The Steroid Receptor Coactivator-1 (SRC-1) isoform/Matrix Metalloproteinase-9 (MMP-9)/Estrogen Receptor beta (ERβ) axis has been identified as a key driver of endometriosis by inhibiting apoptosis and promoting inflammatory responses within endometriotic lesions[23,24]. This evidence concerns the gene ESR2 and endometriosis.