Caveolin-1 was first thought to have tumour suppressor properties (Razani et al, 2001a, 2001b; Hnasko and Lisanti, 2003), based on the finding of an arguable inactivating point mutation in CAV1, the silencing of CAV1 gene expression by promoter hypermethylation in breast cell lines and prostate tumour samples (Engelman et al, 1999; Hurlstone et al, 1999; Cui et al, 2001) and the apparent downregulation of CAV1 in breast cancer (Chen et al, 2004; Park et al, 2005). This evidence concerns the gene CAV1 and breast carcinoma.