title: Knockdown of nucleophosmin induces S-phase arrest in HepG2 cells.
abstract: Nucleophosmin/B23 (NPM) is a universally expressed nucleolar phosphoprotein that participates in proliferation, apoptosis, ribosome assembly, and centrosome duplication; however, the role of NPM in cell cycle regulation is not well characterized. We investigated the mechanism by which NPM is involved in cell cycle regulation. NPM was knocked down using siRNA in HepG2 hepatoblastoma cells. NPM translocation following actinomycin D (ActD) treatment was investigated using immunofluorescent staining. Expression of NPM and other factors involved in cell cycle regulation was examined by Western blotting. Cell cycle distribution was measured using flow cytometry to detect 5-ethynyl-2'-deoxyuridine (EdU) incorporation. Cell proliferation was quantified by the MTT assay. Knockdown of NPM increased the percentage of HepG2 cells in S phase and led to decreased expression of P53 and P21Cip1/WAF1. S-phase arrest in HepG2 cells was significantly enhanced by ActD treatment. Furthermore, knockdown of NPM abrogated ActD-induced G2/M phase cell cycle arrest. Taken together, these data demonstrate that inhibition of NPM has a significant effect on the cell cycle.
authors.affiliation: Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, People's Republic of China.
authors.forename: Qing-Qing
authors.initials: QQ
authors.lastname: Wang
authors.forename: Zhi-Yi
authors.initials: ZY
authors.lastname: Zhang
authors.forename: Jian-Yong
authors.initials: JY
authors.lastname: Xiao
authors.forename: Chun
authors.initials: C
authors.lastname: Yi
authors.forename: Lin-Zi
authors.initials: LZ
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.forename: Jing-Ping
authors.initials: JP
authors.lastname: Yun
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D002453:Cell Cycle; D049109:Cell Proliferation; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D003609:Dactinomycin / Q000494:pharmacology; D055785:Gene Knockdown Techniques; D056945:Hep G2 Cells; D006801:Humans; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D000090243:Nucleophosmin; D034741:RNA, Small Interfering; D016196:S Phase; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: D000903:Antibiotics, Antineoplastic; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; C000716967:NPM1 protein, human; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D000090243:Nucleophosmin; D003609:Dactinomycin
references.citation: J Biol Chem. 2006 Jun 16;281(24):16536-45
references.pmid: 16608843
references.citation: Exp Cell Res. 1983 Jun;146(1):139-49
references.pmid: 6345184
references.citation: J Biol Chem. 1996 Nov 22;271(47):29556-60
references.pmid: 8939883
references.citation: Mol Cell Biol. 2005 Feb;25(4):1258-71
references.pmid: 15684379
references.citation: Br J Cancer. 2007 Feb 12;96(3):477-84
references.pmid: 17245342
references.citation: J Biol Chem. 2009 Jun 12;284(24):16409-16418
references.pmid: 19366707
references.citation: Cell. 2000 Sep 29;103(1):127-40
references.pmid: 11051553
references.citation: J Biol Chem. 1994 Dec 9;269(49):30994-8
references.pmid: 7527039
references.citation: Biochem Pharmacol. 1971 Apr;20(4):771-82
references.pmid: 4998962
references.citation: J Biol Chem. 2005 Mar 25;280(12):10988-96
references.pmid: 15644315
references.citation: Eur J Cell Biol. 1997 May;73(1):58-70
references.pmid: 9174672
references.citation: Zhonghua Bing Li Xue Za Zhi. 2006 Jul;35(7):407-11
references.pmid: 17069676
references.citation: J Biol Chem. 2007 Dec 14;282(50):36744-54
references.pmid: 17951246
references.citation: Cell Cycle. 2009 Sep 1;8(17):2703-7
references.pmid: 19652540
references.citation: Mol Cell Biol. 2008 May;28(10):3114-26
references.pmid: 18332108
references.citation: Cell. 1994 Mar 25;76(6):1013-23
references.pmid: 8137420
references.citation: J Biol Chem. 2008 Jun 6;283(23):15568-76
references.pmid: 18420587
references.citation: Mol Cell Biol. 2004 Nov;24(21):9327-38
references.pmid: 15485902
references.citation: Cancer Res. 2006 Feb 15;66(4):2162-72
references.pmid: 16489017
references.citation: Mol Cell Biol. 2004 Feb;24(3):985-96
references.pmid: 14729947
references.citation: Mol Cell Biol. 2006 Dec;26(23):9016-34
references.pmid: 17015463
references.citation: Biochem Biophys Res Commun. 2004 Aug 27;321(3):675-80
references.pmid: 15358159
references.citation: Nucleic Acids Res. 1995 Oct 11;23(19):3974-9
references.pmid: 7479045
references.citation: Int J Oncol. 2002 Jan;20(1):201-5
references.pmid: 11743665
references.citation: Cell Signal. 2006 Nov;18(11):2041-8
references.pmid: 16725311
references.citation: Biochem J. 2000 Aug 1;349 Pt 3:765-73
references.pmid: 10903137
references.citation: Mol Cell Biol. 2008 Dec;28(23):7050-65
references.pmid: 18809582
references.citation: Zhonghua Yi Xue Za Zhi. 2002 Jul 25;82(14):974-8
references.pmid: 12181092
references.citation: J Biol Chem. 2005 Feb 18;280(7):5496-502
references.pmid: 15596447
references.citation: Carcinogenesis. 2010 Feb;31(2):302-10
references.pmid: 19933706
references.citation: Naunyn Schmiedebergs Arch Pharmacol. 1999 Dec;360(6):683-90
references.pmid: 10619186
references.citation: Genes Dev. 1997 Apr 1;11(7):847-62
references.pmid: 9106657
references.citation: Nat Cell Biol. 2002 Jul;4(7):529-33
references.pmid: 12080348
references.citation: J Biol Chem. 2008 Feb 29;283(9):5728-37
references.pmid: 18165222
references.citation: Nucleic Acids Res. 2009 Mar;37(4):e31
references.pmid: 19179371
references.citation: J Cell Biochem. 2003 Dec 15;90(6):1140-8
references.pmid: 14635188
references.citation: Cell Cycle. 2009 Mar 15;8(6):889-95
references.pmid: 19221506
references.citation: Exp Cell Res. 2007 Jan 1;313(1):65-76
references.pmid: 17069796