Arnold Levine, a molecular biologist, and an authority on the molecular basis of cancer, gave one of the KITP 2005 Public Lectures on “Genetic Predispositions for Cancer in Humans.” He also served as co-director, with Boris Shraiman, of a February 2005 mini-program on “Growth, Death and Aging.” Why is a cancer expert giving a public lecture and leading a research program at an institute for theoretical physics?
Levine has two professorial appointments at two different institutions with distinctly different characters: the School of Natural Sciences at the Institute for Advanced Studies (IAS) in Princeton, N.J., where he directs the Center for Systems Biology, and the Cancer Institute of New Jersey at the Robert Wood Johnson School of Medicine in nearby New Brunswick. His theory group is located at the former; and his research labs, at the latter.
Best known as co-discoverer of p53 (a key tumor suppressor protein), Levine is pioneering with his IAS group a modus operandi for theoretical biology. The IAS group consists of physicists, mathematicians, computer scientists, and a physical chemist. Two of the physicists were trained as string theorists.
“For the first time,” Levine said, “biology is working a lot like physics — with theorists making hypotheses and predictions, and biologists going back to the laboratory to test those predictions. That approach is entirely new to biology. Biology hasn’t had great theorists, other than Darwin. The field begins with him. It’s interesting that a field not known for theory should have begun with a theorist.”
As described in his public lecture, Levine’s research now focuses on genetic polymorphisms. Unlike mutations, polymorphisms represent small genetic differences among people. With the completion of the sequencing of the human genome in 2000, “We now know,” said Levine, “that any two people are 99.9 percent identical. But the other 0.1 percent accounts for three million differences. We want to know which of those differences might predispose a person to cancer. So far, we have been able to identify three such structural changes. One small change we found [published in Nov. 2004 Cell] can give rise to cancer at an early age. That change exists in 11 percent of the Caucasian population, and some subset of those will be developing cancer at a young age.”
Identifying such genetic susceptibilities to disease will enable vulnerable people to undergo routine diagnostic tests to screen for and to detect cancer “early, when treatments are most effective, and cure is a real possibility,” according to Levine.
“Our task,” said Levine, “is to design methods to probe three billion bits of information. That task requires algorithms for manipulating these huge databases. The more quantitative sciences have developed the statistical and analytic tools we are now applying to biology. But their contributions go well beyond informatics. I have seen in this workshop, here at the KITP, that physicists come up with novel questions that do not occur to biologists."
“I see the emerging role for physics in biology as providing a new research paradigm with dynamic interaction between theory and experiment,” said Levine.
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Click above to play Genetic Predispositions for Cancers in Humans or watch at http://online.kitp.ucsb.edu/online/plecture/levine1/