APC (~80%–90%), TP53 (~50%–60%), and KRAS (~40%–50%) are the three most frequently mutated genes in CRC, collaborating to drive tumor progression.14–16 To investigate their respective roles in tumor immune evasion, we employed genetically engineered mice carrying conditional null alleles of Apc allele (Apcfl/fl), p53 (Trp53fl/fl, hereafter p53fl/fl), and mutant Kras (LSL-KrasG12D, hereafter KrasG12D). The gene discussed is KRAS; the disease is neoplasm.