We observed that exogenous expression of maspin cDNA generated from MCF10A showed cytoplasmic localization in MDA-MB-231, whereas its expression showed pan-cellular localization in MCF10A (Fig. 2A–C), suggesting that the nuclear translocation of maspin in breast cancer cells depends on the carrier, but not tag sequence including NLS. Here, SERPINB5 is linked to breast carcinoma.