James C. Norton

Comparison of the telomeric repeat amplification protocol (TRAP) to the new TRAP-eze telomerase detection kit

The ribonucleoprotein, telomerase, is believed to be responsible for the maintenance of telomere length in immortal and cancer cells. A PCR-based assay for the detection of telomerase activity (TRAP assay: telomeric repeat amplification protocol) was developed, allowing fast and efficient detection of telomerase activity when sample amounts are limiting. Of the thousands of primary human tumors examined using the TRAP assay, almost 90% have been shown to exhibit telomerase activity. Thus, for the early detection of cancer and for the rapid screening of compounds and drugs in cancer therapeutics, methods for the detection of telomerase activity are rapidly emerging. The recently developed TRAP-ezeTM kit from Oncor, Inc. gives increased sensitivity with decrease sample processing time, allowing improved detection of telomerase activity in a large number of samples. In the present study, we have addressed some of the technical aspects and limitations of critical importance for reproducibility, reliability, and linearity of the standard TRAP assay and the TRAP-ezeTM kit using cell culture and clinical materials.

Specific and nonspecific inhibition of transcription by DNA, PNA, and phosphorothioate promoter analog duplexes

Abstract DNA duplexes analogous to the promoters for SP6 or T7 RNA polymerase inhibit transcription with exquisite selectivity. By contrast, phosphorothioate oligomers inhibit nonselectively, and peptide nucleic acid (PNA) duplexes and PNA:DNA heteroduplexes do not inhibit at all. The absence of recognition of proteins by PNAs may prove to be a substantial advantage for their use as anti-sense agents and nucleic acid probes.