Simvastatin and related statins, such as compactin, are able to inhibit the constitutive
expression of inducible/repressible keratin genes such as K6a and K17. This effect is due to
the reported ability of statins to inhibit STAT1 expression (Lee et al., 2007). The
constitutive K6a promoter activity is dependent on STAT1 and blocked by simvastatin or siRNA
against STAT1. This STAT1-dependent constitutive expression of K6a, is independent of JAK
(Janus family of kinases).
Thus simvastatin is capable of down-regulating both the constitutive and interferon-inducible
expression of PC-related keratins such as K6a and K17. Therefore, this class of molecule has
potential for the treatment of PC or related inherited disorders where the causative mutation
resides in an inducible/repressible keratin gene such as K6a or K17.
Simvastatin or other statins approved for human use might be delivered either orally, as is
currently the case for cholesterol-lowering treatment or, if higher therapeutic doses are
required in skin for reduction of hyperkeratosis in PC or in related keratinizing disorders,
this might be achieved by topical formulations.