American, British scientists win Nobel in medicine

An American scientist and two British researchers won the Nobel Prize in medicine Monday for discoveries about cell division that could open the way to new cancer treatments.

Leland H. Hartwell, 61, director of the Fred Hutchinson Cancer Research Center in Seattle; R. Timothy Hunt, 58, of the Imperial Cancer Research Fund in Hertfordshire, England; and Paul M. Nurse, 52, of the Imperial Cancer Research Fund in London will share the $943,000 prize, announced by Stockholm's Karolinska Institute.

The scientists were honored for their study of the cell cycle, the process by which a cell grows and divides. Along the way, the cell must duplicate its chromosomes and distribute them equally to the two new cells.

Cell division happens several billion times every day in the adult human body, and most of the time it goes fine. But when something goes wrong, it can lead to cancer, which is characterized by runaway cell division.

The Nobel winners all discovered genes and proteins that regulate the cell cycle.

The scientists' work is "a major contribution to our understanding of a basic biological process that has profound implications for cancer research," said Helen Piwnica-Worms, a cell cycle researcher at Washington University in St. Louis.

For example, scientists have already started testing drugs designed to influence the cell cycle and make cancer cells stop dividing or die. Also, careful study of which regulatory molecules are overactive or underactive in a patient's tumor could one day help doctors decide on the best treatment.