The effect of carboxylated nanodiamond (cNDs) on the migration of HepG2 cells

Nanodiamonds (NDs) could be regarded as one of the most attractive nanocarbon materials available so far for biomedical applications. After being carboxylated, they can be used as the carrier for drug-delivery systems and cell probes. However, their effect on cell migration and the related mechanism remains unknown. Herein, we have evaluated the effect of carboxylated nanodiamonds (cNDs) on the migration of HepG2 cells (a human hepatocellular carcinoma cell line). The effect on cellular migration was assessed by transwell assay and wound assay after 24 h exposure of the cells to different concentrations of cNDs. In this study, we found that a high concentration of cNDs (>= 100 mu gml(-1)) could inhibit HepG2 cell migration. The real-time PCR (polymerase chain reaction) results also showed that the mRNA level of the gene-related cell migration (such as: beta-catenin, MMP2, vimentin, and integrin beta 1) changed after 24 h exposure of the cells to cNDs. These results suggest that NDs should no longer be viewed only as simple carriers and probes for biomedical applications, but that they can also play an active role in regulating cell behaviors. Furthermore, understanding the mechanism of mediating the biological effects might help the design of drug-delivery systems and cell probes based on cNDs. (C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim