We investigated the neurotoxic effects of chromium, nickel and cadmium using two different human cell models: induced pluripotent stem cell (iPSC)-derived neurons (iNeurons) carrying a PSP-related mutation in MAPT gene matched with a gene-corrected isogenic control line; and SH-SY5Y neuroblastoma cells (undifferentiated and neuron-like retinoic acid (RA)-differentiated). This evidence concerns the gene MAPT and supranuclear palsy, progressive, 1.