How do cancer cells utilize the enzyme telomerase?

Cancer cells utilize telomerase to enable indefinite cell division, which is crucial for their unchecked proliferation. Telomerase is an enzyme that extends the telomeres, which are repetitive DNA sequences located at the ends of chromosomes. In normal somatic cells, telomeres shorten with each cell division due to the inability of DNA polymerase to completely replicate the ends of linear chromosomes. When telomeres become too short, cells undergo senescence or apoptosis.

However, many cancer cells reactivate telomerase, which allows them to maintain or even lengthen their telomeres. This reactivation is a key factor in the ability of cancer cells to bypass the normal limitations on cell division, enabling them to divide indefinitely and contribute to tumor growth. This characteristic is one of the hallmarks of cancer, allowing tumors to expand and metastasize.

Thus, the ability of cancer cells to switch on telomerase is essential for their survival and proliferation, making them more aggressive and resilient compared to normal cells, which typically do not express this enzyme.