Ascorbate-Cu2+ fragments melanoma DNA but not fibroblast DNA into a discrete DNA population.
Ascorbate-Cu2+ shows considerable cytotoxicity for human melanoma cells at a dose which has very little effect on human fibroblasts. Ascorbate itself inhibits DNA synthesis in melanoma cells but does not fragment the parental DNA. However, the combined action of ascorbate-Cu2+ generates fragmentation of the parental DNA due to the induction of alkali-labile bonds in the DNA. In contrast, if DNA polymerase alpha is inhibited by aphidicolin prior to treatment with ascorbate-Cu2+ one cannot detect the fragmentation of the DNA. The generated fragments show a discrete appearance in agarose gel electrophoresis with a single-stranded size of approximately 5 kb. When fibroblasts were analyzed using the same experimental protocol it was not possible to detect the fragmentation of the DNA.
D016590:Aphidicolin; D001205:Ascorbic Acid / Q000494:pharmacology*; D002478:Cells, Cultured; D003300:Copper / Q000494:pharmacology*; D004257:DNA Polymerase II / Q000037:antagonists & inhibitors; D004261:DNA Replication / Q000187:drug effects; D004273:DNA, Neoplasm; D004224:Diterpenes / Q000494:pharmacology; D004587:Electrophoresis, Agar Gel; D005347:Fibroblasts / Q000187:drug effects; D006801:Humans; D008545:Melanoma / Q000235:genetics*
D004273:DNA, Neoplasm; D004224:Diterpenes; D016590:Aphidicolin; D003300:Copper; D004257:DNA Polymerase II; D001205:Ascorbic Acid