OBJECTIVE: To investigate the expression of Wilms'tumor 1 () gene in patients with acute myeloid leukemia (AML), and to explore its application in predicting prognosis of AML in patients with wild or mutated nucleophosmin 1() and Fms-like tyrosine kinase 3-internal tandem duplication (). METHODS: One hundred and sixty-seven newly diagnosed AML patients(exclued M3 type) were enrolled in this study. The survival of patients were analyzed with Kaplan-Meier method. The clinical data, laboratory findings and the survival of patients were analyzed and compared between patients with high expression (high- group) and those with low expression (low- group), as well as among the patients with or wild type and mutants. RESULTS: The overall response rates (ORR) in high- and low- groups were 65.9% (83/126) and 95.1% (39/41), respectively (<0.01). Compared with the low- group, the high- group had lower 2-y overall survival (OS) rate (46.1% vs. 75.2%, <0.05) and 2-y disease free survival (DFS) rate (43.5% vs. 68.5%, <0.05). After induction chemotherapy, the patients with decreased gene expression ≥ 1log was associated with higher ORR and 2-y OS rate (all <0.05), but the advantage of 2-y DFS rate was not shown (>0.05). In patients with wild type, the high- group had inferior ORR and 2-y OS rate (all <0.05), while in the patients with wild type, the high- group had inferior ORR, 2-y OS rate and 2-y DFS rate (all <0.05). In patients with or FLT3 -ITD mutations, the expression had no significantly predicting values in treatment efficacy and survival (all >0.05). CONCLUSIONS gene overexpression indicated poor prognosis of AML patients; the patients with decreased gene expression ≥ 1 log after the first induction therapy show better prognosis than those with<1 log. The gene expression level at diagnosis can be used as an unfavorable prognostic factor for AML patients with or wild types.
Disease-Free Survival ; Gene Expression Profiling ; Humans ; Kaplan-Meier Estimate ; Leukemia, Myeloid, Acute ; diagnosis ; genetics ; mortality ; Mutation ; Nuclear Proteins ; genetics ; Prognosis ; WT1 Proteins ; genetics ; fms-Like Tyrosine Kinase 3 ; genetics

OBJECTIVETo correlate the clinical features of patients with acute myeloid leukemia (AML) with mutations of FLT3-ITD, NPM1, CEBPA, c-KIT, DNMT3A and ND4 genes as well as chromosomal aberrations.

METHODSSomatic mutations of aforementioned genes in 412 newly diagnosed AML patients were detected with PCR and direct sequencing. All patients were also subjected to R-banding chromosomal analysis. The results were correlated with the clinical features and prognosis of the patients.

RESULTSThe mutation rates of FLT3-ITD, NPM1, CEBPA, c-KIT, DNMT3A and ND4 were 9.0% (26/289), 19.1% (50/262), 18.9% (34/180), 3.4% (7/208), 6.6% (9/137) and 6.9% (4/58), respectively. Patients with poor prognosis based on genetic mutations had lower blood platelet count than those with intermediate and good prognosis (P=0.001 and P=0.001, respectively). None of the three groups attained median overall survival (OS) (P> 0.05). The complete remission (CR) was similar among the three groups (P> 0.05). For patients with different prognosis based on cytogenetic findings, white blood cell count in those with intermediate prognosis was higher than those with good and poor prognosis (P< 0.001 and P=0.004, respectively), while the blood platelet count of the intermediate group was higher than that of the group with good prognosis (P=0.018). No significant difference was found among the three groups in terms of hemoglobin level (P> 0.05). The group with poor prognosis has attained shorter OS compared with those with good and intermediate prognosis (P< 0.001 and P=0.003, respectively). However, the CR rate of the group with good prognosis was higher than that of the intermediate group (P=0.001). For the group with intermediate prognosis, presence of genetic mutations did not correlate with the clinic characteristics such as white blood cell count, blood platelet count, hemoglobin level, OS and CR rate (P> 0.05 for all comparisons).

CONCLUSIONGenetic mutations combined with cytogenetic analysis can facilitate the prognosis and personalized treatment for patients with AML.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Leukemia, Myeloid, Acute ; genetics ; mortality ; Male ; Middle Aged ; Mutation ; Prognosis ; Young Adult

OBJECTIVETo study WT1 gene expression in children with acute myeloid leukemia (AML) and its possible correlations to clinical outcomes.

METHODSBone marrow samples were collected from 45 children with AML (excluding acute promyelocytic leukemia, AML-M3) at different time points of AML treatment and follow-up. WT1 gene expression levels in bone marrow mononuclear cells were assayed by real-time fluorescence quantitative PCR. The correlation between WT1 expression and prognosis was retrospectively analyzed.

RESULTSThe WT1 expression level in AML children with bone marrow blast cell percentage of >60% was significantly higher than in those with bone marrow blast cell percentage of ≤ 60% (p<0.05). The lower WT1 expression level was documented in children with AML-M2 compared with in children with other non-M2 subtypes (p<0.05). WT1 expression level in patients in complete remission was significantly lower than that in patients at diagnosis or relapse (p<0.01). The 2-year disease-free survival (DFS) in patients with higher WT1 expression was significantly lower than in those with lower WT1 expression at the end of induction chemotherapy (p<0.05). The 2-year overall survival (OS) and DFS in patients with ≥1 log WT1 reduction range were significantly higher than those with <1 log reduction of WT1 expression level at the end of induction chemotherapy (p<0.05). WT1 expression levels tended to rise 2-3 months prior to bone marrow relapse.

CONCLUSIONSWT1 expression level is closely correlated prognosis in children with AML. Dynamic monitoring of WT1 expression level is of great clinical importance in terms of individualized management, prognosis evaluation and relapse prediction.

Adolescent ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Leukemia, Myeloid, Acute ; drug therapy ; genetics ; mortality ; Male ; Recurrence ; WT1 Proteins ; genetics

BACKGROUND: To the best of our knowledge, the association between pediatric AML and mitochondrial aberrations has not been studied. We investigated various mitochondrial aberrations in pediatric AML and evaluated their impact on clinical outcomes. METHODS: Sequencing, mitochondrial DNA (mtDNA) copy number determination, mtDNA 4,977-bp large deletion assessments, and gene scan analyses were performed on the bone marrow mononuclear cells of 55 pediatric AML patients and on the peripheral blood mononuclear cells of 55 normal controls. Changes in the mitochondrial mass, mitochondrial membrane potential, and intracellular reactive oxygen species (ROS) levels were also examined. RESULTS: mtDNA copy numbers were about two-fold higher in pediatric AML cells than in controls (P<0.0001). Furthermore, a close relationship was found between mtDNA copy number tertiles and the risk of pediatric AML. Intracellular ROS levels, mitochondrial mass, and mitochondrial membrane potentials were all elevated in pediatric AML. The frequency of the mtDNA 4,977-bp large deletion was significantly higher (P< 0.01) in pediatric AML cells, and pediatric AML patients harboring high amount of mtDNA 4,977-bp deletions showed shorter overall survival and event-free survival rates, albeit without statistical significance. CONCLUSIONS: The present findings demonstrate an association between mitochondrial genome alterations and the risk of pediatric AML.
Bone Marrow Cells/metabolism ; Case-Control Studies ; Child ; Cohort Studies ; DNA, Mitochondrial/chemistry/genetics/metabolism ; Female ; Flow Cytometry ; Gene Deletion ; Gene Dosage ; *Genome, Mitochondrial ; Humans ; Leukemia, Myeloid, Acute/genetics/mortality/*pathology ; Male ; Membrane Potential, Mitochondrial ; Minisatellite Repeats/genetics ; Odds Ratio ; Reactive Oxygen Species/metabolism ; Sequence Analysis, DNA ; Survival Rate

OBJECTIVETo study the relationship between loss of sex chromosomes and prognosis in children with acute myeloid leukemia (AML) M2 subtype.

METHODSAccording to cytogenetic characteristics, 106 children with AML were divided into three groups: patients with normal karyotype (Group A, n=26), patients with abnormal karyotype who had no loss of sex chromosomes (Group B, n=52), and patients with abnormal karyotype who had loss of sex chromosomes (Group C, n=28). Prognosis was compared between the three groups.

RESULTSThe 5-year event-free survival (EFS) rates of Groups A, B, and C were (38.9±11.2)%, (59.3±7.3)%, and (66.5±10.5)%, respectively; the EFS of Group C was significantly higher than that of Group A (P=0.035). The 5-year overall survival (OS) rates of Groups A, B, and C were (54.3±13.5)%, (68.1±7.7)%, and (77.9±9.8)%, respectively (P>0.05). The 5-year EFS of 58 patients with t(8;21) was (63.3±7.3)%, significantly higher than that of patients with normal karyotype (P=0.015). All the 28 cases in Group C had t(8;21), and their 5-year EFS was not significantly different from that of patients with t(8;21) in Group B (P>0.05).

CONCLUSIONSLoss of sex chromosomes is a favorable karyotype in children with AML M2 subtype and the patients in this group mostly have t(8;21). Why loss of sex chromosomes indicates a favorable prognosis is probably because it is accompanied by t(8;21) in the patients.

Adolescent ; Child ; Child, Preschool ; Chromosomes, Human, Pair 21 ; Chromosomes, Human, Pair 8 ; Female ; Humans ; Karyotype ; Leukemia, Myeloid, Acute ; genetics ; mortality ; Male ; Prognosis ; Sex Chromosome Aberrations ; Translocation, Genetic

OBJECTIVETo evaluate the frequency of the nucleophosmin (NPM1) gene and the CCAAT/enhancer binding protein α gene (CEBPA) through polymerase chain reaction (PCR) array in pediatric patients with cytogenetically normal acute myeloid leukemia (CN-AML) and explore the clinical significances of these mutations.

METHODBetween August 2009 and December 2012, 30 children (<16 years old) with newly diagnosed CN-AML were included. The clinical characteristics were analyzed in these patients. PCR combined with direct sequencing was used to detect NPM1, CEBPA gene mutations. All the data were statistically analyzed using SPSS17.0 software.

RESULTThe gene mutations were detected in each of the 30 patients. NPM1 mutation was positive in three patients (10%) with type A mutation, while CEBPA mutation was positive in two patients (6.7%) with double mutations (TAD, bZIP) . Besides, FLT3/ITD mutation was positive in three patients. Patients with NPM1 or FLT3/ITD had a significantly elevated diagnostic WBC count with a median diagnostic WBC count of 102.80×10(9)/L compared with 18.56×10(9)/L for the patients without mutations(t = 2.353, P = 0.043), as well as the marrow blast percentage (94.0% vs. 80.0%, t = 3.804, P = 0.002). The complete remission was achieved in all the 3 patients with NPM1 mutations and 2 patients with CEBPA mutations. All the patients with these mutations also achieved 2-year event-free survival (EFS) and 2-year overall survival (OS), while 2-year EFS and 2-year OS of the other patients were (40.1 ± 11.2)% and (51.8 ± 10.9)% (P = 0.044, 0.091, respectively).

CONCLUSIONNPM1 and CEBPA mutations may indicate a favorable prognosis in pediatric CN-AML.

Adolescent ; CCAAT-Enhancer-Binding Proteins ; genetics ; Child ; Child, Preschool ; DNA Mutational Analysis ; Disease-Free Survival ; Female ; Genotype ; Humans ; Infant ; Leukemia, Myeloid, Acute ; genetics ; mortality ; pathology ; Male ; Mutation ; Nuclear Proteins ; genetics ; Prognosis ; Retrospective Studies ; fms-Like Tyrosine Kinase 3 ; genetics

Acute myeloid leukemia (AML) is a rare type of childhood acute leukemia, which has a worse prognosis than childhood acute lymphoblastic leukemia. Over the past decade, significant progress has been made in the treatment of childhood AML and the 5-year event-free survival rate may be as high as 70% in developed countries. This survival improvement is largely attributable to risk-stratified treatments, therapies tailored to individual patients based on the biological characteristics of the disease, and continuously improving supportive care. An accurate diagnosis is the prerequisite for risk stratification, prognostic evaluation and therapeutic decision making. How to reduce early mortality and thus improve overall survival, how to implement appropriate supportive treatment to reduce treatment-associated complications, and how to reduce treatment-related mortality are the key to the improvement of therapies for childhood acute myeloid leukemia.
Child ; Humans ; Leukemia, Myeloid, Acute ; diagnosis ; drug therapy ; genetics ; mortality ; Leukemia, Promyelocytic, Acute ; drug therapy ; genetics

OBJECTIVETo explore the expression of BCL2L12 gene and its clinical significance for de novo acute myeloid leukemia (AML).

METHODSReal-time quantitative PCR (RQ-PCR) was employed to measure the expression of BCL2L12 gene in 134 patients with de novo AML. The results were correlated with clinical features of patients.

RESULTSBCL2L12 gene transcript was determined for 134 AML patients and 49 healthy controls, with the median levels measured 0.1029 (0.0119-26.4090) and 0.2677 (0.0173-1.2858), respectively. There was a significant difference in the strength of BCL2L12 gene expression between patients and normal controls (P < 0.01). Those with lower BCL2L12 expression levels had a higher FLT3-ITD mutation rate compared with those with higher levels (27% vs. 5%, P = 0.036). Relapsed or refractory AML patients had lower expression compared with newly diagnosed patients (0.0873 vs. 0.1359, P = 0.014). There was no difference in overall survival (OS) between patients with higher and lower expression levels. However, for AML patients with a normal karyotype, the OS for those with lower expression was significant shorter (P = 0.037).

CONCLUSIONDe novo AML patients have a lower level of BCL2L12 gene expression. AML patients with lower BCL2L12 expression have a higher FLT3-ITD mutation rate, and most of them are relapse or refractory patients. In addition, among patients with a normal karyotype, those with a lower BCL2L12 expression have a shorter OS. Therefore, expression of the BCL2L12 gene may be used as a prognostic marker for AML patients with a normal karyotype.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Gene Expression Regulation, Leukemic ; Humans ; Karyotyping ; Leukemia, Myeloid, Acute ; genetics ; mortality ; Male ; Middle Aged ; Muscle Proteins ; genetics ; Mutation ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; Survival Analysis ; Young Adult ; fms-Like Tyrosine Kinase 3 ; genetics

OBJECTIVETo explore clinical and experimental features of 28 cases of childhood acute myeloid leukemia (AML) with 11q23/MLL gene rearrangements.

METHODSKaryotypes of 234 cases of de novo childhood AML were analyzed using short-term culture of bone marrow cells and R-banding. The fusion transcripts involving MLL gene and partial tandem duplication of MLL (MLL-PTD) were detected by multiple reverse transcription polymerase chain reaction (RT-PCR) assay. Two cases with 11q23 translocation by karyotypic analysis but with negative result of multiple RT-PCR were studied with MLL-dual-color fluorescence in situ hybridization (D-FISH).

RESULTSR-banding karyotypic analysis has revealed 20 cases with 11q23 translocation (14 cases with M5, 4 cases with M4, 2 cases with M2), including 12 cases with t(9;11)(p22;q23), 3 cases with t(1;11)(q21;q23), 2 cases with t(6;11)(q27;q23), 1 case with t(11;19)(q23;p13), 1 with t(5;11)(q31;q23), and 1 with t(X;11)(q24;q23). Eighteen cases with 11q23 translocation having fusion transcripts involving MLL genes were confirmed with multiple RT-PCR; 2 cases showed negative results, but they were confirmed to have MLL rearrangements by D-FISH. MLL-PTD was also detected in 8 cases (4 cases M5, 2 cases M4, M2 and M6, one case each) from the other childhood AML cases. The total incidence of 11q23/MLL gene rearrangements was 11.97% (28/234), and most of patients(85.7%, 24/28) were M4/M5. The complete remission (CR) rate after treatment for the 28 cases with MLL rearrangements was 53.8%, the difference was significant by statistics (P< 0.05) compared with 90.5% for the control group (M4/M5 childhood AML with other karyotypic abnormalities or normal karyotype). Of them, 2 cases receiving intensive chemotherapy survived for 81 and 66 months, respectively, 4 cases receiving allogeneic stem cell transplantation survived for 21, 20, 16 and 11 months, respectively, and are still alive with CR. The medium survival (MS) time for 28 cases with 11q23/MLL rearrangements was 11 months, whereas the MS for control group was 15 months. The difference was not statistically significant(P> 0.05).

CONCLUSIONThe 11q23/MLL rearrangements is highly correlated with the occurrence of monocytic leukemia (M4 and M5). The 11q23 translocation and MLL-PTD are mutually exclusive, though both are indicative of poor prognosis. Intensive chemotherapy and allogeneic stem cell transplantation may ameliorate the clinical outcome. Multiple RT-PCR combined with karyotypic analysis and D-FISH are useful for screening the 11q23/MLL rearrangements in childhood AML.

Adolescent ; Child ; Child, Preschool ; Chromosomes, Human, Pair 11 ; Female ; Humans ; Immunophenotyping ; In Situ Hybridization, Fluorescence ; Infant ; Karyotyping ; Leukemia, Myeloid, Acute ; diagnosis ; drug therapy ; genetics ; mortality ; Male ; Myeloid-Lymphoid Leukemia Protein ; genetics ; Remission Induction ; Translocation, Genetic ; Treatment Outcome

UNLABELLEDOBJECTIVE To study the clinical and biological characteristics and prognosis of t(8;21)/AML1-ETO-positive childhood acute myeloid leukemia (AML).

METHODSThe clinical data of 55 children who were diagnosed as t (8; 21)/AML1-ETO-positive AML were retrospectively studied. Event-free survival (EFS), disease-free survival (DFS), and overall survival (OS) rates were estimated by the Kaplan-Meier method. Prognostic factors were evaluated by COX regression analysis software.

RESULTSOf the 55 patients, 4 patients gave up treatment after the diagnosis was confirmed and 4 patients were lost to follow-up after the first chemotherapy course. The remaining 47 patients received a double-induction therapy. The total complete remission (CR) rate was 71% and 94% after the first and second chemotherapy course, respectively. The disease was relapsed in 10 patients (21%). The 5-year EFS, DFS and OS rates were (56.1 ± 7.9)%, (59.8 ± 8.1)%, and (72.0 ± 8.1)%, respectively. Multivariate analysis showed that age was an independent risk factor for the long-term prognosis. The older children had a greater risk of experiencing an accident or death (P<0.05). The 5-year OS rate in 27 patients with regular consolidation chemotherapy was significantly higher than 13 patients with irregular chemotherapy after CRz [(47.5 ± 17.1)% vs (38.9 ± 17.3)%; P<0.01].

CONCLUSIONSChildhood t(8;21)/AML1-ETO-positive AML is a highly heterogeneous disease, with a high CR rate and a good long-term prognosis. Age is one of the important factors affecting the long-term therapeutic effect. Regular consolidation chemotherapy applied after CR usually is helpful.

Adolescent ; Bone Marrow Examination ; Child ; Child, Preschool ; Chromosomes, Human, Pair 21 ; Chromosomes, Human, Pair 8 ; Core Binding Factor Alpha 2 Subunit ; analysis ; Female ; Humans ; Leukemia, Myeloid, Acute ; genetics ; mortality ; Male ; Oncogene Proteins, Fusion ; analysis ; Prognosis ; RUNX1 Translocation Partner 1 Protein ; Translocation, Genetic