Gene Variation Links Lower Bladder Cancer Risk, Long Chromosome Tips

Like the plastic tips on shoelaces, telomeres sit at the end of chromosomes, protecting them from unraveling telomeres are protective, preventing harmful damage to DNA on the chromosome and inappropriate fusion with other chromosomes.

These caps grow shorter over time and as that occurs, they become associated with diseases of aging, such as Alzheimer's disease, stroke and some cancers.

Evidence has indicated that there's an inherited factor that helps determine telomere length and that short telomere length is a risk factor for cancer. No one had ever connected the two, until now.

Jian Gu, Ph.D., assistant professor in MD Anderson's Department of Epidemiology, and colleagues have found that a single point of variation along the genome on chromosome 14 is associated with a 19% decrease in bladder cancer risk and, separately, with longer telomeres.

Gu presented results at the American Association for Cancer Research 102nd Annual Meeting 2011. AACR also selected the research for highlighting at a news conference Saturday.

AACR President Elizabeth Blackburn, Ph.D., from the University of California San Francisco also spoke about the importance of Gu's research. Blackburn shared the 2009 Nobel Prize for Medicine or Physiology for her part in the discovery of telomeres and the enzyme telomerase.

Telomere length is caused by both genetic and environmental factors, such as smoking, chemical exposure or chronic stress.

"This research is really important because as we think about better treatment for cancer, we need to take into account its very early processes and risk factors," Blackburn said.

"When you look at the health burden -- both the human burden and economic burden -- cancer prevention, to me, is inescapable. We have to do prevention and interception. Research now is really taking us earlier and earlier into cancer progression," Blackburn said.

"Understanding the complex genetic regulation of telomere length and its relation to the causes of bladder and other types of cancer will help develop therapies or lifestyle changes to reduce cancer risk," said Xifeng Wu, M.D., Ph.D., professor and chair in the Department of Epidemiology in MD Anderson's Division of Cancer Prevention and Population Sciences.

MD Anderson news release on the presentation: Genetic Variation Cuts Bladder Cancer Risk, Protects Chromosome Tips.