POU5F1 and endometriosis: Given the fact that serum TGF-β levels are up-regulated in patients with endometriosis [19, 21, 22], the positive correlations among OCT4, TGF-β RI, and migration-related genes suggested that TGF-β/TGF-β RI may play a crucial role in the transcriptional regulation of OCT4 and migration-related genes in human endometriotic tissues.