title: Abnormal cytoplasmic dyslocalisation and/or reduction of nucleophosmin protein level rarely occurs in myelodysplastic syndromes.
abstract: The Nucleophosmin1 (NPM1) gene located in chromosome 5q35 is affected by chromosomal translocation, mutation and deletion in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). NPM1 haploinsufficiency reportedly causes MDS-like disorders in knockout mice. Here, we studied mRNA and protein expression in bone marrow (BM) samples from 36 patients with MDS. The NPM1 expression levels of mRNA and protein were not related to chromosome 5 abnormalities and were almost the same as those in normal BM and AML cells. However, the protein levels in AML cells with NPM1 mutations were slightly lower than in those without mutation. Immunochemical studies showed no difference in the staining intensity and subcellular localisation between MDS and normal BM cells. It was concluded that abnormal cytoplasmic localisation and/or significant reduction of NPM1 protein level rarely occurs in MDS. The increase in the number of nuclear NPM1-positive cells may be related to the progression of MDS.
authors.affiliation: Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, and Department of Infectious Diseases, Nagoya University Hospital, Showa-ku, Nagoya, Japan. yishikaw@med.nagoya-u.ac.jp
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Jinglan
authors.initials: J
authors.lastname: Xu
authors.forename: Gyosuke
authors.initials: G
authors.lastname: Sakashita
authors.forename: Takeshi
authors.initials: T
authors.lastname: Urano
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Suzuki
authors.forename: Akihiro
authors.initials: A
authors.lastname: Tomita
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kiyoi
authors.forename: Shigeo
authors.initials: S
authors.lastname: Nakamura
authors.forename: Tomoki
authors.initials: T
authors.lastname: Naoe
mesh_terms: D001853:Bone Marrow / Q000737:chemistry* / Q000473:pathology; D002869:Chromosome Aberrations; D003593:Cytoplasm / Q000737:chemistry*; D018450:Disease Progression; D006801:Humans; D009154:Mutation; D009190:Myelodysplastic Syndromes / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D009687:Nuclear Proteins / Q000032:analysis* / Q000235:genetics*; D000090243:Nucleophosmin; D012333:RNA, Messenger / Q000032:analysis
chemical_list: C000716967:NPM1 protein, human; C000715570:Npm1 protein, mouse; D009687:Nuclear Proteins; D012333:RNA, Messenger; D000090243:Nucleophosmin