Cancer Research UK-funded scientists have discovered that stretches of human DNA can actually help viruses infect people and trigger cancer-causing diseases, according to a study published in Nature Cell Biology.
The researchers discovered that viruses can exploit the body's DNA--hindering its antiviral immune response and allowing infection to take hold more easily. They demonstrated this phenomenon with the Kaposi sarcoma herpesvirus, which causes the cancer Kaposi Sarcoma, and with the herpes simplex virus, which causes cold sores.
The immune system uses multiple ways to prevent or clear infection. But viruses have also evolved highly sophisticated countermeasures to escape from the human immune defense. The team has discovered that viruses exploit tiny molecules derived from human DNA called microRNAs to make cells more susceptible to viral infection. MicroRNAs are mostly found in parts of the human genome that do not generate proteins--initially thought to be "junk DNA."
"The viruses we tested have evolved with humans for millions of years and use a variety of biological tricks to establish life-long and mostly harmless infections. We discovered that it is likely that other viruses--which can cause diseases including cancer exploit the tiny molecules present in everyone's DNA--called microRNA--to turn cells into a viral 'hotel' which they can check into, to cause infection and spread," says study author Dimitris Lagos.
"We are investigating microRNAs as future therapeutic targets, and targeting cellular microRNAs could be a potential way to prevent or treat cancer-causing infection from viruses," adds lead author Chris Boshoff in a statement.