There is some indication that when a telomere becomes very short, the cell perceives it as a break in the DNA and the cell dies to protect the proliferation of incorrect genetic information. As well, short telomeres have been linked to such health risks as cancer, dementia, strokes, arthritis, diabetes etc. To escape death, cancerous cells that replicate more often, are able to activate an enzyme called 'telomerase' that can lengthen the telomeres so they can continue to grow.
UT Southwestern Researchers Collaborate On Parkin Enzyme Related To Parkinson’s Disease, New Therapeutic Strategy: http://bionews-tx.com/news/2013/07/26/ut-southwestern-researchers-collaborate-on-parkin-enzyme-related-to-parkinsons-disease-new-therapeutic-strategy/
CPRIT-Funded Study Reveals Genetic Diversity Within Tumors Predicts Outcome in Head and Neck Cancer: http://bionews-tx.com/news/2013/05/22/cprit-funded-study-reveals-genetic-diversity-within-tumors-predicts-outcome-in-head-and-neck-cancer/