CAV1 and breast cancer: Mercier et al (28) were the first to demonstrate that the Cav-1 protein is downregulated in human breast cancer (eight out of 11 patients showed a marked downregulation of Cav-1 protein expression in CAFs by western blot analysis), and observed that CAFs are more numerous in human breast cancer, with an elongated appearance and hyperproliferative when compared with NFs, suggestive of a transformed phenotype.