Myeloproliferative neoplasms include a heterogeneous group of stem cell disorders with overproduction of myeloid cells. They have very different clinical courses and prognosis and are amenable to specific targeted therapy. A prompt and accurate diagnosis is therefore very important. Genetic characterisation plays an important role in diagnosis and classification of these disorders. BCR-ABL1fusion gene and JAK2V617F mutation are the particular major molecular markers to be detected because of availability of targeted therapy. In this study, a new molecular testing system was developed for the differential diagnosis of myeloproliferative neoplasms. A multiplex reverse-transcriptase polymerase chain reaction was developed for fast detection of JAK2 V617F mutation and BCR-ABL1fusion simultaneously. It was demonstrated to be fast and highly sensitive and specific for the mutations as validated by analysis of clinical samples. The sensitivity limit was well suited for clinical diagnosis. There was great potential saving in consumables and manpower with a much shortened turn-around-time in most cases when compared to conventional diagnostic protocol. / published_or_final_version / Pathology / Master / Master of Medical Sciences

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

Thesis (M. Med. Sc.)--University of Hong Kong, 2008. / Includes bibliographical references (p. 61-65)

Diss. (sammanfattning) Göteborg : Univ. , 2009. / Härtill 2 uppsatser.

I have been interested in the molecular mechanisms of Haematopoietic malignant diseases such as leukaemia and lymphoma, especially those involving oncogenic tyrosine kinases. About 30 of the 90 tyrosine kinases in the human genome have been implicated in cancer (Blume-Jensen P, 2001). The oncogenic tyrosine kinases (OTKs), such as Bcr-Abl (product of chromosomal translocations of two genes bcr and abl) in Chronic Myelogenous Leukaemia, and Erythroblastic leukaemia viral oncogene homolog 2(Erb-B2) in mammary and other cancers, mediate their transforming effects via a diverse array of signalling pathways involved in DNA damage, cell survival and cell cycle regulation (Deutsch E, 2001; Skorski T, 2002; Kumar R, 1996). My work has been centred around the analysis of a mouse cancer model that is driven by an oncogenic tyrosine kinase – p56 Lck-F505 expressed on CD45 knock- out background (Baker M, 2000). The investigation of this mouse model has revealed that oncogenic inhibition of deamidation of the Bcl-xL survival protein plays a critical role in protecting thymocytes from DNA-damage induced apoptosis. Cells that would normally be eliminated due to accumulating DNA damage are instead preserved with an increasing load of double-stranded breaks, leading to genomic instability, chromosomal abnormalities and transformation. This work was published in Cancer Cell (An oncogenic tyrosine kinase inhibits DNA repair and DNA-damage-induced BclxL deamidation in T cell transformation. Zhao R, 2004). Following that I have tried to elucidate the different roles of the two deamidated species of Bcl-xL in apoptosis, and also the molecular mechanisms of DNA damage- induced Bcl-xL deamidation in order to understand the inhibition of Bcl-xL deamidation by oncogenic tyrosine kinases. Recently I have shown that Bcl-xL deamidation, whereby two critical Asn residues are converted to iso-Asp, cripples the ability of the protein to sequester pro-apoptotic BH3-only proteins such as Bim and p53- upregulated modulator of apoptosis (PUMA), thereby explaining its loss of pro-survival functionality. In vivo, DNA damage causes intracellular alkalinisation that is both necessary and sufficient to deamidate Bcl-xL, promoting apoptosis: no enzyme is necessary for this process. In pre-tumourigenic thymocytes alkalinisation is blocked, so preserving Bcl-xL in its pro-survival mode. Furthermore murine tumours are protected from genotoxic attack by native Bcl-xL, but enforced alkalinisation and consequent Bcl-xL deamidation promotes apoptosis. This part of work was published in Plos Biology (DNA damage-induced Bcl-xL deamidation is mediated by NHE-1 antiport regulated intracellular pH. Zhao R, 2007). Through collaboration with Prof AR Green’s research group at the Department of Haematology of the University of Cambridge, I have also analysed the Bcl-xL deamidation pathway in human myeloproliferative disorders, e.g. Polycythemia vera(PV) and Chronic Myelogenous Leukaemia (CML). We found that the oncogenic tyrosine kinases involved in these disorders, i.e. Jak2V617F and Bcr-Abl also inhibit the Bcl-xL deamidation pathway in DNA damage responses. These findings shed light on potential therapeutic application of the Bcl-xL deamidation pathway in human malignancies. This piece of work was recently published in the New England Journal of Medicine (Inhibition of the Bcl-xL deamidation pathway in myeloproliferative disorders. Zhao R, 2008). Overall the cited work has led to several important new insights into the molecular mechanisms involved in oncogenesis: first, that Bcl-xL deamidation is important in the cascade of events leading from DNA damage to apoptosis; second, that oncogenic tyrosine kinases inhibit these events in both the murine and human context; third, that up-regulation of the NHE-1 antiport and consequent intracellular alkalinisation are critical events in this DNA damage-induced cascade leading to apoptosis. In the process I have demonstrated the first in vivo mechanism for the deamidation of an internal protein Asn. Essentially, a completely new and unexpected signalling pathway has been uncovered that seems to pertain to all murine and human haematopoietic cell lineages that have been investigated so far.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.

Fibrosis in the bone marrow is usually denominated myelofibrosis and may contribute to impaired hematopoiesis. Myelofibrosis is seen both in malignant and non-malignant diseases. The normal microenvironment in the bone marrow consists of a heterogenous population of hematopoietic and non-hematopoietic stromal cells, their extracellular products and hematopoietic cytokines. The stromal cells produce a complex array of molecules, among others collagens and glycosaminoglycans (GAGs) of which hyaluronan (HYA) is the most abundant. Marrow fibrosis results from an increased deposition of collagens, which are polypeptides. Staining for reticulin, mostly composed of collagen type III, is the common way of visualizing myelofibrosis. HYA, like the collagens, is widely distributed in connective tissues. Little is known about the distribution of HYA in bone marrow. The aims of this thesis have been to determine how HYA is distributed in normal and malignant bone marrow, compared to reticulin staining, and to follow patients with chronic myeloproliferative diseases (CMPD) during two years treatment with anagrelide considering development of cellularity and fibrosis. In bone marrow biopsies from healthy volunteers, the controls, HYA was found in a pattern that was concordant with the reticulin staining. Comparing patients with different malignant diseases with and without bone marrow involvemen, HYA staining was found to be significantly stronger in both groups compared to the controls. The HYA scores were also significantly higher in the bone marrow of patients with de novo acute myeloid leukemia (AML), compared to the controls. There was a correlation between HYA and reticulin in the patients with de novo AML, and in the patients with different malignant diseases with and without bone marrow involvement as in the controls. Increase of HYA, reticulin and cellularity in the bone marrow of patients with CMPD after two years of treatment with anagrelide indicated progression of fibrosis. Anagrelide is a valuable drug for reduction of platelets but seems unable to stop progression of fibrosis and hypercellularity. HYA is an interesting molecule with properties not only contributing to the structure of extracellular matrix but also to cell signaling and behaviour, although the understanding of the detailed mechanisms is still incomplete.

Background: Chronic myeloproliferative disorders (CMPD) seem to be associated with an increased risk for pulmonary hypertension (PH). Case Report: A patient with history of chronic idiopathic myelofibrosis (CIMF) presented with progressive dyspnea (New York Heart Association class III). Until this time he had not received specific treatment for CIMF. Echocardiography and rightheart catheterization confirmed PH. Further diagnostic procedures excluded a specific cause of PH. Therefore, primary PH was assumed. 2 years later he presented again with progressive dyspnea due to a progress of PH. A few days later the patient died from acute posterior myocardial infarction. Pathologic examination of the lung showed an obstruction of the small vessels by conglomerates of megakaryocytes. Discussion: We conclude that PH developed secondarily due to CMPD. PH should be suspected in patients with CMPD and should influence the decision for treatment of CMPD. / Hintergrund: Chronische myeloproliferative Erkrankungen (CMPD) scheinen mit einem erhöhten Risiko für pulmonale Hypertonie (PH) assoziiert zu sein. Kasuistik: Ein Patient mit chronisch idiopathischer Myelofibrose (CIMF) wurde aufgrund einer progressiven Belastungsdyspnoe (New York Heart Association Stadium III) überwiesen. Bis zu diesem Zeitpunkt erhielt er keine spezifische Behandlung seiner CIMF. Echokardiographie und Rechtsherzkatheter ergaben das Vorliegen einer PH. Eine spezifische Ursache der PH konnte zunächst ausgeschlossen werden. Somit wurde das Vorliegen einer primären PH vermutet. 2 Jahre später wurde der Patient mit erneut verschlechterter Belastungsdyspnoe vorgestellt, wobei ein Progress der PH feststellbar war. Einige Tage später verstarb der Patient an einem Hinterwandinfarkt. Die Autopsie des Lungengewebes zeigte einen Verschluss der kleinen Lungengefäße durch Konglomerate von Megakaryozyten. Diskussion: Die Entwicklung der PH ist bei diesem Patienten als Folge der CMPD einzuschätzen. Das Vorliegen einer PH bei Patienten mit CMPD sollte die Entscheidung zu spezifischen therapeutischen Maßnahmen hinsichtlich der CMPD beeinflussen. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

As neoplasias mieloproliferativas (NMPs) Filadelfia negativo como a policitemia vera (PV), trombocitemia essencial (TE) e mielofibrose primária (MFP) são desordens clonais da célula tronco hematopoiética caracterizadas pela produção excessiva de células mielóides diferenciadas. Este fenômeno ocorre devido à uma mutação somática (JAK2V617F) que ativa a via JAK-STAT de transdução de forma constitutiva. Esta mutação é mais frequente na PV, ocorrendo em 95% dos casos, e em 50% dos casos de TE e MFP. Outro defeito genético que ocorre é a mutação no receptor de trombopoetina, MPL. As mutações em MPL podem ser germinativas ou somáticas e menos de 10% dos pacientes com TE e MFP apresentam essa alteração genética. Entretanto, grande parte dos pacientes com TE e MFP que não apresentam mutação em JAK2V617F ou MPL podem apresentar mutações somáticas no gene CALR. Em adição às mutações somáticas que causam mieloproliferação, outras alterações genéticas em genes que funcionam como reguladores epigenéticos são encontrados nas NMPs nos genes TET2, IDH1, IDH2 e ASLX1. Objetivo: Estabelecer um perfil genético em pacientes com NMP através da avaliação de mutações nos genes JAK2, CALR, MPL, IDH1, IDH2, TET2 e ASXL1 assim como estabelecer uma correlação laboratorial destas na PV, TE e MFP. Casuística e Métodos: Foram utilizadas amostras de sangue periférico de 104 pacientes que foram enviadas para o Laboratório de Biologia Tumoral do Serviço de Hematologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo para avaliação diagnóstica. Quinze dos 104 pacientes são de pacientes com PV (14,4%), 20/104 (19,2%) com MFP, 20/104 (19,2%) com TE e 49/104 (47,1%) com outras doenças hemtológicas. Foi feita a avaliação da prevalência de mutações somáticas, seja por sequenciamento ou análise de fragmentos, nos genes JAK2 (exon 12 e Y931C), MPL, IDH1, IDH2, CALR, TET2 e ASXL1. PCR-RFLP foi realizada para identificação de mutações em JAK2V617F. Resultados: A mutação JAK2V617F foi observada em 30 (28,8%) pacientes (12 PV, 11 TE e 7 MFP), a mutação JAK2 exon 12 foi observada em apenas um (0,96%) paciente com PV, mutação JAK2Y931C em 4 (3,8%) pacientes (1 PV, 2 TE e 1 MFP) e 8 (7,7%) pacientes apresentaram mutações em CALR (3 TE e 5 MFP). Mutações nos genes epigenéticos como IDH1 foram observadas em 9 (8,7%) pacientes (2 TE, 2 MFP, 1 SMD, e 4 pacientes com suspeita de NMP), mutações em IDH2 estão presentes em 5 (4,8%) pacientes (2 TE, 1 SMD/leucemia e 4 pacientes com suspeita de NMP), mutações em ASXL1 foram identificadas em 13 (12,5%) pacientes (1 PV, 3 TE, 2 MFP, 3 SMD/leucemias e 4 com suspeita de NMP) e finalmente, mutações em TET2 foram encontradas em 33 (31,7%) pacientes (3 PV, 5 TE, 4 MFP, 8 SMD/leucemias e 13 pacientes com suspeita de NMP). Além disso, no caso da PV, os pacientes que apresentam mutações em JAK2V617F apresentam valores aumentados de plaquetas (mediana de 5,41 x 105/mm3 plaquetas) em relação aos pacientes sem a mutação (mediana de 2,06 x 105/mm3 plaquetas), com diferença estatística (p=0,031). Pacientes do mesmo grupo que apresentam mutações em TET2 apresentam, opostamente aos com mutações em JAK2V617F, menores valores de plaquetas (mediana de 1,75 x105/mm3 plaquetas) em relação aos pacientes sem mutações no gene TET2 (mediana de 5,41 x 105/mm3 plaquetas), com diferença estatística (p=0,048). No caso da MFP, os pacientes que apresentam mutações em JAK2V617F apresentam valores maiores de leucócitos (mediana de 1,09 x104/mm3 leucócitos) do que os pacientes que não apresentam a mutação (mediana de 6,99 x103/mm3 leucócitos) com diferença estatística (p=0,046), já os pacientes que apresentam mutações no gene ASXL1 apresentam valores menores de hemácias (mediana de 2,43 x106/mm3 hemácias) em relação aos pacientes que não apresentam mutação (mediana de 3,71 x106/mm3 hemácias) com diferença estatística (p=0,042). Conclusão: O trabalho permitiu fornecer um perfil genético dos pacientes com NMP estudados. Além disso, é possível observar que algumas mutações epigenéticas podem influenciar em diferenças clínicas / Myeloproliferative neoplasms (MPNs) Philadelphia (Ph) chromosome negative, such as polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) are clonal disorders of hematopoietic stem cell characterized by increased proliferation of differentiated myeloid cells. This phenomenon occurs due somatic mutation (JAK2V617F) that constitutively stimulates the JAK-STAT signaling pathway. This mutation is more frequent in PV, around 95%, and between 50% in ET and PMF. Other genetic aberration can be observed in the thrombopoietin (TPO) receptor MPL. Mutations in MPL can be in the germline line or somatic and less than 10% of patients with TE or PMF would harbor this genetic alteration. Otherwise, patients with TE or PMF without JAK2V617F or MPL mutation could present somatic mutations in calreticulin (CALR). In addition to somatic mutations that cause myeloproliferation, other genetic alterations that function as epigenetic regulators were identified in genes as TET2, IDH1, IDH2 e ASLX1 in MPN. Objective: Establish genetic profile in patients with diagnosis of PV, ET, and PMF through genetic alterations in the following genes: JAK2, MPL, CALR, IDH1, IDH2, TET2 e ASXL1, and correlate those alterations with demographic characteristic of the study population. Casuistic and Methods: Peripheral blood samples from 104 patients referred to the Tumor Biology Laboratory of the Department of Hematology of Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo for diagnostic investigation were analyzed. Fifteen out 104 samples were from PV patients (14.4%), 20/104 (19.2%) in PMF, 20/104 (19.2%) in ET and 49/104 (47.1%) with other hematologic diseases. Identification of somatic mutations was made, either by direct sequencing or fragment analysis in JAK2 (exon 12 and Y931C), MPL, IDH1, IDH2, CALR, TET2 and ASXL1. PCR-RFLP was performed to identify JAK2V617F mutation. Results: JAK2V617F mutation was observed in 30 (28.8%) patients (12 PV, 11 ET and 7 PMF), JAK2 exon 12 in only one (0.96%) patient with PV, JAK2Y931C in 4 (3.8%) patients (1 PV, 2 ET and 1 PMF), and 8 patients (7.7%) presented CALR mutation (3 ET and 5 PMF). Mutations in the epigenetic genes as IDH1 were observed in 9 (8.7%) patients (2 ET, 2 PMF, 1 MDS and 4 patients with suspected MPN), IDH2 mutations were present in 5 (4.8%) patients (2 ET, 1 MDS/leukemia, and 4 patients with suspected MPN), ASLX1 mutations were identified in 13 (12.5%) patients (1 PV, 3 ET, 2 PMF, 3 MDS/leukemia and 4 with suspected MPN) and finally, TET2 mutations were present in 33 (31.7%) patients (3 PV, 5 ET, 4 PMF, 8 MDS/leukemia, and 13 with suspected MPN). In addition, patients with PV who harbor JAK2V617F have increased platelet counts (median 5.41 x 105/mm3 platelets) compared to those without the mutation (median 2.06 x 105/mm3 platelets, p=0.031). Patients in the same group with TET2 mutation, as opposed to those with JAK2V617F, presented low platelets counts (median of 1.75 x 105/mm3 platelets) compared to those without TET2 mutation (median 5.41 x 105/mm3 platelets, p=0.048). Presence of JAK2V617F in patients diagnosed with PMF have a greater number of leukocytes (median 1.09 x104/mm3 leukocytes) when compared to patients without the mutation (median 6.99 x 103/mm3 leukocytes, p=0.046). Patients with PMF who presented mutations in ASXL1 gene have a lower number of red blood cells (median of 2.43 x 106/mm3) compared to patients without mutations in the same gene (median 3.71 x 106/mm3, p=0.042). Conclusion: The present study allows us to provide a genetic profile of patients with MPN. Furthermore, it is possible to observe that some epigenetic mutations could influence in some clinical differences

As neoplasias mieloproliferativas (NMPs) Filadelfia negativo como a policitemia vera (PV), trombocitemia essencial (TE) e mielofibrose primária (MFP) são desordens clonais da célula tronco hematopoiética caracterizadas pela produção excessiva de células mielóides diferenciadas. Este fenômeno ocorre devido à uma mutação somática (JAK2V617F) que ativa a via JAK-STAT de transdução de forma constitutiva. Esta mutação é mais frequente na PV, ocorrendo em 95% dos casos, e em 50% dos casos de TE e MFP. Outro defeito genético que ocorre é a mutação no receptor de trombopoetina, MPL. As mutações em MPL podem ser germinativas ou somáticas e menos de 10% dos pacientes com TE e MFP apresentam essa alteração genética. Entretanto, grande parte dos pacientes com TE e MFP que não apresentam mutação em JAK2V617F ou MPL podem apresentar mutações somáticas no gene CALR. Em adição às mutações somáticas que causam mieloproliferação, outras alterações genéticas em genes que funcionam como reguladores epigenéticos são encontrados nas NMPs nos genes TET2, IDH1, IDH2 e ASLX1. Objetivo: Estabelecer um perfil genético em pacientes com NMP através da avaliação de mutações nos genes JAK2, CALR, MPL, IDH1, IDH2, TET2 e ASXL1 assim como estabelecer uma correlação laboratorial destas na PV, TE e MFP. Casuística e Métodos: Foram utilizadas amostras de sangue periférico de 104 pacientes que foram enviadas para o Laboratório de Biologia Tumoral do Serviço de Hematologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo para avaliação diagnóstica. Quinze dos 104 pacientes são de pacientes com PV (14,4%), 20/104 (19,2%) com MFP, 20/104 (19,2%) com TE e 49/104 (47,1%) com outras doenças hemtológicas. Foi feita a avaliação da prevalência de mutações somáticas, seja por sequenciamento ou análise de fragmentos, nos genes JAK2 (exon 12 e Y931C), MPL, IDH1, IDH2, CALR, TET2 e ASXL1. PCR-RFLP foi realizada para identificação de mutações em JAK2V617F. Resultados: A mutação JAK2V617F foi observada em 30 (28,8%) pacientes (12 PV, 11 TE e 7 MFP), a mutação JAK2 exon 12 foi observada em apenas um (0,96%) paciente com PV, mutação JAK2Y931C em 4 (3,8%) pacientes (1 PV, 2 TE e 1 MFP) e 8 (7,7%) pacientes apresentaram mutações em CALR (3 TE e 5 MFP). Mutações nos genes epigenéticos como IDH1 foram observadas em 9 (8,7%) pacientes (2 TE, 2 MFP, 1 SMD, e 4 pacientes com suspeita de NMP), mutações em IDH2 estão presentes em 5 (4,8%) pacientes (2 TE, 1 SMD/leucemia e 4 pacientes com suspeita de NMP), mutações em ASXL1 foram identificadas em 13 (12,5%) pacientes (1 PV, 3 TE, 2 MFP, 3 SMD/leucemias e 4 com suspeita de NMP) e finalmente, mutações em TET2 foram encontradas em 33 (31,7%) pacientes (3 PV, 5 TE, 4 MFP, 8 SMD/leucemias e 13 pacientes com suspeita de NMP). Além disso, no caso da PV, os pacientes que apresentam mutações em JAK2V617F apresentam valores aumentados de plaquetas (mediana de 5,41 x 105/mm3 plaquetas) em relação aos pacientes sem a mutação (mediana de 2,06 x 105/mm3 plaquetas), com diferença estatística (p=0,031). Pacientes do mesmo grupo que apresentam mutações em TET2 apresentam, opostamente aos com mutações em JAK2V617F, menores valores de plaquetas (mediana de 1,75 x105/mm3 plaquetas) em relação aos pacientes sem mutações no gene TET2 (mediana de 5,41 x 105/mm3 plaquetas), com diferença estatística (p=0,048). No caso da MFP, os pacientes que apresentam mutações em JAK2V617F apresentam valores maiores de leucócitos (mediana de 1,09 x104/mm3 leucócitos) do que os pacientes que não apresentam a mutação (mediana de 6,99 x103/mm3 leucócitos) com diferença estatística (p=0,046), já os pacientes que apresentam mutações no gene ASXL1 apresentam valores menores de hemácias (mediana de 2,43 x106/mm3 hemácias) em relação aos pacientes que não apresentam mutação (mediana de 3,71 x106/mm3 hemácias) com diferença estatística (p=0,042). Conclusão: O trabalho permitiu fornecer um perfil genético dos pacientes com NMP estudados. Além disso, é possível observar que algumas mutações epigenéticas podem influenciar em diferenças clínicas / Myeloproliferative neoplasms (MPNs) Philadelphia (Ph) chromosome negative, such as polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) are clonal disorders of hematopoietic stem cell characterized by increased proliferation of differentiated myeloid cells. This phenomenon occurs due somatic mutation (JAK2V617F) that constitutively stimulates the JAK-STAT signaling pathway. This mutation is more frequent in PV, around 95%, and between 50% in ET and PMF. Other genetic aberration can be observed in the thrombopoietin (TPO) receptor MPL. Mutations in MPL can be in the germline line or somatic and less than 10% of patients with TE or PMF would harbor this genetic alteration. Otherwise, patients with TE or PMF without JAK2V617F or MPL mutation could present somatic mutations in calreticulin (CALR). In addition to somatic mutations that cause myeloproliferation, other genetic alterations that function as epigenetic regulators were identified in genes as TET2, IDH1, IDH2 e ASLX1 in MPN. Objective: Establish genetic profile in patients with diagnosis of PV, ET, and PMF through genetic alterations in the following genes: JAK2, MPL, CALR, IDH1, IDH2, TET2 e ASXL1, and correlate those alterations with demographic characteristic of the study population. Casuistic and Methods: Peripheral blood samples from 104 patients referred to the Tumor Biology Laboratory of the Department of Hematology of Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo for diagnostic investigation were analyzed. Fifteen out 104 samples were from PV patients (14.4%), 20/104 (19.2%) in PMF, 20/104 (19.2%) in ET and 49/104 (47.1%) with other hematologic diseases. Identification of somatic mutations was made, either by direct sequencing or fragment analysis in JAK2 (exon 12 and Y931C), MPL, IDH1, IDH2, CALR, TET2 and ASXL1. PCR-RFLP was performed to identify JAK2V617F mutation. Results: JAK2V617F mutation was observed in 30 (28.8%) patients (12 PV, 11 ET and 7 PMF), JAK2 exon 12 in only one (0.96%) patient with PV, JAK2Y931C in 4 (3.8%) patients (1 PV, 2 ET and 1 PMF), and 8 patients (7.7%) presented CALR mutation (3 ET and 5 PMF). Mutations in the epigenetic genes as IDH1 were observed in 9 (8.7%) patients (2 ET, 2 PMF, 1 MDS and 4 patients with suspected MPN), IDH2 mutations were present in 5 (4.8%) patients (2 ET, 1 MDS/leukemia, and 4 patients with suspected MPN), ASLX1 mutations were identified in 13 (12.5%) patients (1 PV, 3 ET, 2 PMF, 3 MDS/leukemia and 4 with suspected MPN) and finally, TET2 mutations were present in 33 (31.7%) patients (3 PV, 5 ET, 4 PMF, 8 MDS/leukemia, and 13 with suspected MPN). In addition, patients with PV who harbor JAK2V617F have increased platelet counts (median 5.41 x 105/mm3 platelets) compared to those without the mutation (median 2.06 x 105/mm3 platelets, p=0.031). Patients in the same group with TET2 mutation, as opposed to those with JAK2V617F, presented low platelets counts (median of 1.75 x 105/mm3 platelets) compared to those without TET2 mutation (median 5.41 x 105/mm3 platelets, p=0.048). Presence of JAK2V617F in patients diagnosed with PMF have a greater number of leukocytes (median 1.09 x104/mm3 leukocytes) when compared to patients without the mutation (median 6.99 x 103/mm3 leukocytes, p=0.046). Patients with PMF who presented mutations in ASXL1 gene have a lower number of red blood cells (median of 2.43 x 106/mm3) compared to patients without mutations in the same gene (median 3.71 x 106/mm3, p=0.042). Conclusion: The present study allows us to provide a genetic profile of patients with MPN. Furthermore, it is possible to observe that some epigenetic mutations could influence in some clinical differences