Impact of oxidative stress on telomere biology.

Telomere integrity is essential for genome stability and it regulates cell proliferation and tissue renewal. Several lines of evidence indicate that telomeres are particularly sensitive to oxidative damage. Moreover, recent studies demonstrate striking inhibitory effects of oxidative damage on telomerase activity. On the other hand, several mechanisms have been uncovered that either counteract oxidative damage at telomeres or remove the modified lesions. Here, we review the current understanding of oxidative damage and protection of telomeric DNA. We discuss how oxidative telomeric lesions impact on telomerase, the regenerative capacity of stem cells and cancer. Finally, we propose how through a better understanding of the involved pathways it may become possible to target telomerase in cancer cells in future cancer therapies.