SMAD3 and endometriosis: Although functional research on the effects of disturbances in the expression pattern of the studied genes and miRNA in the disease mechanisms, especially in the induction/progression of endometrial EMT, as well as a comprehensive insight into this system, will require analysis at the protein level, these data, including previous evidence, suggest a role of TGF-β1, SMAD3 and ILK, as well as the regulator miR-21, in the pathogenesis of endometriosis.