Recent studies have demonstrated a Th2 cytokine-prone inflammation in the lesional skin of atopic dermatitis. The lesional infiltration of IL-17-producing immune cells is also evident, but the implication of their infiltration remains elusive in AD. Using an in vitro scratched keratinocyte model, we investigated the effects of "scratch" on the CCL20 production, which is a cardinal chemokine for CCR6+IL-17-producing cells. We found that the scratch injury selectively upregulated the CCL20 production from an in vitro keratinocyte sheets. Notably, IL-4 and IL-13 did not affect the scratch-induced CCL20 production. These results suggest that the infiltration of IL-17-producing cells may be attributable to scratch-induced CCL20 production, but not to the Th2-prone milieu.

Apalutamide, an oral androgen receptor antagonist, has been used to metastatic castration-sensitive prostate cancer from 2019 in Japan. It has been known that treatment with apalutamide frequently develops skin rash, which occurs at 2-3 months after starting the therapy. Although skin rash was most commonly described as maculo-papular rash, the details about skin manifestations have been unclear. Two Japanese men developed widespread, pruritic, erythematous scaly rash on the trunk and the extremities with peripheral eosinophilia after 6 and 9 weeks after starting therapy with apalutamide. Histological examination showed interface dermatitis with vacuolar change, exocytosis of lymphocytes, and Civatte bodies. After the discontinuation of apalutamide, the erythema gradually improved. Apalutamide should be taken in consideration as a causative drug of lichenoid drug rash.