title: Dysregulation of cell cycle control caused by overexpression of the oncogene pp32r1 (ANP32C) and the Tyr>His mutant pp32r1Y140H.
abstract: The pp32 (ANP32A) gene acts as a tumor suppressor while its closely related homologue pp32r1 (ANP32C) is oncogenic and is overexpressed in breast, prostate and pancreatic tumors. The transduction of p53wt cell lines (ACHN and HeLa) with pp32r1 or pp32r1Y140H lentivirus increased the proliferation of p53wt cell lines compared to the untransduced control cells while transduction of the p53(R248W) MiaPaCa2 cell line had no effect. Cell cycle analysis of transduced ACHN cells by PI staining and BrdU incorporation illustrated a pronounced shift toward the S-phase of the cell cycle in cells overexpressing the pp32r1 and pp32r1Y140H proteins. Confocal microscopy and western blotting demonstrated that pp32r1 and the pp32r1Y140H mutant protein reside predominantly in the cytoplasm in constrast to pp32 which is a nuclear/cytoplasmic shuttling protein. To determine the effects of pp32r1 or pp32r1Y140H overexpression at the proteomic level we performed a comprehensive proteome analysis on ACHN, ACHN-pp32r1 and ACHN-pp32r1Y140H cell lysates using the isotope-coded protein label (ICPL) method. Among those proteins with >40% regulation were Macrophage Capping protein (CAPG) and Chromodomain Helicase DNA binding protein 4 (CHD4) proteins which were significantly upregulated by pp32r1 and pp32r1Y140H overexpression. This increase in CHD4 also appears to influence a number of cell cycle regulator genes including; p53, p21 and cyclinD1 as judged by western blotting. Silencing of CHD4 in ACHN-pp32r1Y140H cells using specific shRNA reverted the cell cycle dysregulation caused by pp32r1Y140H expression to that of the untransduced ACHN cell line, suggesting that CHD4 is the prominent effector of the pp32r1/pp32r1Y140H phenotype.
authors: Institute for Transfusion Medicine, Hannover Medical School, Hannover, Germany.
authors: Salma
authors: S
authors: Buddaseth
authors: Wiebke
authors: W
authors: Göttmann
authors: Rainer
authors: R
authors: Blasczyk
authors: Trevor
authors: T
authors: Huyton
mesh_terms: D001324:Autoantigens / Q000235:genetics / Q000378:metabolism; D059447:Cell Cycle Checkpoints / Q000235:genetics*; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D049109:Cell Proliferation; D019938:Cyclin D1 / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D016147:Genes, Tumor Suppressor; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D056245:Mi-2 Nucleosome Remodeling and Deacetylase Complex / Q000235:genetics / Q000378:metabolism; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D009857:Oncogenes; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: C087425:ANP32A protein, human; C489949:ANP32C protein, human; D001324:Autoantigens; C115323:CHD4 protein, human; D047908:Intracellular Signaling Peptides and Proteins; D050505:Mutant Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D016601:RNA-Binding Proteins; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D019938:Cyclin D1; D056245:Mi-2 Nucleosome Remodeling and Deacetylase Complex