CSPG4 and endometriosis: Although HEP showed higher epithelial expression in normal endometrium, the logistic regression analysis identified that relatively higher expression levels of CSPG4, CS-56, and HEP in the epithelium were predictive of endometriosis, while higher keratan sulfate and hyaluronic acid expression in both epithelium and stroma were associated with a reduced likelihood of endometriosis.