TGFB1 and leiomyoma: Similarly, Norian et al. (2009) [65] demonstrated that TGF-β mRNA transcripts were increased in leiomyoma cells as compared to myometrial cells and that TGF-β signaling promotes the production of versican, a critical ECM protein, specifically increasing the production of glycosaminoglycan (GAG) rich-versican variants and contributing to the excessive, disordered ECM characteristic of uterine fibroids.