Cancer cells achieve immortality by employing either homology-directed repair (HDR) or the telomerase enzyme to maintain telomeres. ALT (alternative lengthening of telomeres) refers to the subset of cancer cells that employ HDR. Many ALT features are conserved from yeast to human cells, with the yeast equivalent being referred to as survivors.
View Article and Find Full Text PDFCancer cells activate telomere maintenance mechanisms (TMMs) to bypass replicative senescence and achieve immortality by either upregulating telomerase or promoting homology-directed repair (HDR) at chromosome ends to maintain telomere length, the latter being referred to as ALT (Alternative Lengthening of Telomeres). In yeast telomerase mutants, the HDR-based repair of telomeres leads to the generation of 'survivors' that escape senescence and divide indefinitely. So far, yeast has proven to provide an accurate model to study the generation and maintenance of telomeres via HDR.
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