Hammerhead ribozyme-mediated cleavage of the human insulin-like growth factor-II ribonucleic acid in vitro and in prostate cancer cells.
Insulin-like growth factor (IGF)-II plays an important role in fetal growth and development. IGFs are potent mitogens for a variety of cancer cells. A paracrine/autocrine role of IGF-II in the growth of breast and prostate cancer cells has been suggested. To test the role of IGF-II in cancer cell growth, hammerhead ribozymes targeted to human IGF-II RNA were constructed. Single (R)- and double (RR)-ribozymes were catalytically active in vitro whereas mutant ribozymes (M or MM) did not cleave IGF-II RNA. RR was more active than R. In human prostate cancer PC-3 cells, both R and RR similarly suppressed IGF-II messenger RNA (mRNA) levels (approximately 40%) compared with the level in parental or M-expressing PC-3 cells. Polymerase II and III promoter-driven R similarly suppressed IGF-II mRNA levels. Suppression of IGF-II mRNA levels by R was associated with suppression of IGF-II protein levels. R- (or RR-) expressing PC-3 cells did not grow under serum-starved conditions and showed prolonged doubling times in the presence of 10% FCS compared with those of parental or M-expressing cells. These results substantiated that IGF-II plays a critical role in prostate cancer cell growth.
Xu
Z D
ZD
Department of Molecular Biology, City of Hope Medical Center, Duarte, California 91010, USA.
Oey
L
L
Mohan
S
S
Kawachi
M H
MH
Lee
N S
NS
Rossi
J J
JJ
Fujita-Yamaguchi
Y
Y
D001483:Base Sequence; D002384:Catalysis; D002455:Cell Division; D015870:Gene Expression; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D007700:Kinetics; D008297:Male; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011401:Promoter Regions, Genetic; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D012313:RNA / Q000378:metabolism*; D012320:RNA Polymerase III / Q000235:genetics; D016337:RNA, Catalytic / Q000737:chemistry* / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
D016337:RNA, Catalytic; D012333:RNA, Messenger; D012313:RNA; D007335:Insulin-Like Growth Factor II; D012320:RNA Polymerase III