Use of PCR-array to profile expressed genes in human keratinocyte hacat cells after exposure to Quantum Dots

Quantum dots (QDs) nanoparticles have potential applications in biomedical research, as imaging and diagnostic agents, because of their fluorescent property. Despite the widespread use of nanoparticles, there are many unknowns in understanding on their nanotoxicities and mechanisms. This study evaluated the effects of Quantum Dots (QDs) on gene expression profiles of human keratinocyte HaCaT cells. Total RNA was prepared from the exposure groups to QDs with diverse physicochemical properties (565-PEG-amine, 565-carboxylic acid, 655-carboxylic acid) in various concentrations, and real-time RT-PCR analysis was performed using human oxidative stress and antioxidant defense array. Our study indicated that antioxidant defense and oxidative stress category, such as nitric oxide synthase 2A (NOS2A), dual specificity phosphatase 1 (DUSP1), dual oxidase (DUOX), 24-dehydrocholesterol reductase (DHCR24), peroxidase in homolog (Drosophila)-like (PXDNL), scavenger receptor class A (SCARA3) and thyroid peroxidase (TPO), were represented by all three QDs exposure groups. Therefore, the up-regulation of these enzymes by QDs could increase the production of reactive oxygen species (ROS). The results of our study showed that QDs contained a potential to produce ROS via metabolic pathways, inducing oxidative stress. The results supported that the mechanism of nanotoxicity could be correlated with active oxygen production, oxidative stress, apoptosis, and antioxidant defense mechanisms.