In keratinocytes, previous studies have shown that the expression of DUSP2 and DUSP5 changed in response to an adalimumab treatment in psoriasis patients whereas arsenic, a human carcinogen that can cause squamous cell carcinomas (SCCs), could inhibit the expression of DUSP2 or DUSP14 [28,29]. This evidence concerns the gene DUSP2 and psoriasis.