Endometriosis · Pathophysiology

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

Mercorio A, Giampaolino P, Romano A, Dällenbach P, Pluchino N

Published September 20, 2022 Frontiers in Endocrinology, 13, 950866
DOI 10.3389/fendo.2022.950866 PMID 36204107 PMC PMC9531311

RRM Academy Synopsis

Endometriosis lesions appear to make estrogen locally, a review finds

Endometriosis lesions appear to make estrogen locally, but human studies of the enzymes involved conflict. This review covered 40 studies of how lesion tissue makes and breaks down estrogen. Study methods differed, and many lacked symptom and stage data.

Key Findings

  • The search retrieved 1023 articles after duplicates were removed, and 40 articles were included in the review.
  • The review covered aromatase, HSD17B types 1, 2 and 5, steroid sulfatase and estrogen sulfotransferase, and described aromatase findings in human tissue as conflicting.
  • Seven clinical trials compared aromatase inhibitors with other endometriosis treatments. Four studies with more than 200 patients found comparable pain reduction between these regimens and standard hormonal treatments.
  • One trial with a 24-month follow-up recorded recurrence in 3/40 (8%) of women on an aromatase inhibitor plus goserelin and 14/40 (35%) on goserelin alone.
  • A phase II trial of an AKR1C3 inhibitor, BAY1128688, in women with endometriosis was stopped early because of hepatotoxicity.

Interpretation

The paper is a systematic review of 40 studies in people with endometriosis. Many measured enzyme levels in tissue samples, with different lab methods, modest group sizes and often no stage or symptom data. The authors call the evidence heterogeneous. Many studies lacked links to symptom severity, so the review cannot say which patients an enzyme-targeted drug would help. The authors say the clinical value of aromatase inhibitors is still under investigation.

RRM Context

The review reports that all available therapies reduce gonadal activity as their main mechanism, while lesions may keep making estrogen on their own. It links higher recurrence after excision of ovarian lesions to their likely greater hormone activity. Restorative reproductive medicine looks for the underlying disease. Excision removes the lesion tissue. Suppressive medications leave it in place.

Abstract

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.

Topics

By this author

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Endometriosis › Pathophysiology › Origin Theories · Therapeutics › Hormonal Agents › Estrogen Preparations · Reproductive Endocrinology › Ovarian Hormones › Estrogen
Antonio Mercorio, Pierluigi Giampaolino, Andrea Romano, Patrick Dällenbach, Nicola Pluchino
A Mercorio, P Giampaolino, A Romano, Pat Dällenbach, P Dällenbach, N Pluchino
PMID 36204107 36204107 DOI 10.3389/fendo.2022.950866 10.3389/fendo.2022.950866 Mercorio et al. 2022, Mercorio 2022

Correction published 2023