This assertion is supported by our demonstration of the cytoplasmic localization of the N181D/N197D, N181A/N197A, and N181Q/N197Q mutants expressed in RK13 epithelial cells and SH-SY5Y neuroblastoma cells and of wild-type PrP and various PrP mutants expressed in tunicamycin-treated cells. This evidence concerns the gene PRNP and neuroblastoma.