TiO nanoparticles enhance the chemotherapeutic effects of 5-fluorouracil in human AGS gastric cancer cells via autophagy blockade.

AIMS

Nanoparticles (NPs)-based drugs have been recently introduced to improve the efficacy of current therapeutic strategies for the treatment of cancer; however, the molecular mechanisms by which a NP interacts with cellular systems still need to be delineated. Here, we utilize the autophagic potential of TiO NPs for improving chemotherapeutic effects of 5-fluorouracil (5-FU) in human AGS gastric cells.

MATERIALS AND METHODS

Cell growth and viability were determined by trypan blue exclusion test and MTT assay, respectively. Vesicular organelles formation was evaluated by acridine orange staining of cells. Cell cycle and apoptosis were monitored by flow cytometry. Reactive oxygen species (ROS) level were measured by DCHF-DA staining. Autophagy was examined by q-PCR and western blotting. Molecular docking was used for studying NP interaction with autophagic proteins.

KEY FINDINGS

TiO NPs increase ROS production, impair lysosomal function and subsequently block autophagy flux in AGS cells. In addition, the autophagy blockade induced by non-toxic concentrations of TiO NPs (1 μg/ml) can promote cytotoxic and apoptotic effects of 5-FU in AGS cells.

SIGNIFICANCE

These results confirm the beneficial effects of TiO NPs in combination with chemotherapy in in vitro model of gastric cancer, which may pave the way to develop a possible solution to circumvent chemoresistance in cancer.