It is well recognised that upregulation/reactivation of telomerase, the telomere-lengthening enzyme, is the sine qua non of cellular immortalisation and malignant transformation. But there is also convincing evidence that telomerase stands at a crossroads where several developmental signalling pathways meet and that its upregulation/reactivation has effects beyond maintaining telomere length, such as altering energy metabolism and modulating gene expression. We believe that it is important to realise that, in a pathological context, such extratelomeric effects of telomerase are related to the emergence and persistence of the cancer stem cell (CSC) phenotype. Given the common conception of cancer stemness as a major contributor to therapy resistance and tumour relapse, a more complete annotation of biological mechanisms for its regulation by telomerase will provide the opportunity to develop telomerase-targeted anticancer therapies which kill or differentiate CSCs effectively.
Part of the book: Telomere