The immunohistochemical analyses of NPL4 subcellular localization were performed on archival paraffin sections from two complementary cohorts of: i) triple-negative breast cancer (n = 63), and ii) serous ovarian carcinomas (n = 51), with all these 114 human clinical samples showing consistently NPL4 protein localized outside the nucleolus. The gene discussed is NPLOC4; the disease is ovarian serous carcinoma.