VCAM1 and endometriosis: Vitamin D and its metabolites show no relationship to UI, but endothelial activation/dysfunction and vascular integrity changes in VCAM-1, VEGF, sICAM-3, angiopoietin-1, and sTie-2 may contribute to UI, though the mechanisms through which they work require further evaluation; however, these protein changes have been associated with endometriosis, raising the suggestion that subclinical/undiagnosed endometriosis may have contributed to UI in these subjects.