It's not often that a new approach to treating disease reveals itself in a flash. Clarke's eureka moment came in 1996, while he was showing some University of Michigan medical students a slide of testicular cancer cells. Some of the cells were mature; some were in the immature form known as stem cells. At the time scientists were investigating stem cells as a possible source of cancer cures. What if, Clarke wondered, it were the other way around? What if stem cells were causing the cancer?
Many scientists believe that Clarke's guess was right, at least for certain tumors, and that his controversial findings could help turn cancer research upside down. Most cancer treatments target mature cells; if instead you focus on the cancer-causing stem cells, Clarke reasons, you should be able to shut down the process of malignancy before it goes too far.
Early studies on mice were promising, and in December the company Clarke founded to pursue this line of research, OncoMed, won the backing of GlaxoSmith-Kline - an investment that could grow, if its milestones are met, to $1.4 billion. The OncoMed approach has the potential to treat solid tumors in the colon, head and neck, lung, prostate, and pancreas. Human trials are set to start this year.
Last updated December 27 2007: 9:36 AM ET
