The levels of angiogenin, CD105, ICAM-1, CXCL10, leptin, lipocalin-2, MMP-9, osteopontin, RBP4, PAI-1, ABP, CD31, TIM-2, and VCAM-1 were higher in the endometriosis group than in the control group. Here, RBP4 is linked to endometriosis.