Rethinking the Estrogen Receptor Beta Dominance Hypothesis in Endometriosis: Insights from Single Cell RNA Sequencing...

Area of Science:

• Reproductive Biology
• Molecular Medicine
• Genomics

Background:

• Endometriosis is a complex, estrogen-dependent disease with significant diagnostic and therapeutic challenges.
• Current understanding suggests increased estrogen receptor beta (ERβ) expression drives lesion proliferation, making ERβ a key therapeutic target.
• The 'ERβ dominance hypothesis' posits ERβ as the primary driver in endometriosis, influencing treatment strategies.

Purpose of the Study:

• To comprehensively analyze ERβ expression across different cell types in endometriosis.
• To evaluate the therapeutic relevance of ERβ by testing the validity of the ERβ dominance hypothesis.
• To characterize cell-type specific expression patterns of estrogen receptors.

Main Methods:

• Reanalysis of single-cell RNA sequencing data from eight published studies, creating the largest endometriosis single-cell atlas (557,061 cells).
• Quantification of ESR1 (ERα) and ESR2 (ERβ) gene expression across various tissue and cell types.
• Differential gene expression and pathway enrichment analyses to compare cells expressing ERα versus ERβ.

Main Results:

• Statistical analyses revealed no significant ESR2/ERβ dominance in any cell or tissue type.
• Differential expression analyses indicated distinct functional roles for ERα and ERβ isoforms.
• The study provides a detailed cell-type specific map of estrogen receptor expression in endometriosis.

Conclusions:

• The findings challenge the simplified ERβ dominance hypothesis in endometriosis.
• A dual-isoform, cell- and tissue-specific framework is proposed for understanding estrogen receptor signaling.
• Future endometriosis therapies should consider isoform-specific, tissue-specific, and cell-specific expression patterns for improved efficacy and reduced recurrence.