ARF1 and neoplasm: We also tested Arf1 inhibition and PD-1 blockage in MYC-ON mice and found that PD-1 blockage could further reduce the tumor number (Isotype/MYC-ON: 90.6 ± 19.1; PD-1/MYC-ON: 61.0 ± 14.2; Isotype/MYC-ON/GCA: 41.1 ± 19.0; PD-1/MYC-ON/GCA: 7.7 ± 7.6) and tumor weight and increase the lifespan but did not affect the body weight of these mice (Fig. 7i–k, and Supplementary Fig. 15c, d).