title: Assessment of p53 and ATM functionality in chronic lymphocytic leukemia by multiplex ligation-dependent probe amplification.
abstract: The ATM-p53 DNA-damage response (DDR) pathway has a crucial role in chemoresistance in CLL, as indicated by the adverse prognostic impact of genetic aberrations of TP53 and ATM. Identifying and distinguishing TP53 and ATM functional defects has become relevant as epigenetic and posttranscriptional dysregulation of the ATM/p53 axis is increasingly being recognized as the underlying cause of chemoresistance. Also, specific treatments sensitizing TP53- or ATM-deficient CLL cells are emerging. We therefore developed a new ATM-p53 functional assay with the aim to (i) identify and (ii) distinguish abnormalities of TP53 versus ATM and (iii) enable the identification of additional defects in the ATM-p53 pathway. Reversed transcriptase multiplex ligation-dependent probe amplification (RT-MLPA) was used to measure ATM and/or p53-dependent genes at the RNA level following DNA damage using irradiation. Here, we showed that this assay is able to identify and distinguish three subgroups of CLL tumors (i.e., TP53-defective, ATM-defective and WT) and is also able to detect additional samples with a defective DDR, without molecular aberrations in TP53 and/or ATM. These findings make the ATM-p53 RT-MLPA functional assay a promising prognostic tool for predicting treatment responses in CLL.
authors.affiliation: 1] Department of Hematology, Academic Medical Center, Amsterdam, The Netherlands [2] Laboratory of Experimental Immunology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: G D
authors.initials: GD
authors.lastname: te Raa
authors.affiliation: Bioinformatics Laboratory, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: P D
authors.initials: PD
authors.lastname: Moerland
authors.affiliation: 1] Department of Hematology, Academic Medical Center, Amsterdam, The Netherlands [2] Laboratory of Experimental Immunology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: A C
authors.initials: AC
authors.lastname: Leeksma
authors.affiliation: Laboratory of Experimental Immunology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: I A
authors.initials: IA
authors.lastname: Derks
authors.affiliation: MRC-Holland, Amsterdam, The Netherlands.
authors.forename: H
authors.initials: H
authors.lastname: Yigittop
authors.affiliation: MRC-Holland, Amsterdam, The Netherlands.
authors.forename: N
authors.initials: N
authors.lastname: Laddach
authors.affiliation: MRC-Holland, Amsterdam, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Loden-van Straaten
authors.affiliation: Department of Molecular Medicine, Central European Institute of Technology, Masaryk University, Brno, Czech Republic.
authors.forename: V
authors.initials: V
authors.lastname: Navrkalova
authors.affiliation: Department of Molecular Medicine, Central European Institute of Technology, Masaryk University, Brno, Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Trbusek
authors.affiliation: 1] Department of Hematology, Academic Medical Center, Amsterdam, The Netherlands [2] Laboratory of Experimental Immunology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: D M
authors.initials: DM
authors.lastname: Luijks
authors.affiliation: Department of Translational Oncology, National Center for Tumor Diseases (NCT), German Cancer Research Center (DKFZ) and Department of Medicine V, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Zenz
authors.affiliation: School of Cancer Sciences, University of Birmingham, Birmingham, UK.
authors.forename: A
authors.initials: A
authors.lastname: Skowronska
authors.affiliation: Department of Hematology, Medical Center Leeuwarden, Leeuwarden, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Hoogendoorn
authors.affiliation: School of Cancer Sciences, University of Birmingham, Birmingham, UK.
authors.forename: T
authors.initials: T
authors.lastname: Stankovic
authors.affiliation: 1] Department of Hematology, Academic Medical Center, Amsterdam, The Netherlands [2] LYMMCARE (Lymphoma and Myeloma Center), Amsterdam, The Netherlands.
authors.forename: M H
authors.initials: MH
authors.lastname: van Oers
authors.affiliation: 1] Laboratory of Experimental Immunology, Academic Medical Center, Amsterdam, The Netherlands [2] LYMMCARE (Lymphoma and Myeloma Center), Amsterdam, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Eldering
authors.affiliation: 1] Department of Hematology, Academic Medical Center, Amsterdam, The Netherlands [2] Laboratory of Experimental Immunology, Academic Medical Center, Amsterdam, The Netherlands [3] LYMMCARE (Lymphoma and Myeloma Center), Amsterdam, The Netherlands.
authors.forename: A P
authors.initials: AP
authors.lastname: Kater
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D064007:Ataxia Telangiectasia Mutated Proteins / Q000235:genetics* / Q000378:metabolism; D001681:Biological Assay; D004249:DNA Damage; D004317:Doxorubicin / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm / Q000235:genetics; D044127:Epigenesis, Genetic; D005720:Gamma Rays; D015973:Gene Expression Regulation, Leukemic; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D060885:Multiplex Polymerase Chain Reaction / Q000379:methods*; D009154:Mutation; D012334:RNA, Neoplasm / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism; D014740:Vidarabine / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D012334:RNA, Neoplasm; D016159:Tumor Suppressor Protein p53; D004317:Doxorubicin; C576324:ATM protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; D014740:Vidarabine; C024352:fludarabine