Discovery could lead to better cancer immunotherapy

A type of white blood cell previously known only as a helper in the immune system appears also to be the instigator of the body's defenses against cancerous tumors. The discovery could lead to more effective cancer immunotherapy, a promising treatment which uses the body's own immune system, rather than radiation, to attack cancer cells. In an animal study, researchers found that a population of T cells called CD4-positive helper T cells helped start a chain of antitumor immunity defenses that allow killer cells to better infiltrate melanoma and breast cancer tumors.