GPT and cancer: Cancer cells circumvent replicative telomere shortening by stabilizing them [6] through one of two mechanisms: reactivation of telomerase, the enzyme that extends telomeres (85–90% of cancers) [7,8,9,10], or homologous recombination between sister chromatids, a phenomenon termed alternative lengthening of telomeres (ALT) (3–10% of cancers) [10,11,12].