A new study of prostate tumors has shown that a gene, FOXO3, suppresses activation of cells related to immunity and thus leads to a reduced immune response against a growing cancer. One of the main problems in treating cancer by vaccine or immunotherapy is that tumors often evade the body’s immune response — and one of their tricks is to create an environment where immunity is inhibited or suppressed. By identifying a gene that makes immune cells suppressive, the researchers may have found a new target for enhancing immune responses to cancer tumor cells. The study, by scientists from the National Cancer Institute (NCI), part of the National Institutes of Health, appeared online March 23, 2011, in the Journal of Clinical Investigation, and in print April 1, 2011.