Potential breast cancer vaccine undergoing testing

A potential vaccine that would prevent the most deadly and aggressive type of breast cancer — triple-negative breast cancer — is undergoing testing.

The key protein for the vaccine, which would be a "holy grail" of cancer treatment, was found through "a matter of luck and tenacity in going through databases and looking for proteins," Dr. Vincent Tuohy said, almost like finding a needle in a haystack.

The vaccine works by jumpstarting the immune system and attacking any tumors that contain a specific protein that should not be present unless a woman is lactating.