Synergistic antiproliferative effects of methotrexate-loaded smart silica nanocomposites in MDA-MB-231 breast cancer cells.

In this study, the ability of methotrexate (MTX)-loaded stimuli-responsive novel silica nanocomposites (MSNs) (with mean diameter of ± 60 nm) in the induction of apoptosis, and change in the Bax/Bcl-2 mRNA levels, were investigated. MTT assay and RT -PCR analysis were performed on MDA-MB-231 breast cancer cells, to evaluate their anti-proliferative, apoptotic and anti-apoptotic effects. MTX-loaded MSNs caused marked decrease in the percentage of viable cells, with a significant down-regulation in the level of expression of the anti-apoptotic gene (Bcl-2), and up-regulation in the apoptotic gene (Bax). MTX-loaded MSNs increased the efficacy of the chemotherapeutic agents in the inhibition of cell proliferation and induction of apoptosis.