A Label-Free, One-Step Isothermal Assay for Sensitive Detection of Telomerase Activity Using Light-Up Aptamer

Telomerase is a critical biomarker for cancer diagnosis and therapy due to its overexpression in tumor cells. Traditional methods for detecting telomerase activity, such as the telomeric repeat amplification protocol (TRAP), have limitations, including precise temperature control requirements and a risk of false positives. We present the Light-up Aptamer-based Telomerase Assay (LATA), a label-free, one-pot, and one-step method that links telomerase activity to a fluorescent signal via light-up aptamers produced through the reactions of the Klenow fragment and T7 RNA polymerase. LATA exhibited high sensitivity, detecting telomerase activity in HeLa cell extracts down to 0.8 cells (20 cells per mL) within 90 min. Additionally, it effectively differentiated telomerase activity in various cell lines and identified telomerase inhibitors. This method shows great promise for advancing cancer diagnostics and treatment research by overcoming the limitations of current techniques, offering a simple, sensitive, and reliable alternative for telomerase activity detection.