This condition is autosomal dominant and is linked to defects in KRT17 gene, which instructs the production of keratin 17
. However, some cases of steatocystoma multiplex occur sporadically with no mutation in the KRT17 gene; in them, the cause is unknown.
(4) Keratin 17 is expressed in pilosebaceous ducts, and EVHC have been observed in patients with other lesions involving the pilosebaceous duct--particularly infantile milia and steatocystoma multiplex.
(1) They are sometimes clinically hard to distinguish from EVHC, and both are associated with keratin 17 gene mutations and type 2 pachyonychia congenita.
Due to their different origins in the pilosebaceous unit, SM and EVHC cysts also differ in the classes of keratin found in their walls; while both cysts express keratin 17
, only steatocystomas demonstrate expression of keratin 10 .
(K17), a protein previously believed to provide only mechanical support for cancer cells, appears to play a crucial role in degrading a key tumor suppressor protein in cancer cells called p27.
Steatocystoma multiplex is also known as epidermal polycystic disease and sporadic or familial disorder (autosomal dominant mutation in keratin 17) .
[1.] Covello SP, Smith FJ, Sillevis Smitt JH et al: Keratin 17 mutations cause either steatocystoma multiplex or pachyonychia congenita type 2.
Coulombe, "Keratin 17 promotes epithelial proliferation and tumor growth by polarizing the immune response in skin," Nature Genetics, vol.
Wevers et al., "Up-regulation of keratin 17 expression in human HaCaT keratinocytes by interferon-y," Journal of Investigative Dermatology, vol.
Dang et al., "IL-17A upregulates keratin 17 expression in keratinocytes through STAT1- and STAT3-dependent mechanisms," Journal of Investigative Dermatology, vol.
Shi et al., "The pro-inflammatory cytokine il-22 up-regulates keratin 17 expression in keratinocytes via stat3 and erk1/2," PLoS ONE, vol.