CTLA4 and neoplasm: Intratumoral heat-iMVA alone in syngeneically transplanted PRC2-loss AT3 (sgEed) tumors only mildly retarded the tumor growth; however, i.t. heat-iMVA, when combined with anti–PD-1 and anti-CTLA4 ICB treatment, significantly reduced tumor growth (Figure 8, C and D, and Supplemental Figure 8A).