Alterations of the expression of TET2 and DNA 5-hmC predict poor prognosis in Myelodysplastic Neoplasms.

BACKGROUND: Myelodysplastic Neoplasms (MDS) are clonal stem cell disorders characterized by ineffective hematopoiesis and progression to acute myeloid leukemia, myelodysplasia-related (AML-MR). A major mechanism of pathogenesis of MDS is the aberration of the epigenetic landscape of the hematopoietic stem cells and/or progenitor cells, especially DNA cytosine methylation, and demethylation. Data on TET2, the predominant DNA demethylator of the hematopoietic system, is limited, particularly in the MDS patients from India, whose biology may differ since these patients present at a relatively younger age. We studied the expression and the variants of TET2 in Indian MDS and AML-MR patients and their effects on 5-hydroxymethyl cytosine (5-hmC, a product of TET2 catalysis) and on the prognosis of MDS patients. RESULTS: Of the 42 MDS patients, cytogenetics was available for 31 sub-categorized according to the Revised International Prognostic Scoring System (IPSS-R). Their age resembled that of the previous studies from India. Bone marrow nucleated cells (BMNCs) were also obtained from 13 patients with AML-MR, 26 patients with de-novo AML, and 11 subjects with morphologically normal bone marrow. The patients had a significantly lower TET2 expression which was more pronounced in AML-MR and the IPSS-R higher-risk MDS categories. The 5-hmC levels in higher-risk MDS and AML-MR correlated with TET2 expression, suggesting a possible mechanistic role in the loss of TET2 expression. The findings on TET2 and 5-hmC were also confirmed at the tissue level using immunohistochemistry. Pathogenic variants of TET2 were found in 7 of 24 patient samples (29%), spanning across the IPSS-R prognostic categories. One of the variants - H1778R - was found to affect local and global TET2 structure when studied using structural predictions and molecular dynamics simulations. Thus, it is plausible that some pathogenic variants in TET2 can compromise the structure of TET2 and hence in the formation of 5-hmC. CONCLUSIONS: IPSS-R higher-risk MDS categories and AML-MR showed a reduction in TET2 expression, which was not apparent in lower-risk MDS. DNA 5-hmC levels followed a similar pattern. Overall, a decreased TET2 expression and a low DNA 5-hmC level are predictors of advanced disease and adverse outcome in MDS in the population studied, i.e., MDS patients from India.

Increased Expression of NOTCH-1 and T Helper Cell Transcription Factors in Patients with Acquired Aplastic Anemia.

Background: Acquired aplastic anemia is an autoimmune disease in which auto-aggressive T cells destroy hematopoietic progenitors. T-cell differentiation is controlled by transcription factors that interact with NOTCH-1, which influences the respective T-cell lineages. Notch signaling also regulates the BM microenvironment. The present study aimed to assess the gene expressions of NOTCH-1 and T helper cell transcription factors in the acquired aplastic anemia patients. Methods: Using quantitative real-time PCR, we studied the mRNA expression level for NOTCH-1, its ligands (DLL-1 and JAG-1), and T helper cell transcription factors (T-BET, GATA-3, and ROR-γt) in both PB and BM of aAA patients and healthy controls. Further, patients of aplastic anemia were stratified by their disease severity as per the standard criteria. Results: The mRNA expression level of NOTCH-1, T-BET, GATA-3, and ROR-γT genes increased in aAA patients compared to healthy controls. There was no significant difference in the mRNA expression of Notch ligands between patients and controls. The mRNA expression level of the above-mentioned genes was found to be higher in SAA and VSAA than NSAA patients. In addition, NOTCH-1 and T helper cell-specific transcription factors enhanced in aAA. We also observed a significant correlation between the genes and hematological parameters in patients. Conclusion: The interaction between NOTCH-1, T-BET, GATA-3, and ROR-γT might lead to the activation, proliferation, and polarization of T helper cells and subsequent BM destruction. The mRNA expression levels of genes varied with disease severity, which may contribute to pathogenesis of aAA.

Influence of JAK2V617F allele burden on clinical phenotype of polycythemia vera patients: A study from India.

BACKGROUND: Elevated JAK2V617F allele burden is associated with enhanced expression of downstream target genes in Philadelphia negative chronic myeloproliferative neoplasms (CMPNs) which include PV, ET & PMF. Previous studies have shown the impact of JAK2V617F allele burden on clinical phenotype of CMPNs. However, there is no data from India regarding the association between JAK2V617F allele burden and clinical phenotype in PV. AIMS/SETTINGS AND DESIGN: We aimed to investigate the effect of allele burden on clinical phenotype in 90 JAK2V617F positive PV patients and to see its influence on disease related complications. MATERIAL AND METHODS: Allele burden of 90 JAK2V617F positive PV patients was quantified by Real-time polymerase chain reaction (RQ-PCR). RESULTS: 74/90 (82.22%) were males and 16/90 (17.78%) were females (median 45 years, range 35-78). Patients with age >50 years had significantly higher JAK2V617F allele burden (median 40.15%, range 0.49-91.62 %) than patients with ≤ 50 years age (median 48.59 %, range 0.56-86.74 %; P < 0.032). Patients with splenomegaly had significantly higher JAK2V617F allele burden (mean 50.24%, range 6.91-84.17%) than patients without splenomegaly (mean 33.82 %, range 0.49-71.83 %; P < 0.017). Patients with higher allele burden (median 57.20, range 43.4-72.03%) had significantly raised thrombotic events than the patients with lower allele burden (median 37.38, range 0.49-84.17%; P < 0.043). 49/90 (54%) were homozygous and 41/90 (46%) were heterozygous. CONCLUSIONS: Higher JAK2V617F allele burden showed association with increased age, splenomegaly and thrombotic events. Thus, it may be considered for prognostication and setting up the treatment protocol in PV patients.

Distribution of common BCR-ABL fusion transcripts and their impact on treatment response in Imatinib treated CML patients: A study from India.

BACKGROUND: Philadelphia chromosome (Ph): Hallmark of CML is caused by reciprocal translocation between chromosomes 9 and 22 resulting in BCR-ABL fusion protein. Most commonly associated breakpoint with CML is M-bcr in exon 13 or exon 14, producing splice variant b2a2 or b3a2 respectively. The distribution of these transcripts and their influence on clinico-hematological parameters is variable. Impact of the fusion transcripts on treatment outcome in Imatinib treated CML patients is still a matter of debate. AIMS/SETTINGS AND DESIGN: We conducted this study on 400 CML-CP patients to look for the distribution of fusion transcripts i.e. b3a2 and b2a2, their clinico-hematological profile and impact on treatment response in patients treated with Imatinib. MATERIAL AND METHODS: CML-CP was diagnosed by reverse transcriptase PCR (RT-PCR) for the BCR-ABL fusion transcript. Real-time quantitative PCR (RQ-PCR) was performed on peripheral blood every 3-6 monthly to look for treatment response. RESULTS: The overall frequency of b3a2 transcript was observed in 288 (72%) followed by b2a2 in 104 (26%) and hybrid fusion transcript (b3a2 + b2a2) was seen in 8 (2%) cases. MMR was attained in 198/288 (68.7%) patients with b3a2 transcript and 90/288 (31.3%) patients failed to achieve MMR after 12 months of Imatinib therapy. Among the patients with b2a2 transcript, 44/104 (42.3%) patients achieved MMR and 60/104 (57.7%) patients failed to achieve MMR after 12 months of Imatinib therapy. CONCLUSIONS: In conclusion, the frequency of b3a2 transcript was more as compared to b2a2 transcript. MMR was significantly higher in patients with b3a2 transcript as compared to patients with b2a2.

Comparative analysis of the Sokal, Euro and European Treatment and Outcome Study score in prognostication of Indian chronic myeloid leukemia-chronic phase patients on imatinib.

INTRODUCTION: The ultimate goal for CML management is risk stratification of the patients to design the appropriate treatment approach. The Sokal, Euro and EUTOS risk scores were established to prognosticate the patients on therapy. AIM: To perform a comparative assessment of the Sokal, Euro and EUTOS prognostic score in Indian CML-CP patients on imatinib. METHODS: This is a retrospective study performed in 260 Ph+ CML-CP patients who were administered oral imatinib (400 mg/day). RESULTS: 166/260 were males and 94/260 were females (M: F::1.6:1) with median age 35 years (range 20-70). 92 (35.38%), 125 (48.07%) and 43 (16.5%) patients were divided into low, intermediate and high risk Sokal score respectively. 102 (39.23%), 106 (40.76%) and 52 (20%) patients were discriminated into low, intermediate and high risk Euro score respectively. 210 (80.7%) and 50 (19.2%) patients were divided into low and high risk EUTOS score. Cumulative incidence of MMR for low, intermediate and high-risk Sokal score was 87%, 76% and 84% respectively (P = 0.016). Incidence of MMR in low, intermediate and high-risk Euro score was 93%, 85% and 68% respectively (P = 0.001). Incidence of MMR was 80 % and 81% for low and high risk EUTOS score (P = 0.764). Both EFS and OS are significantly correlated with Sokal score (P = 0.004, P = 0.007) and Euro score (P = 0.009, P = 0.001) but not with EUTOS score (P = 0.581, P = 0.927). CONCLUSION: The present study highlights the significant prognostic role of Sokal and Euro score in predicting the treatment outcome of the CML- CP patients on imatinib.

Reversal of Glanzmann thrombasthenia platelet phenotype after imatinib treatment in a pediatric chronic myeloid leukemia patient.

Chronic Myelogenous Leukemia (CML) is a myeloproliferative neoplasm characterized by proliferation of Philadelphia positive clonal pluripotent hematopoietic cells. Bleeding is a rare presentation of CML that can occur due to platelet dysfunction. Both pre-treatment and post-treatment platelet function abnormalities in CML have been described in the literature. We describe a rare case of childhood CML who presented with mucocutateous bleeding manifestations. On laboratory workup, a Glanzmann Thrombasthenia (GT) like platelet phenotype was demonstrated along with confirmation of diagnosis of CML in chronic phase. The acquired nature of platelet function defect was confirmed by demonstrating recovery of platelet antigens glycoprotein IIb/IIIa after achieving complete hematological response with Imatinib. Due to presenting complaint of bleeding diathesis and absence of hepatosplenomegaly, the case was undiagnosed for CML until the patient reported to us. Careful evaluation of complete blood counts, peripheral blood picture and detailed laboratory workup was the window to proper diagnosis and treatment in this case.

NPM1 and FLT3 mutations in acute myeloid leukemia with normal karyotype: Indian perspective.

BACKGROUND: FLT3-ITD and NPM1 mutations are considered to be the major determinants of the patient response to therapy and outcome. The primary aim of this study was to establish the correlation between these molecular mutations and the clinico-hematologic parameters as well as the prognostic outcome of the Indian acute myeloid leukemia (AML) patients. MATERIALS AND METHODS: This prospective study involved newly diagnosed nonpromyelocytic AML patients who had undergone complete diagnostic workup, including immunophenotyping, conventional cytogenetics and molecular analysis for NPM1 and FLT3-ITD mutation by reverse transcriptase polymerase chain reaction at presentation. RESULTS: Overall, the prevalence of NPM1 and FLT3-ITD mutations was found to be 14.4% and 10.8%, respectively. Among patients with normal karyotype, leukocytosis was significantly associated with NPM1+ group than the NPM1- group (P = 0.0019) and more severe degree of anemia was observed in the FLT3-ITD+ patients than the other groups (P = 0.025). No significant correlation was found in terms of age at presentation (P = 0.56), sex ratio (P = 0.467), median platelet count (P = 0.27), and blast percentage between NPM1+ and FLT3-ITD+ groups. Complete remission (CR) rates were better in the NPM1+/FLT3-ITD- group than the other three groups. Unlike most other studies, improved CR rates as well as disease-free survival were observed in the NPM-/FLT3-ITD- group than the FLT3-ITD+ groups although not reaching statistically significant levels. CONCLUSION: Some differences in the clinical behavior of the Indian AML patients in comparison to that of the West in the presence of NPM1 and FLT3-ITD suggests that comprehensive studies are required to confirm the definitive role of these mutations among AML patients, especially with normal karyotype.

Chronic myeloid leukemia with a rare fusion transcript, e19a2 BCR-ABL1: A report of three cases from India.

The µ-bcr breakpoint connects exon 19 of BCR with ABL giving rise to the e19a2 transcript corresponding to the p230 fusion protein (micro-BCR breakpoint) which is rarely seen in chronic myeloid leukemia (CML) patients. Here we report three patients with p230 fusion protein presenting with different clinical presentations and diagnosed as CML-CP. These patients received Imatinib (tyrosine kinase inhibitor-TKI) and are still in remission.

Does Indian Myelodysplastic Syndrome Have a Biology Different from That in the West ?

abstract.

C1236T polymorphism in MDR1 gene correlates with therapeutic response to imatinib mesylate in Indian patients with chronic myeloid leukaemia.

Patients with chronic myeloid leukaemia show an excellent response to treatment with imatinib. However, in some patients, the disease is resistant to imatinib. This resistance may be related to the presence of genetic variations on the drug's pharmacokinetics and metabolism. We therefore studied three polymorphisms (C1236T, G2677T and C3435T) in the human multidrug-resistance gene (MDR1) in 86 patients with chronic myeloid leukaemia treated with imatinib. Imatinib resistance was more frequent in patients with TT genotype at locus 1236 than in those with CT/CC genotypes (p=0.003). For the other two loci (G2677T and C3435T), resistance was seen to be higher for TT genotype when compared to GG/GT and CT/CC but it was not statistically significant (p=0.13 and p=0.099). In conclusion, determination of C1236T MDR1 genotype may help to predict response to imatinib therapy in patients with chronic myeloid leukaemia.

MTHFR Gene Polymorphisms and the Risk of Acute Lymphoblastic Leukemia in Adults and Children: A Case Control Study in India.

Genetic polymorphisms in the methylene tetrahydrofolate reductase (MTHFR) gene have been associated with the development of acute leukemias and various malignancies. The role of MTHFR polymorphism in the development of pediatric acute lymphoblastic leukemia (ALL) has been extensively studied among north Indians in various settings, yet its association with acute leukemias remains unresolved. To evaluate the relationship between functional MTHFR polymorphisms, C677T and A1298C and possible effect on risk of ALL in adults and children in North Indian population by comparing them with healthy controls. DNA was isolated from peripheral blood of 184 ALL patients (33 adults, 151 children) and 155 controls and analyzed by a PCR-restriction fragment length polymorphism assay. The frequency of MTHFR 677CT and 1298 AC genotypes were significantly lower among adult ALL cases when compared to the controls. We found a 1.74-fold reduced risk of ALL in individuals with 1298AC polymorphic variant and a 9.17-fold decreased risk of adult ALL. However, no statistically significant difference was evident between the above polymorphisms and susceptibility to ALL in children. Polymorphisms in the MTHFR gene possibly modulate risk of ALL in north Indian adults but not in children, although larger studies are needed.

Cytogenetic profile of Indian patients with de novo myelodysplastic syndromes.

BACKGROUND & OBJECTIVES: Myelodysplastic syndrome (MDS) is a clonal haematopoietic stem cell disorder characterized by ineffective haematopoiesis and leukaemia progression. Cytogenetic analysis has proven to be a mandatory part of the diagnosis of MDS as well as a major indicator for predicting clinical course and outcome. Studies on cytogenetics of MDS are reported mostly from the West and only a few are available from Asian countries. We report herein cytogenetic studies on 40 Indian patients with primary MDS to find out the occurrence and type of chromosome abnormalities and recurring defects. METHODS: Cytogenetic analysis was done using GTG banding and karyotyped according to the International System for Human Cytogenetic Nomenclature (ISCN). RESULTS: Of the 40 patients, 19 patients (47.5%) showed clonal karyotypic abnormalities with distribution as follows: 3 of 15 (20%) of refractory anaemia (RA), 4 of 7 (57%) of refractory anaemia with excess blasts-1 (RAEB-1), 4 of 6 (67%) of refractory anaemia with excess blasts 2 (RAEB-2), 2 of 3 (67%) of refractory anaemia with ring sideroblasts (RARS), 2 of 4 (50%) of refractory cytopenia with multilineage dysplasia (RCMD), none (0%) RCMD-ringed sideroblasts (RCMD-RS) and 4 patients with 5q syndrome. The frequent abnormalities observed in our study were -7, 5q-and trisomy 8. INTERPRETATION & CONCLUSIONS: Two rare chromosomal abnormalities (6q-, 3q-) were found with unknown prognostic significance. Hence, cytogenetic analysis may be incorporated in the routine diagnosis of MDS since there are racial differences in clinical pictures and the molecular events.

Haematological & molecular profile of acute myelogenous leukaemia in India.

BACKGROUND & OBJECTIVE: Recurrent balanced translocations are generally recognized to be a major parameter for prognostication in acute myeloid leukaemia (AML). The chromosomal translocation t(15;17) results in PML/RARalpha fusion gene, t(8;21) results in AML1/ETO fusion gene and Inv 16 generates CBFbeta/MYH11 fusion gene. Patients with these mutations have a good prognosis unlike abnormalities in chromosome 5 or 7 or FLT3 genes. Therefore, we screened the AmL patients for known specific genetic abnormalities that could lead to more definitive prognoses. METHODS: A total of 113 AML patients were evaluated at diagnosis based on routine morphology and cytochemistry and classified according to the WHO criteria. The distribution of AML subtypes was M1(1), M2(32), M3(57), M4(14), M5(1), M6(1) and seven cases where morphological subtype could not be classified. RT-PCR was performed to identify PML/RARalpha, AML1/ETO, CBFbeta/MYH11 and FLT3 nternal tandem duplication (ITD). RESULTS: Of the 57 patients with M3 subtype, 55 had the PML-RARalpha fusion transcript. The prevalence of bcr3 (short isoform) was higher (62%) than that of bcr1 (long isoform) (38%) and no correlation was found with age, sex or white blood cell count. FLT3 internal tandem duplication (ITD) mutations were more frequent in patients with APL than in other AML subtypes (17.5 vs. 8.9%), the frequency greater in patients with bcr3 isoform (70%) than in those with in bcr1 isoform (30%). Patients with FLT3/ ITD mutations had a significantly higher median white cell count than those without these mutations (55 x 10(9)/l vs. 6.3 x 10(9)/l P<0.001). More patients with FLT3/ITD mutations died early (53%) than those without these mutations (16%) (P<0.01). AML1-ETO fusion transcript was detected in 16 of 56 patients with no correlation with clinical or haematological parameters. INTERPRETATION & CONCLUSION: The results of the present study showed presence of bcr3 (short isoform) higher than bcr1 (long isoform). FLT3 internal tandem duplication (ITD) mutation was predominant in acute promyelocytic leukaemia patients with bcr3 isoform. Thus, patients with APL who have FLT3 mutation appear to have a poorer prognosis. Therefore, rapid identification of specific translocations at diagnosis is important for prognostic purposes and their detection should be incorporated into routine assessment.

Impact of FLT3 internal tandem duplications on Indian acute promyelocytic leukemia patients: prognostic implications.

Despite recent advances in the treatment of acute promyelocytic leukemia (APL), early mortality and relapses still occur. With the view to evaluate the role of FLT3 mutation in APL, 54 patients (median age 28 years, range11-57 years, male to female ratio 1.2:1, median TLC 8.4 x 10(9)/l, range 1-170 x 10(9)/l) were studied by reverse transcriptase-PCR. Forty-two patients (77%) achieved first remission (CR1). Ten (18.5%) of the 54 patients had internal tandem duplication of exons 11 and 12 of the FLT3 gene. The median TLC count was significantly higher in FLT3 positive cases (Median TLC 55.0 x 10(9)/l) as compared to FLT3 negative cases (Median TLC 6.8 x 10(9)/l) (p = 0.001). Induction CR was much lower (40%) in FLT3/ITD positive cases as compared to 86% of FLT3/ITD negative cases (p = 0.005). Early deaths too were significantly associated with FLT3/ITD positive cases (50 vs. 16% p = 0.033). The difference in the occurrence of bcr1 and bcr3 isoforms was not statistically significant between the two groups. The data suggest that the presence of FLT3/ITD in APL patients confers a poor prognosis.