Dithranol treatment of plaque-type psoriasis increases serum TNF-like weak inducer of apoptosis (TWEAK)

Purpose: TNF-like weak inducer of apoptosis (TWEAK) mediates not only apoptosis, but also inflammation, cell growth and angiogenesis. The role of TWEAK in psoriasis remains unknown. The aim of the study was to assess serum levels of TWEAK in psoriatic patients before and after topical treatment with dithranol in relation to the clinical activity of the disease. Material and methods: Serum samples were collected from 40 patients with plaque type psoriasis before and after topical treatment with dithranol. The concentrations of serum TWEAK were measured by ELISA and next compared with 16 healthy controls. The data were analyzed with respect to Psoriasis Area and Severity Index (PASI). Results: Baseline serum TWEAK concentrations of psoriatic patients (685 +/- 166 pg/ml) were significantly greater compared to healthy controls (565 +/- 110 pg/ml). Topical treatment resulted in further increase in serum TWEAK (749 +/- 179 pg/ml; p < 0.01). In case of patients with initial serum TWEAK concentrations above the median, PASI after topical treatment was lower compared to the individuals with initial TWEAK below the median. Conclusion: According to the study, serum Tweak was increased in psoriasis patients compared with controls. Moreover, dithranol topical treatment caused further increase in serum TWEAK. Also, a higher effectiveness of topical treatment was observed in case of patients with higher initial TWEAK concentrations. The results suggest a potential role of TWEAK in psoriasis therapy. (C) 2016 Medical University of Bialystok. Published by Elsevier Sp. z o.o. All rights reserved.