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 tumour cells often have abnormal numbers of chromosomes supports this theory, and two papers appearing the 13 October 2005 issue of Nature (Vol. 437, No. 7061, pp. 1043-1047 & 1038-1042) provide new, more direct evidence to support this.
David Pellman and colleagues tested the theory by blocking cell division in cells that also lack the tumour 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 tumours in mice, and these tumours showed genomic instability similar to many human cancers.
Another study by Qinghua Shi and Randall King shows how tetraploid cells can arise. The authors show that inaccurate segregation even of a single pair of chromosomes - an error that does occur every so often - 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.
David Pellman (Children's Hospital, Harvard Medical School, Boston, MA, USA)
Randall W. King (Harvard Medical School, Boston, MA, USA)
(C) Nature press release.
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