CircRNA-LNP vaccine suppresses the progression in orthotopic and metastasis B16 tumor model. (A) Timeline of the anti-tumor assay in orthotopic B16 tumor model, intramuscular vaccination (10 µg circRNA per mouse). (B) Tumor growth curves and (C) the survival curves of the three groups. PBS, PBS-LNP complex (n = 5); M1Ψ mRNAOVA-luc, M1Ψ mRNAOVA-luc-LNP complex (n = 6); circRNAOVA-luc, circRNAOVA-luc-LNP complex (n = 6). (D-F) Individual tumor growth curves of the mice from different groups. (G) Timeline of the anti-tumor assay in metastasis B16 tumor model, intramuscular vaccination (10 µg circRNA per mouse). (H) Statistical result of the H-2Kb/SIINFEKL tetramer-positive T cells in PBMCs seven days after the second immunization. PBS, PBS and LNP complex (n = 5); M1Ψ mRNAOVA-luc, M1Ψ mRNAOVA-luc-LNP (n = 5); circRNAOVA-luc, circRNAOVA-luc-LNP (n = 5). (I) Survival curve of mice after different treatments. **p < 0.01, ***p < 0.001.