Ribosomal protein S19 (RPS19), upon release from dying tumor cells, interacts with C5aR1 expressed on MDSCs, promoting its recruitment to tumors, the generation of Tregs, the production of immunosuppressive cytokines (including TGF-β), and the reduction of CD8+ T-cell tumor infiltration (99). This evidence concerns the gene C5AR1 and neoplasm.