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Mollstedt J, Mansouri L, Rosenquist R. Precision diagnostics in chronic lymphocytic leukemia: Past, present and future. Front Oncol 2023; 13:1146486. [PMID: 37035166 PMCID: PMC10080996 DOI: 10.3389/fonc.2023.1146486] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/10/2023] [Indexed: 04/11/2023] Open
Abstract
Genetic diagnostics of hematological malignancies has evolved dramatically over the years, from chromosomal banding analysis to next-generation sequencing, with a corresponding increased capacity to detect clinically relevant prognostic and predictive biomarkers. In diagnostics of patients with chronic lymphocytic leukemia (CLL), we currently apply fluorescence in situ hybridization (FISH)-based analysis to detect recurrent chromosomal aberrations (del(11q), del(13q), del(17p) and trisomy 12) as well as targeted sequencing (IGHV and TP53 mutational status) for risk-stratifying purposes. These analyses are performed before start of any line of treatment and assist in clinical decision-making including selection of targeted therapy (BTK and BCL2 inhibitors). Here, we present the current view on the genomic landscape of CLL, including an update on recent advances with potential for clinical translation. We discuss different state-of-the-art technologies that are applied to enable precision diagnostics in CLL and highlight important genomic markers with current prognostic and/or predictive impact as well as those of prospective clinical relevance. In the coming years, it will be important to develop more comprehensive genomic analyses that can capture all types of relevant genetic aberrations, but also to develop highly sensitive assays to detect minor mutations that affect therapy response or confer resistance to targeted therapies. Finally, we will bring up the potential of new technologies and multi-omics analysis to further subclassify the disease and facilitate implementation of precision medicine approaches in this still incurable disease.
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Affiliation(s)
- John Mollstedt
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Larry Mansouri
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Richard Rosenquist
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Clinical Genetics, Karolinska University Hospital, Solna, Sweden
- *Correspondence: Richard Rosenquist,
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Five Percent Variant Allele Frequency Is a Reliable Reporting Threshold for TP53 Variants Detected by Next Generation Sequencing in Chronic Lymphocytic Leukemia in the Clinical Setting. Hemasphere 2022; 6:e761. [PMID: 35935605 PMCID: PMC9348859 DOI: 10.1097/hs9.0000000000000761] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 07/06/2022] [Indexed: 11/28/2022] Open
Abstract
The clinical significance of small TP53 clones detected with next generation sequencing (NGS) in chronic lymphocytic leukemia is an issue of active debate. According to the official guidelines, treatment decisions should be guided only by variants with variant allele frequency (VAF) ≥10%. We present data on 325 consecutive patients with chronic lymphocytic leukemia analyzed with NGS. In total 47 pathogenic/likely pathogenic (P/LP), TP53 variants were detected in 26 patients (8%). Eleven of these (23%) were in the 5% to 10% VAF range and reported according to our institutional policy. All TP53 variants in the 5% to 10% VAF range were confirmed (100% concordance) with a second NGS panel. Our results where further validated with the performance of Sanger sequencing and digital droplet PCR (ddPCR). In 12 patients with available fluorescence in situ hybridization data and TP53 mutations within 5% to 10% VAF, deletion of chromosome 17p (del(17p)) was detectable in only 1 patient. We propose a robust diagnostic algorithm, which allows the safe detection and reporting of TP53 variants with VAF down to 5% in the clinical setting. Our study provides evidence that NGS is equally potent to detect variants with VAF 5% to 10% compared to those with VAF 10% to 15%, highlighting the urgent need for harmonization of NGS methodologies across diagnostic laboratories.
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Sutton LA, Ljungström V, Enjuanes A, Cortese D, Skaftason A, Tausch E, Stano Kozubik K, Nadeu F, Armand M, Malcikova J, Pandzic T, Forster J, Davis Z, Oscier D, Rossi D, Ghia P, Strefford JC, Pospisilova S, Stilgenbauer S, Davi F, Campo E, Stamatopoulos K, Rosenquist R, On Behalf Of The European Research Initiative On Cll Eric. Comparative analysis of targeted next-generation sequencing panels for the detection of gene mutations in chronic lymphocytic leukemia: an ERIC multi-center study. Haematologica 2021; 106:682-691. [PMID: 32273480 PMCID: PMC7927885 DOI: 10.3324/haematol.2019.234716] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Indexed: 12/12/2022] Open
Abstract
Next-generation sequencing (NGS) has transitioned from research to clinical routine, yet the comparability of different technologies for mutation profiling remains an open question. We performed a European multicenter (n=6) evaluation of three amplicon-based NGS assays targeting 11 genes recurrently mutated in chronic lymphocytic leukemia. Each assay was assessed by two centers using 48 pre-characterized chronic lymphocytic leukemia samples; libraries were sequenced on the Illumina MiSeq instrument and bioinformatics analyses were centralized. Across all centers the median percentage of target reads ≥100x ranged from 94.2-99.8%. In order to rule out assay-specific technical variability, we first assessed variant calling at the individual assay level i.e., pairwise analysis of variants detected amongst partner centers. After filtering for variants present in the paired normal sample and removal of PCR/sequencing artefacts, the panels achieved 96.2% (Multiplicom), 97.7% (TruSeq) and 90% (HaloPlex) concordance at a variant allele frequency (VAF) >0.5%. Reproducibility was assessed by looking at the inter-laboratory variation in detecting mutations and 107 of 115 (93% concordance) mutations were detected by all six centers, while the remaining eight variants (7%) were undetected by a single center. Notably, 6 of 8 of these variants concerned minor subclonal mutations (VAF <5%). We sought to investigate low-frequency mutations further by using a high-sensitivity assay containing unique molecular identifiers, which confirmed the presence of several minor subclonal mutations. Thus, while amplicon-based approaches can be adopted for somatic mutation detection with VAF >5%, after rigorous validation, the use of unique molecular identifiers may be necessary to reach a higher sensitivity and ensure consistent and accurate detection of low-frequency variants.
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Affiliation(s)
- Lesley-Ann Sutton
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Viktor Ljungström
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden,Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Anna Enjuanes
- Institut d’Investigacions Biomèdiques August Pi iSunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain and Hospital Clínic of Barcelona, Universitat de Barcelona, Barcelona, Spain
| | - Diego Cortese
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Aron Skaftason
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Eugen Tausch
- Department of Internal Medicine III, Ulm University,Ulm, Germany
| | - Katerina Stano Kozubik
- Center of Molecular Medicine, CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Ferran Nadeu
- Institut d’Investigacions Biomèdiques August Pi iSunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain and Hospital Clínic of Barcelona, Universitat de Barcelona, Barcelona, Spain
| | - Marine Armand
- AP-HP, Hopital Pitie-Salpetriere, Department of Hematology, Sorbonne Université, Paris, France
| | - Jikta Malcikova
- Center of Molecular Medicine, CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Tatjana Pandzic
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Jade Forster
- Cancer Sciences, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Zadie Davis
- Department of Hematology, Royal Bournemouth Hospital, Bournemouth, UK
| | - David Oscier
- Department of Hematology, Royal Bournemouth Hospital, Bournemouth, UK
| | - Davide Rossi
- Hematology Department, Oncology Institute of Southern Switzerland and Institute of Oncology Research, Bellinzona, Switzerland
| | - Paolo Ghia
- Division of Experimental Oncology, Università Vita-Salute San Raffaele and IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Jonathan C Strefford
- Cancer Sciences, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Sarka Pospisilova
- Center of Molecular Medicine, CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | | | - Frederic Davi
- AP-HP, Hopital Pitie-Salpetriere, Department of Hematology, Sorbonne Université, Paris, France
| | - Elias Campo
- Institut d’Investigacions Biomèdiques August Pi iSunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid, Spain and Hospital Clínic of Barcelona, Universitat de Barcelona, Barcelona, Spain
| | - Kostas Stamatopoulos
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden,Institute of Applied Biosciences, Center for Research and Technology, Thessaloniki, Greec
| | - Richard Rosenquist
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden,Clinical Genetics, Karolinska University Laboratory, Karolinska University Hospital, Stockholm, Sweden
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Yao H, Wu C, Chen Y, Guo L, Chen W, Pan Y, Fu X, Wang G, Ding Y. Spectrum of gene mutations identified by targeted next-generation sequencing in Chinese leukemia patients. Mol Genet Genomic Med 2020; 8:e1369. [PMID: 32638549 PMCID: PMC7507579 DOI: 10.1002/mgg3.1369] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 05/23/2020] [Accepted: 05/28/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Despite targeted sequencing have identified several mutations for leukemia, there is still a limit of mutation screening for Chinese leukemia. Here, we used targeted next-generation sequencing for testing the mutation patterns of Chinese leukemia patients. METHODS We performed targeted sequencing of 504 tumor-related genes in 109 leukemia samples to identify single-nucleotide variants (SNVs) and insertions and deletions (INDELs). Pathogenic variants were assessed based on the American College of Medical Genetics and Genomics (ACMG) guidelines. The functional impact of pathogenic genes was explored through gene ontology (GO), pathway analysis, and protein-protein interaction network in silico. RESULTS We identified a total of 4,655 SNVs and 614 INDELs in 419 genes, in which PDE4DIP, NOTCH2, FANCA, BCR, and ROS1 emerged as the highly mutated genes. Of note, we were the first to demonstrate an association of PDE4DIP mutation and leukemia. Based on ACMG guidelines, 39 pathogenic and likely pathogenic mutations in 27 genes were found. GO annotation showed that the biological process including gland development, leukocyte differentiation, respiratory system development, myeloid leukocyte differentiation, mesenchymal to epithelial transition, and so on were involved. CONCLUSION Our study provided a map of gene mutations in Chinese patients with leukemia and gave insights into the molecular pathogenesis of leukemia.
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Affiliation(s)
- Hongxia Yao
- Department of Hematology, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, Hainan, P.R. China
| | - Congming Wu
- Department of Hematology, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, Hainan, P.R. China
| | - Yueqing Chen
- Hainan General Hospital, University of South China, Haikou, Hainan, China
| | - Li Guo
- Department of Hematology, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, Hainan, P.R. China
| | - Wenting Chen
- Department of Hematology, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, Hainan, P.R. China
| | - Yanping Pan
- Department of Hematology, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, Hainan, P.R. China
| | - Xiangjun Fu
- Department of Hematology, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, Hainan, P.R. China
| | - Guyun Wang
- Department of Hematology, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, Hainan, P.R. China
| | - Yipeng Ding
- Department of General Practice, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, Hainan, P.R. China
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Mareckova A, Malcikova J, Tom N, Pal K, Radova L, Salek D, Janikova A, Moulis M, Smardova J, Kren L, Mayer J, Trbusek M. ATM and TP53 mutations show mutual exclusivity but distinct clinical impact in mantle cell lymphoma patients. Leuk Lymphoma 2019; 60:1420-1428. [DOI: 10.1080/10428194.2018.1542144] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Andrea Mareckova
- Department of Internal Medicine - Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Jitka Malcikova
- Department of Internal Medicine - Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Nikola Tom
- Central European Institute of Technology (CEITEC), Center of Molecular Medicine, Masaryk University, Brno, Czech Republic
| | - Karol Pal
- Central European Institute of Technology (CEITEC), Center of Molecular Medicine, Masaryk University, Brno, Czech Republic
| | - Lenka Radova
- Central European Institute of Technology (CEITEC), Center of Molecular Medicine, Masaryk University, Brno, Czech Republic
| | - David Salek
- Department of Internal Medicine - Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Andrea Janikova
- Department of Internal Medicine - Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Mojmir Moulis
- Department of Pathology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Jana Smardova
- Department of Pathology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Leos Kren
- Department of Pathology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Jiri Mayer
- Department of Internal Medicine - Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Martin Trbusek
- Department of Internal Medicine - Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic
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Sutton LA, Rosenquist R. Deciphering the molecular landscape in chronic lymphocytic leukemia: time frame of disease evolution. Haematologica 2015; 100:7-16. [PMID: 25552678 DOI: 10.3324/haematol.2014.115923] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Dramatic advances in next generation sequencing technologies have provided a novel opportunity to understand the molecular genetics of chronic lymphocytic leukemia through the comprehensive detection of genetic lesions. While progress is being made in elucidating the clinical significance of recurrently mutated genes, layers of complexity have been added to our understanding of chronic lymphocytic leukemia pathogenesis in the guise of the molecular evolution and (sub)clonal architecture of the disease. As we prepare for an era of tailored therapy, we need to appreciate not only the effect mutations have on drug response but also the impact subclones containing specific mutations have at initial presentation, during therapy and upon relapse. Therefore, although the wealth of emerging genetic data has great potential in helping us devise strategies to improve the therapy and prognosis of patients, focused efforts will be required to follow disease evolution, particularly in the context of novel therapies, in order to translate this knowledge into clinical settings.
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Affiliation(s)
- Lesley-Ann Sutton
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Sweden
| | - Richard Rosenquist
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Sweden
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Sutton LA, Rosenquist R. The complex interplay between cell-intrinsic and cell-extrinsic factors driving the evolution of chronic lymphocytic leukemia. Semin Cancer Biol 2015; 34:22-35. [DOI: 10.1016/j.semcancer.2015.04.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 04/24/2015] [Accepted: 04/27/2015] [Indexed: 01/08/2023]
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Sutton LA, Ljungström V, Mansouri L, Young E, Cortese D, Navrkalova V, Malcikova J, Muggen AF, Trbusek M, Panagiotidis P, Davi F, Belessi C, Langerak AW, Ghia P, Pospisilova S, Stamatopoulos K, Rosenquist R. Targeted next-generation sequencing in chronic lymphocytic leukemia: a high-throughput yet tailored approach will facilitate implementation in a clinical setting. Haematologica 2014; 100:370-6. [PMID: 25480502 DOI: 10.3324/haematol.2014.109777] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Next-generation sequencing has revealed novel recurrent mutations in chronic lymphocytic leukemia, particularly in patients with aggressive disease. Here, we explored targeted re-sequencing as a novel strategy to assess the mutation status of genes with prognostic potential. To this end, we utilized HaloPlex targeted enrichment technology and designed a panel including nine genes: ATM, BIRC3, MYD88, NOTCH1, SF3B1 and TP53, which have been linked to the prognosis of chronic lymphocytic leukemia, and KLHL6, POT1 and XPO1, which are less characterized but were found to be recurrently mutated in various sequencing studies. A total of 188 chronic lymphocytic leukemia patients with poor prognostic features (unmutated IGHV, n=137; IGHV3-21 subset #2, n=51) were sequenced on the HiSeq 2000 and data were analyzed using well-established bioinformatics tools. Using a conservative cutoff of 10% for the mutant allele, we found that 114/180 (63%) patients carried at least one mutation, with mutations in ATM, BIRC3, NOTCH1, SF3B1 and TP53 accounting for 149/177 (84%) of all mutations. We selected 155 mutations for Sanger validation (variant allele frequency, 10-99%) and 93% (144/155) of mutations were confirmed; notably, all 11 discordant variants had a variant allele frequency between 11-27%, hence at the detection limit of conventional Sanger sequencing. Technical precision was assessed by repeating the entire HaloPlex procedure for 63 patients; concordance was found for 77/82 (94%) mutations. In summary, this study demonstrates that targeted next-generation sequencing is an accurate and reproducible technique potentially suitable for routine screening, eventually as a stand-alone test without the need for confirmation by Sanger sequencing.
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Affiliation(s)
- Lesley-Ann Sutton
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Sweden
| | - Viktor Ljungström
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Sweden
| | - Larry Mansouri
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Sweden
| | - Emma Young
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Sweden
| | - Diego Cortese
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Sweden
| | - Veronika Navrkalova
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Jitka Malcikova
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Alice F Muggen
- Department of Immunology, Erasmus MC, University Medical Center Rotterdam, The Netherlands
| | - Martin Trbusek
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | | | - Frederic Davi
- Laboratory of Hematology and Universite Pierre et Marie Curie, Hopital Pitie-Salpetriere, Paris, France
| | | | - Anton W Langerak
- Department of Immunology, Erasmus MC, University Medical Center Rotterdam, The Netherlands
| | - Paolo Ghia
- Università Vita-Salute San Raffaele, Milan, Italy Division of Molecular Oncology and Department of Onco-Hematology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Sarka Pospisilova
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Kostas Stamatopoulos
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Sweden Institute of Applied Biosciences, CERTH, Thessaloniki, Greece Hematology Department and HCT Unit, G. Papanicolaou Hospital, Thessaloniki, Greece
| | - Richard Rosenquist
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Sweden
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Deneberg S, Kanduri M, Ali D, Bengtzen S, Karimi M, Qu Y, Kimby E, Mansouri L, Rosenquist R, Lennartsson A, Lehmann S. microRNA-34b/c on chromosome 11q23 is aberrantly methylated in chronic lymphocytic leukemia. Epigenetics 2014; 9:910-7. [PMID: 24686393 DOI: 10.4161/epi.28603] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
A commonly deleted region in chronic lymphocytic leukemia (CLL) is the 11q22-23 region, which encompasses the ATM gene. Evidence suggests that tumor suppressor genes other than ATM are likely to be involved in CLL with del(11q). A microRNA (miR) cluster including the miR-34b and miR-34c genes is located, among other genes, within the commonly deleted region (CDR) at 11q. Interestingly, these miRs are part of the TP53 network and have been shown to be epigenetically regulated. In this study, we investigated the expression and methylation status of these miRs in a well-characterized cohort of CLL, including cases with/without 11q-deletion. We show that the miR-34b/c promoter was aberrantly hypermethylated in a large proportion of CLL cases (48%, 25/52 cases). miR-34b/c expression correlated inversely to DNA methylation (P = 0.003), and presence of high H3K37me3 further suppressed expression regardless of methylation status. Furthermore, increased miR-34b/c methylation inversely correlated with the presence of 11q-deletion, indicating that methylation and del(11q) independently silence these miRs. Finally, 5-azacytidine and trichostatin A exposure synergistically increased the expression of miR-34b/c in CLL cells, and transfection of miR-34b or miR-34c into HG3 CLL cells significantly increased apoptosis. Altogether, our novel data suggest that miR-34b/c is a candidate tumor suppressor that is epigenetically silenced in CLL.
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Affiliation(s)
- Stefan Deneberg
- Department of Internal Medicine/Hematology; Karolinska Institutet; Karolinska University Hospital Huddinge; Stockholm, Sweden
| | - Meena Kanduri
- Institute of Biomedicine; Department of Clinical Chemistry and Transfusion Medicine; Sahlgrenska University Hospital; Göteborg, Sweden
| | - Dina Ali
- Department of Internal Medicine/Hematology; Karolinska Institutet; Karolinska University Hospital Huddinge; Stockholm, Sweden
| | - Sofia Bengtzen
- Department of Internal Medicine/Hematology; Karolinska Institutet; Karolinska University Hospital Huddinge; Stockholm, Sweden
| | - Mohsen Karimi
- Department of Internal Medicine/Hematology; Karolinska Institutet; Karolinska University Hospital Huddinge; Stockholm, Sweden
| | - Ying Qu
- Department of Internal Medicine/Hematology; Karolinska Institutet; Karolinska University Hospital Huddinge; Stockholm, Sweden
| | - Eva Kimby
- Department of Internal Medicine/Hematology; Karolinska Institutet; Karolinska University Hospital Huddinge; Stockholm, Sweden
| | - Larry Mansouri
- Department of Immunology, Genetics and Pathology; Science for Life Laboratory; Uppsala University; Uppsala, Sweden
| | - Richard Rosenquist
- Department of Immunology, Genetics and Pathology; Science for Life Laboratory; Uppsala University; Uppsala, Sweden
| | - Andreas Lennartsson
- Department of Biomedicine and Nutrition; NOVUM; Karolinska Institutet; Stockholm, Sweden
| | - Sören Lehmann
- Department of Internal Medicine/Hematology; Karolinska Institutet; Karolinska University Hospital Huddinge; Stockholm, Sweden
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