Enhanced antitumor activity of carbendazim on HeLa cervical cancer cells by aptamer mediated controlled release.

Carbendazim, is a broad-spectrum fungicide and also a promising experimental antitumor drug as reproduction and developmental toxicant, which is currently under phase II preclinical trials. In this study, an approach based on controlled and targeted release with aptamers and mesoporous silica nanoparticles was investigated to improve the antitumor activity of carbendazim. To this end, we synthesized aptamer conjugated silica nanoparticles for testing cytotoxicity properties in vitro with human cervical adenocarcinoma (HeLa) cultured cells. Nucleolin (AS1411) binding aptamers were used to entrap carbendazim molecules inside nanopores of MCM-41 type silica nanoparticles to obtain a stimuli-dependent release system. The effect of carbendazim loaded aptamer silica complex was tested and compared to free carbendazim treatment on HeLa cells, demonstrating 3.3 fold increase of toxicity on targeted cells with our delivery system. In addition, cytotoxicity of the complex was determined to be mostly due to increased apoptosis and to a less extend necrosis related pathways.