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PubMed · 12089169

Bioluminescent method for detecting telomerase activity.

Shun-Qing Xu·Min He·Hong-Ping Yu·Xiao-Yang Wang·Xiang-Lin Tan·Bin Lu·Xi Sun·Yi-Kai Zhou·Qun-Feng Yao·Yong-Jun Xu·Zhi-Ren Zhang
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Abstract

BACKGROUND: Telomerase is a promising biomarker in cancer diagnosis and therapy. The elongation of telomeric repeats catalyzed by telomerase is accompanied by release of six PP(i) for each TTAGGG repeat (1 pmol PP(i)/310 pg telomeric repeats). We developed a novel method to measure telomerase activity by use of an enzymatic luminometric PP(i) assay (ELIPA). METHODS: Extracts of cell lines and tissues were incubated with primer at 30 degrees C for 30 min. Released PP(i) was converted to ATP by sulfurylase, and ATP was detected by a luciferase bioluminescence system. The ELIPA results were compared with results obtained with the conventional telomeric repeat amplification (TRAP)-ELISA in 42 lung carcinoma tissues and 27 control tissues without malignancy. RESULTS: The lower detection limits of ELIPA and TRAP-ELISA were 5 and 10 cells, respectively. The within-run imprecision (CV) of ELIPA was < or =12%. When compared with TRAP-ELISA, the correlation coefficient (r) was 0.79. When we used the cutoff value from ROC analysis to distinguish malignant and nonmalignant tissues, the sensitivity and specificity of ELIPA were 83% and 96%, respectively, whereas the sensitivity and specificity of TRAP-ELISA were 71% and 96%, respectively. CONCLUSION: ELIPA is a simple and sensitive homogeneous method to quantify telomerase activity.

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Adenosine TriphosphateBiomarkers, TumorCatalysisEnzyme-Linked Immunosorbent AssayHumansLuciferasesLuminescent MeasurementsLungLung NeoplasmsRepetitive Sequences, Nucleic AcidReproducibility of ResultsTelomeraseTumor Cells, CulturedJournal ArticleResearch Support, Non-U.S. Gov't

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Shun-Qing Xu, Min He, Hong-Ping Yu, Xiao-Yang Wang, Xiang-Lin Tan, Bin Lu, Xi Sun, Yi-Kai Zhou, Qun-Feng Yao, Yong-Jun Xu, Zhi-Ren Zhang. 2002. Bioluminescent method for detecting telomerase activity.. https://pubmed.ncbi.nlm.nih.gov/12089169/

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