Normally these vital end caps protect the loose ends of chromosomes from being chewed up or joined together, but are themselves whittled down every time the cell divides. (uchospitals.edu)
Unregulated growth is due in large part to the fact that tumor cells can rebuild protective ends of their chromosomes, which are made of repeated DNA sequences and proteins. (sciencedaily.com)
For example, one such surface on a protein ensures that telomerase can find its way to the physical ends of chromosomes. (salk.edu)