CTLA4 and neoplasm: Such a regimen may include 4th generation (TRUCK) or 5th generation (+IL-2Rβ) CAR-Ts involved in dual-targeting of ErbB and MUC1, mitigating on-target, off-tumour toxicity, whilst also directing this immunotherapy towards immune checkpoint receptors (PD-1, CTLA-4) and the suppression of anti-tumour immunity, exerted by the tumour microenvironment, hence potential future focus on modulating CAF and TAM influences (already being appreciated in the design of current clinical trials; Table 1).