Dendritic cells (DCs) secrete IL-23 to bind IL-23 receptor (IL-23R) presented on Th1, Th17, and Th22 cells, which in turn act on keratinocytes (Di Cesare et al., 2009; Raychaudhuri et al., 2015), ultimately leading to excessive proliferation of the cutaneous keratinocyte to form psoriasis (Chan et al., 2006). This evidence concerns the gene IL23R and psoriasis.