Relocation of NPM Affects the Malignant Phenotypes of Hepatoma SMMC-7721 Cells.

Li X, Xu DH, Liu F et al.

Department of Basic Medicine, Medical College of Xiamen University / Cancer Research Center of Xiamen University, Xiamen 361102, P.R. China.

Journal of cellular biochemistry. Mar 2017.

Nucleophosmin(NPM), heavily implicated in diverse solid tumors, is an important multifunctional protein mainly located in the nucleolus. Our previous study confirmed that NPM can also localize and accumulate in the cytoplasm of liver cancer cells. However, the role of cytoplasmic NPM (NPMc +) is unclear. Here we showed that both nucleolar NPM and NPMc+ could promote cell proliferation, although the effect of NPMc+ was weaker than that of NPM. Cell adhesion ability of hepatoma cells was significantly reduced to a greater extent by NPMc+ expression. nucleolar NPM enhanced cell migration and invasion, whereas NPMc+ impeded cell migration and invasion. The investigation of NPM interactional proteins by proteomic method demonstrated that the NPM was involved in multiple biological processes. By contrast, the interactional proteins of NPMc+ were mainly implicated in tRNA amino acylation regulation. The interactional network of NPMc+ was significantly small and simple. These results suggested that relocation of NPM altered its interactional network and consequently disturbed the primary functions, including cell proliferation, adhesion, migration, and invasion. NPM plays a promotional role in cancer and the reducing relocation may be a potential therapeutic target for hepatocellular carcinoma. This article is protected by copyright. All rights reserved.