Researchers have identified an enzyme that is absent in healthy colon tissue but abundant in colon cancer cells. It appears to drive the conversion of normal tissue into cancer by attaching sugar molecules, or glycans, to proteins in the cell.
The findings appeared in the Journal of Biological Chemistry after a team at the University of Copenhagen studied a group of 20 enzymes that initiate the first step in a distinct kind of glycan modification, called GalNAc-type O-glycosylation, found on diverse proteins.
These enzymes, called GalNAc transferases (GalNAc-Ts), are found in different amounts in different tissues, but their functions are poorly understood.
The team found that one of the GalNAc-Ts, called GalNAc-T6, was absent in healthy colon tissue but present in colon cancer cells. They used CRISPR/Cas engineering of a colon cancer cell line with and without GalNAc-T6 to understand which proteins the enzyme helped attach sugars to, and what effect this had on the cells.
