Co-delivery with nano-quercetin enhances doxorubicin-mediated cytotoxicity against MCF-7 cells.

Quercetin, the plant-derived phenolic compounds, plays a pivotal role in controlling hemostasis, by having potent antioxidant and free-radical scavenging properties. This flavonoid in combination with chemotherapeutic drugs improves the efficacy of these agents in induction of apoptosis in cancer cells. This study investigated the role of nano-quercetin (phytosome) in doxorubicin-induced apoptosis. Nanoparticles were characterized for particle size, zeta potential, scanning electron microscopy (SEM) and differential scanning calorimetric assessments. Anti-proliferative effect of formulations was evaluated by MTT assay. mRNA expression levels of target genes were measured by real time RT-PCR. The mean size of nanoparticles was 85 ± 2 nm with nearly narrow size distribution which was confirmed by SEM analysis. Our results showed that co-treatment of MCF-7 breast cancer cells with nano-quercetin and doxorubicin increased the percentage of apoptosis from 40.11 ± 7.72-58 ± 7.13 (p < 0.05). Furthermore, mRNA expression levels for downstream genes including NQO1 and MRP1 showed a marked decrease (p < 0.05). Taken together, our results suggest that phytosome technology can elevate the efficacy of chemotherapeutics by increasing the permeability of tumor cells to chemical agents. Our findings introduce a novel phytosome-dependent strategy to improve delivery of doxorubicin to the breast cancerous tissues.