Does the length of someone's telomeres predict their risk of cancer?
Telomeres -- those fancy structures that protect the tips of chromosomes -- have been a hot area of scientific study for some time. In 2009, three biologists shared a Nobel Prize for their telomere research. The gradual shortening of these structures could be one reason why cells age and die. (Here's a Times article about telomeres.)
Now, in a study just published in the Journal of the American Medical Assn., Austrian researchers reported that people with shorter telomeres are more likely to develop cancers.
The researchers measured telomere length in the leukocytes (a type of white blood cell) of 787 people in 1995. The scientists sorted the people into three groups based on their blood cells' telomere length: longest, middle and shortest.
Over the next 10 years, 92 developed cancer. The researchers found that the risk of cancer was twice as high in the middle-length group compared with the longest-length group. It was three times higher in the shortest-length group compared with the longest-length group.
This makes sense, the authors wrote, given that telomeres keep chromosomes stable and cancer is associated with rearrangements of chromosomes that can result in some genes working overtime and others not at all -- causing cells that shouldn't proliferate to begin multiplying out of control.
Here's a write-up of the research at HealthDay News. Researchers are waiting for the findings to be confirmed before they get too excited about it, the article notes.
And here's an abstract of the article in JAMA. As with many medical journals, you can't look at the entire article for free.
Cancer-telomere research is an active field. Some scientists think that if we can interfere with the malignant cells' ability to keep lengthening their telomeres so they can keep dividing indefinitely, it might prove a useful therapy. If that seems at odds with the finding above -- and if the above finding holds up, of course -- it's probably because the events that give rise to a cancer are different than what happens after a cancer cell has gotten going.
-- Rosie Mestel