How a genetic parasite contributes to cancer development

Our DNA is a history book, telling the story of who we are and how we arrived here over hundreds of millions of years of evolution. Our genomes contain many ancient remnants of the past, including sections of genetic code known as “L1 retrotransposons” that have recently become of great interest to cancer researchers. These ancient bits of DNA are genetic parasites, hitching a ride on our DNA and able to “copy and paste” themselves throughout our genome. 

L1 retrotransposons play a role in cancer but little is known about how they act to promote and maintain cancer. In over 50 per cent of cases, the cancer genome contains more L1 retrotransposons then DNA from healthy cells, and the more the cancer genome contains, the more severe the disease seems to be. 

The piece of genetic code contained within L1 retrotransposons carry the instructions that cells use to build two different proteins. And it’s only by interacting with other proteins in the cell that these proteins can make cancer cells grow and divide. Dr John LaCava and his team based at the Rockefeller University in New York, USA, are trying to unravel the network of interactions between these proteins to get a grasp of how L1 retrotransposons drive cancer. It is these discoveries that could open up new avenues for improving diagnosis and treatment of cancer.