Comparative Cytotoxicity Of Nanosilver In Human Liver Hepg2 And Colon Caco2 Cells In Culture
In this clinical study, published in the Journal of Applied Technology in February 2014, the researchers treated human liver HepG2 cells (i.e., liver cancer cells) and human colon Caco2 cells (i.e., colorectal cancer cells) with silver nanoparticles with an average size of 20.4 nm in order to evaluate their toxicity to the cells.
The researchers found significant toxicity to both cancer cell lines, but at different concentrations, with the colorectal cancer cells requiring a concentration of silver nanoparticles 10 times higher than the liver cancer cells. Interestingly, this was not a silver v/s cancer study, per se. The researchers simply used the two different lines of cancer cells to evaluate silver’s toxicity to cells in general. I’ve long argued against this approach, because it appears silver has a special affinity for cancer cells (and would therefore be more toxic to them), and because previous studies have demonstrated silver to be toxic to cancer cells without causing harm (relatively speaking) to surrounding healthy cells. In this case, the researchers actually concluded this to be the case, stating, “The HepG2 and Caco2 cells used this study appear to be targets for silver nanoparticles.
The results of this study suggest that the differences in the mechanisms of toxicity induced by nanosilver may be largely as a consequence of the type of cells used. This differential rather than universal response of different cell types exposed to nanoparticles may play an important role in the mechanism of their toxicity.” In other words, cancer cells appear to be far more sensitive to the cytotoxic effects of silver nanoparticles, with some being even more sensitive to others.
