Evaluation of Metastasis Suppressor Genes Expression and In Vitro Anti-CancerEffects of Zinc Oxide Nanoparticles in Human Breast Cancer Cell Lines MCF-7 and T47D

Background: Metallic nanoparticles are useful materials to be applied in biomedicalresearch. In this study, the possible apoptotic and anti-metastatic activity of Zinc OxideNanoparticles (ZnONPs) was assessed in breast cancer cells.Methods: First, in vitro cell viability was investigated by MTT assay in two humanbreast cancer cells (MCF-7 and T47D) and normal Human Embryonic Kidney (HEK293)cells at 37°C overnight. Apoptosis induced by ZnONPs was evaluated by annexin V/PIstaining, cell cycle analysis and caspase assay in cancerous cells. Moreover, quantitativereal-time PCR was employed for the detection of two metastasis suppressor genes(KAI-1 and NM23) expression in cancerous cells.Results: Data demonstrated that ZnONPs exert a dose-dependent inhibitory effect onthe viability of T47D and MCF-7 cells, while no cytotoxic effect was observed on normalHEK293 cells. The mRNA expression levels of KAI-1 and non-metastatic protein(NM23) genes were up-regulated in ZnONP-exposed cancerous cells. ZnONPs werealso found to enhance the apoptosis properties of cells by annexin V/PI staining, andcaspase assay in cancerous cells. Furthermore, ZnONPs can increase sub-G1 populationas compared to negative control.Conclusion: Our findings showed that ZnONPs induce apoptotic activity and canmodulate metastasis by up-regulating of KAI-1 and NM23 gene expression in twobreast cancer (MCF-7 and T47D) cells.