title: Human Cdc45 is a proliferation-associated antigen.
abstract: Cell division cycle protein 45 (Cdc45) plays a critical role in DNA replication to ensure that chromosomal DNA is replicated only once per cell cycle. We analysed the expression of human Cdc45 in proliferating and nonproliferating cells. Our findings show that Cdc45 protein is absent from long-term quiescent, terminally differentiated and senescent human cells, although it is present throughout the cell cycle of proliferating cells. Moreover, Cdc45 is much less abundant than the minichromosome maintenance (Mcm) proteins in human cells, supporting the concept that origin binding of Cdc45 is rate limiting for replication initiation. We also show that the Cdc45 protein level is consistently higher in human cancer-derived cells compared with primary human cells. Consequently, tumour tissue is preferentially stained using Cdc45-specific antibodies. Thus, Cdc45 expression is tightly associated with proliferating cell populations and Cdc45 seems to be a promising candidate for a novel proliferation marker in cancer cell biology.
authors.affiliation:  Leibniz Institute for Age Research, Fritz Lipmann Institute, Jena, Germany Radiation Oncology and Biology, University of Oxford, UK  Institute of Pathology, Bad Berka, Germany  National University of Ireland, Department of Biochemistry, Galway, Ireland Center for Molecular Biomedicine, Friedrich Schiller University, Jena, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Pollok
authors.affiliation:  Leibniz Institute for Age Research, Fritz Lipmann Institute, Jena, Germany Radiation Oncology and Biology, University of Oxford, UK  Institute of Pathology, Bad Berka, Germany  National University of Ireland, Department of Biochemistry, Galway, Ireland Center for Molecular Biomedicine, Friedrich Schiller University, Jena, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Bauerschmidt
authors.affiliation:  Leibniz Institute for Age Research, Fritz Lipmann Institute, Jena, Germany Radiation Oncology and Biology, University of Oxford, UK  Institute of Pathology, Bad Berka, Germany  National University of Ireland, Department of Biochemistry, Galway, Ireland Center for Molecular Biomedicine, Friedrich Schiller University, Jena, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Sänger
authors.affiliation:  Leibniz Institute for Age Research, Fritz Lipmann Institute, Jena, Germany Radiation Oncology and Biology, University of Oxford, UK  Institute of Pathology, Bad Berka, Germany  National University of Ireland, Department of Biochemistry, Galway, Ireland Center for Molecular Biomedicine, Friedrich Schiller University, Jena, Germany.
authors.forename: H-P
authors.initials: HP
authors.lastname: Nasheuer
authors.affiliation:  Leibniz Institute for Age Research, Fritz Lipmann Institute, Jena, Germany Radiation Oncology and Biology, University of Oxford, UK  Institute of Pathology, Bad Berka, Germany  National University of Ireland, Department of Biochemistry, Galway, Ireland Center for Molecular Biomedicine, Friedrich Schiller University, Jena, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Grosse
mesh_terms: D000941:Antigens / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D014408:Biomarkers, Tumor; D018797:Cell Cycle Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism*; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D016922:Cellular Senescence / Q000502:physiology; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism
chemical_list: D000941:Antigens; D014408:Biomarkers, Tumor; C113571:CDC45 protein, human; D018797:Cell Cycle Proteins; D019394:Ki-67 Antigen; D018809:Proliferating Cell Nuclear Antigen