Association of loss of heterozygosity with cytogenetic abnormalities in acute myeloid leukemia and myelodysplastic syndrome

Deletions on chromosomes 5 and 7 are frequently seen in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). It is assumed that these deletions indicate loss of tumor suppressor genes on these chromosomes and until these tumor suppressor genes are identified, the functional consequences of these deletions and the molecular basis of these myeloid disorders cannot be completely understood. We evaluated loss of heterozygosity (LOH) in 44 patients (18 MDS and 26 AML, diagnosed according to WHO classification criteria) at diagnosis, using a four-microsatellite marker panel: an intragenic marker on the 7th intron of gene IRF-1 of the 5q31.1 region and three markers located inside the 7q31.1 region and correlated the LOH with karyotype abnormalities. The microsatellites chosen corresponded to chromosome regions frequently deleted in MDS/AML. The samples with Q (peak area) less than or equal to 0.50 were indicative of LOH. The percent of informative samples (i.e., heterozygous) for the intragenic microsatellite in gene IRF-1 and in loci D7S486, D7S515 and D7S522 were 66.6, 73.7, 75.5, and 48.8%, respectively. Cytogenetic abnormalities by G-banding were found in 36% (16/44) of the patients (2 of 18 MDS and 14 of 26 AML patients). We found a significantly positive association of the occurrence of LOH with abnormal karyotype (P < 0.05; chi-square test) and there were cases with LOH but the karyotype was normal (by G-banding). These data indicate that LOH in different microsatellite markers is possibly an event previous to chromosomal abnormalities in these myeloid neoplasias

Acute promyelocytic leukemia: the study of t(15;17) translocation by fluorescent in situ hybridization, reverse transcriptase-polymerase chain reaction and cytogenetic techniques

Acute promyelocytic leukemia (AML M3) is a well-defined subtype of leukemia with specific and peculiar characteristics. Immediate identification of t(15;17) or the PML/RARA gene rearrangement is fundamental for treatment. The objective of the present study was to compare fluorescent in situ hybridization (FISH), reverse transcriptase-polymerase chain reaction (RT-PCR) and karyotyping in 18 samples (12 at diagnosis and 6 after treatment) from 13 AML M3 patients. Bone marrow samples were submitted to karyotype G-banding, FISH and RT-PCR. At diagnosis, cytogenetics was successful in 10 of 12 samples, 8 with t(15;17) and 2 without. FISH was positive in 11/12 cases (one had no cells for analysis) and positivity varied from 25 to 93% (mean: 56%). RT-PCR was done in 6/12 cases and all were positive. Four of 8 patients with t(15;17) presented positive RT-PCR as well as 2 without metaphases. The lack of RT-PCR results in the other samples was due to poor quality RNA. When the three tests were compared at diagnosis, karyotyping presented the translocation in 80% of the tested samples while FISH and RT-PCR showed the PML/RARA rearrangement in 100% of them. Of 6 samples evaluated after treatment, 3 showed a normal karyotype, 1 persistence of an abnormal clone and 2 no metaphases. FISH was negative in 4 samples studied and 2 had no material for analysis. RT-PCR was positive in 4 (2 of which showed negative FISH, indicating residual disease) and negative in 2. When the three tests were compared after treatment, they showed concordance in 2 of 6 samples or, when there were not enough cells for all tests, concordance between karyotype and RT-PCR in one. At remission, RT-PCR was the most sensitive test in detecting residual disease, as expected (positive in 4/6 samples). An incidence of about 40% of 5' breaks and 60% of 3' breaks, i.e., bcr3 and bcr1/bcr2, respectively, was observed

Philadelphia-negative Chronic Myeloproliferative Neoplasms

Chronic myeloproliferative diseases without the Philadelphia chromosome marker (Ph-), although first described 60 years ago, only became the subject of interest after the turn of the millennium. In 2001, the World Health Organization (WHO) defined the classification of this group of diseases and in 2008 they were renamed myeloproliferative neoplasms based on morphological, cytogenetic and molecular features. In 2005, the identification of a recurrent molecular abnormality characterized by a gain of function with a mutation in the gene encoding Janus kinase 2 (JAK2) paved the way for greater knowledge of the pathophysiology of myeloproliferative neoplasms. The JAK2 mutation is found in 90-98% of polycythemia vera and in about 50% essential thrombocytosis and primary myelofibrosis. In addition to the JAK2 mutation, other mutations involving TET2 (ten-eleven translocation), LNK (a membrane-bound adaptor protein); IDH1/2 (isocitrate dehydrogenase 1/2 enzyme); ASXL1 (additional sex combs-like 1) genes were found in myeloproliferative neoplasms thus showing the importance of identifying molecular genetic alterations to confirm diagnosis, guide treatment and improve our understanding of the biology of these diseases. Currently, polycythemia vera, essential thrombocytosis, myelofibrosis, chronic neutrophilic leukemia, chronic eosinophilic leukemia and mastocytosis are included in this group of myeloproliferative neoplasms, but are considered different situations with individualized diagnostic methods and treatment. This review updates pathogenic aspects, molecular genetic alterations, the fundamental criteria for diagnosis and the best approach for each of these entities.342140149Tefferi, A., Vainchenker, W., Myeloproliferative neoplasms: Molecular pathophysiology, essential clinical understanding, and treatment strategies (2011) J Clin Oncol., 29 (5), pp. 573-582. , Comment in: J Clin Oncol. 2011;29(18):e564-5Laszlo, J., Myeloproliferative disorders (MPD): Myelofibrosis, myeloscrerosis, extramedullary hematopoiesis, undifferentiated MPD, and hemorrhagic thrombocythemia (1975) Semin Hematol., 12 (4), pp. 409-432Vardiman, J.W., Harris, N.L., Brunning, R., The World Health Organization (WHO) classification of the myeloid neoplasms (2002) Blood., 100 (7), pp. 2292-2302. , Comment in: Blood. 2003;101(7):2895-6Tefferi, A., Vardiman, J.W., Classification and diagnosis of myeloproliferative neoplasms: The 2008 World Health Organization criteria and point-of-care diagnostic algorithms (2008) Leukemia., 22 (1), pp. 14-22. , Comment in: Leukemia. 2008;22(11):2118-9Vardiman, J.W., Thiele, J., Arber, D.A., Brunning, R.D., Borowitz, M.J., Porwit, A., The 2008 revision of the World Health Organization (WHO) classification of myeloid neoplasms and acute leukemia: Rationale and important changes (2009) Blood, 114 (5), pp. 937-951. , Comment in: Blood. 2010;115(3):748-9author reply 749-50Thiele, J., Kvasnicka, H.M., Facchetti, F., Franco, V., van der Walt, J., Orazi, A., European consensus on grading bone marrow fibrosis and assessment of cellularity (2005) Haematologica., 90 (8), pp. 1128-1132Thiele, J., Kvasnicka, H.M., Diehl, V., Standardization of bone marrow features-does it work in hematopathology for histological discrimination of different disease patterns? (2005) Histol Histopathol., 20 (2), pp. 633-644Thiele, J., Kvasnicka, H.M., The 2008 WHO diagnostic criteria for polycythemia vera, essential thrombocythemia and primary myelofibrosis (2009) Curr Hematol Malig Rep., 4 (1), pp. 33-40Ahmed, A., Chang, C.C., Chronic idiopathic myelofibrosis: Clinicopathologic features, pathogenesis and prognosis (2006) Arch Pathol Lab Med., 130 (8), pp. 1133-1143Chauffaille, M.L., Neoplasias mieloproliferativas: Revisão dos critérios diagnósticos e dos aspectos clínicos (2010) Rev Bras Hematol Hemoter., 32 (4), pp. 308-316Maciel, J.F., de Lourdes Chauffaille, M., Inaoka, R.J., Colleoni, G.W., Yamamoto, M., Essential Thrombocythemia after treatment of non-Hodgkin's Lymphoma (2007) Leuk Res., 31 (11), pp. 1593-1595Gangat, N., Tefferi, A., Thanarajasingam, G., Patnaik, M., Schwager, S., Ketterling, R., Cytogenetic abnormalities in essential thrombocythemia: Prevalence and prognostic significance (2009) Eur J Haematol., 83 (1), pp. 17-21Baxter, E.J., Scott, L.M., Campbell, P.J., East, C., Fourouclas, N., Swanton, S., Vassiliou, G.S., Green, A.R., Acquired mutation of the tyrosine kinase JAK2 in human myeloproliferative disorders (2005) Lancet., 365 (9464), pp. 1054-1061. , Cancer Genome Project. Erratum in: Lancet. 2005;366(9480):122Levine, R.L., Pardanani, A., Tefferi, A., Gilliland, D.G., Role of JAK2 in the pathogenesis and therapy of myeloproliferative disorders (2007) Nat Rev Cancer., 7 (9), pp. 673-683Barosi, G., Bergamaschi, G., Marchetti, M., Vannucchi, A.M., Guglielmelli, P., Antonioli, E., Massa, M., Barbui, T., JAK2 V617F mutational status predicts progression to large splenomegaly and leukemic transformation in primary myelofibrosis (2007) Blood., 110 (12), pp. 4030-4036. , Gruppo Italiano Malattie Ematologiche Maligne dell'Adulto (GIMEMA) Italian Registry of MyelofibrosisKantarjian, H., Schiffer, C., Jones, D., Cortes, J., Monitoring the response and course of chronic myeloid leukemia in the modern era of BCR-ABL tyrosine kinase inhibitors: Practical advice on use and interpretation of monitoring methods (2008) Blood, 111 (4), pp. 1774-1780Guglielmelli, P., Barosi, G., Specchia, G., Rambaldi, A., Lo Coco, F., Antonioli, E., Identification of patients with poorer survival in primary myelofibrosis based on the burden of JAK2V617F mutated allele (2009) Blood, 114 (8), pp. 1477-1483Tefferi, A., Lasho, T.L., Huang, J., Finke, C., Hanson, C.A., Mesa, R.A., Low JAK2V617F allele burden in primary myelofibrosis, compared to either a higher allele burden or unmutated status, is associated with inferior overall and leukemia-free survival (2008) Leukemia., 22 (4), pp. 756-761Tefferi, A., Novel mutations and their functional and clinical relevance in myeloproliferative neoplasms: JAK2, MPL, TET2, ASXL1, CBL, IDH and IKZF1 (2010) Leukemia., 24 (6), pp. 1128-1138Tefferi, A., Thiele, J., Orazi, A., Kvasnicka, H.M., Barbui, T., Hanson, C.A., Proposals and rationale for revision of the World Health Organization diagnostic criteria for polycythemia vera, essential thrombocythemia, and primary myelofibrosis: Recommendations from an ad hoc international expert panel (2007) Blood., 110 (4), pp. 1092-1097. , Comment in: Blood. 2008;111(3): 1741author reply 1742Johansson, P., Epidemiology of the myeloproliferative disorders polycythemia vera and essential thrombocythemia (2006) Semin Thromb Hematost, 32 (3), pp. 171-173Giuglielmelli, P., Tefferi, A., Advances in understanding and management of myeloproliferative neoplasms (2009) CA Cancer J Clin., 59 (3), pp. 171-191Girodon, F., Bonicelli, G., Schaffer, C., Mounier, M., Carillo, S., Lafon, I., Significant increase in the apparent incidence of essential thrombocythemia related to new WHO diagnostic criteria: A population-based study (2009) Haematologica., 94 (6), pp. 865-869Harrison, C.N., Bareford, D., Butt, N., Campbel, P., Conneally, E., Drummond, M., Erber, W., Everington, T., Guideline for investigation and management of adults and children presenting with a thrombocytosis (2010) Br J Haematol., pp. 352-375Lussana, F., Caberlon, S., Pagani, C., Kamphuisen, P.W., Buller, H.R., Cattaneo, M., Association of V617F Jak2 mutation with the risk of thrombosis among patients with essential thrombocythaemia or idiopathic myelofibrosis: A systematic review (2009) Thromb Res., 124 (4), pp. 409-417Biergegard, G., Long-term management of thombocytosis in essential thrombocythaemia (2009) Ann Hematol., 88 (1), pp. 1-10Landolfi, R., Gennaro, L., Prevention of thrombosis in polycythemia vera and essential thrombocythemia (2008) Haematologica., 93 (3), pp. 331-335. , Comment on: Haematologica. 2008;93(3):372-80Finazzi, G., Ruggeri, M., Rodeghiero, F., Barbui, T., Efficacy and safety of long-term use of hydroxyurea in young patients with essential thrombocythemia and a high risk of thrombosis (2003) Blood., 101 (9), p. 3749. , Comment on: Blood. 2001;97(4):863-6Beer, P., Erber, W., Campbell, P., Green, A., How I treat essential thrombocythemia (2011) Blood., 117 (5), pp. 1472-1482. , Comment in: Blood. 2011;118(4):1179-80author reply 1180-1Kerbauy, D.M., Gooley, T.A., Sale, G.E., Flowers, M.E., Doney, K.C., Georges, G.E., Hematopoietic cell transplantation as curative therapy for idiopathic myelofibrosis, advanced polycythemia vera, and essential thrombocythemia. (2007) Biol Blood Marrow Transplant., 13 (3), pp. 355-365Spivak, J., Narrative review: Thrombocytosis, polycythemia vera, and JAK2 mutations: The phenotypic mimicry of chronic myeloproliferation (2010) Ann Intern Med., 152 (5), pp. 300-306Swerdlow, S.H., (2008) WHO classification of tumours of haematopoietic and lymphoid tissues, , International Agency for Research on Cancer., World Health Organization., Louis A. Duhring Fund. 4th ed. Lyon, France: International Agency for Research on CancerTefferi, A., Vaidya, R., Caramazza, D., Finke, C., Lasho, T., Pardanani, A., Circulating interleukin (IL)-8, IL-2R, IL-12, and IL-15 levels are independently prognostic in primary myelofibrosis: A comprehensive cytokine profiling study (2011) J Clin Oncol., 29 (10), pp. 1356-1363Barosi, G., Mesa, R.A., Thiele, J., Cervantes, F., Campbell, P.J., Verstovsek, S., Dupriez, B., Tefferi, A., Proposed criteria for the diagnosis of post-polycythemia vera and post-essential thrombocythemia myelofibrosis: A consensus statement from the International Working Group for Myelofibrosis Research and Treatment (2008) Leukemia., 22 (2), pp. 437-438. , International Working Group for Myelofibrosis Research and Treatment (IWG-MRT)Cervantes, F., Dupriez, B., Pereira, A., Passamonti, F., Reilly, J.T., Morra, E., Vannucchi, A.M., New prognostic scoring system for primary myelofibrosis based on a study of the International Working Group for Myelofibrosis Research and Treatment (2009) Blood, 113 (13), pp. 2895-2901. , Comment in: Blood. 2010;115(3):745author reply 745-6Passamonti, F., Cervantes, F., Vannucchi, A.M., Morra, E., Rumi, E., Cazzola, M., Dynamic International Prognostic Scoring System (DIPSS) predicts progression to acute myeloid leukemia in primary myelofibrosis (2010) Blood., 116 (15), pp. 2857-2858Tefferi, A., Siragusa, S., Hussein, K., Schwager, S.M., Hanson, C.A., Pardanani, A., Transfusion-dependency at presentation and its acquisition in the first year of diagnosis are both equally detrimental for survival in primary myelofibrosis--prognostic relevance is independent of IPSS or karyotype (2010) Am J Hematol., 85 (1), pp. 14-17. , Comment in: Am J Hematol. 2010;85(1):4-5Caramazza, D., Begna, K.H., Gangat, N., Vaidya, R., Siragusa, S., van Dyke, D.L., Refined cytogenetic-risk categorization for overall and leukemia-free survival in primary myelofibrosis: A single center study of 433 patients (2011) Leukemia., 25 (1), pp. 82-88Mesa, R.A., Nagorney, D.S., Schwager, S., Allred, J., Tefferi, A., Palliative goals, patient selection, and perioperative platelet management: Outcomes and lessons from 3 decades of splenectomy for myelofibrosis with myeloid metaplasia at the Mayo Clinic (2006) Cancer., 107 (2), pp. 361-370Elliott, M.A., Tefferi, A., Splenic irradiation in myelofibrosis with myeloid metaplasia: A review (1999) Blood Rev., 13 (3), pp. 163-170Ballen, K.K., Shrestha, S., Sobocinski, K.A., Zhang, M.J., Bashey, A., Bolwell, B.J., Outcome of transplantation for myelofibrosis (2010) Biol Blood Marrow Transplant., 16 (3), pp. 358-367Verstovsek, S., Kantarjian, H., Mesa, R.A., Pardanani, A.D., Cortes-Franco, J., Thomas, D.A., Safety and efficacy of INCB018424, a JAK1 and JAK2 inhibitor, in myelofibrosis (2010) N Engl J Med., 363 (12), pp. 1117-1127. , Comment in: N Engl J Med. 2010363(12): 1180-2N Engl J Med. 2010;363(25):2464author reply 2464-5discussion 2465Pardanani, A., Gotlib, J.R., Jamieson, C., Cortes, J.E., Talpaz, M., Stone, R.M., Safety and efficacy of TG101348, a selective JAK2 inhibitor, in myelofibrosis (2011) J Clin Oncol., 29 (7), pp. 789-796. , J Clin Oncol. 2011;29(7):781-3Vaquez, H., Sur une forme spéciale de cyanose s'accompgnant d'hyperglobulie excessive et persistant (1892) Comptes rendus de La Société de Biologie, 44, pp. 384-388. , ParisOsler, W., Chronic cyanosis with polycythemia and enlarged spleen: A new clinical entity (2008) Am J Med Sci., 335 (6), pp. 411-417. , Comment in: Am J Med Sci 2008;335(6):418-9Berlin, N.I., Diagnosis and classification of the polycythemias (1975) Semin Hematol., 12 (4), pp. 339-351Kralovics, R., Passamonti, F., Buser, A.S., Teo, S.S., Tiedt, R., Passweg, J.R., A gain-of-function mutation of JAK2 in myeloproliferative disorders (2005) N Engl J Med., 352 (17), pp. 1779-1790. , Comment in: N Engl J Med. 2005;353(13):1416-7author reply 1416-7N Engl J Med. 2005;352(17):1744-6Passamonti, F., Rumi, E., Pietra, D., della Porta, M.G., Boveri, E., Pascutto, C., Relation between JAK2(V617F) mutation status, granulocyte activation and constitutive mobilization of CD34+ cells into peripheral blood in myeloproliferative disorders (2006) Blood., 107 (9), pp. 3676-3682Scott, L.M., Tong, W., Levine, R.L., Scott, M.A., Beer, P.A., Stratton, M.R., JAK2 exon 12 mutations in polycythemia vera and idiopathic eritrocytosis (2007) N Engl J Med., 356 (5), pp. 459-468. , Comment in: N Engl J Med. 2007;356(5):444-5McMullin, M., Reilly, J.T., Campbell, P., Bareford, D., Green, A., Harrison, C., Amendment to the guideline for diagnosis and investigation of polycythaemia/erythrocytosis (2007) Br J Haematol, 138, pp. 812-823Crisà, E., Venturino, E., Passera, R., Prina, M., Schinco, P., Borchiellini, A., A retrospective study on 226 polycythemia vera patients: Impact of median hematocrit value on clinical outcomes and survival improvement with anti-thrombotic prophylaxis and nonalkylating drugs (2010) Ann Hematol., 89 (7), pp. 691-699Barbui, T., Carobbio, A., Rambaldi, A., Finazzi, G., Perspectives on thrombosis in essential thrombocythemia and polycythemia vera: Is leukocytosis a causative factor? (2009) Blood., 114 (4), pp. 759-763Barosi, G., Birgegard, G., Finazzi, G., Griesshammer, M., Harrison, C., Hasselbalch, H.C., Response criteria for essential thrombocythemia and polycythemia vera: Result of a European LeukemiaNet consensus conference (2009) Blood., 113 (20), pp. 4829-4833Barbui, T., Barosi, G., Birgegard, G., Cervantes, F., Finazzi, G., Griesshammer, M., Harrison, C., Tefferi, A., Philadelphia-Negative Classical Myeloproliferative Neoplass: Critical Concepts and Management Recommendations from European Leukemianet (2011) J Clin Oncol., 29 (6), pp. 761-770. , European LeukemiaNet. Comment in: J Clin Oncol. 2011;29(18):e564-5Rambaldi, A., Dellacasa, C.M., Salmoiraghi, S., A phase 2 A study of the histone-deacetylase inhibitor in patients with JAK2V617F positive myeloproliferative neoplasms. {abstract} (2008) Blood, 112, p. 100. , (não localizada)Chauffaille, M.L.L.F., Neoplasias mieloproliferativas: Revisão dos critérios diagnósticos e dos aspectos clínicos (2010) Rev Bras Hematol. Hemoter, 32 (4), pp. 308-316Tefferi, A., Patnaik, M.M., Pardanani, A., Eosinophilia: Secondary, clonal and idiopatic (2006) Br J Haematol., 133 (5), pp. 468-492Fletcher, S., Bain, B., Diagnosis and treatment of hypereosinophilic syndromes (2007) Curr Opin Hematol., 14 (1), pp. 37-42Metcalfe, D.D., Mast cells and mastocytosis (2008) Blood., 112 (4), pp. 946-95