The cytotoxic effects of the AgNPs on PCS-800-011 primary peripheral blood mononuclear cells and 32D-FLT3-ITD leukemia cells were evaluated over 48 h using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The gene discussed is FLT3; the disease is leukemia.