Heterogeneity of estrogen receptor α and progesterone receptor distribution in lesions of deep infiltrating endometriosis of untreated women or during exposure to various hormonal treatments

New concepts on the etiology of endometriosis

Endometriosis is a serious, chronic disorder where endometrial tissue grows outside the uterus, causing severe pelvic pain and infertility. It affects 11% of women. Endometriosis is a multifactorial disorder of unclear etiology, although retrograde menstruation plays a major role. It has a genetic component with over 40 genetic risk factors mapped, although their mechanism of action is still emerging. New evidence suggests a role for retrograde menstruation of endometrial stem/progenitor cells, now that identifying markers of these cells are available. Recent lineage tracing and tissue clearing microscopy and 3D reconstruction has provided new understanding of endometrial glandular structure, particularly the horizontal orientation and interconnection of basalis glands. New sequencing technologies, particularly whole genome DNA sequencing are revealing somatic mutations, including in cancer driver genes, in normal and eutopic endometrium of patients with endometriosis, as well as ectopic endometriotic lesions. Methylome sequencing is offering insight into the regulation of genes and the role of the environmental factors. Single cell RNA sequencing reveals the transcriptome of individual endometrial cells, shedding new light on the diversity and range of cellular subpopulations of the major cell types present in the endometrium and in endometriotic lesions. New endometrial epithelial organoid cultures replicating glandular epithelium are providing tractable models for studying endometriosis. Organoids derived from menstrual fluid offer a non-invasive source of endometrial tissue and a new avenue for testing drugs and developing personalized medicine for treating endometriosis. These new approaches are rapidly advancing our understanding of endometriosis etiology.

Randomized study on the effectiveness of nomegestrol acetate plus 17β-estradiol oral contraceptive versus dienogest oral pill in women with suspected endometriosis‑associated chronic pelvic pain

Background

To evaluate the effects of a combined oral contraceptive containing 1.5 mg 17b-estradiol (E2) and 2.5 mg nomegestrol acetate (NOMAC) or 2 mg/daily dienogest (DNG) oral progestin on endometriosis-associated chronic pelvic pain (CPP) and on the quality of life (QoL) and sexual function, by a randomized study design.

Methods

The E2/NOMAC group and DNG group included 99 and 98 women, respectively. The levels of CPP were measured by the visual analogic scale (VAS). The QoL scores were investigated by the Short Form-36 questionnaire (SF-36). Finally, sexual function was studied using the Female Sexual Function Index (FSFI), while sexual distress was studied by the Female Sexual Distress Scale (FSDS). The study had 3, 6 and 12-month follow-ups.

Results

The intra-group analysis showed an improvement of the VAS score from baseline to the 12-month follow-up in the women of both groups (p < 0.001). The inter-group comparison showed a similar improvement of CPP (p = 0.06). Women on DNG had better SF-36 somatic (p < 0.01) and FSFI scores (p < 0.006) than women on E2/NOMAC at the 6- and 12-month follow-ups.

Conclusions

The results support the efficacy of both hormonal treatments, even if DNG was more effective than E2/NOMAC in a limited intergroup comparison.

New Therapeutics in Endometriosis: A Review of Hormonal, Non-Hormonal, and Non-Coding RNA Treatments

Endometriosis is defined as endometrial-like tissue outside the uterine cavity. It is a chronic inflammatory estrogen-dependent disease causing pain and infertility in about 10% of women of reproductive age. Treatment nowadays consists of medical and surgical therapies. Medical treatments are based on painkillers and hormonal treatments. To date, none of the medical treatments have been able to cure the disease and symptoms recur as soon as the medication is stopped. The development of new biomedical targets, aiming at the cellular and molecular mechanisms responsible for endometriosis, is needed. This article summarizes the most recent medications under investigation in endometriosis treatment with an emphasis on non-coding RNAs that are emerging as key players in several human diseases, including cancer and endometriosis.

Progesterone receptor ligands for the treatment of endometriosis: the mechanisms behind therapeutic success and failure

BACKGROUND

Despite intense research, it remains intriguing why hormonal therapies in general and progestins in particular sometimes fail in endometriosis.

OBJECTIVE AND RATIONALE

We review here the action mechanisms of progesterone receptor ligands in endometriosis, identify critical differences between the effects of progestins on normal endometrium and endometriosis and envisage pathways to escape drug resistance and improve the therapeutic response of endometriotic lesions to such treatments.

SEARCH METHODS

We performed a systematic Pubmed search covering articles published since 1958 about the use of progestins, estro-progestins and selective progesterone receptor modulators, to treat endometriosis and its related symptoms. Two reviewers screened the titles and abstracts to select articles for full-text assessment.

OUTCOMES

Progesterone receptor signalling leads to down-regulation of estrogen receptors and restrains local estradiol production through interference with aromatase and 17 beta-hydroxysteroid dehydrogenase type 1. Progestins inhibit cell proliferation, inflammation, neovascularisation and neurogenesis in endometriosis. However, progesterone receptor expression is reduced and disrupted in endometriotic lesions, with predominance of the less active isoform (PRA) over the full-length, active isoform (PRB), due to epigenetic abnormalities affecting the PGR gene transcription. Oxidative stress is another mechanism involved in progesterone resistance in endometriosis. Among the molecular targets of progesterone in the normal endometrium that resist progestin action in endometriotic cells are the nuclear transcription factor FOXO1, matrix metalloproteinases, the transmembrane gap junction protein connexin 43 and paracrine regulators of estradiol metabolism. Compared to other phenotypes, deep endometriosis appears to be more resistant to size regression upon medical treatments. Individual genetic characteristics can affect the bioavailability and pharmacodynamics of hormonal drugs used to treat endometriosis and, hence, explain part of the variability in the therapeutic response.

WIDER IMPLICATIONS

Medical treatment of endometriosis needs urgent innovation, which should start by deeper understanding of the disease core features and diverse phenotypes and idiosyncrasies, while moving from pure hormonal treatments to drug combinations or novel molecules capable of restoring the various homeostatic mechanisms disrupted by endometriotic lesions.

Aldo-keto reductase 1C3-Assessment as a new target for the treatment of endometriosis

Endometriosis is a common gynecological disorder, which is treated surgically and/ or pharmacologically with an unmet clinical need for new therapeutics. A completed phase I trial and a recent phase II trial that investigated the steroidal aldo-keto reductase 1C3 (AKR1C3) inhibitor BAY1128688 in endometriosis patients prompted this critical assessment on the role of AKR1C3 in endometriosis. This review includes an introduction to endometriosis with emphasis on the roles of prostaglandins and progesterone in its pathophysiology. This is followed by an overview of the major enzymatic activities and physiological functions of AKR1C3 and of the data published to date on the expression of AKR1C3 in endometriosis at the mRNA and protein levels. The review concludes with the rationale for using AKR1C3 inhibitors, a discussion of the effects of AKR1C3 inhibition on the pathophysiology of endometriosis and a brief overview of other drugs under clinical investigation for this indication.

Endometriosis: advances and controversies in classification, pathogenesis, diagnosis, and treatment

Endometriosis is an enigmatic disease that could start at birth. Its pathogenesis is supported by different theories. Accumulating facts relate it to a multigenic disorder. In this review of recent publications, the principal symptoms of the disease, pain and infertility, as well as its pathogenesis, diagnosis, and classification will be addressed. Endometriosis presents three main variants: superficial peritoneal disease, deep infiltrating endometriosis, and ovarian endometriomas. The management of the disease, surgery, and medical and alternative therapies will be discussed. Special reference will be made to the quality of surgery and how to understand patients with endometriosis and endometriosis.

Progesterone Receptor Status Predicts Response to Progestin Therapy in Endometriosis

Context

Progestin-based therapy is the first-line treatment for managing endometriosis-associated pain. However, response to progestins is currently variable and unpredictable. Predictive markers for response to progestin-based therapy would allow for a personalized approach to endometriosis treatment.

Objective

We hypothesize that progesterone receptor (PR) levels in endometriotic lesions determine response to progestin-based therapy.

Design

Retrospective cohort study.

Setting

Academic center.

Patients

Fifty-two subjects with histologically confirmed endometriosis and a previous documented response to hormonal therapy were included.

Interventions

Immunohistochemistry was performed on sections of endometriotic lesions using a rabbit polyclonal IgG for detection of PR-A/B.

Main Outcome Measures

The Histo (H)-score was used for quantifying PR status. Response to progestin-based therapies was determined from review of the electronic medical record.

Results

H-score was higher in responders compared with nonresponders. Subjects were categorized into three groups: high (H-score > 80, n = 7), medium (H-score 6 to 80, n = 28), and low (H-score ≤ 5, n = 17) PR status. The threshold of PR > 80 was associated with a 100% positive predictive value. The threshold of PR < 5 was associated with a 94% negative predictive value.

Conclusion

PR status is strongly associated with response to progestin-based therapy. Receptor status in endometriosis could be used to tailor hormonal-based regimens after surgery, and negate trialing progestin-based therapy to determine resistance. Ascertainment of PR status may allow for a novel, targeted, precision-based approach to treating endometriosis.