One potential concern with using APRIL-based CARs is that an ineffective cytotoxicity event following synapse formation between the T cell and the tumor cell could result in the amplification of a survival signal to the tumor cell based on signaling through BCMA and/or TACI; however, our pre-clinical data and others18 did not find any evidence of this hypothetical concern. This evidence concerns the gene TNFRSF17 and neoplasm.