scholarly journals Megakaryocytes, erythropoietic and granulopoietic cells express CAL2 antibody in myeloproliferative neoplasms carrying CALR gene mutations

2020 ◽  
Vol 102 (1) ◽  
pp. 45-50
Author(s):  
Hebah Ali ◽  
Ignazio Puccio ◽  
Ayse U. Akarca ◽  
Roshanak Bob ◽  
Sabine Pomplun ◽  
...  
Keyword(s):  
Myeloproliferative Neoplasms ◽  
Gene Mutations

scholarly journals The Prevalence of TET2 Gene Mutations in Patients with BCR-ABL-Negative Myeloproliferative Neoplasms (MPN): A Systematic Review and Meta-Analysis

Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 3078
Author(s):  
Yuh Cai Chia ◽  
Md Asiful Islam ◽  
Phil Hider ◽  
Peng Yeong Woon ◽  
Muhammad Farid Johan ◽  
...  
Keyword(s):  
Regional Differences ◽  
Myeloproliferative Neoplasms ◽  
Meta Analysis ◽  
Gene Mutations ◽  
Screening Methods ◽  
Eligibility Criteria ◽  
Pooled Prevalence ◽  
Critical Appraisal Tool ◽  
Appraisal Tool

Multiple recurrent somatic mutations have recently been identified in association with myeloproliferative neoplasms (MPN). This meta-analysis aims to assess the pooled prevalence of TET2 gene mutations among patients with MPN. Six databases (PubMed, Scopus, ScienceDirect, Google Scholar, Web of Science and Embase) were searched for relevant studies from inception till September 2020, without language restrictions. The eligibility criteria included BCR-ABL-negative MPN adults with TET2 gene mutations. A random-effects model was used to estimate the pooled prevalence with 95% confidence intervals (CIs). Subgroup analyses explored results among different continents and countries, WHO diagnostic criteria, screening methods and types of MF. Quality assessment was undertaken using the Joanna Briggs Institute critical appraisal tool. The study was registered with PROSPERO (CRD42020212223). Thirty-five studies were included (n = 5121, 47.1% female). Overall, the pooled prevalence of TET2 gene mutations in MPN patients was 15.5% (95% CI: 12.1–19.0%, I2 = 94%). Regional differences explained a substantial amount of heterogeneity. The prevalence of TET2 gene mutations among the three subtypes PV, ET and MF were 16.8%, 9.8% and 15.7%, respectively. The quality of the included studies was determined to be moderate–high among 83% of the included studies. Among patients with BCR-ABL-negative MPN, the overall prevalence of TET2 gene mutations was 15.5%.

scholarly journals The Importance of Identification of M-BCRABL Oncogene and JAK2V617F Mutation in Myeloproliferative Neoplasms

2014 ◽  
Vol 60 (2) ◽  
pp. 44-48
Author(s):  
Annamária Szántó ◽  
Zsuzsanna Pap ◽  
Z Pávai ◽  
I Benedek ◽  
Judit Beáta Köpeczi ◽  
...  
Keyword(s):  
Molecular Markers ◽  
Molecular Biology ◽  
Myeloproliferative Neoplasms ◽  
Philadelphia Chromosome ◽  
Gene Mutations ◽  
Chronic Phase ◽  
Final Diagnosis ◽  
Jak2v617f Mutation ◽  
Myeloproliferative Disease

Abstract Background: The elucidation of the genetic background of the myeloproliferative neoplasms completely changed the management of these disorders: the presence of the Philadelphia chromosome and/or the BCR-ABL oncogene is pathognomonic for chronic myeloid leukemia and identification of JAK2 gene mutations are useful in polycytemia vera (PV), essential thrombocytemia (ET) and myelofibrosis (PMF). The aim of this study was to investigate the role of molecular biology tests in the management of myeloproliferative neoplasms. Materials and methods: We tested the blood samples of 117 patients between April 2008 and February 2013 at the Molecular Biology of UMF Târgu Mureș using RQ-PCR (for M-BCR-ABL oncogene) and/or allele-specific PCR (for JAK2V617F mutation). Results: Thirty-two patients presented the M-BCR-ABL oncogene, 16 of them were regularly tested as a follow-up of the administered therapy: the majority of chronic phase patients presented decreasing or stable values, while in case of accelerated phase and blast phase the M-BCR-ABL values increased or remained at the same level. Twenty patients were identified with the JAK2V617F mutation: 8 patients with PV, 4 with ET, 3 with PMF, 4 with unclassifiable chronic myeloproliferative disease and 1 patient with chronic myelomonocytic leukemia. There was no case of concomitant occurance of both molecular markers. Conclusions: Molecular biology testing plays an important role in the management of myeloproliferative neoplasms: identification of the molecular markers confirms the final diagnosis, excluding secondary causes of abnormal blood count parameters. Regular monitoring of MBCR- ABL expression level is useful in the follow-up of therapeutic efficiency.

Analysis of DNA methyltransferase 3A gene mutations in patients with Philadelphia-negative myeloproliferative neoplasms

2017 ◽  
Vol 6 (1) ◽  
pp. 81
Author(s):  
Najmaldin Saki ◽  
Neda Ketabchi ◽  
Mostafa Paridar ◽  
Javad Mohammadi-Asl ◽  
Alireza Abooali ◽  
...  
Keyword(s):  
Dna Methyltransferase ◽  
Myeloproliferative Neoplasms ◽  
Gene Mutations ◽  
Dna Methyltransferase 3A

scholarly journals EZH2 in Myeloid Malignancies

Cells ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1639 ◽  
Author(s):  
Jenny Rinke ◽  
Andrew Chase ◽  
Nicholas C. P. Cross ◽  
Andreas Hochhaus ◽  
Thomas Ernst
Keyword(s):  
Myeloid Leukemia ◽  
Kinase Inhibitor ◽  
Residual Disease ◽  
Myeloproliferative Neoplasms ◽  
Gene Mutations ◽  
Loss Of Function ◽  
Disease Pathogenesis ◽  
Catalytic Core ◽  
Myeloid Malignancies ◽  
Treatment Free Remission

Our understanding of the significance of epigenetic dysregulation in the pathogenesis of myeloid malignancies has greatly advanced in the past decade. Enhancer of Zeste Homolog 2 (EZH2) is the catalytic core component of the Polycomb Repressive Complex 2 (PRC2), which is responsible for gene silencing through trimethylation of H3K27. EZH2 dysregulation is highly tumorigenic and has been observed in various cancers, with EZH2 acting as an oncogene or a tumor-suppressor depending on cellular context. While loss-of-function mutations of EZH2 frequently affect patients with myelodysplastic/myeloproliferative neoplasms, myelodysplastic syndrome and myelofibrosis, cases of chronic myeloid leukemia (CML) seem to be largely characterized by EZH2 overexpression. A variety of other factors frequently aberrant in myeloid leukemia can affect PRC2 function and disease pathogenesis, including Additional Sex Combs Like 1 (ASXL1) and splicing gene mutations. As the genetic background of myeloid malignancies is largely heterogeneous, it is not surprising that EZH2 mutations act in conjunction with other aberrations. Since EZH2 mutations are considered to be early events in disease pathogenesis, they are of therapeutic interest to researchers, though targeting of EZH2 loss-of-function does present unique challenges. Preliminary research indicates that combined tyrosine kinase inhibitor (TKI) and EZH2 inhibitor therapy may provide a strategy to eliminate the residual disease burden in CML to allow patients to remain in treatment-free remission.

A Rare Combination of Genetic Mutations in an Elderly Female: A Diagnostic Dilemma!

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 5487-5487
Author(s):  
Prabhsimranjot Singh ◽  
Sudhamshi Toom ◽  
Makardhwaj S Shrivastava ◽  
William B. Solomon
Keyword(s):  
Polycythemia Vera ◽  
Myeloproliferative Neoplasms ◽  
Gene Mutations ◽  
Health Science ◽  
Receptor Protein ◽  
Hfe Gene ◽  
Science Center ◽  
C282y Mutation ◽  
Giant Platelets ◽  
Elderly Female

Introduction: JAK2 is located on chromosome 9p24 and includes 25 exons encoding a protein of about 1132 amino acids. JAK2 is one of the four Janus family non-receptor protein tyrosine kinases. JAK2V617F is by far the most prevalent mutation in BCR-ABL1-negative Myeloproliferative neoplasms (occurs in ∼95% of patients with polycythemia vera, in ∼55% with essential thrombocythemia and in ∼65% with primary myelofibrosis) 1, 2. More than 80% of hemochromatosis patients are homozygous for a C282Y mutation in HFE gene, and a smaller proportion are compound heterozygous for both the C282Y mutation and an H63D mutation3. Here we present the first case of an elderly female with concomitant diagnosis of Polycythemia Vera (PV) and hemochromatosis. To our knowledge, there is no literature about the co-existence or associations of these diseases. Case Reports: 75 year old female, former smoker with PMH of hemochromatosis and COPD with recent exacerbation, presented to the oncology clinic after hospital discharge for continuing care of her hemochromatosis requiring phlebotomy. She reports to have had multiple phlebotomies in the past fifteen years. Patient denied any history of liver disease, diabetes, arthralgia, skin pigmentation or sleep problems. Vital signs and examination were within normal limits. Her initial work up reported significantly elevated hemoglobin of 17.4gm/dl, hematocrit of 56.1%, RBC count of 6.98M/UL with MCV 80.4 fl, MCH 24.9 pg and platelet count of 673 K/UL. Peripheral smear showed normal red cell morphology and few giant platelets. Subsequently, further lab testing revealed ferritin of 25.7ng/ml. Her elevated hematocrit was further evaluated and erythropoietin was surprisingly <1mIU/ml. Genetic testing for HFE gene mutation screen was positive for homozygous C282Y mutation. Due to high suspicion for Polycythemia Vera, JAK2 mutation was also tested, which to our surprise, came back positive for JAK2 V617F point mutation. Patient is diagnosed with Polycythemia Vera and Hereditary Hemochromatosis and is recommended to start Aspirin, continue phlebotomy to maintain Hematocrit below 45% and take hydroxyurea for thrombocytosis. Discussion: It is interesting to note the co-existence of two un-related diseases. Franchini M et al analyzed 52 patients with PV for 12 HH gene mutations and found no significant association between the two conditions4. Hannuksela J et al studied C282Y and H63D mutations in 232 patients with hematological malignancies and reported no significant association5. Beaton and Adams in their review article about the myths and realities of hemochromatosis reports an elevated hemoglobin, in hemochromatosis's patient as a myth, based on their review of 634 C282Y homozygous patients at London health Science center, with mean hemoglobin of 145±13 g/L6. Our case re-iterates the importance of clinical suspicion of polycythemia Vera in a hemochromatosis patient with elevated hematocrit and undetectable erythropoietin. The coincidence is, phlebotomy is the treatment for both conditions as long as patient is fairly asymptomatic. References: 1. Ayalew Tefferi; Molecular drug targets in myeloproliferative neoplasms: mutant ABL1, JAK2, MPL, KIT, PDGFRA, PDGFRB and FGFR1; J Cell Mol Med. 2009 Feb; 13(2): 215-237. 2. Cross NC (2011); Genetic and epigenetic complexity in myeloproliferative neoplasms. Hematology Am Soc Hematol Educ Program 2011:208-214. 3. Feder JN, Gnirke A, Thomas W, et al. A novel MHC class I-like gene is mutated in patients with hereditary haemochromatosis. Nat Genet1996; 13:399-408. 4. Analysis of hemochromatosis gene mutations in 52 consecutive patients with polycythemia vera. Franchini M1, de Matteis G, Federici F, Solero P, Veneri D. Hematology. 2004 Oct-Dec;9(5-6):413-4. 5. Prevalence of HFE genotypes, C282Y and H63D, in patients with hematologic disorders. Hannuksela J, Savolainen ER, Koistinen P, Parkkila S. Haematologica. 2002 Feb;87(2):131-5. 6. The myths and realities of hemochromatosis Melanie D Beaton, Paul C Adams Can J Gastroenterol. 2007 February; 21(2): 101-104. PMCID: PMC2657669 Disclosures No relevant conflicts of interest to declare.

scholarly journals Impact of gene mutations on treatment response and prognosis of acute myeloid leukemia secondary to myeloproliferative neoplasms

2017 ◽  
Vol 93 (3) ◽  
pp. 330-338 ◽  
Author(s):  
Geoffroy Venton ◽  
Frédéric Courtier ◽  
Aude Charbonnier ◽  
Evelyne D'incan ◽  
Colombe Saillard ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Treatment Response ◽  
Myeloid Leukemia ◽  
Myeloproliferative Neoplasms ◽  
Gene Mutations ◽  
Acute Myeloid

scholarly journals Calreticulin – a multifaced protein

2021 ◽  
Vol 75 ◽  
pp. 328-336
Author(s):  
Zuzanna Kanduła ◽  
Krzysztof Lewandowski
Keyword(s):  
Cell Surface ◽  
Antigen Processing ◽  
Myeloproliferative Neoplasms ◽  
Rna Stability ◽  
Adaptive Immune Response ◽  
Gene Mutations ◽  
T Cell Response ◽  
Cell Surface Expression ◽  
Hematopoietic Stem ◽  
Exon 9

Calreticulin (CALR) is a highly conserved multi-function protein that primarily localizes within the lumen of the endoplasmic reticulum (ER). It participates in various processes in the cells, including glycoprotein chaperoning, regulation of Ca2+ homeostasis, antigen processing and presentation for adaptive immune response, cell adhesion/migration, cell proliferation, immunogenic cell death, gene expression and RNA stability. The role of CALR in the assembly, retrieval and cell surface expression of MHC class I molecules is well known. A fraction of the total cellular CALR is localized in the cytosol, following its retro-translocation from the ER. In the cell stress conditions, CALR is also expressed on the cell surface via an interaction with phosphatidylserine localized on the inner leaflet of the plasma membrane. The abovementioned mechanism is relevant for the recognition of the cells, as well as immunogenicity and phagocytic uptake of proapoptotic and apoptotic cells. Lastly, the presence of CALR exon 9 gene mutations was confirmed in patients with myeloproliferative neoplasms. Their presence results in an abnormal CALR structure due to the loss of its ER-retention sequence, CALR extra-ER localisation, the formation of a complex with thrombopoietin receptor, and oncogenic transformation of hematopoietic stem cells. It is also known that CALR exon 9 mutants are highly immunogenic and induce T cell response. Despite this fact, CALR mutant positive hematopoietic cells emerge. The last phenomenon is probably the result of the inhibition of phagocytosis of the cancer cells exposing CALR mutant protein by dendritic cells.

scholarly journals Predisposition to Myeloproliferative Neoplasms

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. SCI-33-SCI-33
Author(s):  
Radek C. Skoda
Keyword(s):  
Germline Mutation ◽  
Myeloproliferative Neoplasms ◽  
Single Gene ◽  
Adult Life ◽  
Gene Mutations ◽  
Germline Mutations ◽  
Erythropoietin Receptor ◽  
Driver Mutations ◽  
Disease Manifestation

Familial forms of myeloproliferative neoplasms (MPN) and genetic contribution to sporadic cases of MPN have long been recognized. In the majority of cases, familial MPN is inherited as an autosomal dominant trait. The penetrance varies from around 20% to up to 100% in some pedigrees. We can distinguish two types of familial MPN. Type 1 has high penetrance, polyclonal hematopoiesis and hyperproliferation of a single hematopoietic lineage, caused by mutations in a single gene and usually manifesting at birth or early childhood. Examples are mutations in the genes for the erythropoietin receptor, thrombopoietin or its receptor, MPL. The type 2 familial MPNs are characterized by clonal hematopoiesis, low penetrance and manifestation beginning in most cases later in adult life. These type 2 familial MPNs are classical examples of inherited predisposition to a clonal malignant disease, in which acquired somatic mutations in hematopoietic cells are required for disease manifestation. Affected family members typically display the same acquired driver mutations in the genes for JAK2 (JAK2-V617F or JAK2-exon12), MPL (MPL-W515), or calreticulin (CALR) as patients with sporadic MPN. The mutated genes and the mechanism of how these inherited germline mutations predispose to MPN have not yet been elucidated. The search for these germline mutations has been hampered by the low penetrance of MPN manifestation and the rare occurrence of pedigrees that are large enough for genetic studies. Furthermore, the few candidate gene mutations that have been identified to date do not map to one gene locus and the function of the candidate genes does not fall into a common category. Two models of how the germline predisposition interacts with acquired driver mutations can be considered. First, the germline mutation may increase the mutation rate for gene mutations in JAK2, MPL, and CALR. Second, the germline mutation functionally synergizes with mutations in JAK2, MPL, and CALR and promotes disease initiation. The current state of our studies and studies in other laboratories will be discussed. Disclosures Skoda: Novartis: Consultancy; Sanofi: Consultancy.

Comprehensive Molecular Analyses of BCR-ABL1 Negative MPN Show That PMF Is Genetically Much More Heterogeneous Than ET and PV

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3224-3224
Author(s):  
Manja Meggendorfer ◽  
Tamara Alpermann ◽  
Claudia Haferlach ◽  
Wolfgang Kern ◽  
Susanne Schnittger ◽  
...  
Keyword(s):  
Myeloproliferative Neoplasms ◽  
Gene Mutations ◽  
Normal Karyotype ◽  
Great Majority ◽  
Primary Myelofibrosis ◽  
Gene Panel ◽  
Prognostic Impact ◽  
Prognostic Information ◽  
Employment Equity ◽  
Equity Ownership

Abstract Introduction: In the WHO classification (2008) JAK2 and MPL mutations are major criteria for the diagnosis of myeloproliferative neoplasms (MPN): polycythemia vera (PV), primary myelofibrosis (PMF), and essential thrombocythemia (ET). Cytogenetic aberrations are rare in these entities. Although the prognostic impact of JAK2 mutations beside some other gene mutations has been shown in PMF patients, the driving events for establishing accelerated phase or blast crises are unknown. In recent years, novel molecular markers such as ASXL1, SRSF2, and CALR were identified and PMF was investigated in several studies. However, comprehensive mutational analyses of MPN entities in comparison to each other are still rare. Aim: To identify gene mutations beyond JAK2, CALR, and MPL using a 28 gene panel, and to compare mutational data with clinical data and prognostic information in order to identify a risk profile. Patients and Methods: We in the first step investigated 56 patients (19 ET, 18 PMF, and 19 PV; 21 females, 35 males) diagnosed by cytomorphology following WHO criteria and accompanied by genetic studies. All patients underwent mutation analyses by a 28 gene panel containing: ASXL1, BCOR, BRAF, CALR, CBL, DNMT3A, ETV6, EZH2, FLT3-TKD, GATA1, GATA2, IDH1, IDH2, JAK2, KIT, NRAS, KRAS, MPL, NPM1, PHF6, RUNX1, SETBP1, SF3B1, SRSF2, TET2, TP53, U2AF1, and WT1. The library was generated with the ThunderStorm (RainDance Technologies, Billerica, MA) and sequenced on MiSeq instruments (Illumina, San Diego, CA). BCR-ABL1 fusion transcripts were shown to be negative in all cases by PCR. Not yet described genetic variants (n=6) were excluded from statistical analyses. Cytogenetics was available in 55/56 cases and grouped in normal karyotype (n=45, 82%) or aberrant karyotype (n=10, 18%). Results: In the total cohort JAK2 (44/56, 79%) was the most frequently mutated gene, followed by TET2 (13/56, 23%), ASXL1 (11/56, 20%), SRSF2 (7/56, 13%), and CALR (6/56, 11%). All other analyzed genes showed mutation frequencies below 10% (10 genes) or even no mutation (13 genes). Analyzing the number of mutations per patient revealed that only 4 patients showed no mutation (4/56, 7%), the great majority had 1 mutation (19/56, 34%) and 2 mutations (23/56, 41%), while 5 patients showed 3 mutations (5/56, 9%), 4 patients had 4 (4/56, 7%) and 1 patient even 5 mutations (1/56, 2%). Accordingly, the mean number of mutations per patient was 1.9. Summing up the mutations in JAK2, CALR, and MPL resulted in 52/56 (93%) patients that had a mutation in at least 1 of these genes, indicating that most of the patients had just 1 or 2 additional gene mutations to one of the 3 known key player MPN genes (mean: 1.3 additional mutations). Cytogenetically there were no significant differences between the 3 entities in frequencies of normal (65-90%) and aberrant karyotypes (11-35%), although in the PMF cohort there were more aberrant karyotypes (6/17, 35%) in comparison to ET and PV (for each 2/19, 11%). Addressing the mutation patterns of these 3 MPN entities revealed similar frequencies of TET2 mutations. In contrast, as expected JAK2 was more often mutated in PV (18/19, 95%) compared to ET (12/19, 63%, p=0.042) and PMF (14/18, 78%) and CALR was more often mutated in ET (5/19, 26%) in comparison to PMF (1/18, 6%) and PV (0/19, 0%, p=0.046). In PMF ASXL1 (8/18, 44%) and SRSF2 (6/18, 33%) were more often mutated compared to ET (1/19, 5%, p=0.008; 1/19, 5%, p=0.042) and PV (2/19, 11%; p=0.029; 0/19, 0%; p=0.008), respectively. Investigating the numbers of mutated genes per patient resulted in a significantly different distribution within MPN entities: in the ET and PV cohorts patients carried mostly 1 or 2 mutations (36/38, 95%; mean: 1.5), while in PMF 9/18 (50%) patients carried >2 mutations (mean: 2.5; p=0.045). Looking at the affected genes besides JAK2 and CALR showed that in ET and PV 4 more genes were affected, while in PMF 11 different additional genes showed mutations, indicating that PMF is genetically much more heterogeneous than ET or PV. This nicely matches to the finding that PMF is also marked by the highest cytogenetic aberration rate of these 3 BCR-ABL1 negative MPN (24-42%). Conclusions: 1)JAK2 is the most and TET2 the second most frequently mutated gene in BCR-ABL1 negative MPN. 2) Most patients carry only 1 or 2 gene mutations. 3) However, PMF patients are genetically much more heterogeneous than ET and PV patients regarding both cytogenetic and molecular alterations. Disclosures Meggendorfer: MLL Munich Leukemia Laboratory: Employment; Novartis: Research Funding. Alpermann:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Calr Gene Mutation in Patients with JAK2-Negative Myeloproliferative Neoplasms

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 5190-5190
Author(s):  
Xu Jingyan ◽  
Rong-Fu Zhou ◽  
Bing Chen ◽  
Jian Ouyang
Keyword(s):  
Mutation Rate ◽  
Conflicts Of Interest ◽  
Novel Mutation ◽  
Myeloproliferative Neoplasms ◽  
Direct Sequencing ◽  
Gene Mutations ◽  
Jak2v617f Mutation ◽  
Positive Rate ◽  
Exon 9 ◽  
Calr Mutation

Abstract Methods Genomic DNA from bone marrow and peripheral blood cells were extracted from 40 patients with MPD(male 26,female 14),Aged 13 to 76 years old, JAK2V617F mutation and CALR genetic mutations was identified by PCR- direct sequencing. Results The number of MPD(PV15,ET25) 40 cases in patients with JAK2V617F mutation rate was 60%,among them the polycythemia vera ( PV) positive rate was 66. 7% ( 10 /15) ,and essential thrombocythemia ( ET ) positive rate was 56% ( 14 /25) . The number of JAK2V617F -negative MPD 16 cases in patients with CALR mutation rate was 12. 5% ( 2 /16),Two of the 11 patients with ET were CALR mutation positive(18.2%). Two novel mutation in CALR exon 9,c.1099_1150del ( p. chr19F12915572-12915623del) was detected in patient Tao c.1099-1151delinsT( p.chr19:12915572_12915624delinsT) was detected in patient Xu. These mutation was absent in the controls,Two novel mutation in CALR have not been reported so far. Conclusion CALR gene mutations testing helps to JAK2V617F negative MPD diagnosis, makes the MPD early detection and treatment. Disclosures No relevant conflicts of interest to declare.

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