title: Bioluminescent method for detecting telomerase activity.
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.
  
  
  CONCLUSIONS
  ELIPA is a simple and sensitive homogeneous method to quantify telomerase activity.
authors.affiliation: National Laboratory of Biomedical Photonics, Institute of Environmental Medicine, Tongji Medical College of Huazhong University of Science and Technology, 13 Hangkong Rd., Wuhan 430030, The People's Republic of China. shunqing@public.wh.hb.cn
authors.forename: Shun-Qing
authors.initials: SQ
authors.lastname: Xu
authors.forename: Min
authors.initials: M
authors.lastname: He
authors.forename: Hong-Ping
authors.initials: HP
authors.lastname: Yu
authors.forename: Xiao-Yang
authors.initials: XY
authors.lastname: Wang
authors.forename: Xiang-Lin
authors.initials: XL
authors.lastname: Tan
authors.forename: Bin
authors.initials: B
authors.lastname: Lu
authors.forename: Xi
authors.initials: X
authors.lastname: Sun
authors.forename: Yi-Kai
authors.initials: YK
authors.lastname: Zhou
authors.forename: Qun-Feng
authors.initials: QF
authors.lastname: Yao
authors.forename: Yong-Jun
authors.initials: YJ
authors.lastname: Xu
authors.forename: Zhi-Ren
authors.initials: ZR
authors.lastname: Zhang
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry; D014408:Biomarkers, Tumor / Q000032:analysis*; D002384:Catalysis; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008156:Luciferases; D008163:Luminescent Measurements; D008168:Lung / Q000737:chemistry; D008175:Lung Neoplasms / Q000737:chemistry / Q000175:diagnosis; D012091:Repetitive Sequences, Nucleic Acid; D015203:Reproducibility of Results; D019098:Telomerase / Q000032:analysis*; D014407:Tumor Cells, Cultured
chemical_list: D014408:Biomarkers, Tumor; D000255:Adenosine Triphosphate; D008156:Luciferases; D019098:Telomerase