Classification systems for acute and chronic leukaemias

Honokiol induces apoptosis and autophagy in dexamethasone-resistant T-acute lymphoblastic leukemia CEM-C1 cells

Objective: To study whether and, if so, how honokiol overcome dexamethasone resistance in DEX-resistant CEM-C1 cells. Methods: We investigated the effect of honokiol (0-20 µM) on cell proliferation, cell cycle, cell apoptosis and autophagy in DEX-resistant CEM-C1 cells and DEX-sensitive CEM-C7 cells. We also determined the role of c-Myc protein and mRNA in the occurrence of T-ALL associated dexamethasone resistance western blot and reverse transcription-qPCR (RT-qPCR) analysis. Results: Cell Counting Kit (CCK)-8 assay shows that DEX-resistant CEM-C1 cell lines were highly resistant to dexamethasone with IC50 of 364.1 ± 29.5 µM for 48 h treatment. However, upon treatment with dexamethasone in combination with 1.5 µM of honokiol for 48 h, the IC50 of CEM-C1 cells significantly decreased to 126.2 ± 12.3 µM, and the reversal fold was 2.88. Conversely, the IC50 of CEM-C7 cells was not changed combination of dexamethasone and honokiol as compared to that of CEM-C7 cells treated with dexamethasone alone. It has been shown that honokiol induced T-ALL cell growth inhibition by apoptosis and autophagy via downregulating cell cycle-regulated proteins (Cyclin E, CDK4, and Cyclin D1) and anti-apoptotic proteins BCL-2 and upregulating pro-apoptotic proteins Bax and led to PARP cleavage. Honokiol may overcome dexamethasone resistance in DEX-resistant CEM-C1 cell lines via the suppression of c-Myc mRNA expression. Conclusion: The combination of honokiol and DEX were better than DEX alone in DEX-resistant CEM-C1 cell lines. Honokiol may regulate T-ALL-related dexamethasone resistance by affecting c-Myc.

The Evolving Landscape of Flowcytometric Minimal Residual Disease Monitoring in B-Cell Precursor Acute Lymphoblastic Leukemia

Detection of minimal residual disease (MRD) is a major independent prognostic marker in the clinical management of pediatric and adult B-cell precursor Acute Lymphoblastic Leukemia (BCP-ALL), and risk stratification nowadays heavily relies on MRD diagnostics. MRD can be detected using flow cytometry based on aberrant expression of markers (antigens) during malignant B-cell maturation. Recent advances highlight the significance of novel markers (e.g., CD58, CD81, CD304, CD73, CD66c, and CD123), improving MRD identification. Second and next-generation flow cytometry, such as the EuroFlow consortium's eight-color protocol, can achieve sensitivities down to 10-5 (comparable with the PCR-based method) if sufficient cells are acquired. The introduction of targeted therapies (especially those targeting CD19, such as blinatumomab or CAR-T19) introduces several challenges for flow cytometric MRD analysis, such as the occurrence of CD19-negative relapses. Therefore, innovative flow cytometry panels, including alternative B-cell markers (e.g., CD22 and CD24), have been designed. (Semi-)automated MRD assessment, employing machine learning algorithms and clustering tools, shows promise but does not yet allow robust and sensitive automated analysis of MRD. Future directions involve integrating artificial intelligence, further automation, and exploring multicolor spectral flow cytometry to standardize MRD assessment and enhance diagnostic and prognostic robustness of MRD diagnostics in BCP-ALL.

Childhood Acute Lymphoblastic Leukemia: Results of the Randomized Acute Lymphoblastic Leukemia Intercontinental-Berlin-Frankfurt-Münster 2009 Trial

PURPOSE

The International Berlin-Frankfurt-Münster (BFM) study group conducted a study on pediatric acute lymphoblastic leukemia (ALL). Minimal residual disease (MRD) was assessed using flow cytometry (FCM), and the impact of early intensification and methotrexate (MTX) dose on survival was evaluated.

PATIENTS AND METHODS

We included 6,187 patients younger than 19 years. MRD by FCM refined the risk group definition previously used in the ALL intercontinental-BFM 2002 study on the basis of age, WBC count, unfavorable genetic aberrations, and treatment response measured morphologically. Patients at intermediate risk (IR) and high risk (HR) were randomly assigned to protocol augmented protocol I phase B (IB) versus IB regimen. MTX doses of 2 versus 5 g/m² every 2 weeks, four times, were evaluated in precursor B-cell-ALL (pcB-ALL) IR.

RESULTS

The 5-year event-free survival (EFS ± SE) and overall survival (OS ± SE) rates were 75.2% ± 0.6% and 82.6% ± 0.5%, respectively. Their values in risk groups were standard risk (n = 624), 90.7% ± 1.4% and 94.7% ± 1.1%; IR (n = 4,111), 77.9% ± 0.7% and 85.7% ± 0.6%; and HR (n = 1,452), 60.8% ± 1.5% and 68.4% ± 1.4%, respectively. MRD by FCM was available in 82.6% of cases. The 5-year EFS rates in patients randomly assigned to protocol IB (n = 1,669) and augmented IB (n = 1,620) were 73.6% ± 1.2% and 72.8% ± 1.2%, respectively (P = .55), while those in patients receiving MTX doses of 2 g/m² (n = 1,056) and MTX 5 g/m² (n = 1,027) were 78.8% ± 1.4% and 78.9% ± 1.4%, respectively (P = .84).

CONCLUSION

The MRDs were successfully assessed using FCM. An MTX dose of 2 g/m² was effective in preventing relapse in non-HR pcB-ALL. Augmented IB showed no advantages over the standard IB.

Analysis of the differential expression and prognostic relationship of DEGs in AML based on TCGA database

BACKGROUND

Acute myeloid leukemia (AML) is a common and lethal hematological malignant hyperplastic disease originating from hematopoietic stem cells. The purpose of this study is to obtain the key differentially expressed gene (DEG) related to the survival of AML by The Cancer Genome Atlas (TCGA) database and to verify these genes by a clinical follow-up investigation, in order to identify valuable predictive and prognostic biomarkers for early diagnosis of AML and predict the survival rates.

METHODS

The RNA sequencing (RNA-Seq) data and clinical information of TCGA-LAML were downloaded from the TCGA database. After that we (1) screened the survival-related DEGs by Cox regression analysis, (2) selected the cytogenetics risk-related DEGs by DESeq2 R package, and (3) filtrated the genes in the top10 pathways of up-regulated and down-regulated of Normalization Enrichment Score (NES) by Gene Set Enrichment Analysis (GSEA). Finally, we focused the intersectional genes of above three parts as the key gene of the present study. The following Multivariate.

Immunotherapy approaches for hematological cancers

Hematological cancers such as leukemia, lymphoma, and multiple myeloma have traditionally been treated with chemo and radiotherapy approaches. Introduction of immunotherapies for treatment of these diseases has led to patient remissions that would not have been possible with traditional approaches. In this critical review we identify main disease characteristics, symptoms, and current treatment options. Five common immunotherapies, namely checkpoint inhibitors, vaccines, cell-based therapies, antibodies, and oncolytic viruses, are described, and their applications in hematological cancers are critically discussed.

Commonly Assessed Markers in Childhood BCP-ALL Diagnostic Panels and Their Association with Genetic Aberrations and Outcome Prediction

Immunophenotypic characterization of leukemic cells with the use of flow cytometry (FC) is a fundamental tool in acute lymphoblastic leukemia (ALL) diagnostics. A variety of genetic aberrations underlie specific B-cell precursor ALL (BCP-ALL) subtypes and their identification is of great importance for risk group stratification. These aberrations include: ETV6::RUNX1 fusion gene, Philadelphia chromosome (BCR::ABL1 fusion gene), rearrangements of the KMT2A, TCF3::PBX1 fusion gene and changes in chromosome number (hyperdiploidy and hypodiploidy). Diagnostic panels for BCP-ALL usually include B-cell lineage specific antigens: CD19, CD10, CD20, maturation stage markers: CD34, CD10, CD38, TdT, IgM and other markers useful for possible genetic subtype indication. Some genetic features of leukemic cells (blasts) are associated with expression of certain antigens. This review comprehensively summarizes all known research data on genotype-immunophenotype correlations in BCP-ALL. In some cases, single molecules are predictive of particular genetic subtypes, i.e., NG2 with KMT2A gene rearrangements or CD123 with hyperdiploidy. However, much more information on possible genotype or prognosis can be obtained with wider (≥8-color) panels. In several studies, a quantitative antigen expression scale and advanced statistical analyses were used to further increase the specificity and sensitivity of genotype/immunophenotype correlation detection. Fast detection of possible genotype/immunophenotype correlations makes multicolor flow cytometry an essential tool for initial leukemia diagnostics and stratification.

Mechanisms of Immune Evasion in Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) results from a clonal expansion of abnormal lymphoid progenitors of B cell (BCP-ALL) or T cell (T-ALL) origin that invade bone marrow, peripheral blood, and extramedullary sites. Leukemic cells, apart from their oncogene-driven ability to proliferate and avoid differentiation, also change the phenotype and function of innate and adaptive immune cells, leading to escape from the immune surveillance. In this review, we provide an overview of the genetic heterogeneity and treatment of BCP- and T-ALL. We outline the interactions of leukemic cells in the bone marrow microenvironment, mainly with mesenchymal stem cells and immune cells. We describe the mechanisms by which ALL cells escape from immune recognition and elimination by the immune system. We focus on the alterations in ALL cells, such as overexpression of ligands for various inhibitory receptors, including anti-phagocytic receptors on macrophages, NK cell inhibitory receptors, as well as T cell immune checkpoints. In addition, we describe how developing leukemia shapes the bone marrow microenvironment and alters the function of immune cells. Finally, we emphasize that an immunosuppressive microenvironment can reduce the efficacy of chemo- and immunotherapy and provide examples of preclinical studies showing strategies for improving ALL treatment by targeting these immunosuppressive interactions.

Comprehensive Overview of Gene Rearrangements in Childhood T-Cell Acute Lymphoblastic Leukaemia

Acute lymphoblastic leukaemia (ALL) is a relevant form of childhood neoplasm, as it accounts for over 80% of all leukaemia cases. T-cell ALL constitutes a genetically heterogeneous cancer derived from T-lymphoid progenitors. The diagnosis of T-ALL is based on morphologic, immunophenotypic, cytogenetic, and molecular features, thus the results are used for patient stratification. Due to the expression of surface and intracellular antigens, several subtypes of T-ALL can be distinguished. Although the aetiology of T-ALL remains unclear, a wide spectrum of rearrangements and mutations affecting crucial signalling pathways has been described so far. Due to intensive chemotherapy regimens and supportive care, overall cure rates of more than 80% in paediatric T-ALL patients have been accomplished. However, improved knowledge of the mechanisms of relapse, drug resistance, and determination of risk factors are crucial for patients in the high-risk group. Even though some residual disease studies have allowed the optimization of therapy, the identification of novel diagnostic and prognostic markers is required to individualize therapy. The following review summarizes our current knowledge about genetic abnormalities in paediatric patients with T-ALL. As molecular biology techniques provide insights into the biology of cancer, our study focuses on new potential therapeutic targets and predictive factors which may improve the outcome of young patients with T-ALL.

Resource limited centres can deliver treatment for children with acute lymphoblastic leukaemia with risk-stratified minimal residual disease based UKALL 2003 protocol with no modification and a good outcome

OBJECTIVES

Acute Lymphoblastic Leukemia (ALL) is the most common malignancy in children. With improved supportive care and a better understanding of the disease biology, it is now a curable cancer in the developed world. However, in low-income countries, the cure rate remains relatively poor. We report our experience on the survival of children with ALL treated on the MRD-based risk-stratified UKALL 2003 protocol, from a center in South India.

METHODS

All consecutive children diagnosed with ALL between years 2013 and 2019 were included in this retrospective study. All received uniform treatment as per the UKALL 2003 protocol based on NCI risk and post-induction MRD status. All the details including the type of leukemia, NCI risk status, date of diagnosis, treatment start date, the regimen, MRD status, cytogenetics, molecular genetics, and complications were captured. Analysis was done using prism GraphPad version 8.0.

RESULTS

A total of 107 children were started on treatment during this period. The majority of them were boys (68/107). Fifty-nine of them were NCI standard risk (55%). B-ALL was the most common type (92%).Total of 56/107(52.3%) children received treatment under the government's insurance scheme for low-income bracket. The post-induction MRD was performed in 95/107 children. It was >0.01% in 22% (21/95) of children. Five (4.7%) children relapsed so far with a mean follow up of 27 months from the diagnosis. There were 17 deaths (15.9%). The EFS at 3 years was 85% (95% CI 75% to 92%).

CONCLUSION

It is feasible to deliver chemotherapy as per the UKALL2003 protocol without any modifications in resource-limited setting. The survival rates have significantly improved over the years in our center from 5 years EFS of 60% in 2010 and now to 3 year EFS of 85%. It is important to note that there was no treatment abandonment in our cohort.

Comparison of Early T-Cell Precursor and Non-ETP Subtypes Among 122 Chinese Adults With Acute Lymphoblastic Leukemia

Background: Adult T-cell acute lymphoblastic leukemia (T-ALL) is a rare hematological malignancy and significantly linked to poor outcomes. Early T-cell precursor (ETP) leukemia is a unique subtype of T-ALL. The aim of this study is to compare the differences between ETP and non-ETP ALLs in China.

Methods: We retrospectively analyzed the records of 122 adult T-ALL patients diagnosed and treated at our center between January 2014 and June 2019. All the patients enrolled were categorized into ETP and non-ETP ALL by immunophenotype, and further statistical analyses about clinical data and prognostic factors were performed.

Results: Among the 122 cases, the male-to-female ratio was 2.8:1, and the median age is 29 (range, 16–82) years. Except for 10 patients with insufficient immunophenotyping results, 47.3% (53/112) are ETP and 52.7% (59/112) are non-ETP. Compared with non-ETP patients, ETP-ALL patients had lower white blood cell counts and lactate dehydrogenase levels, while they were older and had higher platelet counts and fibrinogen levels (all p < 0.05). Complete remission (CR) was achieved in 68.0% (83/122) of patients, 64.2 and 76.3% in ETP and non-ETP, respectively (p = 0.160). In total, 44.6% (37/83) of patients relapsed. Allogeneic stem cell transplantation (allo-SCT) was successfully performed in 36.1% (44/122) of patients, of which 79.5% (35/44) were in CR1. With a median follow-up of 9.1 (range, 0.5–70.3) months, the estimated 2-year overall survival (OS) and relapse-free survival (RFS) rates for the cohort were 38.0 ± 5.1 and 39.1 ± 6.3%, respectively. In the ETP group, the 2-year OS rate was 40.7 ± 8.2% and the RFS rate was 47.2 ± 10.7%, while in the non-ETP group, the 2-year OS rate was 37.9 ± 7.0% and the RFS rate was 39.2 ± 8.3% (both p > 0.05). In the landmark analysis of CR1 patients who had a survival of more than 6 months, the allo-SCT group had significantly better survival outcomes than the chemotherapy group, and the 2-year OS rates and RFS rates were 80.1 ± 7.3 vs. 28.4 ± 8.4% and 68.9 ± 8.8 vs. 12.8 ± 7.2%, respectively (both p < 0.0001). A multivariate analysis suggests that allo-SCT acts as an independent prognostic factor for both OS and RFS.

Conclusions: Our results revealed that ETP accounted for a high proportion of T-ALL in Chinese. There are no CR rates and prognosis differences between ETP and non-ETP. Allo-SCT in CR1 can significantly improve patients' survival.

Radwan M, E. Ozturk S, Ulusoy NG, Sozer E, E. Ellakwa D, Ocak Z, Can M, F.S. Ali T, I. Abd-Alla H, Yayli N, Tateishi H, Otsuka M, Fujita M. Design, Synthesis and Biological Evaluation of Pentacyclic Triterpene Derivatives: Optimization of Anti-ABL Kinase Activity

Imatinib, an Abelson (ABL) tyrosine kinase inhibitor, is a lead molecular-targeted drug against chronic myelogenous leukemia (CML). To overcome its resistance and adverse effects, new inhibitors of ABL kinase are needed. Our previous study showed that the benzyl ester of gypsogenin (1c), a pentacyclic triterpene, has anti-ABL kinase and a subsequent anti-CML activity. To optimize its activities, benzyl esters of carefully selected triterpenes (PT1-PT6), from different classes comprising oleanane, ursane and lupane, and new substituted benzyl esters of gypsogenin (GP1-GP5) were synthesized. All of the synthesized compounds were purified and charachterized by different spectroscopic methods. Cytotoxicity of the parent triterpenes and the synthesized compounds against CML cell line K562 was examined; revealing three promising compounds PT5, GP2 and GP5 (IC50 5.46, 4.78 and 3.19 μM, respectively). These compounds were shown to inhibit extracellular signal-regulated kinase (ERK) downstream signaling, and induce apoptosis in K562 cells. Among them, PT5 was identified to have in vitro activity (IC50 = 1.44 μM) against ABL1 kinase, about sixfold of 1c, which was justified by molecular docking. The in vitro activities of GP2 and GP5 are less than PT5, hence they were supposed to possess other more mechanisms of cytotoxicity. In general, our design and derivatizations resulted in enhancing the activity against ABL1 kinase and CML cells.

The importance of miRNAs and epigenetics in acute lymphoblastic leukemia prognosis

Acute lymphoblastic leukemia (ALL), one of the most common malignant human disorders, originates in different important genetic lesions in T-cell or B-cell progenitors. ALL is a malignant lymphoid progenitor with peak prevalence in children (2-5 years). The rate of survival when one is suffering from ALL depends on various agents including the age of the patient, responses to anti-leukemic therapy, and cell biology. miRNAs and epigenetics are important regulatory factors in the expression of genes. miRNAs are noncoding RNA with inhibitory effectors on specific mRNA. Patterns of DNA methylation are profoundly changed in ALL by epigenetic mechanisms. The deciphering of miRNA and the epigenetic pathogenesis in ALL could revolutionize response to the therapy and outcome, and create an enormous promise for novel approaches to reduce the toxic side-effects of intensive leukemia. Hence, pathogenetic miRNAs and epigenetics leading to the initiation and the progression of ALL are summarized in this review.

Differential expression of CD73, CD86 and CD304 in normal vs. leukemic B-cell precursors and their utility as stable minimal residual disease markers in childhood B-cell precursor acute lymphoblastic leukemia

BACKGROUND

Optimal discrimination between leukemic blasts and normal B-cell precursors (BCP) is critical for treatment monitoring in BCP acute lymphoblastic leukemia (ALL); thus identification of markers differentially expressed on normal BCP and leukemic blasts is required.

METHODS

Multicenter analysis of CD73, CD86 and CD304 expression levels was performed in 282 pediatric BCP-ALL patients vs. normal bone marrow BCP, using normalized median fluorescence intensity (nMFI) values.

RESULTS

CD73 was expressed at abnormally higher levels (vs. pooled normal BCP) at diagnosis in 71/108 BCP-ALL patients (66%), whereas CD304 and CD86 in 119/202 (59%) and 58/100 (58%) patients, respectively. Expression of CD304 was detected at similar percentages in common-ALL and pre-B-ALL, while found at significantly lower frequencies in pro-B-ALL. A significant association (p = 0.009) was found between CD304 expression and the presence of the ETV6-RUNX1 fusion gene. In contrast, CD304 showed an inverse association with MLL gene rearrangements (p = 0.01). The expression levels of CD73, CD86 and CD304 at day 15 after starting therapy (MRD15) were stable or higher than at diagnosis in 35/37 (95%), 40/56 (71%) and 19/41 (46%) cases investigated, respectively. This was also associated with an increased mean nMFI at MRD15 vs. diagnosis of +24 and +3 nMFI units for CD73 and CD86, respectively. In addition, gain of expression of CD73 and CD86 at MRD15 for cases that were originally negative for these markers at diagnosis was observed in 16% and 18% of cases, respectively. Of note, CD304 remained aberrantly positive in 63% of patients, despite its levels of expression decreased at follow-up in 54% of cases.

CONCLUSIONS

Here we show that CD73, CD86 and CD304 are aberrantly (over)expressed in a substantial percentage of BCP-ALL patients and that their expression profile remains relatively stable early after starting therapy, supporting their potential contribution to improved MRD analysis by flow cytometry.

Osteonecrosis in patients with acute lymphoblastic leukaemia: a national questionnaire study

OBJECTIVES

To establish prevalence, management and long-term outcomes of osteonecrosis (ON) in young people diagnosed with acute lymphoblastic leukaemia (ALL) between 2003 and 2011.

DESIGN SETTING PARTICIPANTS

This study assessed ON in 3113 patients aged 1-24 years who participated in the UK national leukaemia study UKALL 2003. UKALL 2003 recruited patients in 40 UK hospitals between 2003 and 2011 and included patients between ages 1 and 25 diagnosed with ALL.

RESULTS

170 patients were diagnosed with ON, giving a prevalence of 5.5%. The multivariable analysis showed that the risk of ON was highest for children aged between 10 and 20 years (ages 10-15 years, OR 23.7, 95% CI 14.8 to 38.0; ages 16-20 years, OR 22.5, 95% CI 12.7 to 39.8, compared with age <10 years). Among ethnic groups, Asian patients had the highest risk of ON (OR 1.92, 95% CI 1.1 to 3.6, compared with White patients). Eighty-five per cent of patients with ON had multifocal ON. Thirty-eight per cent of patients with ON required surgery and 19% of patients with ON required a hip replacement. Fifteen per cent of patients who had surgery still describe significant disability or use of a wheelchair.

CONCLUSIONS

ON has considerable morbidity for patients being treated for ALL, with a high burden of surgery. Age and ethnicity were found to be the most significant risk factors for development of ON, with Asian patients and patients aged 10-20 years at diagnosis of ALL at greatest risk. These results will help risk stratify patients at diagnosis of ALL, and help tailor future prospective studies in this area.

T-cell acute lymphoblastic leukemia

T-cell acute lymphoblastic leukemia (T-ALL) is biologically distinct from its B lymphoblastic (B-ALL) counterpart and shows different kinetic patterns of disease response. Although very similar regimens are used to treat T-ALL and B-ALL, distinctions in response to different elements of therapy have been observed. Similar to B-ALL, the key prognostic determinant in T-ALL is minimal residual disease (MRD) response. Unlike B-ALL, other factors including age, white blood cell count at diagnosis, and genetics of the ALL blasts are not independently prognostic when MRD response is included. Recent insights into T-ALL biology, using modern genomic techniques, have identified a number of recurrent lesions that can be grouped into several targetable pathways, including Notch, Jak/Stat, PI3K/Akt/mTOR, and MAPK. With contemporary chemotherapy, outcomes for de novo T-ALL have steadily improved and now approach those observed in B-ALL, with approximately 85% 5-year event-free survival. Unfortunately, salvage has remained poor, with less than 25% event-free and overall survival rates for relapsed disease. Thus, current efforts are focused on preventing relapse by augmenting therapy for high-risk patients, sparing toxicity in favorable subsets and developing new approaches for the treatment of recurrent disease.

Augmented post-remission therapy for a minimal residual disease-defined high-risk subgroup of children and young people with clinical standard-risk and intermediate-risk acute lymphoblastic leukaemia (UKALL 2003): a randomised controlled trial

BACKGROUND

No randomised study has shown whether stratification of treatment by minimal residual disease (MRD) response improves outcome in children and young people with acute lymphoblastic leukaemia (ALL). We assessed whether children and young people with clinical standard and intermediate-risk ALL who have persistent MRD at the end of induction therapy benefit from augmented post-remission therapy.

METHODS

Between Oct 1, 2003, and June 30, 2011, we enrolled eligible patients aged 1-24 years and initially categorised them into clinical standard-risk, intermediate-risk, and high-risk groups on the basis of a combination of National Cancer Institute criteria, cytogenetics, and early morphological response to induction therapy. Clinical standard-risk and intermediate-risk patients with MRD of 0·01% or higher at day 29 of induction (MRD high risk) were randomly assigned (1:1) to standard therapy (treatment regimens A and B) or augmented post-remission therapy (regimen C). Compared with standard therapy, the augmented treatment regimen (regimen C) included an additional eight doses of pegylated asparaginase, 18 doses of vincristine, and escalated-dose intravenous methotrexate without folinic acid rescue during interim maintenance courses. Computer randomisation was used for treatment allocation and was balanced for sex, age (<10 years vs ≥10 years), and white blood cell count at diagnosis (<50 × 10(9)/L vs ≥50 × 10(9)/L) by minimisation. Patients, clinicians, and data analysts were not masked to treatment allocation. The primary outcomes were event-free survival and overall survival. Analyses were by intention to treat. This trial is registered with Current Controlled Trials, number ISRCTN07355119.

FINDINGS

533 MRD high-risk patients were randomly assigned to receive standard (n=266) or augmented (n=267) post-remission therapy. After a median follow-up of 70 months (IQR 52-91), 5-year event-free survival was better in the augmented treatment group (89·6% [95% CI 85·9-93·3]) than in the standard group (82·8% [78·1-87·5]; odds ratio [OR] 0·61 [95% CI 0·39-0·98], p=0·04). Overall survival at 5 years was numerically, but not significantly, higher in the augmented treatment group (92·9% [95% CI 89·8-96·0]) than in the standard therapy group (88·9% [85·0-92·8]; OR 0·67 [95% CI 0·38-1·17], p=0·16). More adverse events occurred in the augmented treatment group than in the standard group (asparaginase-related hypersensitivity in 18 [6·7%] in the augmented group vs two [0·8%] in the standard group and asparaginase-related pancreatitis in eight [3·0%] vs one [0·4%]; intravenous methotrexate-related mucositis in 11 [4·1%] vs three [1·1%] and methotrexate-related stomatitis in 48 [18·0%] vs 12 [4·5%]).

INTERPRETATION

Our findings suggest that children and young people with acute lymphoblastic leukaemia and 0·01% or more MRD at the end of remission induction therapy could benefit from augmented post-remission therapy. However, the asparaginase and intravenous methotrexate used in the augmented treatment regimen is associated with more adverse events than is the standard post-remission treatment regimen.

FUNDING

Medical Research Council and Leukaemia and Lymphoma Research.

Pattern of immunoglobulin and T-cell receptor-δ/γ gene rearrangements in Iranian children with B-precursor acute lymphoblastic leukemia

INTRODUCTION

Acute lymphoblastic leukemia (ALL) cells have unique rearranged immunoglobulin heavy chain (IgH), immunoglobulin light chain (IgK), and T-cell receptor (TCR) genes, which can be used as markers for clonality assay and evaluation of minimal residual disease. In this study, we have evaluated the pattern of IgH, IgK chains, and TCRG/D gene rearrangements in precursor-B ALL.

MATERIALS AND METHODS

In our prospective study, hyper-variable regions (CDRI and III) of IgH, TCRD (Vδ2-Dδ3 and Dδ2-Dδ3), TCRG (Vγ, VγI, and VγII), and IgK (Vκ-Kde) were studied in 126 cases with diagnosis of B-precursor ALL.

RESULTS

One hundred and fourteen (90.5%) out of 126 patients had clonal rearrangements of IgH using consensus primers for CDRI and/or CDRIII regions. Monoclonal, biclonal, and oligoclonal patterns were observed in 63 (57.8%), 38 (34.9%), and 6 (5.5%) patients with IgH (CDRIII) rearrangements, respectively. Clonal rearrangements of TCRG (Vγ) and VγI/II were present in 79.3 and 64.9% of patients, respectively, and only 5% of cases showed biclonal pattern. The VγII rearrangement was the most common (46.8%) type in TCRG. Vδ2-Dδ3 and Dδ2-Dδ3 partial gene rearrangements were observed in 47 (45.2%; n = 104) and 11 (16.6%; n = 66) patients, respectively. Biclonal/oligoclonal patterns were present in 13 (27.7%) and 2 (4.3%) cases with Vδ2-Dδ3 rearrangement, respectively. Only one patient had biclonal Dδ2-Dδ3 rearrangement. Clonal pattern of IgK-Kde was detected in 59 cases (67%; n = 88).

CONCLUSION

Our findings showed that clonal rearrangements of IgH and TCRD (Vδ2-Dδ3 and Dδ2-Dδ3) genes had similar patterns to other studies. Frequency of TCRG (VγI and VγII) and IgK rearrangements was found to be slightly higher than previous reports. Among the IgK rearrangements, VKI (25%) was the most common.

Diagnosis of a T-lineage acute lymphoblastic leukemia through digitalized cell analysis of the pleural effusion

Introduction

Pleural effusion as the first clinical manifestation of acute lymphoblastic leukemia (ALL) is a relatively rare event. An early and accurate diagnosis of this clinical picture is very important for adequate patient management.

Case presentation

We report the atypical onset of T-lineage ALL in a 31-year-old man. The patient was admitted to the emergency room due to lung failure; at that moment, the patient’s initial blood count was normal; the chest X-ray radiography showed a massive pleural effusion and a thoracentesis was carried out. Routine investigations performed on the pleural fluid using a new technology system and digitalized cell analysis demonstrated infiltration by immature cells. Therefore, bone marrow aspirate and flow cytometry analyses were performed, leading to the diagnosis of T-lineage ALL. A cord blood transplantation procedure was performed at the first hematological remission following chemotherapy regimens. The patient died of septic shock.

Conclusion

The case we reported underlines the usefulness of using automated instruments to identify abnormal lymphoid cells in body fluids.

Visualising the cross-level relationships between pathological and physiological processes and gene expression: analyses of haematological diseases

The understanding of pathological processes is based on the comparison between physiological and pathological conditions, and transcriptomic analysis has been extensively applied to various diseases for this purpose. However, the way in which the transcriptomic data of pathological cells relate to the transcriptomes of normal cellular counterparts has not been fully explored, and may provide new and unbiased insights into the mechanisms of these diseases. To achieve this, it is necessary to develop a method to simultaneously analyse components across different levels, namely genes, normal cells, and diseases. Here we propose a multidimensional method that visualises the cross-level relationships between these components at three different levels based on transcriptomic data of physiological and pathological processes, by adapting Canonical Correspondence Analysis, which was developed in ecology and sociology, to microarray data (CCA on Microarray data, CCAM). Using CCAM, we have analysed transcriptomes of haematological disorders and those of normal haematopoietic cell differentiation. First, by analysing leukaemia data, CCAM successfully visualised known relationships between leukaemia subtypes and cellular differentiation, and their characteristic genes, which confirmed the relevance of CCAM. Next, by analysing transcriptomes of myelodysplastic syndromes (MDS), we have shown that CCAM was effective in both generating and testing hypotheses. CCAM showed that among MDS patients, high-risk patients had transcriptomes that were more similar to those of both haematopoietic stem cells (HSC) and megakaryocyte-erythroid progenitors (MEP) than low-risk patients, and provided a prognostic model. Collectively, CCAM reveals hidden relationships between pathological and physiological processes and gene expression, providing meaningful clinical insights into haematological diseases, and these could not be revealed by other univariate and multivariate methods. Furthermore, CCAM was effective in identifying candidate genes that are correlated with cellular phenotypes of interest. We expect that CCAM will benefit a wide range of medical fields.

DNMT3A Mutations in Patients with Acute Myeloid Leukemia in South Brazil

Acute myeloid leukemia (AML) is a complex and heterogeneous hematopoietic tissue neoplasm. Several molecular markers have been described that help to classify AML patients into risk groups. DNA methyltransferase 3A (DNMT3A) gene mutations have been recently identified in about 22% of AML patients and associated with poor prognosis as an independent risk factor. Our aims were to determine the frequency of somatic mutations in the gene DNMT3A and major chromosomal translocations in a sample of patients with AML. We investigated in 82 samples of bone marrow from patients with AML for somatic mutations in DNMT3A gene by sequencing and sought major fusion transcripts by RT-PCR. We found mutations in the DNMT3A gene in 5 patients (6%); 3 were type R882H [corrected]. We found fusion transcripts in 19 patients, namely, AML1/ETO (n = 5; 6.1%), PML/RARα (n = 12; 14.6%), MLL/AF9 (0; 0%), and CBFβ/MYH11 (n = 2; 2.4%). The identification of recurrent mutations in the DNMT3A gene and their possible prognostic implications can be a valuable tool for making treatment decisions. This is the first study on the presence of somatic mutations of the DNMT3A gene in patients with AML in Brazil. The frequency of these mutations suggests a possible ethnogeographic variation.

Immunophenotypic characterization of acute leukemia at a public oncology reference center in Maranhão, northeastern Brazil

CONTEXT AND OBJECTIVES

The incidence of acute leukemia (AL) subtypes varies according to geographical distribution. The aim here was to determine the incidence of morphological and immunophenotypic AL subtypes in the state of Maranhão, Brazil, and to correlate the expression of aberrant phenotypes in children with acute lymphoblastic leukemia (ALL) with prognostic factors.

DESIGN AND SETTING

Single prospective cohort study at a public oncology reference center in Maranhão.

METHODS

Seventy AL cases were diagnosed between September 2008 and January 2010. For the diagnosis, complete blood cell counts, myelograms (at diagnosis and at the end of the induction phase), cytochemical analysis and immunophenotyping were performed.

RESULTS

Among adult patients (n = 22), the incidence of AL types was: ALL (22.7%) and acute myeloid leukemia (AML) (77.3%). The subtype AML M0 occurred most frequently (29.4%). In children (n = 48), the types were: AML (18.7%), most frequently subtype AML M4 (33.4%); biphenotypic acute leukemia (BAL) (4.2%); and ALL (77.1%), including the subtypes B-ALL (72.9%) and T-ALL (27.1%). Among the children with ALL, there were no statistically significant differences between patients with and without aberrant phenotypes, in relation to hematological parameters and treatment response.

CONCLUSION

This work demonstrates that the frequencies of AML M0 cases among adults and T-ALL cases among children in Maranhão were high. This suggests that there may be differences in AML subtype incidence, as seen with ALL subtypes, in different regions of Brazil. No association was found between the expression of aberrant phenotypes and prognostic factors, in children with ALL.

Prethymic cytoplasmic CD3 negative acute lymphoblastic leukemia or acute undifferentiated leukemia: a case report

Acute undiffentiated leukemia (AUL) is an acute leukemia with no more than one membrane marker of any given lineage. Blasts often express HLA-DR, CD34, and/or CD38 and may be positive for terminal deoxynucleotidyl transferase (TdT). The expression of CD34, HLA-DR, and CD38 has been shown in pro-T-ALL, although in this case, blasts should also express CD7 and cyCD3. However, some cases of T-ALL without CD3 in the cytoplasm and all TCR chain genes in germ line configuration are reported, features that fit well with a very early hematopoietic cell. We report a case of acute leukemia CD34+/−HLADR+CD7+CD38+cyCD3− in which a diagnosis of AUL was considered. However the blasts were also positive for CD99 and TCR delta gene rearrangement which was found on molecular studies. Therefore a differential diagnosis between AUL and an early cyCD3 negative T-ALL was debated.

MRD detection in acute lymphoblastic leukemia patients using Ig/TCR gene rearrangements as targets for real-time quantitative PCR

Minimal residual disease (MRD) diagnostics has proven to be clinically relevant for evaluation of treatment effectiveness in patients with acute lymphoblastic leukemia (ALL). In most ALL treatment protocols, MRD diagnostics is performed by real-time quantitative PCR (RQ-PCR) analysis of the junctional regions of rearranged immunoglobulin (Ig) and T-cell receptor (TCR) genes.MRD diagnostics via Ig/TCR genes is broadly applicable (>95% of ALL patients) and can reach a good sensitivity (< or =10 (-4)). However, the technique is complex and requires extensive knowledge and experience, because the junctional regions of each leukemia have to be identified before the patient-specific RQ-PCR assays can be designed for MRD monitoring. This chapter provides all relevant background information and technical aspects for the complete laboratory process from detection of the clonal Ig/TCR gene rearrangements in ALL cells at diagnosis to the actual MRD measurements in clinical follow-up samples. This information aims at facilitating the PCR-based MRD diagnostics in ALL patients. However, it should be noted that MRD diagnostics for clinical treatment protocols has to be accompanied by regular international quality control rounds to ensure the reproducibility and reliability of the MRD results.

Immunophenotyping of lymphoproliferative disorders: state of the art

Immunophenotyping was introduced into diagnostic pathology over 30 years ago to assist in the diagnosis and classification of lymphoproliferative disorders. Today the role of immunophenotyping has been expanded beyond this to include the detection of markers of prognosis, determination of disease phenotypes associated with specific chromosomal abnormalities, detection of targets for immunotherapy and to monitor residual disease. Immunoperoxidase detection methods remain the most popular in histopathology, whilst flow cytometry is most commonly applied for haematological samples. The range of monoclonal antibodies available, including those which work in routinely performed tissue specimens, continues to increase. This is in part a result of gene expression studies identifying precise genetic signatures for certain lymphoproliferative disorders and the generation of new protein markers to gene products of upregulated genes. This review summarises the current status and applications of immunophenotyping in the assessment of many of the lymphoid malignancies.

Carrier frequency of mutation 657del5 in the NBS1 gene in a population of polish pediatric patients with sporadic lymphoid malignancies

Nijmegen breakage syndrome (NBS) is a human autosomal recessive disease characterized by genomic instability and enhanced cancer predisposition, in particular to lymphoma and leukemia. Recently, significantly higher frequencies of heterozygous carriers of the Slavic founder NBS1 mutation, 657del5, were found in Russian children with sporadic lymphoid malignancies, and in Polish adults with non-Hodgkin lymphoma (NHL). In addition, the substitution 643C>T (R215W) has also been found in excess among children with acute lymphoblastic leukemia (ALL). In an attempt to asses the contribution of both mutations to the development of sporadic lymphoid malignancies, we analyzed DNA samples from a large group of Polish pediatric patients. The NBS1 mutation 657del5 on one allele was found in 3 of 270 patients with ALL and 2 of 212 children and adolescents with NHL; no carrier was found among 63 patients with Hodgkin lymphoma (HL). No carriers of the variant R215W were detected in any studied group. The relative frequency of the 657del5 mutation was calculated from a total of 6,984 controls matched by place of patient residence, of whom 42 were found to be carriers (frequency = 0.006). In the analyzed population with malignancies, an increased odds ratio for the occurrence of mutation 657del5 was found in comparison with the control Polish population (OR range 1.48-1.85, 95% confidence interval 1.18-2.65). This finding indicates that the frequency of the mutation carriers was indeed increased in patients with ALL and NHL (p < 0.05). Nonetheless, NBS1 gene heterozygosity is not a major risk factor for lymphoid malignancies in childhood and adolescence.