Double-trouble: Cells with duplicate genomes can trigger tumors
Studies appear in Nature
The idea that a failure of proper cell division produces genomic instability and promotes the development of cancer was first proposed by German biologist Theodor Boveri in 1915. The fact that tumor cells often have abnormal numbers of chromosomes supports this theory, and two papers published by Harvard Medical School researchers provide new, more direct evidence to support this.
David Pellman, Harvard Medical School associate professor of pediatrics at Dana-Farber Cancer Institute and Children's Hospital Boston, and colleagues tested the theory by blocking cell division in cells that also lack the tumor suppressor gene p53, to generate tetraploid cells - cells that contain a double quota of chromosomes. Compared to their diploid counterparts, which have a normal set of chromosomes, tetraploid cells were more prone to generate tumors in mice, and these tumors showed genomic instability similar to many human cancers.
Another study by Randall King, HMS assistant professor of cell biology, shows how tetraploid cells can arise. He shows that inaccurate segregation even of a single pair of chromosomes - an error that does occur randomly – will halt cell division and produce tetraploid cells. Together, these papers lend experimental support to Boveri's ideas that errors in cell division contribute to the development of cancer.
Source: Eurekalert & othersLast reviewed: By John M. Grohol, Psy.D. on 21 Feb 2009
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