PDCD1 and cancer: In the treatment of different cancers, PD-1 blockade was found to shift the immune response toward a proinflammatory Th1/Th17 response, as evidenced by increased levels of IFN-γ, tumor necrosis factor-alpha (TNF-α), IL-2, IL-6, and IL-17A which are the main players in the pathogenesis of different autoimmune skin diseases including LP, and to reduce the production of IL-5 and IL-13 by the Th2 cells [24].