Electrochemical detection of genetic damage caused by the interaction of novel bifunctional anthraquinone-temozolomide antitumor hybrids with DNA modified electrode

Abstract

In this work, novel potential anthraquinone-temozolomide (TMZ) antitumor hybrids N-(2-((9,10-dioxo-9,10-dihydroanthracen-1-yl)amino)ethyl)-3-methyl-4-oxo-3,4-dihydroimidazo [5, 1-d][1,2,3,5]tetrazine-8-carboxamide (C-1) and 2-(9,10-dioxo-9,10-dihydroanthracen-1-yl)amino) ethyl-3-methyl-4-oxo-3,4-dihydroimidazo[5,1-d][1,2,3,5]tetrazine-8-carboxylate (C-9) were designed and synthesized successfully. The electrochemical behaviors of C-1 (C-9) involved the reversible processes of 9,10-anthraquinone ring, the irreversible reduction and oxidation processes of TMZ ring. Electrochemical biosensors were constructed with ctDNA, poly (dG) and poly (dA) modifying the surface of glassy carbon electrode (GCE) to evaluate the DNA oxidative damage caused by the interaction of C-1 (C-9) with DNA. Anthracycline skeleton and TMZ ring in C-1 (C-9) could exhibit bifunctional effects with both intercalating and alkylation modes toward DNA strands. The DNA biosensor had good practicability in mouse serum. The results of gel electrophoresis further demonstrated that C-1 (C-9) could effectively intercalated into ctDNA and disrupt plasmid conformation. Finally, anthraquinone-TMZ hybrid C-1 possessed high cytotoxicity toward A549 and GL261 cells, which could be a novel and optimal candidate for the clinic antitumor treatment.

Keywords: Bifunctional antitumor agent; DNA intercalation and alkylation; Electrochemical DNA biosensor.