Posted by 
Researchers at the European Bioinformatics Institute (EMBL-EBI), the University of Dundee and the Wellcome Sanger Institute have used human and worm data to explore the mutational causes of cancer their study shows that results from controlled experiments on a model organism—the nematode worm C. elegans—are relevant to humans, helping researchers refine what they know about cancer.
Cancer is caused by DNA mutations that can be triggered by a range of factors, like UV radiation, certain chemicals, smoking and errors during cell division. A cell recognises most of these mutations and corrects them through multiple repair mechanisms. However, DNA repair is not perfect, so it can leave certain mutations unrepaired or repair them incorrectly leading to changes in DNA.
Understanding the footprints of these mutational processes is an important step in identifying the causes of cancer and potential treatments. The DNA mutations in cancer cells were caused by a yin and yang of DNA damage and repair,” explains Moritz Gerstung, Research Group Leader at EMBL-EBI.
Studying a patient’s cancer genome is looking at the final outcome of multiple mutational processes that often go on for decades before the disease manifests itself. The reconstruction of these processes and their contributions to cancer development is like the forensic analysis of a plane crash site, trying to piece together what’s happened.
Previous research has shown that one of the first DNA repair pathways associated with an increased risk of cancer is DNA mismatch repair (MMR). The current study uses C. elegans as a model system for studying MMR in more detail. Assessing the kinds of mutations that arise when C. elegans is defective for one specific DNA repair pathway, it takes three days to propagate worms from one generation to the next, the process of studying how DNA is passed on is greatly expedited.
DNA mismatch repair is propagated for many generations and this allowed deduce a distinct mutational pattern, there is a resemblance between the most common signature associated with mutations in MMR genes in humans and the patterns found in nematode worms, this suggests that the same mutational process operates in nematodes and humans. These findings could lead to a better understanding of the causes of cancer and provide appropriate treatment.
haleplushearty.org