Regulatory Role for Tumor Suppressor REST on Estrogen Receptor (ESR1) Expression and Leiomyoma Pathophysiology

Area of Science:

• Reproductive biology
• Epigenetics
• Molecular endocrinology

Background:

• Uterine leiomyomas (fibroids) affect most women by age 50, with unclear pathophysiology.
• Current preclinical models and in vitro systems struggle to replicate uterine leiomyoma hormone signaling.
• Estrogen receptor alpha (ESR1) and progesterone receptor (PGR) expression is rapidly lost in cultured uterine smooth muscle cells, limiting research.

Purpose of the Study:

• Investigate the role of REST (repressor of silencing) in uterine leiomyoma development and hormone receptor regulation.
• Identify mechanisms by which REST influences ESR1 and PGR expression.
• Explore REST's potential as a therapeutic target and its role in epigenetic regulation of uterine leiomyoma.

Main Methods:

• Chromatin immunoprecipitation (ChIP-PCR and ChIP-seq) in mouse models and cell cultures.
• Analysis of REST association with ESR1 and PGR genomic loci.
• Investigation of PRICKLE1's role in REST-mediated ESR1 regulation.

Main Results:

• REST directly binds to the ESR1 locus, epigenetically regulating its expression.
• Loss of REST in mouse models globally affects PGR target genes and alters PGR binding at the ESR1 locus.
• REST's inhibition of ESR1 is linked to the WNT pathway molecule PRICKLE1.
• REST's function in silencing ESR1 in cultured cells suggests potential for REST modulation to maintain ESR1 expression.

Conclusions:

• REST is a key epigenetic regulator in uterine leiomyoma pathophysiology.
• REST plays a critical role in maintaining normal estrogen and progesterone signaling pathways.
• REST modulation presents a potential strategy for novel cell culture techniques and therapeutic interventions for uterine leiomyoma.