In conclusion, as the anti-migratory effect of PA63 plus His6-NDPKA on MDA-MB-231 cells was apparently as effective as NME1/NDPK-A overexpression by conventional methods, our data provide proof-of-feasibility that the specific PA63-mediated introduction of a His6-tagged version of the tumor metastasis suppressor protein NME1/NDPK-A into the cytosol of cancer cells can be an attractive novel approach to reduce the migration and metastasis, e.g., of certain breast cancer types. This evidence concerns the gene NME1 and breast cancer.