Study Findings: Cancer Can Begin in Sudden Catastrophic Event

A study in the January 7, 2011 issue of the journal Cell finds that cancer cells, conventionally thought to develop exclusively over longer periods of time can also begin in a single event, "whereby tens to hundreds of genomic rearrangements occur in a one-off cellular crisis."

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The causal factors are not known, but some possibilities include ionizing radiation, "well-known to induce dsDNA breaks," or, because most examples of this occurrence involve regions extending to the telomeres, the damage could be a result of the "breakage-fusion-bridge cycle associated with telomere attrition."

Cancer formation could be related to copy number changes, with the new structure omitting tumor suppressor genes or containing an "increased copy number (amplification) of genes promoting malignant cellular processes."

The study reports that this episode, termed "chromothripsis" by the authors, accounts for 2% to 3% of all cancers across all tumor types, and that evidence of these events are particularly prevalent in bone cancers (up to 25%).

Twenty patients with bone cancers-9 with osteosarcoma and 11 with chordoma-were screened to detect rearrangement. Five were shown to have cells which contained the hallmarks of chromothripsis.

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