One of the most studied immunotherapeutic approaches is tumor vaccination; several clinical trials have exploited vaccination to elicit the immune response, using a peptide of an overexpressed or mutated protein, such as Mucin 1 (10), telomerase (11), survivin (12), or KRAS (13); or with whole tumor cells, such as GVAX, which is composed of granulocyte-macrophage colony-stimulating factor (GM-CSF)–secreting tumor cells (14, 15). The gene discussed is CSF2; the disease is neoplasm.