and future hormonal treatments for endometriosis, exploring the endocrine background of the disease.

MIG-6 Is Critical for Progesterone Responsiveness in Human Complex Atypical Hyperplasia and Early-Stage Endometrial Cancer.

Women with complex atypical hyperplasia (CAH) or early-stage endometrioid endometrial cancer (EEC) are candidates for fertility preservation. The most common approach is progesterone (P4) therapy and deferral of hysterectomy until after completion of childbearing. However, P4 therapy response rates vary, and molecular mechanisms behind P4 resistance are poorly understood. One potential molecular cause of P4 resistance is a loss or attenuation of PGR expression. Mitogen-inducible gene 6 (MIG-6) is critical for P4 responsiveness. MIG-6 protein expression in the endometrial epithelial and stromal cells from women with CAH and EEC was significantly lower compared to women without CAH or EEC. The P4-responsive women (10/15) exhibited an increase of MIG-6 expression in epithelial and stromal cells compared to P4-resistant women (5/15). In addition, immunohistochemical analysis for PGR results showed that stromal PGR levels are significantly higher in P4-responsive women compared to P4-resistant women, whereas epithelial PGR expression was not different. A reverse correlation of MIG-6 and pAKT levels was observed in early-stage EEC patients. Studies strongly suggest that loss of MIG-6 and PGR and activation of pAKT lead to P4 resistance in CAH and EEC. These results will help to elucidate the molecular mechanism leading to P4 resistance in CAH and EEC.

CNR1 may reverse progesterone-resistance of endometrial cancer through the ERK pathway.

Endocrine therapy is a promising treatment for endometrial cancer (EC) that preserves fertility, however, progesterone-resistance is currently the major challenges. The Cancer Genome Atlas (TCGA) database analysis showed that CNR1 was closely have a negative correlation with overall survival (OS) and relapse-free survival (RFS) in endometrial cancer. To explore the role of CNR1 in progesterone resistance and possible molecular regulation mechanism, we established stable progesterone-resistant cell lines (IshikawaPR) via progesterone tolerance of ordinary cancer cells (Ishikawa). The difference of CNR1 level in two cell lines was assessed by MTT, RT-PCR, Western blot, immunofluorescence. Then, lentiviruses constructed CNR1-knockdown with GV248 as the tool vector were used to transfect IshikwaPR cells, and the changes of biological behavior and progesterone sensitivity was verified respectively through plate cloning experiment, EdU assay, flow cytometry cycle analysis, transwell, Scratch test, etc. We founded after CNR1 was knocked down, the proliferative activity and ability to migrate of IshikawaPR cells decreased, progesterone-response sensitivity could be improved. Moreover, knockdown of CNR1 can also down-regulate ERK and NFκ B expression and activation. Furthermore, subcutaneous xenograft in nude mice was tested similarly in vivo. The above datas suggest that targeting CNR1 may reverse the progesterone resistance in endometrial cancer and may coordinate the role of ERK pathway activation.

A case report of bladder and intestinal endometriosis, and the relationship between sex hormone receptor expression and PIK3CA mutation analysis.

BACKGROUND: Extragonadal endometriosis is a rare condition, and its disease manifestation and long-term prognosis have not been elucidated. We report an extragonadal endometriosis case controlled by drug therapy for 14 years with analysis of the sex hormone receptor expression and PIK3CA mutation. CASE PRESENTATION: The patient was diagnosed with bladder endometriosis at age of 30 years, and underwent bilateral nephrostomy and GnRHa therapy with add-back therapy. The patient was switched to dienogest therapy at age 35 and had hematuria and bloody stools at age 38. PET-CT revealed a 6-cm mass in the bladder with fluorodeoxyglucose accumulation and the diagnosis of endometriosis in the bladder, sigmoid colon, and cecum was confirmed after the biopsy result. The lesion's tubular structures were positive for the estrogen receptor, but only 30% positive for the progesterone receptor, and the H1047R mutation in PIK3CA was found in tubular structures of the bladder lesion. GnRHa therapy caused the tumors to shrink. CONCLUSION: Decreased progesterone receptor expression and oncogenic mutations may influence the course of less common and rare site endometriosis. Rare site endometriosis often requires long-term hormone therapy, and management should be tailored to the patient's life stage, keeping in mind complications, such as decreased bone density.

Low-dose aspirin can downregulate progesterone resistance and increase the expression of LIF in endometriosis during the implantation window.

AIM: Study the effect of low-dose aspirin on the endometrial receptivity in endometriosis rat models. MATERIALS AND METHODS: This study is to explore the expressions of progesterone receptor and LIF among three groups of endometriosis rat models: control group (n = 12), EMs group (n = 15), and aspirin group (n = 17). The expressions of progesterone receptor (PR), PRA, PRB, and leukemia inhibitory factor receptor (LIFR) in eutopic endometrium were determined using immunohistochemistry technology, western blot, and qRT-PCR. The levels of LIF in eutopic endometrium and serum were detected by western blot, qRT-PCR, and ELISA. RESULTS: The expressions of PR, PRA, and PRB protein were significantly increased in the eutopic endometrium after low-dose aspirin treatment, and the level of PRB mRNA was also increased while the ratio of PRA/PRB mRNA was decreased in the eutopic endometrium. The levels of LIF in eutopic endometrium and serum were increased compared with the untreated endometriosis rats. However, the expression of LIFR was not statistically different among the three groups. CONCLUSIONS: The results suggest that the low-dose aspirin treatment could downregulate progesterone resistance and increase the expression of LIF of endometriosis rats during the implantation window, which could improve endometrial receptivity and enhance the pregnant rate of endometriosis. It may provide a potential treatment method for endometriosis-related infertility.

Therapeutic Potentials of Low-Dose Tacrolimus for Aberrant Endometrial Features in Polycystic Ovary Syndrome.

Polycystic ovary syndrome (PCOS) is a major anovulatory infertility affecting a great proportion of women of childbearing age and is associated with obesity, insulin resistance and chronic inflammation. Poor endometrial receptivity and recurrent implantation failure are major hurdles to the establishment of pregnancy in women with PCOS. The accumulating body of evidence obtained from experimental and clinical studies suggests a link between inherent adaptive and innate immune irregularities and aberrant endometrial features in PCOS. The use of conventional therapeutic interventions such as lifestyle modification, metformin and ovarian stimulation has achieved limited clinical success in restoring ovulation and endometrial receptivity in women with PCOS. Unlike other immunosuppressive drugs prescribed in the clinical management of autoimmune and inflammatory disorders that may have deleterious effects on fertility and fetal development, preclinical studies in mice and in women without PCOS but with repeated implantation failure revealed potential therapeutic benefits for the use of low-dose tacrolimus in treating female infertility. Improved systemic and ovarian immune functions, endometrial progesterone receptor and coreceptor expressions and uterine vascular adaptation to pregnancy were among features of enhanced progesterone-receptor sensitivity in the low-dose tacrolimus-treated mouse model of the disease. In this review, we have compiled available experimental and clinical data in literature on endometrial progesterone resistance and current therapeutic options, as well as mechanisms of actions and reported outcomes relevant to the potential therapeutic benefits for the use of low-dose tacrolimus in treating PCOS-associated female infertility.

GnRH Antagonists with or without Add-Back Therapy: A New Alternative in the Management of Endometriosis?

To evaluate the effectiveness of a new class of medical drugs, namely oral gonadotropin-releasing hormone (GnRH) antagonists, in the management of premenopausal women with endometriosis-associated pelvic pain. We reviewed the most relevant papers (n = 27) on the efficacy of new medical alternatives (oral GnRH antagonists) as therapy for endometriosis. We first briefly summarized the concept of progesterone resistance and established that oral contraceptives and progestogens work well in two-thirds of women suffering from endometriosis. Since clinical evidence shows that estrogens play a critical role in the pathogenesis of the disease, lowering their levels with oral GnRH antagonists may well prove effective, especially in women who fail to respond to progestogens. There is a need for reliable long-term oral treatment capable of managing endometriosis symptoms, taking into consideration both the main symptoms and phenotype of the disease. Published studies reviewed and discussed here confirm the efficacy of GnRH antagonists. There is a place for GnRH antagonists in the management of symptomatic endometriosis. Novel algorithms that take into account the different phenotypes are proposed.

Comprehensive bioinformatics analysis of acquired progesterone resistance in endometrial cancer cell line.

BACKGROUND: Progesterone resistance is a problem in endometrial carcinoma, and its underlying molecular mechanisms remain poorly understood. The aim of this study was to elucidate the molecular mechanisms of progesterone resistance and to identify the key genes and pathways mediating progesterone resistance in endometrial cancer using bioinformatics analysis. METHODS: We developed a stable MPA (medroxyprogesterone acetate)-resistant endometrial cancer cell subline named IshikawaPR. Microarray analysis was used to identify differentially expressed genes (DEGs) from triplicate samples of Ishikawa and IshikawaPR cells. PANTHER, DAVID and Metascape were used to perform gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and cBioPortal for progesterone receptor (PGR) coexpression analysis. GEO microarray (GSE17025) was utilized for validation. The protein-protein interaction network (PPI) and modular analyses were performed using Metascape and Cytoscape. Further validation were performed by real-time polymerase chain reaction (RT-PCR). RESULTS: In total, 821 DEGs were found and further analyzed by GO, KEGG pathway enrichment and PPI analyses. We found that lipid metabolism, immune system and inflammation, extracellular environment-related processes and pathways accounted for a significant portion of the enriched terms. PGR coexpression analysis revealed 7 PGR coexpressed genes (ANO1, SOX17, CGNL1, DACH1, RUNDC3B, SH3YL1 and CRISPLD1) that were also dramatically changed in IshikawaPR cells. Kaplan-Meier survival statistics revealed clinical significance for 4 out of 7 target genes. Furthermore, 8 hub genes and 4 molecular complex detections (MCODEs) were identified. CONCLUSIONS: Using microarray and bioinformatics analyses, we identified DEGs and determined a comprehensive gene network of progesterone resistance. We offered several possible mechanisms of progesterone resistance and identified therapeutic and prognostic targets of progesterone resistance in endometrial cancer.

Progesterone and Estrogen Signaling in the Endometrium: What Goes Wrong in Endometriosis?

In the healthy endometrium, progesterone and estrogen signaling coordinate in a tightly regulated, dynamic interplay to drive a normal menstrual cycle and promote an embryo-receptive state to allow implantation during the window of receptivity. It is well-established that progesterone and estrogen act primarily through their cognate receptors to set off cascades of signaling pathways and enact large-scale gene expression programs. In endometriosis, when endometrial tissue grows outside the uterine cavity, progesterone and estrogen signaling are disrupted, commonly resulting in progesterone resistance and estrogen dominance. This hormone imbalance leads to heightened inflammation and may also increase the pelvic pain of the disease and decrease endometrial receptivity to embryo implantation. This review focuses on the molecular mechanisms governing progesterone and estrogen signaling supporting endometrial function and how they become dysregulated in endometriosis. Understanding how these mechanisms contribute to the pelvic pain and infertility associated with endometriosis will open new avenues of targeted medical therapies to give relief to the millions of women suffering its effects.

MIG-6 suppresses endometrial epithelial cell proliferation by inhibiting phospho-AKT.

BACKGROUND: Aberrant hyperactivation of epithelial proliferation, AKT signaling, and association with unopposed estrogen (E2) exposure is the most common endometrial cancer dysfunction. In the normal uterus, progesterone (P4) inhibits proliferation by coordinating stromal-epithelial cross-talk, which we previously showed is mediated by the function of Mitogen-inducible gene 6 (Mig-6). Despite their attractive characteristics, non-surgical conservative therapies based on progesterone alone have not been universally successful. One barrier to this success has been the lack of understanding of the P4 effect on endometrial cells. METHOD: To further understand the role of Mig-6 and P4 in controlling uterine proliferation, we developed a Sprr2f-cre driven mouse model where Mig-6 is specifically ablated only in the epithelial cells of the uterus (Sprr2f cre+ Mig-6 f/f ). We examined P4 effect and regulation of AKT signaling in the endometrium of mutant mice. RESULTS: Sprr2f cre+ Mig-6 f/f mice developed endometrial hyperplasia. P4 treatment abated the development of endometrial hyperplasia and restored morphological and histological characteristics of the uterus. P4 treatment reduced cell proliferation which was accompanied by decreased AKT signaling and the restoration of stromal PGR and ESR1 expression. Furthermore, our in vitro studies revealed an inhibitory effect of MIG-6 on AKT phosphorylation as well as MIG-6 and AKT protein interactions. CONCLUSIONS: These data suggest that endometrial epithelial cell proliferation is regulated by P4 mediated Mig-6 inhibition of AKT phosphorylation, uncovering new mechanisms of P4 action. This information may help guide more effective non-surgical interventions in the future.