DURHAM, NC Newly identified mutations in a gene that makes cells immortal appear to play a pivotal role in three of the most common types of brain tumors, as well as cancers of the liver, tongue and urinary tract, according to research led by Duke Cancer Institute.
The finding, published Monday, March 18, 2013, in the journal Proceedings of the National Academy of Sciences, provides a long-sought answer to how some malignant cells are able to proliferate, while normal cells peter out and die.
This key to immortality involves telomeres, the end tabs that protect chromosomes from sticking together or fraying. As normal cells divide, the telomeres gradually grow shorter until they become so short the cell stops dividing and it expires. An enzyme called telomerase serves as a sort of growth factor, temporarily maintaining the length of the telomeres and enabling the cell to continue proliferating.
Scientists have recently learned that mutations of the so-called TERT promoter gene, which controls the instructions for making the telomerase enzyme, is involved in some cancer tumors. It appears that a mutation of the TERT promoter gene essentially creates a constant growth spurt so that the telomeres never shorten, and the cells can divide forever. Earlier this year, the process was described as a leading contributor to melanomas and a small number of other tumors.
The current research expands those findings by analyzing more than 1,200 tumors across 60 different types of cancer. Led by Hai Yan, M.D., PhD, a professor of pathology and investigator with Duke's Preston Robert Tisch Brain Tumor Center, the research team includes collaborators at Johns Hopkins and multiple other institutions.
The researchers found almost no TERT promoter mutations in many major cancer types, including breast and prostate malignancies, suggesting that some yet-unknown factor is causing the telomeres to elongate and promote cell immortal
|Contact: Sarah Avery|
Duke University Medical Center