Binding affinity of Cu(II)–VP-16 (etoposide) complex and its analogues to DNA and hydroxyl radical generation During DNA strand breaks Original Research Article

Conformational effects and affinities of VP-16 (etoposide) and its derivatives to DNA in the presence of Cu(II) ion were examined by circular dichroic (CD) spectra. The Cu(II)/Cu(I) redox kinetics and the hydroxyl radical (·OH) generation from the Cu(II)-complexes were estimated by the stopped-flow kinetics. Based on the results, DNA-cleaving activity of Cu(II)-complexes of VP-16 has been shown to be related with binding affinity of the complex to DNA, Cu(II)/Cu(I) redox and ·OH generation, emphasising the mechanism of generated ·OH attack to DNA.