Credit: Flinders Foundation
The development of oncogenes has been connected for the first time to circular RNAs by a team of researchers at Flinders University in Australia. Upon comparing blood samples of healthy children to those who later developed acute leukemia, researchers discovered that a specific circular RNA was present at much higher levels at birth in those who developed leukemia than those who did not.
“Circular RNAs can bind to DNA at many different locations across a range of cells. By binding to the DNA at specific sites, these circular RNAs cause a number of changes culminating in the breakage of the DNA which the cell must repair in order to survive,” says lead author Dr. Vanessa Conn. “This repair is not always perfect and this can result in small mutations, like a misspelt word within a book, or worse, very, very large and devastating mutations.”
These circular RNA, or circRNA, fuse at well-known leukemia hotspots however it was previously unknown what caused these mutations to form. The study, published in Cancer Cell, has shown that the overexpression of circRNAs in mouse leukemia models has resulted in similar chromosomal mutations at this known leukemia hotspot, potentially explaining the source of this mutation hotspot.
These gene mutations have long been used as a marker for treatment in patients as their presence would often indicate a worsened prognosis. With the discovery of the circRNA potentially being the cause of these mutations, the team of researchers intends to continue their research into their effects on cancer as well as their potential role in other diseases.