The in vivo effect of luteolin shows that the intraperitoneal injection of this flavone (50 mg/kg) in male BALB/c mice, previously psoriasis-induced with imiquimod cream, reduced the psoriatic area and severity index (PASI), histological severity, and HSP90β and HSP90α expression in the psoriatic skin-lesions of experimental animals. The gene discussed is HSP90AB1; the disease is psoriasis.