Nucleophosmin is a nucleolar phosphoprotein involved in cell proliferation, cytoplasmic/nuclear shuttle transportation, nucleic acid binding, ribonucleic cleavage, centrosome duplication, and molecular chaperoning. Its activity is dependent on oligomerization at its N-terminal domain, and it is abundantly expressed in tumor and developing cells where it serves to inhibit both cellular differentiation and apoptosis.NSC 348884 is a small molecule that inhibits the formation of nucleophosmin dimers by disrupting a required binding pocket. It can inhibit cell proliferation and induce apoptosis in various cancer cell lines with IC50 values ranging from 1.4-4 µM.