CD274 and neoplasm: Once the average tumor volume of TC-1 reached approximately 75 mm3, mice were randomly assigned to the following groups: vehicle control, OX40 and 4-1BB agonists, PD-1, PD-L1, and CTLA-4 inhibitors, Xcl1-E6E7+mIL-9 plasmid DNA vaccine monotherapy, and Xcl1-E6E7+mIL-9 plasmid DNA immunization combined with OX40 and 4-1BB agonists and PD-1, PD-L1, and CTLA-4 inhibitors.