The effects of silver nanoparticles and doxorubicin combination on DNA structure and its antiproliferative effect against T47D and MCF7 cell lines.

The structural changes in DNA caused by the combined effects of silver nanoparticles (Ag NPs) and doxorubicin (DOX) was investigated along with their corresponding inhibitory roles in the growth of T47D and MCF7 cells. The UV-visible titration studies showed that DOX + AgNPs could form a novel complex with DNA and this interaction is in the interface between the value induced by electrostatic and intercalative binding. The values of binding constants revealed that DOX + AgNPs interact more strongly with DNA as compared to Ag NPs or DOX alone. Our CD data revealed that although Ag NPs and DOX alone could alter DNA structure, this combination leads to transition of DNA conformation to an ordered and compact molecular form so called psi-type, considering that DNA is relatively thermally stable in the condition used. Thus, we observed that DOX + AgNPs induces conformational change on DNA. The anticancer property of DOX + AgNPs by MTT assay, DAPI stain and flow cytometry analyses demonstrated that this combination can tremendously diminish proliferation of T47D and MCF7 cells compared to DOX or Ag NPs alone. Furthermore, this combination was comparatively non-toxic towards the human endometrial stem cells proliferation. Collectively, these results reveal that DOX + AgNPs could proffer a novel strategy for the development of promising and efficient chemotherapy agents.