Enhancing cancer cell adhesion with clay nanoparticles for countering metastasis.

Cancer metastasis results from the suppression of adhesion between cancer cells and the extracellular matrix, causing their migration from the primary tumor location and the subsequent formation of tumors in distant organs. This study demonstrates the potential use of nano-sized clay mineral particles to modulate adhesions between tumor cells and with the surrounding extracellular matrix. Atomic force microscopy studies of live cell cultures reveal a significant increase in adhesion between tumor cells and their environment after treatment with different types of electrically charged clay nanoparticles. The enhancement of adhesion among cancer cells was further confirmed through scratch type of wound healing assay studies. To provide insight into the adhesion mechanisms introduced by the clay nanoparticles, we performed a molecular-level computer simulation of cell adhesions in the presence and absence of the nanoparticles. Strong van der Waals and electrostatic attractions modelled in the molecular simulations result in an increase in the cohesive energy density of these environments when treated with clay crystallites. The increase in the cohesive energy density after the sorption of clay crystallites on cell-cell and cell-extracellular matrix complexes lends weight to our strategy of using clay nanoparticles for the restoration of adhesion among cancer cells and prevention of metastasis.