Modification of Proliferation and Apoptosis in Breast Cancer Cells by Exposure of Antioxidant Nanoparticles Due to Modulation of the Cellular Redox State Induced by Doxorubicin Exposure.

In this report, we investigated whether the use of chitosan-carrying-glutathione nanoparticles (CH-GSH NPs) can modify proliferation and apoptosis, and reduce cell damage induced by doxorubicin on breast cancer cells. Doxorubicin is a widely used antineoplasic agent for the treatment of various types of cancer. However, it is also a highly toxic drug because it induces oxidative stress. Thus, the use of antioxidant molecules has been considered to reduce the toxicity of doxorubicin. CH-GSH NPs were characterized in size, zeta potential, concentration, and shape. When breast cancer cells were treated with CH-GSH nanoparticles, they were localized in the cellular cytoplasm. Combined doxorubicin exposure with nanoparticles increased intracellular GSH levels. At the same time, decreasing levels of reactive oxygen species and malondialdehyde were observed and modified antioxidant enzyme activity. Levels of the Ki67 protein were evaluated as a marker of cell proliferation and the activity of the Casp-3 protein related to cell apoptosis was measured. Our data suggests that CH-GSH NPs can modify cell proliferation by decreasing Ki67 levels, induce apoptosis by increasing caspase-3 activity, and reduce the oxidative stress induced by doxorubicin in breast cancer cells by modulating molecules associated with the cellular redox state. CH-GSH NPs could be used to reduce the toxic effects of this antineoplastic. Considering these results, CH-GSH NPs represent a novel delivery system offering new opportunities in pharmacy, material science, and biomedicine.