Histone deacetylase inhibition by suberoylanilide hydroxamic acid: a therapeutic approach to treat human uterine leiomyoma

Abstract

Objective: To evaluate the effect of inhibition of histone deacetylases (HDACs) by suberoylanilide hydroxamic acid (SAHA) treatment of human uterine leiomyoma primary (HULP) cells in vitro on cell proliferation, cell cycle, extracellular matrix (ECM) formation, and transforming growth factor β3 (TGF-β3) signaling.

Design: Prospective study comparing uterine leiomyoma (UL) vs. adjacent myometrium (MM) tissue and cells with or without SAHA treatment.

Setting: Hospital and university laboratories.

Patient(s): Women with UL without any hormone treatment.

Intervention(s): Myomectomy or hysterectomy surgery in women for leiomyoma disease.

Main outcome measure(s): HDAC activity was assessed by enzyme-linked immunosorbent assay, and gene expression was assessed by quantitative real-time polymerase chain reaction. Effects of SAHA on HULP cells were analyzed by CellTiter (Promega, Madison, Wisconsin), Western blot, and quantitative real-time polymerase chain reaction.

Result(s): The expression of HDAC genes (HDAC1, fold change [FC] = 1.65; HDAC3, FC = 2.08; HDAC6, FC = 2.42) and activity (0.56 vs. 0.10 optical density [OD]/h/mg) was significantly increased in UL vs. MM tissue. SAHA decreased HDAC activity in HULP cells but not in MM cells. Cell viability significantly decreased in HULP cells (81.68% at 5 μM SAHA, 73.46% at 10 μM SAHA), but not in MM cells. Proliferating cell nuclear antigen expression was significantly inhibited in SAHA-treated HULP cells (5 μM SAHA, FC = 0.556; 10 μM SAHA, FC = 0.622). Cell cycle markers, including C-MYC (5 μM SAHA, FC = 0.828) and CCND1 (5 μM SAHA, FC = 0.583; 10 μM SAHA, FC = 0.482), were significantly down-regulated after SAHA treatment. SAHA significantly inhibited ECM protein expression, including FIBRONECTIN (5 μM SAHA, FC = 0.815; 10 μM SAHA, FC = 0.673) and COLLAGEN I (5 μM SAHA, FC = 0.599; 10 μM SAHA, FC = 0.635), in HULP cells. TGFβ3 and MMP9 gene expression was also significantly down-regulated by 10 μM SAHA (TGFβ3, FC = 0.596; MMP9, FC = 0.677).

Conclusion(s): SAHA treatment inhibits cell proliferation, cell cycle, ECM formation, and TGF-β3 signaling in HULP cells, suggesting that histone deacetylation may be useful for treatment of UL.

Keywords: Cell proliferation; SAHA; ULS-β3 pathway; extracellular matrix; uterine leiomyoma.