Aberrant caveolin-1 expression in psoriasis: a signalling hypothesis.

A preliminary retrospective immunocytochemical study was conducted examining the expression of caveolin-1 in skin biopsies resected from clinically defined psoriatic subjects. These pilot investigations revealed a dramatic down-regulation of caveolin-1 (a protein product of the caveolin supergene family known to regulate signal transduction events and cell cycle dynamics) in the hyperproliferative basal regions of the epidermis in all psoriatic biopsies examined when compared to normal control samples. These results lead us to hypothesise that caveolin-1 negatively regulates key signal transduction pathways in epidermal keratinocytes and through it's reduced expression in psoriasis, pertubations in keratinocyte cell signalling and abnormal cell differentiation ensue, events fundamental to the development of the psoriatic phenotype. Novel therapeutic strategies for the treatment of psoriasis based upon caveolin-1 protein can be envisaged.