• Tuberculosis and Respiratory Diseases
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• v.67 no.3
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• pp.244-248
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• 2009

Primary myelofibrosis is characterized by replacement of bone marrow with fibrotic tissue and the development of extramedullary hematopoiesis. Extramedullary hematopoiesis primarily involves the spleen and liver, but can also occur in the lungs. We report the case of an 80-year-old male who was admitted for evaluation of a lung mass and persistent thrombocytopenia. A percutaneous needle aspiration from the mass in the right lower lung showed myelopoietic cells with fatty tissue. A bone marrow biopsy revealed a hypercellular marrow with an increased number of atypical megakaryocytes. The final diagnosis was a prefibrotic stage of primary myelofibrosis leading to extramedullary hematopoiesis in the lung.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8629-8631
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• 2016

Background: Primary idiopathic myelofibrosis (PMF) is a clonal Philadelphia chromosome-negative myeloproliferative neoplasm characterized by extramedullary hematopoiesis and marrow fibrosis. It is an uncommon hematopoietic malignancy which primarily affects elderly individuals. The rational of this study was to determine its clinico-epidemiological profile along with risk stratification in Pakistani patients. Materials and Methods: In this retrospective cross sectional study, 20 patients with idiopathic myelofibrosis were enrolled from January 2011 to December 2014. Data were analyzed with SPSS version 22. Results: The mean age was $57.9{\pm}16.5years$ with 70% of patients aged above 50. The male to female ratio was 3:1. Overall only 10% of patients were asymptomatic and the remainder presented with constitutional symptoms. In symptomatic patients, major complaints were weakness (80%), weight loss (75%), abdominal discomfort (60%), night sweats (13%), pruritus (5%) and cardiovascular accidents (5%). Physical examination revealed splenomegaly as a predominant finding detected in 17 patients (85%) with the mean splenic span of $22.2{\pm}2.04cm$. The mean hemoglobin was $9.16{\pm}2.52g/dl$ with the mean MCV of $88.2{\pm}19.7fl$. The total leukocyte count of $17.6{\pm}19.2{\times}10^9/l$ and platelets count were $346.5{\pm}321.9{\times}10^9/l$. Serum lactate dehydrogenase, serum creatinine and uric acid were $731.0{\pm}154.1$, $0.82{\pm}0.22$ and $4.76{\pm}1.33$ respectively. According to risk stratification, 35% were in high risk, 40% in intermediate risk and 25% in low risk groups. Conclusions: The majority of PMF patients were male and presented with constitutional symptoms in our setting. Risk stratification revealed predominance of advanced disease in our series.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7889-7892
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• 2015

Background: Primary idiopathic myelofibrosis (PMF) is a clonal Ph-chromosome negative myeloproliferative neoplasm characterized by dysregulated kinase signaling and release of abnormal cytokines. In the recent past, following JAK2 V617F mutation invention, important revolution has been made in the molecular diagnostic biology of this disease. The rational of this study was to determine the mutational status of JAK2 V617F in Pakistan patients with PMF. Materials and Methods: In this cross sectional study, 20 patients with PMF were enrolled from January 2011 to December 2014. Diagnosis was based on WHO criteria for PMF. All patients were screened for G-T point mutation (V617F) in the JAK2 gene on chromosome 9 by allele specific PCR. Results: The mean age was $57.9{\pm}16.5years$. The male to female ratio was 3:1. The frequency of JAK2 V617F positivity in our PMF patients was found to be 55%. Positive correlations of JAK2 V617F mutation were established with high TLC count, raised LDH and marked splenomegaly (P<0.05). No correlation of JAK2 V617F could be established with age and gender (P>0.05). Conclusions: The JAK2 V617F mutation frequency in our PMF patients was similar to those reported previously. In our hands JAK2 V617F mutated patients expressed an aggressive disease phenotype. Screening for the mutation in all suspected PMF cases could be beneficial in differentiating patients with reactive and clonal marrow fibrosis.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.5013-5018
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• 2015

Background: Myeloproliferative neoplasms (MPNs) are clonal hematopoietic stem cell disorders characterized by proliferation of one or more myeloid lineages. Polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) are classical Philadelphia chromosome (Ph)-negative MPN that have a Janus Kinase 2 (JAK2) mutation, especially JAK2V617F in the majority of patients. The major complications of Ph-negative MPNs are thrombosis, hemorrhage, and leukemic transformation. Objective: To study clinical manifestations including symptoms, signs, laboratory findings, and JAK2V617F mutations of Ph-negative MPN (PV, ET and PMF) as well as their complications. Materials and Methods: All Ph-negative MPN (PV, ET and PMF) patients who attended the Hematology Clinic at Maharaj Nakorn Chiang Mai Hospital from January, 1 2003 through December, 31 2013 were retrospectively reviewed for demographic data, clinical characteristics, complete blood count, JAK2V617F mutation analysis, treatment, and complications. Results: One hundred and fifty seven patients were included in the study. They were classified as PV, ET and PMF for 68, 83 and 6 with median ages of 60, 61, and 68 years, respectively. JAK2V617F mutations were detected in 88%, 69%, and 100% of PV, ET and PMF patients. PV had the highest incidence of thrombosis (PV 29%, ET 14%, and PMF 0%) that occurred in both arterial and venous sites whereas PMF had the highest incidence of bleeding (PMF 17%, ET 11%, and PV 7%). During follow up, there was one ET patient that transformed to acute leukemia and five cases that developed thrombosis (three ET and two PV patients). No secondary myelofibrosis and death cases were encountered. Conclusions: Ph-negative MPNs have various clinical manifestations. JAK2V617F mutations are present in the majority of PV, ET, and PMF patients. This study confirmed that thrombosis and bleeding are the most significant complications in patients with Ph-negative MPN.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.923-926
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• 2016

The classic BCR-ABL1-negative myeloproliferative neoplasm is an operational sub-category of MPNs that includes polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). The JAK2V617F mutation is found in ~ 95% of PV and 50-60% of ET or PMF. In most of the remaining JAK2V617F-negative PV cases, JAK2 exon 12 mutations are present. Amongst the JAK2V617F-negative ET or PMF 5-10% of patients carry mutations in the MPL gene. Prior to 2013, there was no specific molecular marker described in the remaining 30-40% ET and PMF. In December 2013, two research groups independently reported mutations in the gene CALR found specifically in ET (67-71%) and PMF (56-88%) but not in PV. Initially CALR mutations were reported mutually exclusive with JAK2 or MPL. However, co-occurrence of CALR mutations with JAK2V617F has been reported recently in a few MPN cases. Many studies have reported important diagnostic and prognostic significance of CALR mutations in ET and PMF patients and CALR mutation screening has been proposed to be incorporated into WHO diagnostic criteria for MPN. It is suggestive in diagnostic workup of MPN that CALR mutations should not be studied in MPN patients who carry JAK2 or MPL mutations. However JAK2V617F and CALR positive patients might have a different phenotype and clinical course, distinct from the JAK2-positive or CALR-positive subgroups and identification of the true frequency of these patients may be an important factor for defining the prognosis, risk factors and outcomes for MPN patients.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.10
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• pp.4647-4653
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• 2016

Background: The discovery of somatic acquired mutations of JAK2 (V617F) in Philadelphia-negative myeloproliferative neoplasms (Ph-negative MPNs) including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) has not only improved rational disease classification and prognostication but also brings new understanding insight into the pathogenesis of diseases. Dosage effects of the JAK2 (V617F) allelic burden in Ph-negative MPNs may partially influence clinical presentation, disease progression, and treatment outcome. Material and Methods: Pyrosequencing was performed to detect JAK2 (V617F) and MPL (W515K/L) and capillary electrophoresis to identify CALR exon 9 mutations in 100 samples of Ph-negative MPNs (38.0 PV, 55 ET, 4 PMF, and 3 MPN-U). Results: The results showed somatic mutations of JAK2 (V617F) in 94.7% of PV, 74.5% of ET, 25.0% of PMF, and all MPN-U. A high proportion of JAK2 (V617F) mutant allele burden (mutational load > 50.0%) was predominantly observed in PV when compared with ET. Although a high level of JAK2 (V617F) allele burden was strongly associated with high WBC counts in both PV and ET, several hematological parameters (hemoglobin, hematocrit, and platelet count) were independent of JAK2 (V617F) mutational load. MPL (W515K/L) mutations could not be detected whereas CALR exon 9 mutations were identified in 35.7% of patients with JAK2 negative ET and 33.3% with JAK2 negative PMF. Conclusions: The JAK2 (V617F) allele burden may be involved in progression of MPNs. Furthermore, a high level of JAK2 (V617F) mutant allele appears strongly associated with leukocytosis in both PV and ET.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2219-2225
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• 2015

SHP1 negatively regulates the Janus kinase 2/signal transducer and activator of transcription (JAK2/STAT) signaling pathway, which is constitutively activated in myeloproliferative neoplasms (MPNs) and leukemia. Promoter hypermethylation resulting in epigenetic inactivation of SHP1 has been reported in myelomas, leukemias and other cancers. However, whether SHP1 hypermethylation occurs in MPNs, especially in Chinese patients, has remained unclear. Here, we report that aberrant hypermethylation of SHP1 was observed in several leukemic cell lines and bone marrow mononuclear cells from MPN patients. About 51 of 118 (43.2%) MPN patients including 23 of 50 (46%) polycythaemia vera patients, 20 of 50 (40%) essential thrombocythaemia and 8 of 18 (44.4%) idiopathic myelofibrosis showed hypermethylation by methylation-specific polymerase chain reaction. However, SHP1 methylation was not measured in 20 healthy volunteers. Hypermethylation of SHP1 was found in MPN patients with both positive (34/81, 42%) and negative (17/37, 45.9%) JAK2V617F mutation. The levels of SHP1 mRNA were significantly lower in hypermethylated samples than unmethylated samples, suggesting SHP1 may be epigenetically inactivated in MPN patients. Furthermore, treatment with 5-aza-2'-deoxycytidine (AZA) in K562 cells showing hypermethylation of SHP1 led to progressive demethylation of SHP1, with consequently increased reexpression of SHP1. Meanwhile, phosphorylated JAK2 and STAT3 were progressively reduced. Finally, AZA increased the expression of SHP1 in primary MPN cells with hypermethylation of SHP1. Therefore, our data suggest that epigenetic inactivation of SHP1 contributes to the constitutive activation of JAK2/STAT signaling. Restoration of SHP1 expression by AZA may contribute to clinical treatment for MPN patients.