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Significance of genetic polymorphisms in hematological malignancies: implications of risk factors for prognosis and relapse. MEMO-MAGAZINE OF EUROPEAN MEDICAL ONCOLOGY 2018. [DOI: 10.1007/s12254-018-0446-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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2
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Abstract
Acute lymphoblastic leukemia (ALL) is characterized by a great biological and clinical heterogeneity. Despite most adult patients enter complete hematologic remission after induction therapy only 40% survive five or more years. Over the last 20 years, the definition of an accurate biologic leukemia profile and the minimal residual disease evaluation in addition to conventional risk criteria led to a significant improvement for the risk stratification. The alterations of the oncosuppressor gene TP53, including deletions, sequence mutations and defect in its expression due to regulatory defects, define a new important predictor of adverse outcome. More recently, new drugs have been developed with the aim of targeting p53 protein itself or its regulatory molecules, such as Mdm2, and restoring the pathway functionality. Therefore, TP53 alterations should be considered in the diagnostic work-up to identify high risk ALL patients in need of intensive treatment strategies or eligible for new innovative targeted therapies.
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Affiliation(s)
- Silvia Salmoiraghi
- a Hematology and Bone Marrow Transplant Unit of Azienda Ospedaliera Papa Giovanni XXIII , Bergamo , Italy
| | - Alessandro Rambaldi
- a Hematology and Bone Marrow Transplant Unit of Azienda Ospedaliera Papa Giovanni XXIII , Bergamo , Italy.,b Department of Hematology-Oncology , University of Milan , Milan , Italy
| | - Orietta Spinelli
- a Hematology and Bone Marrow Transplant Unit of Azienda Ospedaliera Papa Giovanni XXIII , Bergamo , Italy
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3
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TP53 mutations occur in 15.7% of ALL and are associated with MYC-rearrangement, low hypodiploidy, and a poor prognosis. Blood 2014; 124:251-8. [PMID: 24829203 DOI: 10.1182/blood-2014-02-558833] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
TP53 is the most extensively studied gene in cancer. However, data on frequency and the prognostic impact of TP53 mutations in acute lymphoblastic leukemia (ALL) remain scarce. Thus, we aimed at identifying the mutation frequency of TP53, its association with cytogenetic subgroups, and its impact on survival in a large cohort of 625 patients with ALL. Our data revealed an overall mutation incidence of 15.7%, which increases with age. Correlation with cytogenetic subgroups showed that mutations were most frequent in ALL with low hypodiploidy or MYC-rearrangements. Furthermore, for a large number of patients, both TP53 alleles were altered, either by 2 TP53 mutations (12%) or by a TP53 mutation and a TP53 deletion in the second allele (39%). A high TP53 mutation load was correlated to low hypodiploidy, high hyperdiploidy, and a complex karyotype. Moreover, a higher mutation load was found in B-lineage ALL compared with T-lineage ALL. Similar to other cancers, the median overall survival was significantly shorter in patients with TP53 mutation compared with patients with wild-type TP53. This effect was especially pronounced when both TP53 alleles were affected, either by 2 TP53 mutations or by both a mutation and an accompanying TP53 deletion.
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4
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Malcikova J, Pavlova S, Kozubik KS, Pospisilova S. TP53 Mutation Analysis in Clinical Practice: Lessons From Chronic Lymphocytic Leukemia. Hum Mutat 2014; 35:663-71. [DOI: 10.1002/humu.22508] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 01/03/2014] [Indexed: 01/22/2023]
Affiliation(s)
- Jitka Malcikova
- Central European Institute of Technology; Center of Molecular Medicine, and Faculty of Medicine; Department of Internal Medicine - Hematology and Oncology; Masaryk University; Brno Czech Republic
| | - Sarka Pavlova
- Central European Institute of Technology; Center of Molecular Medicine, and Faculty of Medicine; Department of Internal Medicine - Hematology and Oncology; Masaryk University; Brno Czech Republic
| | - Katerina Stano Kozubik
- Central European Institute of Technology; Center of Molecular Medicine, and Faculty of Medicine; Department of Internal Medicine - Hematology and Oncology; Masaryk University; Brno Czech Republic
| | - Sarka Pospisilova
- Central European Institute of Technology; Center of Molecular Medicine, and Faculty of Medicine; Department of Internal Medicine - Hematology and Oncology; Masaryk University; Brno Czech Republic
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5
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Abdel-Aziz MM. Clinical significance of serum p53 and epidermal growth factor receptor in patients with acute leukemia. Asian Pac J Cancer Prev 2013; 14:4295-9. [PMID: 23991992 DOI: 10.7314/apjcp.2013.14.7.4295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pretreatment serum p53 and epidermal growth factor receptor (EGFR) were assessed using enzyme-linked immunosorbent assay (ELISA) in patients with acute leukemia to analysis their roles in characterization of different subtypes of the disease. MATERIALS AND METHODS Serum samples from thirty two patients with acute myeloid leukemia (AML) and fourteen patients with acute lymphoid leukemia (ALL) were analysed, along with 24 from healthy individuals used as a control group. RESULTS The results demonstrated a significant increase of serum p53 and EGFR in patients with AML (p<0.0001) compared to the control group. Also, the results showed a significant increase of both markers in patients with ALL (p<0.05, p<0.0001 respectively). Sensitivities and specificities for these variables were 52% and 100% for p53, and 73.9%, 95.8% for EGFR. Serum p53 and EGFR could successfully differentiate between M4 and other AML subtypes, while these variables failed to discriminate among ALL subtypes. A positive significant correlation was noted between p53 and EGFR. Negative significant correlations were observed between these variables and both of hemoglobin (Hg) content and RBC count. CONCLUSIONS Mutant p53 and EGFR are helpful serological markers for diagnosis of patients with AML or ALL and can aid in characterization of disease. Moreover, these markers may reflect carcinogenesis mechanisms.
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Abstract
TP53’s role as guardian of the genome diminishes with age, as the probability of mutation increases. Previous studies have shown an association between p53 gene mutations and cancer. However, the role of somatic TP53 mutations in the steep rise in cancer rates with aging has not been investigated at a population level. This relationship was quantified using the International Agency for Research on Cancer (IARC) TP53 and GLOBOCAN cancer databases. The power function exponent of the cancer rate was calculated for 5-y age-standardized incidence or mortality rates for up to 25 cancer sites occurring in adults of median age 42 to 72 y. Linear regression analysis of the mean percentage of a cancer’s TP53 mutations and the corresponding cancer exponent was conducted for four populations: worldwide, Japan, Western Europe, and the United States. Significant associations (P ≤ 0.05) were found for incidence rates but not mortality rates. Regardless of the population studied, positive associations were found for all cancer sites, with more significant associations for solid tumors, excluding the outlier prostate cancer or sex-related tumors. Worldwide and Japanese populations yielded P values as low as 0.002 and 0.005, respectively. For the United States, a significant association was apparent only when analysis utilized the Surveillance, Epidemiology, and End Results (SEER) database. This study found that TP53 mutations accounts for approximately one-quarter and one-third of the aging-related rise in the worldwide and Japanese incidence of all cancers, respectively. These significant associations between TP53 mutations and the rapid rise in cancer incidence with aging, considered with previously published literature, support a causal role for TP53 according to the Bradford-Hill criteria. However, questions remain concerning the contribution of TP53 mutations to neoplastic development and the role of factors such as genetic instability, obesity, and gene deficiencies other than TP53 that reduce p53 activity.
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Affiliation(s)
- Richard B Richardson
- Radiological Protection Research and Instrumentation Branch; Atomic Energy of Canada Limited; Chalk River Laboratories; Chalk River, ON Canada
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Chiaretti S, Brugnoletti F, Tavolaro S, Bonina S, Paoloni F, Marinelli M, Patten N, Bonifacio M, Kropp MG, Sica S, Guarini A, Foà R. TP53 mutations are frequent in adult acute lymphoblastic leukemia cases negative for recurrent fusion genes and correlate with poor response to induction therapy. Haematologica 2013; 98:e59-61. [PMID: 23403321 DOI: 10.3324/haematol.2012.076786] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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8
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Ibrahem WN, Hasony HJ, Hassan JG. Frequency of Mutant p53 Among Acute Lymphoblastic Leukemia Patients in Basrah, Iraq. Qatar Med J 2012. [DOI: 10.5339/qmj.2012.1.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
A study was carried out to investigate the status of p53 proteins and their relation to the occurrence of TEL-AML-1 translocation in children with acute lymphoblastic leukemia (ALL) attending the oncology unit at Basrah maternity and children hospital during the period from May 2009 to April 2010. A total of 100 blood samples were collected from 40 newly diagnosed ALL cases, and 60 healthy children served as controls. Anti-p53 antibody was detected by an enzyme-linked immunosorbent assay (ELISA), and TEL-AML-1 fusion gene was determined by reversetranscriptase polymerase reaction (RT-PCR) on RNA extracted from fresh blood samples. The overall proportion of anti-p53 was 20% in the leukemic patients, whereas none of the healthy control group showed anti-p53 positivity. This difference was statistically significant (P < 0.05). According to the French-American-British (FAB) classification, 75% of the anti-p53 positive cases were classified as L2 stage ALL. There was a significant difference (P < 0.05) between standard and high-risk groups of ALL patients in the frequency of anti-p53: 40% of high-risk group members had anti-p53 compared to 8% in the standard risk patients. There was no association (P>0.05) between TEL-AML-1 translocation and anti-p53. None of the standard risk patients with positive TEL-AML-1 fusion gene displayed the anti-p53 while 33.3% of TEL-AML-1 positive with high risk displayed the antip53 antibody.
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Affiliation(s)
| | | | - JG Hassan
- **Department of Pediatrics, College of Medicine, University of Basrah, Basrah, Iraq
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9
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Sahu G, Jena RK. Clinical significance of P53 and Bcl-2 in acute myeloid leukemia patients of Eastern India. Hematol Rep 2011; 3:e28. [PMID: 22593819 PMCID: PMC3269804 DOI: 10.4081/hr.2011.e28] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 09/24/2011] [Accepted: 11/24/2011] [Indexed: 01/10/2023] Open
Abstract
The frequency of p53 and Bcl-2 protein expression in 100 newly diagnosed and 10 relapsed acute myeloid leukemia (AML) patients was analyzed by immunocytochemistry (ICC). The Kaplan-Meier method was used for univariate and multivariate statistical analysis to assess the relationship between p53, Bcl-2 and clinico-hematologic feature with respect to overall survival (OS) using SPSS statistical software. No statistical significance was found in univariate analysis (P=0.60). However, when the subgroups of patients (+1, +2, +3 and +4) were compared, expression of p53 and Bcl-2 protein (1-10%, 11-30%, 31-50% and >50%) was statistically significant (P<0.05). However, in multivariate analysis, p53, immunopositivity was independently associated with a shorter overall survival (OS) (P=0.038) while Bcl-2 immunopositivity was associated with longer overall survival (OS) (P=0.002). Our finding shows that p53 and Bcl-2 protein overexpression is a strong indicator of response to chemotherapy and overall survival. This study reports for the first time AML in patients from Eastern India.
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Affiliation(s)
- Geetaram Sahu
- Molecular Oncology and Medical Biotechnology Division, Institute of Life Sciences, Chandrasekharpur, Bhubaneswar, Orissa
| | - Rabindra kumar Jena
- Dept of Clinical Haematology, S.C.B Medical College Hospital, Cuttack, Orissa, India
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Szczepanek J, Styczyński J, Haus O, Tretyn A, Wysocki M. Relapse of acute lymphoblastic leukemia in children in the context of microarray analyses. Arch Immunol Ther Exp (Warsz) 2011; 59:61-8. [PMID: 21246408 DOI: 10.1007/s00005-010-0110-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Accepted: 08/19/2010] [Indexed: 10/18/2022]
Abstract
Over the last four decades the treatment of patients with newly diagnosed childhood acute lymphoblastic leukemia (ALL) has improved remarkably. However, still about 20% of children with ALL relapse despite risk-adapted polychemotherapy. The prognosis of relapsed ALL is relatively poor, even with modern aggressive chemotherapy. Identification of the biological and genetic mechanisms contributing to recurrence in patients with ALL is critical for the development of effective therapeutic strategies to treat refractory leukemic patients. Allogeneic hematopoietic stem-cell transplantation is the treatment of choice for many children with relapsed ALL. The gene expression profile obtained by microarray technology could provide important determinants of the drug response and clinical outcome in childhood ALL. Incorporation of the data on expression levels of newly identified genes into existing strategies of risk stratification might improve clinical management. Current microarray data show correlation of in vitro drug resistance with significant patterns of gene expression and explain clinical differences between early and late relapse. Genes involved in cell proliferation, self-renewal and differentiation, protein biosynthesis, carbohydrate metabolism, and DNA replication and repair are usually among those highly expressed in relapsed lymphoblasts. Current status and future perspectives of microarray data on gene expression and drug resistance profile in relapsed pediatric ALL are discussed in this review.
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Affiliation(s)
- Joanna Szczepanek
- Department of Pediatric Hematology and Oncology, Collegium Medicum, Nicolaus Copernicus University, Curie-Skłodowskiej 9, 85-094, Bydgoszcz, Poland
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Shuga J, Zeng Y, Novak R, Mathies RA, Hainaut P, Smith MT. Selected technologies for measuring acquired genetic damage in humans. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2010; 51:851-870. [PMID: 20872848 DOI: 10.1002/em.20630] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Technical advances have improved the capacity to detect and quantify genetic variants, providing novel methods for the detection of rare mutations and for better understanding the underlying environmental factors and biological mechanisms contributing to mutagenesis. The polymerase chain reaction (PCR) has revolutionized genetic testing and remains central to many of these new techniques for mutation detection. Millions of genetic variations have been discovered across the genome. These variations include germline mutations and polymorphisms, which are inherited in a Mendelian manner and present in all cells, as well as acquired, somatic mutations that differ widely by type and size [from single-base mutations to whole chromosome rearrangements, and including submicroscopic copy number variations (CNVs)]. This review focuses on current methods for assessing acquired somatic mutations in the genome, and it examines their application in molecular epidemiology and sensitive detection and analysis of disease. Although older technologies have been exploited for detecting acquired mutations in cancer and other disease, the high-throughput and high-sensitivity offered by next-generation sequencing (NGS) systems are transforming the discovery of disease-associated acquired mutations by enabling comparative whole-genome sequencing of diseased and healthy tissues from the same individual. Emerging microfluidic technologies are beginning to facilitate single-cell genetic analysis of target variable regions for investigating cell heterogeneity within tumors as well as preclinical detection of disease. The technologies discussed in this review will significantly expand our knowledge of acquired genetic mutations and causative mechanisms.
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Affiliation(s)
- Joe Shuga
- School of Public Health, University of California, Berkeley, California 94720, USA
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12
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Abstract
Resistance to chemotherapy in ovarian cancer is poorly understood. Evolutionary models of cancer predict that, following treatment, resistance emerges either because of outgrowth of an intrinsically resistant sub-clone or evolves in residual disease under the selective pressure of treatment. To investigate genetic evolution in high-grade serous (HGS) ovarian cancers, we first analysed cell line series derived from three cases of HGS carcinoma before and after platinum resistance had developed (PEO1, PEO4 and PEO6; PEA1 and PEA2; and PEO14 and PEO23). Analysis with 24-colour fluorescence in situ hybridisation and single nucleotide polymorphism (SNP) array comparative genomic hybridisation (CGH) showed mutually exclusive endoreduplication and loss of heterozygosity events in clones present at different time points in the same individual. This implies that platinum-sensitive and -resistant disease was not linearly related, but shared a common ancestor at an early stage of tumour development. Array CGH analysis of six paired pre- and post-neoadjuvant treatment HGS samples from the CTCR-OV01 clinical study did not show extensive copy number differences, suggesting that one clone was strongly dominant at presentation. These data show that cisplatin resistance in HGS carcinoma develops from pre-existing minor clones but that enrichment for these clones is not apparent during short-term chemotherapy treatment.
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Abstract
In each major theory of the origin of cancer-field theory, chemical carcinogenesis, infection, mutation, or epigenetic change-the tissue stem cell is involved in the generation of cancer. Although the cancer type is identified by the more highly differentiated cells in the cancer cell lineage or hierarchy (transit-amplifying cells), the property of malignancy and the molecular lesion of the cancer exist in the cancer stem cell. In the case of teratocarcinomas, normal germinal stem cells have the potential to become cancers if placed in an environment that allows expression of the cancer phenotype (field theory). In cancers due to chemically induced mutations, viral infections, somatic and inherited mutations, or epigenetic changes, the molecular lesion or infection usually first occurs in the tissue stem cells. Cancer stem cells then give rise to transit-amplifying cells and terminally differentiated cells, similar to what happens in normal tissue renewal. However, the major difference between cancer growth and normal tissue renewal is that whereas normal transit amplifying cells usually differentiate and die, at various levels of differentiation, the cancer transit-amplifying cells fail to differentiate normally and instead accumulate (ie, they undergo maturation arrest), resulting in cancer growth.
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Affiliation(s)
- Stewart Sell
- Wadsworth Center and Ordway Research Institute, Empire State Plaza, Albany, NY 12201, USA.
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Case M, Matheson E, Minto L, Hassan R, Harrison CJ, Bown N, Bailey S, Vormoor J, Hall AG, Irving JAE. Mutation of genes affecting the RAS pathway is common in childhood acute lymphoblastic leukemia. Cancer Res 2008; 68:6803-9. [PMID: 18701506 DOI: 10.1158/0008-5472.can-08-0101] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Deregulation of the RAS-RAF-mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK)-ERK signaling cascade is often caused by somatic mutations in genes encoding proteins which influence the activity of this pathway and include NRAS, KRAS2, FLT3, PTPN11, and BRAF. We report the first comprehensive mutational screen of key exons of these genes in a large cohort of unselected acute lymphoblastic leukemia (ALL) cases at diagnosis (n = 86) and in a more selected cohort at disease recurrence (n = 47) using the sensitive method of denaturing high-performance liquid chromatography. We show that somatic mutations that deregulate the pathway constitute one of the most common genetic aberrations in childhood ALL (cALL), being found in 35% of diagnostic and 25% of relapse samples. In matched presentation/relapse pairs, mutations predominating at relapse could be shown to be present at very low levels at diagnosis using allele-specific PCR, thus implicating the mutated clone in disease progression. Importantly, in primary samples, we show that mutations are associated with activated ERK and differential cytotoxicity to MEK-ERK inhibitors was shown for some patients. Inhibitors of the pathway, which are currently undergoing clinical trial, may be a novel therapeutic option for cALL, particularly at relapse.
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Affiliation(s)
- Marian Case
- Northern Institute for Cancer Research, Newcastle upon Tyne, Tyne and Wear, United Kingdom
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Horsley SW, Mackay A, Iravani M, Fenwick K, Valgeirsson H, Dexter T, Ashworth A, Kearney L. Array CGH of fusion gene-positive leukemia-derived cell lines reveals cryptic regions of genomic gain and loss. Genes Chromosomes Cancer 2006; 45:554-64. [PMID: 16523483 DOI: 10.1002/gcc.20317] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Human leukemia-derived cell lines containing characteristic chromosomal translocations and inversions have been instrumental in identifying fusion genes implicated in the pathogenesis of the corresponding leukemia. Although chimeric fusion genes usually provide early and essential steps in the development of leukemia, they are not in themselves sufficient, requiring additional genetic events. The nature of these secondary, cooperating genetic events is not known. The advent of genome wide microarray-based methods for assessing copy number changes made it possible to search for cytogenetically invisible regions of chromosome imbalance. We used BAC microarrays with a resolution of 1 Mb to determine whether cryptic regions of deletion or gain were associated with specific leukemia-associated fusion genes in a series of cell lines. To complement the array analysis, we also applied 24-color karyotyping by M-FISH. This revealed cryptic chromosomal translocations and regions of loss or gain in all the cell lines studied. The chromosomal origin of previously unidentified marker chromosomes was revealed. In all cases, chromosomes described as monosomic were shown to be involved in unbalanced translocations with concurrent loss and/or gain of chromosomal material. The extent of these amplified and deleted regions was more accurately defined. Finally, small regions of deletion and amplification, often including genes known to be involved in leukemia progression (for example MYC, TP53, CDKN2A, and KIT), were identified.
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Affiliation(s)
- Sharon W Horsley
- Section of Haemato-Oncology, Institute of Cancer Research, London, United Kingdom
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Beesley AH, Cummings AJ, Freitas JR, Hoffmann K, Firth MJ, Ford J, de Klerk NH, Kees UR. The gene expression signature of relapse in paediatric acute lymphoblastic leukaemia: implications for mechanisms of therapy failure. Br J Haematol 2005; 131:447-56. [PMID: 16281934 DOI: 10.1111/j.1365-2141.2005.05785.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Despite significant improvements in the treatment of childhood acute lymphoblastic leukaemia (ALL), the prognosis for relapsing patients remains poor. The aim of this study was to generate a transcriptional profile of relapsed ALL to increase our understanding of the mechanisms involved in therapy failure. RNA was extracted from 11 pairs of cryopreserved pre-B ALL bone marrow specimens taken from the same patients at diagnosis and relapse, and analysed using HG-U133A microarrays. Relapse specimens overexpressed genes that are involved with cell growth and proliferation, in keeping with their aggressive phenotype. When tested in 72 independent specimens of pre-B ALL and T-ALL, the identified genes could successfully differentiate between diagnosis and relapse in either lineage, indicating the existence of relapse mechanisms common to both. These genes have functions relevant for oncogenesis, drug resistance and metastasis, but are not related to classical multidrug-resistance pathways. Increased expression of the top-ranked gene (BSG) at diagnosis was significantly associated with adverse outcome. Several chromosomal loci, including 19p13, were identified as potential hotspots for aberrant gene expression in relapsed ALL. Our results provide evidence for a link between drug resistance and the microenvironment that has previously only been considered in the context of solid tumour biology.
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Affiliation(s)
- Alex H Beesley
- Division of Children's Leukaemia and Cancer Research, Telethon Institute for Child Health Research, University of Western Australia, Perth, WA, Australia
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Shih LY, Huang CF, Wu JH, Wang PN, Lin TL, Dunn P, Chou MC, Kuo MC, Tang CC. Heterogeneous patterns of FLT3 Asp(835) mutations in relapsed de novo acute myeloid leukemia: a comparative analysis of 120 paired diagnostic and relapse bone marrow samples. Clin Cancer Res 2004; 10:1326-32. [PMID: 14977832 DOI: 10.1158/1078-0432.ccr-0835-03] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE We analyzed Asp(835) mutations of FLT3 on paired marrow samples at diagnosis and relapse from 120 adult patients with de novo acute myeloid leukemia (AML) to determine the role of FLT3 Asp(835) mutation in the relapse of AML. EXPERIMENTAL DESIGN Asp(835) mutation was analyzed by DNA PCR amplification of exon 20 of FLT3 gene followed by EcoRV digestion. All of the mutations were confirmed by sequence analysis. Mutant to wild-type allelic ratio was determined by Genescan analysis. The Expand Long Template PCR System was used to determine the allelic location of internal tandem duplication of FLT3 (FLT3/ITD) and Asp(835) mutations. RESULTS Thirteen patients had Asp(835) mutations at diagnosis, of them 8 lost the mutations at relapse, and the remaining 5 patients carrying Asp(835) mutations at diagnosis relapsed with the identical mutation types. Another 6 patients acquired Asp(835) mutations at relapse. Five samples harbored both FLT3/ITD and Asp(835) mutations that were found on different alleles by cloning analysis in the 3 patients studied. There were no differences in WBC count, French-American-British subtype, percentage of marrow blasts, or circulating blasts between patients with and without Asp(835) mutations, whereas the difference in the prevalence of Asp(835) mutations among cytogenetic/molecular subgroups was statistically significant (P = 0.025). CONCLUSIONS The present study showed that patients with AML had heterogeneous patterns of FLT3 Asp(835) mutations, either acquisition or loss of the mutations at relapse. Asp(835) mutant clone may develop as a secondary event in a subset of patients with AML.
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Affiliation(s)
- Lee-Yung Shih
- Department of Internal Medicine, Chang Gung Memorial Hospital, Taipei, and Chang Gung University, Taoyuan, Taiwan.
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Weston VJ, Austen B, Wei W, Marston E, Alvi A, Lawson S, Darbyshire PJ, Griffiths M, Hill F, Mann JR, Moss PAH, Taylor AMR, Stankovic T. Apoptotic resistance to ionizing radiation in pediatric B-precursor acute lymphoblastic leukemia frequently involves increased NF-kappaB survival pathway signaling. Blood 2004; 104:1465-73. [PMID: 15142883 DOI: 10.1182/blood-2003-11-4039] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
To investigate possible causes of the variable response to treatment in pediatric B-precursor acute lymphoblastic leukemia (ALL) and to establish potential novel therapeutic targets, we used ionizing radiation (IR) exposure as a model of DNA damage formation to identify tumors with resistance to p53-dependent apoptosis. Twenty-one of 40 ALL tumors responded normally to IR, exhibiting accumulation of p53 and p21 proteins and cleavage of caspases 3, 7, and 9 and of PARP1. Nineteen tumors exhibited apoptotic resistance and lacked PARP1 and caspase cleavage; although 15 of these tumors had normal accumulation of p53 and p21 proteins, examples exhibited abnormal expression of TRAF5, TRAF6, and cIAP1 after IR, suggesting increased NF-kappaB prosurvival signaling as the mechanism of apoptotic resistance. The presence of a hyperactive PARP1 mutation in one tumor was consistent with such increased NF-kappaB activity. PARP1 inhibition restored p53-dependent apoptosis after IR in these leukemias by reducing NF-kappaB DNA binding and transcriptional activity. In the remaining 4 ALL tumors, apoptotic resistance was associated with a TP53 mutation or with defective activation of p53. We conclude that increased NF-kappaB prosurvival signaling is a frequent mechanism by which B-precursor ALL tumors develop apoptotic resistance to IR and that PARP1 inhibition may improve the DNA damage response of these leukemias.
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Affiliation(s)
- Victoria J Weston
- Cancer Research UK Institute for Cancer Studies, Birmingham University, Edgbaston, Birmingham, B15 2TT, United Kingdom.
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Suarez CR, Bertolone SJ, Raj AB, Coventry S. Second malignant neoplasms in childhood acute lymphoblastic leukemia: primitive neuroectodermal tumor of the chest wall with germline p53 mutation as a second malignant neoplasm. Am J Hematol 2004; 76:52-6. [PMID: 15114597 DOI: 10.1002/ajh.20012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
About 80% of children treated for acute lymphoblastic leukemia (ALL) will be long-term survivors. Second malignant neoplasm (SMNs) are a devastating sequelae observed on these children, with an estimated cumulative risk of 2-3.3% fifteen years after diagnosis. Primitive neuroectodermal tumor of bone (PNET) is rarely observed as a SMN following treatment of childhood ALL. The authors described the occurrence of a chest wall PNET of the bone at the site of a central line placement associated with both germ-line and tumor cell p53 mutation in a 8-year-old boy 1 year after completing therapy for standard risk ALL. A review of the literature of 25,051 children treated for ALL discovered 230 SMNs (0.99%), and only one case of PNET of the bone was noted among this group. The occurrence of a SMN in children treated for ALL is a rare event. Such an occurrence, in particular the development of an unusual SMN, should be evaluated for a germline p53 mutation.
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MESH Headings
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Child, Preschool
- Combined Modality Therapy
- Humans
- Male
- Mutation
- Neoplasms, Second Primary/genetics
- Neoplasms, Second Primary/pathology
- Neoplasms, Second Primary/therapy
- Neuroectodermal Tumors, Primitive, Peripheral/genetics
- Neuroectodermal Tumors, Primitive, Peripheral/pathology
- Neuroectodermal Tumors, Primitive, Peripheral/therapy
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology
- Thoracic Wall/metabolism
- Thoracic Wall/pathology
- Treatment Outcome
- Tumor Suppressor Protein p53/genetics
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Affiliation(s)
- Carlos R Suarez
- Department of Pediatrics, Section of Hematology/Oncology, University of Louisville School of Medicine, Louisville, Kentucky, USA.
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20
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Narendran A, Ganjavi H, Morson N, Connor A, Barlow JW, Keystone E, Malkin D, Freedman MH. Mutant p53 in bone marrow stromal cells increases VEGF expression and supports leukemia cell growth. Exp Hematol 2003; 31:693-701. [PMID: 12901974 DOI: 10.1016/s0301-472x(03)00159-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Genetic alterations, including p53 mutations, have been identified in the stroma of solid tumors and are thought be involved in the induction of tumor growth and metastasis. We tested the hypothesis that somatic molecular alterations in bone marrow stromal cells provide a favorable growth environment for leukemic cells. MATERIALS AND METHODS We established an in vitro model consisting of stroma expressing mutant p53 (Cys135Ser) to study its ability to support growth of cells from a pre-B acute lymphoblastic leukemia (ALL) cell line. Normal and leukemic bone marrow stromal cells were screened for p53 mutations by mutant-specific ELISA, SSCP, and direct sequencing. Secretion of vascular endothelial growth factor (VEGF) was measured by quantitative ELISA. RESULTS Transfection of stromal cells with mutant p53 increased synthesis of VEGF and supported the growth of leukemic cells. An ELISA-based assay suggested the occurrence of in vivo p53 alterations in bone marrow stromal cells from 2 of 12 ALL patients screened. Direct sequencing of one of these samples revealed a somatic heterozygous p53 gene mutation (Asp49His). This sample secreted more VEGF and provided increased growth support to leukemic cells. The ability of Asp 49His-p53 to increase the expression of VEGF was confirmed with transfection experiments in a p53-null cell line. CONCLUSION Our findings indicate that genetic alterations, such as p53 mutations, in stromal cells can increase stromal-derived support of leukemia growth. Increased synthesis of pro-angiogenic cytokines, such as VEGF, may constitute one possible pathway by which this process is mediated.
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Affiliation(s)
- Aru Narendran
- Southern Alberta Children's Cancer Program, Alberta Children's Hospital, Calgary, Alberta, Canada
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21
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Foroni L, Hoffbrand AV. Molecular analysis of minimal residual disease in adult acute lymphoblastic leukaemia. Best Pract Res Clin Haematol 2002; 15:71-90. [PMID: 11987917 DOI: 10.1053/beha.2002.0186] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Despite intensive chemotherapy and stem cell transplantation (SCT) programmes, overall survival in adult acute lymphoblastic leukaemia (ALL) remains poor compared to that in childhood ALL. Despite clinical and morphological remission being achieved by over 80% of patients, 5-year survival is limited to 40% of patients, clearly indicating that morphology is insufficient in predicting future outcome. Molecular assessment of residual disease in bone marrow using immunoglobulin genes as markers of clonality has recently been evaluated in a large adult ALL study in our institution. Analysis of disease-free survival (DFS) rates for minimal residual disease-(MRD-) positive and -negative patients established that MRD positivity was associated with increased relapse rates at all times, being most significant at 3-5 months post-induction and beyond. Pre-autologous SCT tests are predictive of outcome, but for allogeneic SCT outcome is related to results of the tests after the procedure rather than before. The association of MRD test results and DFS was independent of, and greater than, other standard predictors of outcome and is therefore important in determining treatment for individual patients.
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Affiliation(s)
- Letizia Foroni
- Haematology Department, Royal Free & University College School of Medicine, Royal Free Campus, Pond Street, London NW3 2QG, UK
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22
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Styczynski J, Wysocki M. In vitro drug resistance profiles of adult acute lymphoblastic leukemia: possible explanation for difference in outcome to similar therapeutic regimens. Leuk Lymphoma 2002; 43:301-7. [PMID: 11999561 DOI: 10.1080/10428190290006071] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Age has important prognostic impact in acute lymphoblastic leukemia (ALL). Adults with ALL have a worse prognosis compared to children. This may be due to different, unfavorable biology, poor treatment tolerance, drug resistance, higher expression of drug resistance related proteins. The lymphoblasts from adult ALL show an increased in vitro resistance to cytotoxic drugs, including prednisolone, dexamethasone, cytosine arabinoside, daunorubicin, L-asparaginase and methotrexate. Glucocorticoid resistance may be a fundamental difference between children, adolescents and adults with ALL, which may underlie different biological aspects and also explain the difference in prognosis. It seems that in vitro resistance to prednisolone with respect to the age might be a continuous variable in ALL patients, except infants. The greater the age, the higher the in vitro resistance to prednisolone. This may be due to induction of various defense mechanisms, such as an activation of P-glycoprotein, which develops throughout the life and protect the human against xenobiotics. Among a number of various drug resistance mechanisms, only several weak differences between adults and children with ALL have been reported including higher P-glycoprotein expression, lower methotrexate polyglutamate accumulation and possibly more often p53 gene mutations in adults. Intrinsic resistance, induction of drug resistance proteins expression during chemotherapy and co-existence of various mechanisms are common phenomena in adult ALL. It seems that age itself, more than drug resistance profile, reflects factors which have direct effect on chemotherapy response in adult ALL.
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Affiliation(s)
- Jan Styczynski
- Department of Pediatric Hematology and Oncology, Medical University, Bydgoszcz, Poland.
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23
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Gump J, McGavran L, Wei Q, Hunger SP. Analysis of TP53 mutations in relapsed childhood acute lymphoblastic leukemia. J Pediatr Hematol Oncol 2001; 23:416-9. [PMID: 11878574 DOI: 10.1097/00043426-200110000-00005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
TP53 is the most commonly mutated gene in human cancer, but TP53 mutations are present in less than 5% of children with acute lymphoblastic leukemia (ALL) at initial presentation. Mutations are detected more frequently in children with relapsed T-cell ALL, but the potential role of TP53 mutations in relapsed B-lineage childhood ALL is not understood as well. The authors determined the nucleotide sequence of amplified DNA from exons 5 to 8 of the TP53 gene in leukemic cells obtained from 17 children with ALL at the time of first bone marrow relapse. All 17 contained only germline TP53 sequences. Review of the published literature disclosed that TP53 mutations have been found in 22% of cases of relapsed ALL. To understand the role of p53 abnormalities in this clinical setting, it will be important for future studies to analyze cases of relapsed ALL with assays capable of interrogating the functional integrity of the p53 pathway.
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Affiliation(s)
- J Gump
- Department of Pediatrics, University of Colorado School of Medicine, Denver, USA
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24
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Moreira I, Papaioannou M, Mortuza FY, Gameiro P, Palmisano GL, Harrison CJ, Prentice HG, Mehta AB, Hoffbrand AV, Foroni L. Heterogeneity of VH-JH gene rearrangement patterns: an insight into the biology of B cell precursor ALL. Leukemia 2001; 15:1527-36. [PMID: 11587210 DOI: 10.1038/sj.leu.2402234] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Oligoclonal B cell proliferation, as defined by the presence of more than one leukemic clone, has been detected in approximately 20% to 30% of patients with acute lymphoblastic leukemia (ALL) using PCR or Southern blotting. An accurate assessment of these populations is required to avoid false negative measurements of minimal residual disease (MRD) in follow-up bone marrow (BM) samples of ALL patients. In this study, we analysed 29 ALL patients with two or more immunoglobulin heavy (IGH) chain gene rearrangements in the presentation samples using IGH fingerprinting PCR and sequence analysis. Thirty-nine (51%) of 76 sequences (from 15 patients), shared no VNDNJ homology (ie different CDR3 regions). In the remaining 14 patients, at least two related VH sequences were identified in each patient (identical DNJ sequences). Numerical abnormalities of chromosome 14 was detected in 10 patients. Eight patients were analysed at presentation and relapse. In four of them, expansion of a minor presentation-clone was detected at relapse while the major presentation clone disappeared, confirming 'subclonal evolution'. Finally, in our cohort of patients, the presence of related or unrelated IGH clones did not influence overall survival.
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Affiliation(s)
- I Moreira
- Haematology Department, Royal Free and University College School of Medicine, London, UK
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25
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Tentori L, Portarena I, Bonmassar E, Graziani G. Combined effects of adenovirus-mediated wild-type p53 transduction, temozolomide and poly (ADP-ribose) polymerase inhibitor in mismatch repair deficient and non-proliferating tumor cells. Cell Death Differ 2001; 8:457-69. [PMID: 11423906 DOI: 10.1038/sj.cdd.4400832] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2000] [Revised: 10/30/2000] [Accepted: 12/15/2000] [Indexed: 01/17/2023] Open
Abstract
Lack of p53 or mismatch repair (MR) function and scarce cell proliferation are commonly associated with tumor cell resistance to antineoplastic agents. Recently, inhibition of poly(ADP-ribose) polymerase (PARP) has been considered as a tool to overcome resistance of MR-deficient tumors to methylating agents. In the present study we demonstrated that infection with p53 expressing adenovirus (Ad-p53), enhances chemosensitivity of MR-deficient tumor cell lines to the methylating agent temozolomide (TZM), either used as single agent or, more efficiently, when combined with PARP inhibitor. Moreover, the association of Ad-p53 with drug treatment induced a more pronounced growth inhibitory effect than that provoked by Ad-p53 infection only. Cells, growth arrested by p53 transduction, and then subsequently exposed to the drugs, were still highly susceptible to cytotoxicity induced by TZM and PARP inhibitor. The results suggested that this drug combination might be effective even in non-proliferating tumor cells. It is conceivable to envisage future possible strategies to enhance cytostatic or cytotoxic effects induced by Ad-p53, based on the use of TZM, alone or combined with PARP inhibitor for the therapy of resistant tumors.
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Affiliation(s)
- L Tentori
- Pharmacology and Medical Oncology Section, Department of Neuroscience, University of Rome Tor Vergata, Via di Tor Vergata 135, 00133 Rome, Italy
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26
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Abstract
Relapse, a major obstacle in the treatment of acute leukemia, is essentially caused by re-growth of residual leukemia cells, frequently accompanied by resistance to chemotherapy. Comparative studies of clones both at initial diagnosis and at subsequent relapse have indicated that phenotype and karyotype are frequently changed at relapse. This can be recognized as the result of negative selection by chemotherapy in a heterogeneous population. Furthermore, complex molecular alterations that include the loss of as well as the acquisition of mutations are noticed by comparing multiple genes associated with leukemia, suggesting a continuous genetic evolution. Studies on leukemia relapse have thus served as a model of clonal progression, which can be serially observed, including selection by chemotherapy, induction of resistant phenotype, and genetic alteration.
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Affiliation(s)
- T Naoe
- Department of Infectious Diseases, Nagoya University School of Medicine, Nagoya 466-8560, Japan.
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27
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Microsatellite Instability and p53 Mutations Are Associated With Abnormal Expression of the MSH2 Gene in Adult Acute Leukemia. Blood 1999. [DOI: 10.1182/blood.v94.2.733] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractMicrosatellite instability (MSI) and p53 mutations have been reported to occur in a significant proportion of patients with therapy-related acute myeloid leukemia (AML). MSH2 is one of the genes involved in DNA mismatch repair to maintain fidelity of genomic replication, and defects of MSH2 are directly involved in MSI in hereditary nonpolyposis colorectal tumors and other human tumors. We have examined the expression of MSH2 protein by Western blotting in 43 adult leukemia samples, including 42 AML and 1 acute lymphoblastic leukemia (ALL) using the antibody MSH2 (Ab-1) (Calbiochem, La Jolla, CA). Abnormal expression of MSH2 protein was found in 14 of 43 (32.6%) cases; a control antibody to actin was always positive. Of the 14 patients that had abnormal expression of MSH2, 2 had therapy-related acute leukemia and 9 were elderly patients (>60 years of age). Expression of MSH2 mRNA was further examined by reverse transcriptase-polymerase chain reaction (RT-PCR). Deletion of MSH2 mRNA was found in 1 of 14 cases with deficient MSH2 protein expression. This group of patients was also screened for loss of heterozygosity (LOH) at the MSH2 locus using a panel 4 microsatellite markers (D2S367, D2S288, D2S391, and D2S2294). LOH was found in 5 of 11 cases examined. There was no evidence of LOH in 14 patients with normal MSH2 expression who were examined using the same markers. Functional evidence for defective DNA mismatch repair in leukemic cells lacking MSH2 as manifest by MSI was found in 7 of 11 cases studied. Mutations of the p53 gene in these 43 samples were also investigated by direct sequencing of full-length p53 cDNA. Mutations of p53 were found in 6 of 43 cases, including 5 of the 14 (35.7%) cases that did not express MSH2 protein. In contrast, mutation of p53 was only found in 1 of 29 (3.4%) cases with normal MSH2 protein expression (χ2 = 5.720, P < .02). These results suggest that abnormalities of DNA mismatch repair due to defective MSH2 expression could play a key role in leukemogenesis, in particular in AML arising in elderly patients or secondary to previous chemotherapy.
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28
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Microsatellite Instability and p53 Mutations Are Associated With Abnormal Expression of the MSH2 Gene in Adult Acute Leukemia. Blood 1999. [DOI: 10.1182/blood.v94.2.733.414k03_733_740] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microsatellite instability (MSI) and p53 mutations have been reported to occur in a significant proportion of patients with therapy-related acute myeloid leukemia (AML). MSH2 is one of the genes involved in DNA mismatch repair to maintain fidelity of genomic replication, and defects of MSH2 are directly involved in MSI in hereditary nonpolyposis colorectal tumors and other human tumors. We have examined the expression of MSH2 protein by Western blotting in 43 adult leukemia samples, including 42 AML and 1 acute lymphoblastic leukemia (ALL) using the antibody MSH2 (Ab-1) (Calbiochem, La Jolla, CA). Abnormal expression of MSH2 protein was found in 14 of 43 (32.6%) cases; a control antibody to actin was always positive. Of the 14 patients that had abnormal expression of MSH2, 2 had therapy-related acute leukemia and 9 were elderly patients (>60 years of age). Expression of MSH2 mRNA was further examined by reverse transcriptase-polymerase chain reaction (RT-PCR). Deletion of MSH2 mRNA was found in 1 of 14 cases with deficient MSH2 protein expression. This group of patients was also screened for loss of heterozygosity (LOH) at the MSH2 locus using a panel 4 microsatellite markers (D2S367, D2S288, D2S391, and D2S2294). LOH was found in 5 of 11 cases examined. There was no evidence of LOH in 14 patients with normal MSH2 expression who were examined using the same markers. Functional evidence for defective DNA mismatch repair in leukemic cells lacking MSH2 as manifest by MSI was found in 7 of 11 cases studied. Mutations of the p53 gene in these 43 samples were also investigated by direct sequencing of full-length p53 cDNA. Mutations of p53 were found in 6 of 43 cases, including 5 of the 14 (35.7%) cases that did not express MSH2 protein. In contrast, mutation of p53 was only found in 1 of 29 (3.4%) cases with normal MSH2 protein expression (χ2 = 5.720, P < .02). These results suggest that abnormalities of DNA mismatch repair due to defective MSH2 expression could play a key role in leukemogenesis, in particular in AML arising in elderly patients or secondary to previous chemotherapy.
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