T cell mulfunction in the tumor environment

The cancer microenvironment may be envisaged as a battlefield of a fight between the host's immune system and the tumor. An army of T lymphocytes, which are trained to combat bacterial and viral infections, is mobilized to attack the tumor, but most of the times succumbs to its powers and lose the war. A major reason for this failure is the unique composition of the cancer microenvironment, which is shaped by the tumor in favor of its progression. The immunosuppressive environment of the tumor makes it a hard place for T cells to exert their otherwise powerful effector functions. The study of the cancer microenvironment yields important insights into the nature of the tumor protective shields surrounding the tumor. Recent studies bring new prospects for intervention therapies based on recruitment and activation of T cells at the cancer microenvironment.