Abstract

Transforming growth factor beta1 expression in uterine leiomyomas and adjacent myometrium

Author(s): Antigone Sourla, Ioanna Gaka, Peter Lembessis, Stelios Michalas, George Creatsas and Michael Koutsilieris

Objective: To analyze the expression of transforming growth factor (TGF)β1 in human uterine leiomyomas and adjacent myometrium obtained at hysterectomy of women at mid/late follicular phase (n = 15), at mid/late luteal phase (n = 12) and after sex steroid ablation therapy. Materials and methods: Sex steroid ablation therapy was carried out using luteinizing-hormone-releasing hormone analog (triptorelin 3.75 mg intramuscularly every 28 days for at least 3 months; n = 10) and postmenopause (n = 8). The expression of TGFβ1 mRNA was analyzed by northern blots and in situ hybridization analysis while the immunohistochemical analysis assessed TGFβ1 expression at protein levels. In addition, we tested the time- and dose-dependent effects of TGFβ1 (0.5– 50 ng/ml; final concentration; 24 and 48 h) on the proliferation (cell number; trypan blue exclusion) of KW smooth muscle-like myometrial cells in vitro. Results: Our data demonstrated that TGFβ1 (mRNA and protein) expression was higher in leiomyomas at mid/late follicular phase compared with those at luteal phase and to adjacent myometrium at either phases of the menstrual cycle. However, TGFβ1 expression (mRNA and protein) did not differ significantly among leiomyomas at luteal phase, leiomyomas after luteinizing-hormone-releasing hormone analog therapy, myometrium at follicular phase, myometrium at luteal phase and myometrium postmenopause. Conclusion: We conclude that TGFβ1 may be an important autocrine/paracrine factor in human leiomyomas particularly during the mid/late follicular phase.