CD8A and neoplasm: Rachidi et al. (2017) found that a protein called Glycoprotein A repetitions predominant (GARP) exists on the surface of platelets, which traps and activates Transforming growth factor-β (TGF-β). TGF-β is an immunomodulatory molecule that suppresses CD4 and CD8 T cells, allowing tumors to evade the immune system. Riesenberg et al. (2019) confirmed through a mouse model that the antiplatelet effect of aspirin can inhibit TGF-β signaling, thereby enhancing T cell function, and synergistically exerting anti-tumor effects with PD-1 blocker.