Model studies on the interactions of a Cu(II)-quinone complex with surfactant micelles and DNA explore its induction of apoptosis in human MDA-MB-231 breast adenocarcinoma cells

Abstract

The interactions of copper complex (CuQ2) of 1-amino-4-hydroxy-9,10-anthraquinone (QH) with calf thymus DNA, anionic surfactant sodium dodecyl sulfate (SDS), and cationic surfactant cetyltrimethylammonium bromide (CTAB) were investigated in an aqueous solution at physiological pH (7.4). Affinities of such molecule to DNA and surfactant micelles, a model for a biological membrane, are important in determining its biological action. Using different models, various binding parameters were evaluated in both of molecule–DNA interaction and molecule–surfactant interaction. The study showed that hydrophobic interaction plays a major role in the binding of CuQ2 to surfactant micelles. In addition, the hydrophobic interaction has an important role in the distribution of CuQ2 between micelle-water phases. Gibbs free energy for the binding and distribution of CuQ2 between the bulk aqueous medium and surfactant micelles were calculated. In order to correlate the physicochemical properties deciphered from the aforementioned studies with the biological property of the molecule, CuQ2 was treated with MDA-MB-231 breast adenocarcinoma cells where it was found that the molecule affects the viability of the cancer cells. Fluorescent staining of the treated cells with AO/EB and Hoechst indicated that the CuQ2 induces apoptosis, suggesting its use in the treatment of breast cancer.