Fig. (2) Telomerase inhibition by G-quadruplex inducersidentified in the NCI diversity set I. The ability of compounds identified as G-quadruplex inducers to inhibit human telomerase was tested at 10 µM compound using a direct primer extension assay. Percent inhibition is reported below each lane. Above each lane is the compound tested in the experiment. The lane marked + control is a positive control for telomerase activity in the absence of inhibitor; and the lane marked hTR-AS is acontrol for telomerase inhibition in the presence of a telomerase inhibitorhTR-AS (200nM) that acts as a template agonist. LC (loading and recovery control) is a 115 nucleotide, 5´-³²P-end labeled DNA oligonucleotide. %TI, Percent inhibition of telomerase activity compared to the positive control.