Researchers report progress in the search for a "Holy Grail" cancer drug.

FOX News Radio's Chris Foster reports:

Researchers at Stanford University say the drug works by blocking a protein called CD47. That protein tells the immune system, do not attack, and cancer cells make a lot of it.

Those researchers say the antibody they've used in mice given human cancers has forced their immune systems to kill all kinds: breast, ovary, colon, bladder, brain, liver and prostate.

A side effect is that the immune system also attacks healthy cells, in the short-term. The next step: advance the research from mice, to human safety testing.

Chris Foster, FOX News Radio.

Editor's Note: The research was published Tuesday on the website of the Proceedings of the National Academy of Sciences.