Immunotherapies are the best cancer fighting tools today, but they're expensive. They're customized to each patient, activating the person's immune system to kill cancer cells.

Now there's an exciting alternative that's not only cheaper but may activate any person's immune system against cancer, a sort of universal cancer vaccine. Researchers have been injecting tumors with viruses and a variety of molecules in hopes of finding ones that would activate the body's immune system to kill cancer cells.

Though they had found some that work in animals, none worked in humans until a group of scientists at Stanford decided to test twenty molecules they believed might work. They induced tumors in mice by injecting them just below the skin in two spots on the abdomen. Once the tumors started growing, they injected the twenty molecules alone or in combinations into one of the two tumors.

They hit the jackpot with one pair of molecules. One is a small DNA molecule called a CpG and the other is an antibody called OX-forty. Both stimulate the immune system to enhance its cancer fighting activity. Alone, the two molecules had little effect on the tumors, but injected together, the injected tumors disappeared in under ten days. Even the uninjected tumors in the same animal disappeared within twenty days.

Amazingly, eighty-seven of the ninety mice tested were cured of their cancers. Even in three mice where the cancer returned, the tumors regressed when they were re-injected. A clinical trial is already planned with fifteen cancer patients. How amazing if the trials work and a cancer vaccine becomes a reality.