title: Differential antiproliferative actions of 2',5' oligo A trimer core and its cordycepin analogue on human tumor cells.
abstract: The antiproliferative effect of 2',5' A3 core and 2',5'-3'dA3 (cordycepin trimer) core was measured in 8 human tumor cell lines. Cells were treated in a dose-response manner for 72 hr and the concentration of drug necessary to inhibit cell growth 50% (GI50) was determined. A wide range of sensitivities to these drugs was found, even among tumors of the same histological type. The cell lines showed different sensitivities and dose-response curves to the 2',5'A3 and 2',5'-3'dA3 cores. Uptake studies of the 2',5'A3 and 2',5'-3'dA3 cores, using high-pressure liquid chromatography, demonstrated that both cores were rapidly degraded in the tissue culture medium and taken up as adenosine or cordycepin, respectively. There was a direct correlation between the uptake of cordycepin and the antiproliferative effect. In contrast, there was no correlation between cell sensitivity and the uptake of the 2',5'A3 core degradation products. Analysis of intracellular nucleosides and nucleotides indicated that differences in intracellular metabolism of adenosine might explain the different sensitivities of the various cell lines to 2',5'A3 core. Molar equivalent concentrations of adenosine and cordycepin inhibited cell growth; however, equimolar concentrations of these nucleosides were not effective. In addition, the antiproliferative effect of both core compounds and their corresponding nucleosides could be potentiated by the addition of the adenosine deaminase inhibitor, deoxycoformycin. The results indicate that these cores act as prodrugs and that the active metabolites are their corresponding nucleosides.
mesh_terms: D000227:Adenine Nucleotides / Q000494:pharmacology*; D000241:Adenosine / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003070:Coformycin / Q000031:analogs & derivatives / Q000494:pharmacology; D046508:Culture Techniques; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D006801:Humans; D009369:Neoplasms / Q000473:pathology*; D009838:Oligodeoxyribonucleotides / Q000494:pharmacology*; D009841:Oligonucleotides / Q000494:pharmacology*; D009843:Oligoribonucleotides / Q000494:pharmacology*; D015649:Pentostatin
chemical_list: C032558:2',5'-oligoadenylate cordycepin analog; D000227:Adenine Nucleotides; D009838:Oligodeoxyribonucleotides; D009841:Oligonucleotides; D009843:Oligoribonucleotides; D003070:Coformycin; D015649:Pentostatin; C023505:2',5'-oligoadenylate; D000241:Adenosine