Analysis of leiomyomas from UPA-treated women by western blot revealed significant reductions of active TGF-β3 (0.64 ± 0.12-fold), p-TGFR2 (0.56 ± 0.23-fold), pSmad 2 (0.54 ± 0.04-fold), and pSmad 3 (0.65 ± 0.09-fold) compared with untreated leiomyomas.
The subcultured UL cells were used to determine the validation of TGF-β3 for the viability of human UL cells using CCK-8 assay, mRNA expressions of ERα, and c-fos by quantitative reverse transcription polymerase chain reaction method, and expressions of p-Smad3, SnoN, and c-fos proteins by Western blot assay in each treatment group.
The growth factors with mitogenic activity, such as transforming growth factor-β3, fibroblast growth factor, epidermal growth factor, and insulin-like growth factor-I are elevated in fibroids and may have a role as effectors of the tumor promotion.
Myometrial cells in 3D culture responded to TGF-β3 with increased gene expression of collagen 1A1, fibronectin, and versican, and decreased expression of dermatopontin gene recapitulating the leiomyoma phenotype.
In vivo mRNA levels of Egr-2 were statistically significantly higher in leiomyoma tissues compared with matched myometrial tissues, and showed a statistically significant correlation with TGF-β3 messenger RNA (mRNA) levels in leiomyoma tissues.
Real-time PCR, Western blotting and immunohistochemistry revealed that leiomyomas and myometrium express CCNs, fibulin-1C and S100A4, whose levels of expression with the exception of fibulin-1C were lower in leiomyomas and inversely correlated with the expression of TGF-beta1 and TGF-beta3 (P<0.05).
Reduction in dermatopontin was associated with an increase in transforming growth factor-beta3 (TGFB3) mRNA levels in leiomyomas, whereas other genes involved in dermatopontin signaling were not differentially expressed.