Promoter Hypermethylation of Progesterone Receptor Isoform B (PR-B) in Adenomyosis and Its Rectification by a Histone Deacetylase Inhibitor and a Demethylation Agent

Abstract

Adenomyosis is a fairly common gynecologic disease with unknown pathogenesis. We sought to investigate as to whether the promoter of progesterone receptor isoform B (PR-B) is hypermethylated in adenomyosis and to investigate the treatment of ectopic endometrial stromal cells with trichostatin A (TSA), a histone deacetylase inhibitor (HDI), and 5-aza-2-deoxycytidine (ADC), a demethylation agent, on PR-B gene and protein expression, and on cell viability. Ectopic endometrial tissue specimens were obtained from 9 women with adenomyosis whereas control endometrial tissue samples were obtained from 8 women with surgically diagnosed benign ovarian cysts but without any clinical history of endometriosis/adenomyosis/ myoma. Endometrial stromal cells were isolated, purified, cultured, and analyzed by methylation-specific polymerase chain reaction (PCR), real-time reverse transcriptase PCR (RT-PCR), and Western blot analysis, cell viability assays, and fluorescence-activated cell sorting. We found that none of the normal endometrial stromal cells had PR-B promoter methylation. In contrast, 2 out of 3 ectopic endometrial stromall cells had PR-B hypermethylation (P < .05). The treatment with both TSA and ADC elevated PR-B gene and protein expression in ectopic, but not in normal, endometrial stromal cells. Both TSA and ADC treatment dose-dependently reduced cell viability of ectopic endometrial stromal cells. Trichostatin A and ADC treatment also suppressed the cell cycle progression in ectopic endometrial stromal cells. Thus, this study provides the first piece of evidence that adenomyosis has epigenetic aberration and may also be an epigenetic disease amenable to rectification by pharmacological means. This perspective may shed new light onto the pathogenesis of adenomyosis and lead to novel ways to treat the disease.

Possible Loss of GABAergic Inhibition in Mice With Induced Adenomyosis and Treatment With Epigallocatechin-3-Gallate Attenuates the Loss With Improved Hyperalgesia

“…These results also suggest that, in preclinical studies of potential therapeutic agents, these 3 measurements may serve as biomarkers gauging the potential efficacy. Indeed, PR-B is known to be involved in adenomyosis, 46,68 and as a transcription factor it may be a pivotal player. Myometrial OTR also seems to play a role in symptomatic adenomyosis.…”

Epigallocatechin-3-Gallate Reduces Myometrial Infiltration, Uterine Hyperactivity, and Stress Levels and Alleviates Generalized Hyperalgesia in Mice Induced With Adenomyosis

“…We have previously shown that progesterone receptor isoform B (PR-B) is hypermethylated in adenomyosis, which leads to PR-B silencing and possibly accounts for progesterone resistance, and, as such, histone deacetylase inhibitors and demethylation agents may be useful in reactivating PR-B and suppressing proliferation of ectopic endometrial tissues. 16 In addition, we have recently shown aberrant immunoreactivity to DNA methyl transferase (DNMT)-1 and DNMT-3B and also to class I histone deacetylases (HDACs) in adenomyosis. 17,18 The EGCG has been shown to suppress DNMTs and decrease HDAC activity, resulting in the reactivation of methylation-silenced genes.…”

Elevated Immunoreactivity against Class I Histone Deacetylases in Adenomyosis

“…First, a pilot study has shown that the use of valproic acid (VPA), a histone deacetylase inhibitor (HDACI), resulted in the relief of dysmenorrhea and the reduction of uterus size in women with symptomatic adenomyosis [5]. Second, it has been shown that, as in endometriosis [6], the progesterone receptor isoform B is hypermethylated and can be reactivated by an HDACI and/or a demethylation agent [7]. Our very recent study on a 12-patient case series indicates that the 3-month oral administration of VPA completely resolves dysmenorrhea and reduces the amount of menses and uterus size [8].…”