Abnormal
histone modification by
histone deacetylases (HDACs), including HDAC1 and
sirtuin 1 (
SIRT1), has been reported to play an important role in the pathogenesis of
psoriasis by altering cell proliferation, differentiation, and
inflammation. However, findings on the expression level of HDACs in psoriatic skin lack consistency. We assessed the expression of HDAC1,
SIRT1, p63, and
proliferating cell nuclear antigen (
PCNA) in skin tissues from 23 patients with
psoriasis (15 with plaque
psoriasis and eight with guttate
psoriasis) and five healthy individuals using immunohistochemistry, and analyzed their associations with clinical phenotypes of the disease. The expression of HDAC1 and keratinocyte proliferative markers, such as p63 and
PCNA significantly increased, whereas that of
SIRT1 decreased in the basal layer (p < 0.05) of the patients with
psoriasis compared to those in healthy controls. Among the patients with
psoriasis, expression of HDAC1, p63, and
PCNA was significantly higher in plaque
psoriasis than in guttate
psoriasis. There was no significant differences in the level of
SIRT1 between the two clinical phenotypes. The findings of this study suggest that histone modifications are involved in the pathogenesis of
psoriasis and may contribute to the formation of clinical phenotypes.