For endometriosis, curcumin alleviates symptoms through its anti-inflammatory properties by inhibiting cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2), reduces angiogenesis by downregulating vascular endothelial growth factor (VEGF), and induces apoptosis in endometrial cells by modulating the B-cell lymphoma 2/Bcl-2-associated X protein (Bcl-2/Bax) ratio [83]. This evidence concerns the gene PTGS2 and endometriosis.