CD274 and neoplasm: As expected, the PD-L1 blockade alone markedly suppressed the growth of subcutaneous 4T1/EPB tumors, but the PD-L1 blockade with anti-PD-L1 antibody did not enhance the anti-tumor efficacy of UPs-4T1/EPB nanovaccine in the UPs-4T1/EPB-vaccinated mice (Supplementary Figures S6B–E).