Synergistic effects of Titanium dioxide nanoparticles and Paclitaxel combination on the DNA structure and their antiproliferative role on MDA-MB-231cells

Objective(s): The objective of this investigation was to evaluate the synergistic effect of paclitaxel (PTX) combined with titanium dioxide nanoparticles (TiO2NPs) on DNA structure and to examine the proliferation of MDA-MB-231cells. Methods: This investigation performed with Ultraviolet spectroscopy, zeta potential investigation, circular dichroism (CD) spectroscopy, ELISA reader and fluorescence spectroscopy. Results: The Ultraviolet results indicated that the structure of DNA in the presence of PTX and TiO2NPs (at a lower concentration) changed significantly rather than TiO2NPs or PTX alone. The fluorescence results exposed that PTX+TiO2NPs could form a complex via non-intercalative mechanism and the PTX+TiO2NPs affinity to DNA increased considerably. The thermodynamics parameters displayed that PTX+TiO2NPs interact with DNA strongly and in this interaction, the hydrophobic force plays an important role. The CD data confirmed that DNA structure was modified by PTX+TiO2NPs via a simple and reasonable mechanism: change in DNA conformation from B to C-form. The negative charge of DNA reduced strongly after addition of PTX+TiO2NPs. The anticancer property of PTX+TiO2NPs by MTT assay demonstrates that this combination can tremendously diminish the proliferation of MDA-MB-231cells compared to PTX or TiO2NPs alone. Conclusions: Based on this investigation TiO2NPs could enhance the affinity and binding of PTX (at a lower concentration) on DNA structure and PTX+NDs can promote mortality of MDA-MB-231 cells. This study can offer an innovative strategy for designing the ideal anti-tumor agents.