Novel insights into possible ZnO nanoparticle-induced changes in key metabolic enzymes in HeLa cervical cancer cell line

Abstract

Nanoparticles, especially zinc oxide (ZnO) nanoparticles with specific toxicity to cancer cells, have attracted much attention in cancer therapy. The nicotinamide phosphoribosyltransferase (NAMPT) and sirtuins (1, 2, and 7) as key metabolic enzymes are overexpressed in cervical cancer. This study investigates the effect of ZnO nanoparticles on the expression of NAMPT and sirtuin 1, 2, and 7 genes in the cervical cancer cell line (HeLa). ZnO nanoparticles were purchased and then examined for size, shape, and morphology by dynamic light scattering (DLS), scanning electron microscopy (SEM), and UV-spectroscopy. The potential cytotoxicity of ZnO nanoparticles was investigated using the MTT assay, and the expression of NAMPT, SIRT1, SIRT2, and SIRT7 genes was analyzed using the qRT-PCR technique. ZnO nanoparticles with a size of about 60 nm had spherical morphology and a smooth surface and showed a sharp absorption band at 367 nm. Treatment with ZnO nanoparticles exhibited dose-dependent toxicity on HeLa cells. ZnO nanoparticles did not show a significant effect on NAMPT gene expression. A significant increase in the expression of SIRT1 and SIRT7 genes was observed in the treated groups compared to the untreated group. In contrast, SIRT2 gene expression showed a significant decrease in treated groups compared to the untreated group. Treatment with ZnO nanoparticles led to changes in the gene expression of sirtuins (1, 2, and 7), thus possibly influencing the propagation of cervical cancer. However, more extensive research is needed to investigate the relationship between these findings and reveal the underlying mechanisms.