In accordance, melatonin was found to regulate MMP gene expression and activity in many diseases, such that melatonin could protect against endometriosis by regulating TIMP-1/MMP9 and TIMP3/MMP3 in the peritoneal endometriosis mice model on degrading ECM and regressing the growth of the endometriotic lesion [59,60]. The gene discussed is MMP9; the disease is endometriosis.