Letters: July 2023

Cost of immortality

Philip Ball’s article on the idea that rejuvenating the ends of chromosomes can be an anti-aging elixir of youth injects healthy scepticism into what appear to be some outrageous claims.

The restoration of activity for the telomerase enzyme will, it is suggested, elongate those telomeric chromosome ends and lead to prolonged life for our cells. But this approach may be naïve and even positively harmful. The article suggests, quite rightly, that this is a consequence of a lack of appreciation of the complex biology involved in aging and telomere maintenance. However, there is another, yet more concerning reason. Telomerase expression can indeed confer immortality on cells but this comes with a heavy price. The enzyme is up-regulated in over 90% of human cancers and induction of telomerase activity is a major contributor to tumorigenesis – indeed this is one of the key hallmarks of cancer. Unsurprisingly there have been several attempts to develop telomerase inhibitors as anti-cancer agents, at least one of which has reached clinical trials.