PECAM1 and cancer: Interestingly, all breast cancers, with the exception of the ER-negative tumours, expressed higher levels of WT1 versus that of the matched controls, whilst ER-positive cancers showed the most marked difference from controls, with higher of WT1-positive, CD31-positive, and WT1/CD31 double-positive cells, as well as higher numbers of both total and WT1-positive vessels (Suppl.