Treatment with Ochromycinone (STA-21), which is known as a small STAT3 inhibitor, showed approximately 75% improvement in the psoriatic phenotype, and the topical application of STAT3 inhibitor peptides showed anti-inflammatory effects that caused the down-regulation of IL-17A secretion in the imiquimod psoriasis mouse model [7]. This evidence concerns the gene IL17A and psoriasis.