One of cancer's nastiest tricks was discovered by biologist Irving Weissman at the Stanford School of Medicine almost 10 years ago. The protein--called CD47--is found on healthy blood cells, where it serves as a marker that tells your immune system that those cells shouldn't be attacked. Weissman discovered that that protein also appears in higher concentrations on leukemia cells, essentially putting a "Do not attack" flag on cells the immune system should be attacking. Recent research has shown that CD47 isn't just limited to blood cancers, it was found on all the tumors they tested.
The current study has shown that treating tumors on mice with anti-CD47 antibodies can slow the tumor's growth, or even cause it to shrink. The next step is to see how anti-CD47 treatments work in human trials.