A vaccine injected into a tumor triggers the immune system to kill cancer, a new study in mice confirms. Stanford researchers have now begun seeking human patients who want to help test this approach. The research behind this potential new cancer treatment was published Wednesday in Science Translational Medicine. Cancer vaccines work a bit differently than a vaccine against the measles or the flu. Those shots are meant to train an immune system to target an infection before the virus or bacteria arrives. Cancer vaccines, however, are given after a person is diagnosed. This shot ... combines two components: a short piece of DNA molecules that can stimulate the immune system to create greater quantities of a receptor called OX40 and a protein that sticks to those receptors, prompting the immune cells to attack the tumor. [Study co-author Dr. Ronald Levy] and his colleagues tested their vaccine in more than 90 mice, some with a tumor transplanted into them and others that were genetically primed to develop cancer. However, the next step in this research will go well beyond mice. Levy and his colleagues have begun looking for about 15 people with lymphoma to test the vaccine in a clinical trial. If the trials are successful, he believes it could help people with a wide variety of cancers. "I don't think there's a limit to the type of tumor we could potentially treat, as long as it has been infiltrated by the immune system," he stated.