Abstract mRNA cancer vaccines demonstrate potential in clinical trials, but existing platforms struggle to boost antitumor efficacy without added cost or complexity. Here, we present a streamlined linear cap-independent mRNA (LciRNA) cancer vaccine platform, achieved by fusing a UPA protective sequence, composed of a viral exoribonuclease-resistant RNA (xrRNA) and a poly(A) binding protein (PABP) motif, to an optimized Enterovirus A internal ribosome entry site.