From Science Magazine (AAAS)

The bad luck of cancer

    Jennifer Couzin-Frankel

Bert Vogelstein and Cristian Tomasetti of Johns Hopkins University have put forth a mathematical analysis of the genesis of cancer that suggests many cases are not preventable. Drawing on the published literature, they estimated the number of cells in an organ, what percentage of them are long-lived stem cells, and how many times the stem cells divide. With every division, there's a risk of a cancer-causing mutation in a daughter cell. Tomasetti and Vogelstein reasoned that the tissues that host the greatest number of stem cell divisions are those most vulnerable to cancer. When Tomasetti crunched the numbers and compared them with actual cancer statistics, he concluded that this theory explained two-thirds of all cancers.

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