2-5A antisense therapy directed against human telomerase RNA inhibits telomerase activity and induces apoptosis without telomere impairment in cervical cancer cells.
Human telomerase RNA (hTR), an important component of telomerase, is a possible target of telomerase-based cancer gene therapy. The present study was undertaken to assess the efficacy of antisense hTR therapy using newly developed 2-5A (5'-phosphorylated 2'-5'-linked oligoadenylate)-linked oligonucleotides against cervical cancer cells. ME180 and SiHa cells were treated with 2-5A-linked antisense hTR designed to complement the region of hTR between residues 76 and 94. The hTR expression, telomerase activity, cell viability, and apoptosis were then examined. The 2-5A anti-hTR effectively degraded hTR and inhibited telomerase activity. The 2-5A mutant anti-hTR and the anti-hTR without 2-5A were not capable of inhibiting telomerase activity. Inhibition of telomerase by 2-5A anti-hTR rapidly decreased cell viability only in telomerase-positive cells within 3-6 days after the treatment, when telomere length has not yet been shortened. This inhibition was associated with apoptosis, possibly through activation of caspase family members. These findings suggest that 2-5A-linked antisense-hTR therapy has a potent telomerase-inhibitory effect associated with a cytocidal effect from caspase-induced apoptosis, and may therefore be a potential tool in telomerase-based gene therapy against cervical cancers.
Yatabe
Noriyuki
N
Department of Obstetrics and Gynecology, Kanazawa University, School of Medicine, 13-1, Takaramachi, Kanazawa, Ishikawa 920-8641, Japan.
Kyo
Satoru
S
Kondo
Seiji
S
Kanaya
Taro
T
Wang
Zhuo
Z
Maida
Yoshiko
Y
Takakura
Masahiro
M
Nakamura
Mitsuhiro
M
Tanaka
Masaaki
M
Inoue
Masaki
M
D017209:Apoptosis; D015139:Blotting, Southern; D002470:Cell Survival; D005260:Female; D005434:Flow Cytometry; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D009841:Oligonucleotides / Q000494:pharmacology; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D012313:RNA / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019098:Telomerase / Q000037:antagonists & inhibitors* / Q000235:genetics*; D016615:Telomere / Q000378:metabolism; D013997:Time Factors; D014162:Transfection; D014407:Tumor Cells, Cultured; D002583:Uterine Cervical Neoplasms / Q000235:genetics* / Q000628:therapy
D009841:Oligonucleotides; D016376:Oligonucleotides, Antisense; D012313:RNA; D019098:Telomerase