Revealing the Origins of DNA Damage in Cancers
Half of all Canadians will develop cancer at some point in their lives, and one in four will ultimately die from the disease. These figures highlight the urgent need for better ways to prevent, diagnose and treat cancer.
Cancers often arise because mutations (DNA damage) enable cancer cells to grow and divide in an abnormal, uncontrolled manner. Mutations have several possible causes, including internal processes in our cells, inherited genetic abnormalities, and harmful environmental exposures. Some of these sources of DNA damage have been identified, but many more remain to be discovered.
Crucially, each source of DNA damage tends to create a specific pattern of damage that is statistically distinct. These molecular calling cards are essentially “mutation signatures.”
Dr. Kin Chan, Canada Research Chair in Molecular Basis of Cancer Mutagenesis, is deciphering the mutation signatures of processes and agents that are thought to play a role in how cancers arise. He and his research team use baker's yeast that has been genetically engineered for collecting large numbers of mutations when exposed to DNA-damaging conditions. After sequencing the yeast cells' DNA, they use computational methods to identify and analyze all mutations from the yeast models, then query human data to identify cancers with statistically matching signatures.
Chan’s work is revealing what causes DNA damage in cancers, and may inform policy-making to curb harmful environmental exposure. Ultimately, it may lead to more in-depth diagnoses and support personalized cancer therapies.