Sensitive and reliable analysis of telomerase activity is important for clinical diagnosis, therapy, and prognosis of osteosarcoma. Telomerase activity is a complicated concept including both the amount of active telomerases and the length of the telomerases extension product. Still, few of the strategies formerly proposed distinguish the two aspects of telomerase activity. Herein, we propose a novel CRISPR-Cas12a-based fluorescent sensing platform that can output signals of both the amounts of telomerase and length of telomerase extension products with the assistance of an elegantly designed stem-loop probe and CRISPR-Cas12a system. On this basis, we induced a novel index, average telomerase activity, for accurate cancer reporting. Through systematic laboratory and clinical experiments, we have demonstrated that average telomerase activity can accurately distinguish cancer cells and has the potential for osteosarcoma staging.
Keywords: CRISPR-Cas12a; TS primer; average telomerase activity; osteosarcoma; stem-loop probe.