News Release

Telomere length may be associated with risk of smoking-related cancers

Peer-Reviewed Publication

Journal of the National Cancer Institute

People with short telomeres, as measured in white blood cells, appear to be at an increased risk for certain cancers, according to a study in the August 20 issue of the Journal of the National Cancer Institute. The study found that, compared with people with longer telomeres, people with shorter telomeres had a higher risk for bladder, head and neck, lung, and renal cell cancers--cancers that are associated with cigarette smoking.

Telomeres cap the ends of chromosomes and prevent them from degrading, fusing, or recombining abnormally--events that may lead to cell death. Although telomere shortening is associated with aging, studies have shown that telomere length can vary considerably among people of the same age. The observation raises the possibility that individuals with shorter telomeres are at an increased risk of cancer, as short telomeres have been associated with increased risk of intestinal and epithelial cancers.

To examine the association between telomere length and risk of cancer, Xifeng Wu, M.D., Ph.D., of The University of Texas M. D. Anderson Cancer Center, Houston, and colleagues measured telomere length in peripheral blood lymphocytes (white blood cells) of patients participating in four ongoing studies of head and neck, bladder, lung, and renal cell cancers.

The researchers found that patients with these cancers had statistically significantly shorter telomeres than patients without cancer and that increased cancer risk was associated with progressively shorter telomeres. Moreover, factors such as age, gender, and smoking status appeared to influence the effect that short telomeres had on cancer risk. For example, people who smoked and had short telomeres had a substantially greater risk for tobacco-related cancers than people who never smoked and had short telomeres or people who smoked but had longer telomeres.

The researchers acknowledge that they measured telomere length in a surrogate tissue, peripheral blood lymphocytes, not in cancer cells, and that cancer cells have different telomere dynamics. "Future research should focus on the associations of telomere dynamics, cell cycle checkpoints, apoptosis, the activation of telomerase, and DNA repair capacity, ultimately, with the goal of enhancing our ability to identify high-risk subgroups," they write.

In an accompanying editorial, Kwok-Kin Wong, M.D., Ph.D., and Ronald A. DePinho, M.D., of the Dana-Farber Cancer Institute and Harvard Medical School in Boston, point out that many studies have started to explore the usefulness of determining telomere length in more accessible white blood cells rather than in diseased tissue.

They say that the current study "raises a number of intriguing possibilities that relate to how telomeres influence tumorigenesis in the aged." However, they caution that it is too early to link telomere length in white blood cells with the risk of cancer. They say that the new findings warrant a large prospective epidemiologic study designed to determine whether telomere length, measured in early life or at least before the onset of cancer, is associated with the risk of developing cancer.

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Contact: Laura Sussman, The University of Texas M. D. Anderson Cancer Center, 713-792-0655, lsussman@mdanderson.org.

Editorial: William Schaller, Dana-Farber Cancer Institute, 617-632-5357, william_schaller@dfci.harvard.edu.

Wu X, Amos CI, Zhu Y, Zhao H, Grossman BH, Shay JW, et al. Telomere dysfunction: A potential cancer predisposition factor. J Natl Cancer Inst 2003;95:1211–18.

Editorial: Wong K, DePinho RA. Walking the telomere plank into cancer. J Natl Cancer Inst 2003;95:1184–6.

Note: The Journal of the National Cancer Institute is published by Oxford University Press and is not affiliated with the National Cancer Institute. Attribution to the Journal of the National Cancer Institute is requested in all news coverage.


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