An inverse correlation was observed between the level of expression of the SMAD3 and ILK genes and the stage of the disease; however, in the case of the ILK gene, only a negligible downward trend in ILK expression was observed in the group of patients with stage IV vs. stage III of endometriosis (p = 0.086857, Mann–Whitney U test). Here, ILK is linked to endometriosis.