Abstract

 

Basically, cancer is a disease initiated by mutations in the genome. However, cancer is regarded not only as a genetical disease but also an immunological disease because cancer cells can be targeted by the immune system. The immune system recognizes mutated proteins as non-self, foreign antigens, so-called neoantigens, and exerts diverse effector functions to eliminate tumor cells. Anti-tumor immune responses resemble immune responses against viruses. In anti-tumor immune responses, CD8+ and CD4+ T cells are the main effector cells. In addition, dendritic cells (DCs) play a crucial role in the priming of CD8+ and CD4+ T cells, and natural killer (NK) cells also contribute to the anti-tumor immune responses.