Migration inhibition and selective cytotoxicity of cobalt hydroxide nanosheets on different cancer cell lines

Abstract

Invasion and migration are major characteristics of malignant cancers. Inhibiting the migration of cancer cells, rather than simply removing the primary tumor, is essential for improving the survival rates. Two-dimensional (2D) materials have important application prospects in the field of biomedicine (especially in cancer therapy) due to their unique physicochemical properties. However, the basic biological effects of 2D material cobalt-based layered double hydroxides, especially its cytotoxicity and migration effects on a variety of cells, have not yet been revealed. Herein, the effect of 5 nm thick β-Co(OH)₂ nanosheets (NSs) on cell viability and migration of normal cells and various cancer cells and their possible mechanisms were investigated. The cell viability assay and migration ability analysis found that β-Co(OH)₂ NSs had a concentration-dependent and selective biological effects on normal cells HUVEC and cancer cells (4T1, SMMC-7721, and B16 cells). Compared with normal cells HUVEC, β-Co(OH)₂ NSs showed remarkably stronger and differentiated cytotoxicity to cancer cells (4T1, SMMC-7721, and B16 cells), and it was found by wound healing and transwell assays that β-Co(OH)₂ NSs also can inhibit cancer cell migration more sensitively which may be attributed to the down-regulation of the key epithelial-mesenchymal transition protein Snail2. This study on revealing the basic biological effects of cobalt-based nanosheets will not only promote the understanding of the interaction between nanosheets and cells, but will also help in developing cancer treatment platforms based on cobalt-based nanosheets to promote their applications in the inhibition of tumor migration and metastasis.