title: Concomitant reduction of matrix metalloproteinase-2 secretion and intracellular reactive oxygen species following anti-sense inhibition of telomerase activity in PC-3 prostate carcinoma cells.
abstract: BACKGROUND
  The level of activity of the telomerase has been shown to correlate with the degree of invasiveness in several tumor types. In addition, cellular redox state is believed to regulate the secretion of matrix metalloproteinase-2 (MMP-2).
  
  
  OBJECTIVE
  To determine the effect of anti-sense telomerase treatment of prostate cancer cells on MMP-2 activity, and the reactive oxygen and nitrogen species (two effectors of cellular redox state).
  
  
  METHODS
  Anti-sense oligonucleotide against RNA component of human telomerase (hTR) was introduced into the cells using Fugene-6 transfection reagent. The activity of telomerase was assessed using Telomere Repeat Amplification Protocol (TRAP assay). Activity of matrix metalloproteinase-2 (MMP-2) was determined by zymography. Levels of intracellular reactive oxygen species (ROS) and nitric oxide metabolites were measured by dichlorofluorescein diacetate (DCFH-DA) staining and Griess reagent, respectively. The level of apoptosis was determined using TUNEL assay.
  
  
  RESULTS
  TRAP assay showed more than 90% inhibition of telomerase activity after 72 h of transfection. Pro-MMP-2 activity was decreased down to 50% of the control levels. Intracellular reactive oxygen species were also significantly decreased. Neither apoptosis rate nor the level of nitric oxide metabolites was significantly different between anti-sense treated and control cells.
  
  
  CONCLUSIONS
  Concomitant reduction of the pro-MMP-2 secretion and ROS in PC-3 cells following hTR inhibition suggests that over-activity of telomerase in cancer cells might increase the level of matrix metalloproteinase-2 and thus, be directly involved in the invasion process through enhancement of intracellular oxidative stress.
authors: Hematology, Oncology and BMTResearch Center, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors: Ahmad
authors: A
authors: Shariftabrizi
authors: Mohammad Reza
authors: MR
authors: Khorramizadeh
authors: Farshid
authors: F
authors: Saadat
authors: Kamran
authors: K
authors: Alimoghadam
authors: Farnaz
authors: F
authors: Safavifar
authors: Mohammad Reza
authors: MR
authors: Ebrahimkhani
mesh_terms: D017209:Apoptosis; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D061965:Matrix Metalloproteinase Inhibitors; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D011471:Prostatic Neoplasms / Q000201:enzymology*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D019098:Telomerase / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D004268:DNA-Binding Proteins; D061965:Matrix Metalloproteinase Inhibitors; D016376:Oligonucleotides, Antisense; D017382:Reactive Oxygen Species; D019098:Telomerase; D020778:Matrix Metalloproteinase 2