Published in the prestigious journal EMBO Reports, the researchers found that the DPP9 enzyme regulates a protein known as BRCA2, a well-known suppressor of tumour growth.
The finding suggests that targeting DPP9 could be an effective therapeutic approach to tackling cancer, the second leading cause of death globally.
“BRCA2 suppresses tumours by enhancing DNA repair,” said Professor Mark Gorrell, Head of the Liver Enzymes in Metabolism and Inflammation Program at the Centenary Institute and collaborating author on the research paper.
“Some tumours, such as breast cancer, grow because the BRCA2 protein inside a cell in our body is defective, thus causing insufficient DNA repair.”
“We were able to find proof that BRCA2 is regulated by the DPP9 enzyme. When we removed DPP9 from cells, DNA repair slowed down. This study supports our previous research that a DPP9 deficiency can increase the risk of a tumour starting.”
The flip side of this new discovery say the researchers’ is that inhibition of DPP9 may also be therapeutically useful for enhancing existing cancer therapies that disrupt DNA repair in tumours. Such cancer therapies include radiation therapy and the drug Olaparib.
“This research is important as it opens up a new field of understanding of a previously unknown fundamental role of DPP9 in cell function and disease,” said Professor Gorrell.
The international study was led by researchers from the University of Freiburg, Germany and the University Medical Center Göttingen, Germany.
Professor Gorrell and his group at the Centenary Institute first discovered the enzyme DPP9 in 1999.