New player in cancer risk

From Chicago, at a meeting of the American Society of Clinical Oncology

A newly discovered category of RNA could play an important role in cancer, researchers announced.

This new RNA type is distinct from microRNAs, snippets of genetic material that are also known to influence a person’s risk of developing tumors. The discovery presents an unexplored form of genetic involvement in cancer that could lead researchers to a better understanding of the disease, says George Calin of the M.D. Anderson Cancer Center in Houston. The new, as-yet-unnamed RNAs “are involved in cancer to the same degree as microRNAs,” he says.

The conventional role of RNA is to translate the code in DNA into proteins, which in turn do most of the work in a cell. Like microRNAs, this new class of RNA is not involved in manufacturing proteins, but instead influences the activity of other genes.

Calin and his colleagues found that about 10 percent of patients with colorectal cancer or leukemia had mutations in one of the new RNAs. Among people without cancer, none had the same mutations, showing a strong link between the mutations and cancer risk. “These are another class of noncoding RNAs that could be involved in cancer predisposition,” Calin says. “This, I think, is an important idea for understanding the genetic basis of familial cancers.”