As cancer vaccines, mRNA encoding cytokines, such as Interleukin-12 (IL-12), IL-27 [221], IL-23, IL-36γ [222], and INF-α [223]; antigens, such as OX40L [219], OVA [224], cytokeratin 19 (CK19) [225], and MUC1 [226]; or antibodies that block immune checkpoints, such as anti-PD-1 and anti-PD-L1 [227], can be used (see (2) in Figure 9). Here, PDCD1 is linked to cancer.