Through immunofluorescence experiment, we found that BR2-p21Ras scFv fusion protein was efficiently internalized into K-ras mutated colon cancer HCT116 cells, N-ras mutated neuroblastoma SK-N-SH cells, and human glioma cell line U251 with wild-type H-p21Ras overexpression. This evidence concerns the gene KRAS and neuroblastoma.