FHIT Gene Expression in Acute Lymphoblastic Leukemia and its Clinical Significance

Background: To investigate the expression of the fragile histidine triad (FHIT) gene in acute lymphoblastic leukemia and its clinical significance. Materials and Methods: The level of expressed FHIT mRNA in peripheral blood from 50 patients with acute lymphoblastic leukemia (ALL) and in 50 peripheral blood samples from healthy volunteers was measured via RT-PCR. Correlation analyses between FHIT gene expression and clinical characteristics (gender, age, white blood count, immunophenotype of acute lymphoblastic leukemia and percentage of blast cells) of the patients were performed. Results: The FHIT gene was expressed at 2.49±7.37 of ALL patients against 14.4±17.9 in the healthy volunteers. The difference in the expression levels between ALL patients and healthy volunteers was statistically significant. The rate of gene expression did not significantly vary with immunophenotype subtypes. Gene expression was also found to be correlated with increase of total leukocyte and decrease in platelets, but not with age, gender, immunophenotyping or percentage of blast cells. Conclusions: FHIT gene expression is low in acute lymphoblastic leukemia and could be a useful marker to monitor minimal residual disease. This gene is also a candidate target for the immunotherapy of acute lymphoblastic leukemia.     

Childhood Acute Leukemia in West Bengal,India with an Emphasis on Uncommon Clinical Features

Leukemias are the commonest childhood malignancy in West Bengal. This study was undertaken on 75children at NRS Medical College, West Bengal to determine the distribution of signs and symptoms of leukemiaand to identify unusual clinical features. After obtaining clinical history, physical examination, hematologicaland radiological investigations were performed. Acute lymphoblastic leukaemia (ALL, 72%) was the commonestfollowed by acute myeloid leukaemia (AML, 18.7%). Common symptoms and signs were fever (85.3%), pallor(64%), hepatomegaly (72%), splenomegaly (60%) and lymphadenopathy (50.7%). The uncommon signs andsymptoms were abdominal pain (9.3%), joint pain (9.3%), hematemesis and malena (8%), diarrhea (5.33%),proptosis (2 cases), dysphagia, mediastinal mass and parotid swelling (1 case each). Uncommon clinicalpresentations lead to delay in diagnosis in some cases. Awareness of uncommon signs and symptoms of childhoodleukemia together with laboratory tests may help in earlier diagnosis and proper management of the patients.     

Prognostically Significant Fusion Oncogenes in Pakistani Patients with Adult Acute Lymphoblastic Leukemia and their Association with Disease Biology and Outcome

Background and objectives: Chromosomal abnormalities play an important role in genesis of acute lymphoblastic leukemia (ALL) and have prognostic implications. Five major risk stratifying fusion genes in ALL are BCR-ABL, MLL-AF4, ETV6-RUNX11, E2A-PBX1 and SIL-TAL1. This work aimed to detect common chromosomal translocations and associated fusion oncogenes in adult ALL patients and study their relationship with clinical features and treatment outcome. Methods: We studied fusion oncogenes in 104 adult ALL patients using RT-PCR and interphase-FISH at diagnosis and their association with clinical characteristics and treatment outcome. Results: Five most common fusion genes i.e. BCR-ABL (t 9; 22), TCF3-PBX1 (t 1; 19), ETV6-RUNX1 (t 12; 21), MLL-AF4 (t 4; 11) and SIL-TAL1 (Del 1p32) were found in 82/104 (79%) patients. TCF3-PBX1 fusion gene was associated with lymphadenopathy, SIL-TAL positive patients had frequent organomegaly and usually presented with a platelets count of less than 50 x109/l. Survival of patients with fusion gene ETV6-RUNX1 was better when compared to patients harboring other genes. MLL-AF4 and BCR-ABL positivity characterized a subset of adult ALL patients with aggressive clinical behaviour and a poor outcome. Conclusions: This is the first study from Pakistan which investigated the frequency of 5 fusion oncogenes in adult ALL patients, and their association with clinical features, treatment response and outcome. Frequencies of some of the oncogenes weredifferent from those reported elsewhere and they appear to be associated with distinct clinical characteristics and treatment outcome. This information will help in the prognostic stratification and risk adapted management of adult ALL patients.     

Comparison of Univariate and Multivariate Gene Set Analysisin Acute Lymphoblastic Leukemia

Background: Gene set analysis (GSA) incorporates biological with statistical knowledge to identify gene setswhich are differentially expressed that between two or more phenotypes. Materials and Methods: In this papergene sets differentially expressed between acute lymphoblastic leukaemia (ALL) with BCR-ABL and those withno observed cytogenetic abnormalities were determined by GSA methods. The BCR-ABL is an abnormal genefound in some people with ALL. Results: The results of two GSAs showed that the Category test identified 30gene sets differentially expressed between two phenotypes, while the Hotelling’s T2 could discover just 19 genesets. On the other hand, assessment of common genes among significant gene sets showed that there were highagreement between the results of GSA and the findings of biologists. In addition, the performance of these methodswas compared by simulated and ALL data. Conclusions: The results on simulated data indicated decrease inthe type I error rate and increase the power in multivariate (Hotelling’s T2) test as increasing the correlationbetween gene pairs in contrast to the univariate (Category) test.     

Philadelphia Chromosome-positive Chronic Myelogenous Leukemia with Deleted Fusion of BCR and ABL Genes

In the great majority of patients with chronic myelogenous leukemia (CML) the reciprocal translocation between chromosomes 9 and 22, t(9;22)(q34;q11), resulting in the Philadelphia (Ph) chromosome produces fusion DNA sequences consisting of the 5′ part of the major breakpoint cluster region-1 (M-BCR-1) and the ABL protooncogene which encodes for the P210^BCR-ABL phosphoprotein with tyrosine kinase activity implicated in the pathogenesis of CML. Molecular analysis was performed on 25 patients with Ph-positive CML using 2 breakpoint cluster region (bcr) probes within the M-BCR-1 DNA sequences, and two of them did not contain either detectable rearranged DNA homologous to the 5′ side bcr probe or ABL-related fusion mRNA. The chromosomal in situ hybridization technique revealed that these two Ph-positive CML cases did not carry DNAs homologous to the 5′bcr or ABL probes on the Ph chromosome. Furthermore, one of the two Ph-positive CML cases did not show either rearranged DNA or regions homologous to the 3′bcr probe on a 9q+ chromosome, while the other CML case showed a rearrangement detected by the 3′bcr probe and transposition of the 3′bcr homologous to the 9q+ chromosome. Thus, the possibility is raised that the BCR/ABL fusion DNA has been deleted in rare CML cases, and that the deletion possibly occurred in a stepwise manner following the formation of the Ph chromosome at any stage of the disease.     

New Haplotypes of the ATP Synthase Subunit 6 Gene of Mitochondrial DNA are Associated with Acute Lymphoblastic Leukemia in Saudi Arabia

Background: Acute lymphoblastic leukemia (ALL) is the most common cancer diagnosed in children andrepresents approximately 25% of cancer diagnoses among those younger than 15 years of age. Aim and Objectives:This study investigated substitutions in the ATP synthase subunit 6 gene of mitochondrial DNA (mtDNA) asa potential diagnostic biomarker for early detection and diagnosis of acute lymphoblastic leukemia. Basedon mtDNA from 23 subjects diagnosed with acute lymphoblastic leukemia, approximately 465 bp of the ATPsynthase subunit 6 gene were amplified and sequenced. Results: The sequencing revealed thirty-one mutationsat 14 locations in ATP synthase subunit 6 of mtDNA in the ALL subjects. All were identified as single nucleotidepolymorphisms (SNPs) with a homoplasmic pattern. The mutations were distributed between males and females.Novel haplotypes were identified in this investigation: haplotype (G) was recorded in 34% in diagnosed subjects;the second haplotype was (C) with frequency of 13% in ALL subjects. Neither of these were observed in controlsamples. Conclusions: These haplotypes were identified for the first time in acute lymphoblastic leukemia patients.Five mutations able to change amino acid synthesis for the ATP synthase subunit 6 were associated with acutelymphoblastic leukemia. This investigation could be used to provide an overview of incidence frequency of acutelyphoblastic leukemia (ALL) in Saudi patients based on molecular events.     

BCR-ABL: An Anti-Apoptosis Gene in Chronic Myelogenous Leukemia

The expression of ber-abl in chronic myelogenous leukemia leads to a large increase in the generation of mature myeloid cells. The key biochemical alteration in this disease is am increased Abl kinase activity. This up-regulation in activity is mediated through the binding of a portion of the Ber molecule to the SH2 regulatory domain of the Ab1 protein. One effect of this alteration is a marked increase in resistance to drug induced cell death by apoptosis. The resistance can be overcome with the use of appropriate antisense oligonucleotides to the bcr-abl gene. The role and contribution of apoptosis to the development of the disease and the prospect of using antisense oligonucleotides as therapeutic agents is discussed.     

Risk Factors of Daunorubicine Induced Early Cardiotoxicity in Childhood Acute Lymphoblastic Leukemia: A Retrospective Study

Background: Daunorubicine, a type of anthracycline, is a drug commonly used in cancer chemotherapy that increases survival rate but consequently compromises with cardiovascular outcomes in some patients. Thus, preventing the early progression of cardiotoxicity is important to improve the treatment outcome in childhood acute lymhoblastic leukemia (ALL). Objective: The present study aimed to identify the risk factors in anthracycline-induced early cardiotoxicity in childhood ALL. Methods: This retrospective study was conducted by observing ALL-diagnosed children from 2014 to 2019 in Dr. Soetomo General Hospital. There were 49 patients who met the inclusion criteria and were treated with chemotherapy using Indonesian Childhood ALL Protocol 2013. Echocardiography was performed by pediatric cardiologists to compare before and at any given time after anthracycline therapy. Early cardiotoxicity was defined as a decline of left ventricle ejection fraction (LVEF) greater than 10% with a final LVEF < 53% during the first year of anthracycline administration.  Risk factors such as sex, age, risk stratification group, and cumulative dose were identified by using multiple logistic regression. Diagnostic performance of cumulative anthracycline dose was evaluated by receiver operating characteristic (ROC) curve. Results: Early anthracycline-induced cardiotoxicity was observed in 5 out of 49 patients. The median cumulative dose of anthracycline was 143.69±72.68 mg/m2. Thirty-three patients experienced a decreasing LVEF. The factors associated with early cardiomyopathy were age of ≥ 4 years (PR= 1.128; 95% CI: 1.015-1.254; p= 0.001), high risk group (PR= 1.135; 95% CI: 1.016-1.269; p= 0.001), and cumulative dose of ≥120 mg / m2 (CI= 1.161; 95% CI:1.019-1.332). Conclusion: Age of ≥ 4 years, risk group, and cumulative dose of ≥120 mg/m2 are significant risk factors for early cardiomyopathy in childhood ALL.     

Mutation Screening and Association Study of the Folylpolyglutamate Synthetase (FPGS) Gene with Susceptibility to Childhood Acute Lymphoblastic Leukemia

Background: Folylpolyglutamate synthetase (FPGS), an important enzyme in the folate metabolic pathway,plays a central role in intracellular accumulation of folate and antifolate in several mammalian cell types. Loss ofFPGS activity results in decreased cellular levels of antifolates and consequently to polyglutamatable antifolatesin acute lymphoblastic leukemia (ALL). Materials and Methods: During May 1997 and December 2003, 134children diagnosed with ALL were recruited from one hospital in Thailand. We performed a mutation analysis inthe coding regions of the FPGS gene and the association between single nucleotide polymorphisms (SNPs) withinFPGS in a case-control sample of childhood ALL patients. Mutation screening was conducted by polymerasechain reaction-single strand conformation polymorphism (PCR-SSCP) and subsequently with direct sequencing(n=72). Association analysis between common FPGS variants and ALL risk was done in 98 childhood ALL casesand 95 healthy volunteers recruited as controls. Results: Seven SNPs in the FPGS coding region were identifiedby mutation analysis, 3 of which (IVS13+55C>T, g.1297T>G, and g.1508C>T) were recognized as novel SNPs.Association analysis revealed 3 of 6 SNPs to confer significant increase in ALL risk these being rs7039798 (p=0.014, OR=2.14), rs1544105 (p=0.010, OR= 2.24), and rs10106 (p=0.026, OR= 1.99). Conclusions: These findingssuggested that common genetic polymorphisms in the FPGS coding region including rs7039789, rs1544105, andrs10106 are significantly associated with increased ALL risk in Thai children.     

Five Most Common Prognostically Important FusionOncogenes are Detected in the Majority of Pakistani Pediatric Acute Lymphoblastic Leukemia Patients and are Strongly Associated with Disease Biology and Treatment Outcome

Background and Objectives: Acute lymphoblastic leukemia (ALL) is a complex genetic disease involvingmany fusion oncogenes (FO) having prognostic significance. The frequency of various FO can vary in differentethnic groups, with important implications for prognosis, drug selection and treatment outcome. Method: Westudied fusion oncogenes in 101 pediatric ALL patients using interphase FISH and RT-PCR, and their associationswith clinical features and treatment outcome. Results: Five most common fusion genes i.e. BCR-ABL t (22;9), TCF3-PBX1 (t 1; 19), ETV6-RUNX1 (t 12; 21), MLL-AF4 (t 4; 11) and SIL-TAL1 (del 1p32) were foundin 89/101 (88.1%) patients. Frequency of BCR-ABL was 44.5% (45/101). BCR-ABL positive patients had asignificantly lower survival (43.7±4.24 weeks) and higher white cell count as compared to others, except patientswith MLL-AF4. The highest relapse-free survival was documented with ETV6-RUNX1 (14.2 months) followedclosely by those cases in which no gene was detected (13.100). RFS with BCR-ABL, MLL-AF4, TCF3-PBX1and SIL-TAL1 was less than 10 months (8.0, 3.6, 5.5 and 8.1 months, respectively). Conclusions: This is the firststudy from Pakistan correlating molecular markers with disease biology and treatment outcome in pediatricALL. It revealed the highest reported frequency of BCR-ABL FO in pediatric ALL, associated with poor overallsurvival. Our data indicate an immediate need for incorporation of tyrosine kinase inhibitors in the treatmentof BCR-ABL+ pediatric ALL in this population and the development of facilities for stem cell transplantation.     

Activation of Bcr-abl Fusion Gene and Ras Oncogenes in Chronic Myelogenous Leukemia

We attempted to detect the bcr-abl fusion gene and ras gene family in CML by the in vitro focus forming assay and the tumorigenicity assay. Eight of 14 chronic phase and both of two blastic phase cases showed transforming activity in the tumorigenicity assay. However, only one chronic phase sample was positive in the in vitro focus forming assay. Among these 10 transformants, we found N-ras activation in one chronic phase, and K-ras activation in another chronic phase case. The bcr-abl fusion gene was activated in one chronic phase and all of the blastic phase cases by the tumorigenicity assay. The present result showed that the bcr-abl fusion gene transfected N1H3T3 cells formed tumors in nude mice in contrast to the in vitro focus forming assay. The bcr-abl fusion gene may play important roles in the progression as well as the pathogenesis of CML.     

Bone Mineral Density in Survivors of Childhood Acute Lymphoblastic Leukemia

Background: The objective of this study was to evaluate bone mineral density (BMD) after completion of treatment for childhood acute lymphoblastic leukemia (ALL). Methods: In this cross-sectional study, 103 survivors of ALL aged 13.5 ± 0.45 who completed their treatment at least one year earlier were enrolled. Among these, 49.5% and 51.5% received chemotherapy alone and chemotherapy plus cranial radiotherapy, respectively. Bone mineral content, BMD, and bone mineral apparent density in the lumbar spine (LS), femoral neck (FN) and forearm were assessed using dual-energy X-ray absorptiometry (DEXA). BMD Z-scores were classified according to International Society for Clinical Densitometry (ISCD) criteria. Results: The mean BMD Z-scores ± SD forLS, FN and forearm were -1.60 ± 0.12, -1.21 ± 0.9 and -2.43 ± 0.14 respectively with significant differences (P<0.001). Considering the lowest BMD Z-score in LS and FN areas (at any site) and according to the ISCD classification, 62.1%, 33% and 4.9% of the patients had normal BMD, low BMD and osteoporosis, respectively. Also, 8.7% of patients had developed fractures after completion of the treatment period, 4.9% having BMD Z-Scores Conclusions: ALL patients are at risk for low BMD and fracture. Therefore, applying DEXA scanning is recommended after completion of therapy for prevention of BMD reduction and osteoporosis.     

Risk of Acute Lymphoblastic Leukemia: Results of a Case-Control Study

Background: Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. Differentenvironmental factors might be effective in the occurrence of this malignancy during childhood. The aim of this studywas to find environmental risk factors in childhood ALL in Hamadan, Iran. Methods: This case-control study wasdone in 2015-2018 on 125 children younger than 15 years of age suffering from ALL. Patients were matched with130 controls with respect to age, gender, and residence location. The identification of risk factors for ALL was soughtbased on the comparison of studied variables between case and control individuals. Results: A statistically significantincreased risk for ALL was found with regard to type of delivery (OR: 0.43, 95% CI: 0.20 - 0.92, p˂0.02), childcare(OR: 4.58, 95% CI: 0.95 - 22.20, p˂0.04), birth weight (OR: 1.44, 95% CI: 1.53 - 2.21, p˂0.006), father’s educationlevel (OR: 2.67, 95% CI: 1.10 - 6.45, p˂0.02), and father’s job (OR: 0.2 95% CI: 0.08 - 0.51, p˂0.001). Also observedwere increased odds for ALL regarding male gender, mother’s high education level, mother’s freelance job, and mediumor high family income. No association with ALL incidence was observed for age, gender, breastfeeding, mother’s ageat pregnancy, malignancy in first- or second-degree relatives, or mother’s use of hair dye during pregnancy (p> 0.05).Conclusion: This study showed that father’s education level, father’s job, delivery type, birth weight, and childcarecan play a role in the incidence of childhood ALL.     

γ-Catenin-Dependent Signals Maintain BCR-ABL1+ B Cell Acute Lymphoblastic Leukemia

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急性髓系白血病患者HOX11基因的表达及意义

目的 探讨HOX11基因在急性髓系白血病(acute myeloid leukemia,AML)中的表达及对预后的影响,为个体化治疗提供依据.方法 应用多重巢式RT-PCR方法对73例初诊AML患者的融合基因进行检测,对HOX11基因表达阳性和阴性的患者进行标准治疗后的疗效进行分析.结果 在预后良好组、预后中等组及预后不良组AML患者的标准治疗中,HOX11基因阳性表达患者的第一疗程完全缓解率(complete remission rate)并不高于阴性表达的患者(P＞0.05),而复发或死亡率(relapse or mortality rate)与HOX11基因阴性表达的患者比较差异有统计学意义(P＜0.05).结论 HOX11基因的表达可能影响AML患者的预后.     

急性淋巴细胞白血病患儿MTHFR基因多态性与大剂量甲氨蝶呤毒副反应的相关性

目的:探讨亚甲基四氢叶酸还原酶(MTHFR)基因677位点多态性与急性淋巴细胞白血病(ALL)患儿使用大剂量甲氨蝶呤(HDMTX)化疗后毒副反应的相关性.方法:收集46例完全缓解并接受HDMTX治疗的ALL患儿外周血,提取基因组DNA,用PCR-芯片杂交法检测MTHFR基因C677T多态性.应用荧光偏振免疫法(FPIA)测定24小时、48小时血浆MTⅨ浓度.按照国立癌症研究所常规毒性判定标准(NCI-CTC)对患儿HDMTX化疗毒副反应进行评价.对MTHFR677位点基因多态性与HDMTX毒副反应、48小时血浆MTX浓度的相关性进行分析.结果:HDMTX化疗相关毒副反应以骨髓抑制及肝毒性为主.C677T各基因型的48h MTX血药浓度及发生各类化疗毒副反应差异无统计学意义.结论:影响MTX的体内代谢及毒副反应的因素复杂,MTHFR C677T基因多态性尚不能作为HDMTX体内排泄及毒副反应的有效预测性指标.