Inhibition of growth of human tumor cell lines in nude mice by an antisense of oligonucleotide inhibitor of protein kinase C-alpha expression.
A 20-mer phosphorothioate oligodeoxynucleotide (ISIS 3521) designed to hybridize sequences in the 3'-untranslated region of human protein kinase C-alpha (PKC-alpha) mRNA has been shown to inhibit the expression of PKC-alpha in multiple human cell lines. In human bladder carcinoma (T-24) cells, inhibition of PKC-alpha was both concentration dependent and oligonucleotide sequence specific. ISIS 3521 had a IC50 of 50-100 nM for PKC-alpha mRNA reduction and was without effect on the expression of other members of the PKC family of genes (PKC-eta and zeta). Toxicity studies in mice revealed that the oligodeoxynucleotide was well tolerated at repeat doses of 100 mg/kg i.v. for up to 14 days, with no acute toxicity apparent. The oligodeoxynucleotide was found to also inhibit the growth of three different human tumor cell lines, the T-24 bladder, human lung carcinoma (A549), and Colo 205 colon carcinoma grown in nude mice. The inhibition was dose dependent with ID50 values for the growth inhibition between 0.06 and 0.6 mg/kg daily when given i.v., depending on the cell line examined. Three control phosphorothioate oligodeoxynucleotides not targeting human PKC-alpha were without effect on the growth of the tumors at doses as high as 6 mg/kg. Recovery of ISIS 3521 from tumor tissue and resolution by capillary gel electrophoresis revealed that 24 It after the final dose of oligodeoxynucleotide, intact, full-length 20-mer material was present as well as some apparent exonuclease degradation products (e.g., n-1 and n-2 mers). These studies demonstrate the in vivo antitumor effects of an antisense oligodeoxynucleotide targeting PKC-alpha and suggest that this compound may be of value as a chemotherapeutic agent in the treatment of human cancers.
Dean
N
N
Department of Molecular Pharmacology, ISIS Pharmaceuticals, Carlsbad, California 92008, USA.
McKay
R
R
Miraglia
L
L
Howard
R
R
Cooper
S
S
Giddings
J
J
Nicklin
P
P
Meister
L
L
Ziel
R
R
Geiger
T
T
Muller
M
M
Fabbro
D
D
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000633:toxicity; D001483:Base Sequence; D002455:Cell Division / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008969:Molecular Sequence Data; D009368:Neoplasm Transplantation; D009369:Neoplasms / Q000188:drug therapy* / Q000201:enzymology* / Q000473:pathology; D020319:Oligodeoxyribonucleotides, Antisense; D016376:Oligonucleotides, Antisense / Q000494:pharmacology* / Q000633:toxicity; D011493:Protein Kinase C / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D051571:Protein Kinase C-alpha; D013873:Thionucleotides / Q000494:pharmacology* / Q000633:toxicity; D014183:Transplantation, Heterologous; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D007527:Isoenzymes; D020319:Oligodeoxyribonucleotides, Antisense; D016376:Oligonucleotides, Antisense; D013873:Thionucleotides; C108494:ISIS 3521; C496628:PRKCA protein, human; C496630:Prkca protein, mouse; D011493:Protein Kinase C; D051571:Protein Kinase C-alpha