As the CD1a-DCs develop from monocytes under the conditioning of cytokines such as granulocyte-macrophage-colony-stimulating factor (GM-CSF), tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-4, and IL-1β [11,38], induction of CD1a-DCs may differ according to the tumor characteristics producing these cytokines. This evidence concerns the gene IL4 and neoplasm.