TERT Promoter Eyed With Suspicion and Hope

Abstract

Cancer researchers yearning for a robust universal biomarker of malignancy and tumor grade have long found telomerase a tempting candidate. This enzyme maintains the telomeres at the tips of chromosomes in early development and stem cells but is then usually inactivated, allowing telomeres to erode and limiting cell division. Most cancer cells, however, reactivate telomerase in their quest to become immortal. Current methods to measure telomerase levels for clinical diagnosis and prognosis through DNA, RNA, or protein analysis have technical difficulties, including lack of reliable antibodies and inability to use in paraffin-embedded tissues, said Uri Tabori, M.D., from the Hospital for Sick Children in Toronto, Canada. In the past year, he and others took a different approach, looking at the promoter for the catalytic subunit of telomerase, telomerase reverse transcriptase (TERT) instead of directly at the gene.