Conclusions
Leiomyoma-secreted TGF-β3 induces BMP-2 resistance in endometrium by down-regulation of BMPR-2, likely causing defective endometrial decidualization. TGF-β3 also reduces expression of PAI-1, ATIII, and thrombomodulin in endometrium, likely contributing to menorrhagia. A single molecular signal targeting endometrium may mediate both leiomyoma-induced infertility and bleeding.
Results
ESC from controls secreted more BMP-2 than those from women with leiomyoma. HOXA10 and LIF expression increased after rhBMP-2 treatment of normal but not leiomyoma-associated ESC. In vivo leiomyoma-associated endometrium expressed lower levels of BMPR 1A, 1B, and 2 than controls. Leiomyoma expressed high levels of TGF-β3; TGF-β3 treatment of ESC reduced expression of BMPRs. Similarly, leiomyoma-associated endometrium expressed less PAI-1 and thrombomodulin in vivo. In ESC, TGF-β3 reduced expression of PAI-1, ATIII, and thrombomodulin. Conclusions: Leiomyoma-secreted TGF-β3 induces BMP-2 resistance in endometrium by down-regulation of BMPR-2, likely causing defective endometrial decidualization. TGF-β3 also reduces expression of PAI-1, ATIII, and thrombomodulin in endometrium, likely contributing to menorrhagia. A single molecular signal targeting endometrium may mediate both leiomyoma-induced infertility and bleeding.