The effect of carboxylated nanodiamonds on tumor cells migration

Abstract Nanodiamonds and their modified derivatives attract wide attention in medical application for their excellent therapeutic efficacy as drug delivery platforms and unique optical properties as imaging probes. However, besides the well acknowledged good biocompatibility, little is known about their influence on cell migration. In present work, the effect of carboxylated nanodiamonds (cNDs) on cell migration has been investigated. Two cancer cell lines (HeLa and C6) and two normal cell lines (MDCK and NIH/3T3) have been chosen as test cells. The cellular uptake process of cNDs has been visualized by 3D confocal Raman imaging after exposure to different concentrations of cNDs. cNDs show no apparent influence on cells viability up to a concentration of 200 μg/ml. Whereas, cNDs ≥100 μg/ml can inhibit HeLa cell migration and cNDs ≥25 μg/ml exhibit attenuated effect on C6 cell motility after co-cultured with cNDs for 24 h. Further mRNA studies indicate that cNDs with specific concentration downregulate the expression of vimentin in HeLa and C6 cells, which is responsible for cell contact formation, arrangement and transport of signal molecules in cancer metastasis. These results suggest that cNDs play an active role in regulating cancer cells migration besides act as drug carriers and imaging probes.