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.
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.
Shariftabrizi
Ahmad
A
Hematology, Oncology and BMTResearch Center, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Khorramizadeh
Mohammad Reza
MR
Saadat
Farshid
F
Alimoghadam
Kamran
K
Safavifar
Farnaz
F
Ebrahimkhani
Mohammad Reza
MR
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
D004268:DNA-Binding Proteins; D061965:Matrix Metalloproteinase Inhibitors; D016376:Oligonucleotides, Antisense; D017382:Reactive Oxygen Species; D019098:Telomerase; D020778:Matrix Metalloproteinase 2