FOXP3 Predicts Response to Treatment in Mycosis Fungoides.

BACKGROUND:The role of the T-regulatory cells (Tregs) marker forkhead box Protein 3 (FOXP3) in mycoses fungoides (MF) pathogenesis is unclear and the results of previous studies are inconclusive. OBJECTIVE:We aimed at ascertaining the possibility that FOXP3 expression may serve to predict MF stage and response to therapy. PATIENTS AND METHODS:Immunohistochemistry staining for FOXP3 was performed on 30 skin biopsies from patients with MF, and FOXP3 expression level was quantitatively graded. Disease stage, progression, and response to treatment were determined based on clinical and imaging evidence, and association with FOXP3 expression was assessed. RESULTS:FOXP3 expression in the dermis correlated with poor response to treatment (P=0.047). A negative non-significant relationship between epidermal FOXP3 expression and clinical stage severity was observed (P=0.17). CONCLUSIONS:Dermal FOXP3 expression in MF lesions could be used to predict response to treatment in patients with MF.