In vitro studies with endometriotic epithelial cells derived from patients with endometriosis have shown that 1 mM of melatonin blocked 17β-estradiol-induced migration, invasion and epithelial–mesenchymal transition (EMT) through the upregulation of the Numb endocytic adaptor protein (Numb) and the low activity of the neurogenic locus notch homolog protein 1 (Notch1) [133]. Here, NUMB is linked to endometriosis.