The immuno regulatory functions of C3a and C5a and their receptors (CR) has been characterized in cancer models, and it was found that number of myeloid-derived innate immune cells express C3aR and C5aR, including monocytes, macrophages, DCs, neutrophils, basophils, T cells, mast cells, and eosinophils [92–94]. This evidence concerns the gene C5AR1 and cancer.