Inhibition of canonical WNT signaling attenuates human leiomyoma cell growth

Ono, Masanori; Yin, Ping; Navarro, Antonia; Moravek, Molly B.; Coon, John S.; Druschitz, Stacy A.; Gottardi, Cara J.; Bulun, Serdar E.

OBJECTIVE: Dysregulation of WNT signaling plays a central role in tumor cell growth and progression. Our goal was to assess the effect of three WNT/β-catenin pathway inhibitors, Inhibitor of β-Catenin And TCF4 (ICAT), niclosamide, and XAV939 on the proliferation of primary cultures of human uterine leiomyoma cells. DESIGN: Prospective study of human leiomyoma cells obtained from myomectomy or hysterectomy. SETTING: University research laboratory. PATIENT(S): Women (n=38) aged 27–53 years undergoing surgery. INTERVENTION(S): Adenoviral ICAT overexpression or treatment with varying concentrations of niclosamide or XAV939. MAIN OUTCOME MEASURE(S): Cell proliferation, cell death, WNT/β-catenin target gene expression or reporter gene regulation, β-catenin levels and cellular localization. RESULT(S): ICAT, niclosamide, or XAV939 inhibit WNT/β-catenin pathway activation and exert anti-proliferative effects in primary cultures of human leiomyoma cells. CONCLUSION(S): Three WNT/β-catenin pathway inhibitors specifically block human leiomyoma growth and proliferation, suggesting that the canonical WNT pathway may be a potential therapeutic target for the treatment of uterine leiomyoma. Our findings provide rationale for further preclinical and clinical evaluation of ICAT, niclosamide, and XAV939 as candidate anti-tumor agents for uterine leiomyoma.