Immunoediting

Immunoediting is the progressive, immune-mediated depletion of the most readily recognized cancer cells from a tumor population, which shifts the composition of the surviving population toward less visible variants. It is why the phenotype of a tumor growing under immune pressure can differ systematically from that of the same tumor growing in an immunodeficient host.

Comparing tumors in immunocompetent and immunodeficient animals is therefore a standard way to detect which cancer cell properties the immune system selects against. A cancer vulnerability is conventionally expected to be both required for disease progression and specific to cancer cells; immune recognition achieves such specificity combinatorially, by reading several features of a target cell at once, so a feature that is not itself unique to cancer can still serve as an index of dysregulation when it appears alongside a permissive set of surface ligands.