Human trials will begin soon for a very promising cancer treatment being developed at Stanford. There, researcher Irving Weissman and his team have developed a treatment capable of killing cancer cells while leaving healthy cells largely unharmed.
The new treatment acts on the protein CD47, a protein found on the surface of cancer cells that essentially says “don’t eat me” to a person’s immune system. CD47 tricks the immune system of someone with cancer into letting tumors continue to grow.
Weissman and his team developed an antibody to CD47 that prevents the protein from being produced in the body. In the absence of CD47, the immune system attacks and kills cancer cells.
The groundbreaking therapy has proven incredibly effective in animal testing so far. To test the treatment on human cancers, researchers implanted human cancer tumors in to mice. In the absence of treatment, these tumors would continue to grow in the mice. But this all changed when the CD47 antibody was used.
The new cell therapy cured or shrunk human strands of breast, ovary, colon, bladder, brain, liver, and prostate tumors during trials.
Of course, killing cancer cells isn’t the difficult part of treating cancer. The hard part is finding a treatment that kills cancer cells while keeping healthy cells alive. The CD47 antibody delivers here too.
Overall, the mice suffered from a brief period of anemia as their bodies reacted to the treatment. That’s it. The anemia occurs because the body’s blood cells use CD47 for the same “don’t eat me” purpose. With suppressed levels of CD47, blood cell levels temporarily drop. The body quickly reacts, though, and counters by producing more blood cells. Blood cell levels then return to normal. Given the havoc current cancer treatments like chemotherapy wreak on a patient’s body, this is a huge accomplishment.
The treatment has proven effective "on every single human primary tumor that we tested,” Weissman said. “We showed that even after the tumor has taken hold, the antibody can either cure the tumor or slow its growth and prevent metastasis.”
The early results are so promising that the California Institute of Regenerative Medicine has given the Stanford team a $20 million grant to continue its work. In January, Stanford announced that FDA-approved phase 1 human trials for the therapy are slated to begin midway through 2014.
Cancer kills 580,350 Americans each year – an average of 1,600 people a day. If the CD47 antibody proves even half as effective in human trials as it has been in animal testing, it’ll be a huge accomplishment.