PHOX2B and neuroblastoma: However, CAR-T cells targeting intracellular proteins such as the cancer testis antigen NY-ESO-1, PRAME, and PHOX2B, a transcriptional regulator derived from neuroblastoma-dependent genes, have been shown to require an affinity of approximately 4 to 15 nM, rather than the TCR-like affinity range of KD = 1 to 100 μM (11, 12, 43).