The human immune system is naturally capable of killing cancer cells. But mutations and other abnormalities handicap or neutralize it, making the immune system insufficient and ineffective. Currently there is a lot of investment being made to study how to stimulate the immune system to kill cancer cells. However, there is evidence that in certain circumstances boosting the immune system actually encourages cancer cell growth. We’re trying to understand how this phenomenon works. Particularly, under the circumstances when a TCF-1 gene mutation is involved — the immune system, when stimulated, actually promotes the growth of lymphoma. We expect to learn how TCF-1 gene regulates the immune responses to affect the lymphoma development.