Childhood Acute Lymphoblastic Leukemia Patients Research Articles

Outcome of the Modified St. Jude Total XV Protocol in Turkish Children with Newly Diagnosed Acute Lymphoblastic Leukemia: A Single-Center Retrospective Analysis

The prognostic factors and outcomes of Turkish children with newly diagnosed acute lymphoblastic leukemia (ALL), treated with the Modified St. Jude Total XV Protocol, which was adjusted by adding high-dose methylprednisolone (HDMP) before induction in the original protocol, were assessed in this study. The Modified St. Jude Total XV Protocol was administered to 183 newly diagnosed ALL patients, aged 1-18 years, between 1 January 2008 and 30 January 2016. HDMP was applied at doses of either 10 mg/kg/day (Group A) or 20 mg/kg/day (Group B) for 7 days before induction and then tapered over the next 7 days to 5 or 10 mg/kg/day, and continued at 2 mg/kg/day for 2 weeks during the induction phase. Absolute blast count (ABC) in peripheral blood and minimal residual disease (MRD) in bone marrow were assessed at the end of the initial 7-day HDMP treatment. MRD in the bone marrow was evaluated on day 15 and at the end of the induction period. The follow-up for these patients ended on 15 July 2019. The 5-year event-free (EFS) and overall survival (OS) rates for all patients were 85.6±2.6% and 89.2±2.3%, respectively. The rate of good response to steroids (defined as ABC in peripheral blood of less than 1000/mm3 on day 7) was 88% and 97% of children achieved complete remission after induction. The survival rate and infection frequency did not show statistically significant differences between Group A and B. EFS and OS correlated with initial leukocyte count, age of 10-18 years at diagnosis, CD20 positivity at diagnosis, and gram-negative bacterial infection during remission induction. The remarkable response rates on days 7 and 15, along with the promising EFS and OS results in childhood ALL patients treated with the Modified St. Jude Total XV Protocol, highlight the early and substantial response effect of HDMP. At the onset of induction, short-term HDMP can be initiated, preferably at 10 mg/kg/day for the first 7 days, to minimize potential side effects.

Early-life tobacco exposure is causally implicated in aberrant RAG-mediated recombination in childhood acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is the most common cancer in children, yet few environmental risk factors have been identified. We previously found an association between early-life tobacco smoke exposure and frequency of somatic deletions of 8 leukemia driver genes among childhood ALL patients in the California Childhood Leukemia Study. To expand analysis genome-wide and examine potential mechanisms, we conducted tumor whole-genome sequencing in 35 ALL patients, including 18 with high prenatal tobacco exposure and 17 with low exposure as determined by established epigenetic biomarkers. High tobacco exposure patients had significantly more structural variants (P < .001) and deletions (P = .001) genome-wide than low exposure patients. Investigation of off-target RAG recombination revealed that 41% of deletions in the high tobacco exposure patients were putatively RAG-mediated (full RAG motif identified at one or both breakpoints) compared with only 21% in the low exposure group (P = .001). In a multilevel model, deletions in high tobacco exposure patients were 2.44-fold (95% CI:1.13-5.38) more likely to be putatively RAG-mediated than deletions in low exposure patients. No point mutational signatures were associated with prenatal tobacco exposure. Our findings suggest that early-life tobacco smoke exposure may promote leukemogenesis by driving development of somatic deletions in pre-leukemic lymphocytes via off-target RAG recombination.

Differential metabolomic pathway analysis in Malaysian childhood acute lymphoblastic leukemia patients treated with high-dose methotrexate

BackgroundMethotrexate (MTX) is the mainstay of the consolidation and maintenance phase of chemotherapy protocol for childhood acute lymphoblastic leukemia (ALL). This study aimed to investigate the altered metabolism associated with high dose-MTX and determine the potential of the metabolic markers and differential pathways involved in MTX therapy. MethodsSerum samples were collected from 38 children with ALL at 2 time points: p-MTX; before induction chemotherapy was initiated, and post-MTX; after completion of the first high-dose MTX. The samples were analyzed using HPLC/MS-QTOF. Data acquisition was performed using Agilent MassHunterTMB.05.00 software for subsequent metabolomics analysis. Differential expressions of metabolites were analyzed using univariate Welch's t-test unequal variance. Compounds were identified using the METLIN Database. Pathways and network analyses were performed using Metaboanalyst 4.0. Potential biomarkers were analyzed using the Receiving Operator Characteristic curve. ResultsMetabolites with AUC between 0.7 and 0.9 include xanthine (0.889), oxoglutaric acid (0.770), and alpha-linolenic acid (ALA) (0.741). Alpha-linolenic acid abundance was detected in ALL patients with remission status, corresponding to a test sensitivity and specificity of 0.77 and 0.87, respectively. ALA has an antineoplastic effect that potentially inhibits the proliferation of leukemic cells by inhibiting caspase activation in the phosphatidylinositol 3-kinase (PI3K) pathway and Bcl-2 inhibition. ConclusionIn this study, ALA was found to be significantly higher in patients treated with high-dose MTX and associated with remission status than in pre-MTX treatment.

Incidence of bacterial and fungal infections in Polish pediatric patients with acute lymphoblastic leukemia during the pandemic

The most common complications related to the treatment of childhood acute lymphoblastic leukemia (ALL) are infections. The aim of the study was to analyze the incidence and mortality rates among pediatric patients with ALL who were treated in 17 Polish pediatric hematology centers in 2020–2021 during the pandemic. Additionally, we compared these results with those of our previous study, which we conducted in the years 2012–2017. The retrospective analysis included 460 patients aged 1–18 years with newly diagnosed ALL. In our study, 361/460 (78.5%) children were reported to have microbiologically documented bacterial infections during chemotherapy. Ten patients (2.8%) died due to sepsis. Fungal infections were reported in 99 children (21.5%), of whom five (5.1%) died due to the infection. We especially observed an increase in bacterial infections during the pandemic period compared to the previous study. The directions of our actions should be to consider antibiotic prophylaxis, shorten the duration of hospitalization, and educate parents and medical staff about complications (mainly infections) during anticancer therapy. It is necessary to continue clinical studies evaluating infection prophylaxis to improve outcomes in childhood ALL patients.

Characterisation of FLT3 alterations in childhood acute lymphoblastic leukaemia

BackgroundAlterations of FLT3 are among the most common driver events in acute leukaemia with important clinical implications, since it allows patient classification into prognostic groups and the possibility of personalising therapy thanks to the availability of FLT3 inhibitors. Most of the knowledge on FLT3 implications comes from the study of acute myeloid leukaemia and so far, few studies have been performed in other leukaemias.MethodsA comprehensive genomic (DNA-seq in 267 patients) and transcriptomic (RNA-seq in 160 patients) analysis of FLT3 in 342 childhood acute lymphoblastic leukaemia (ALL) patients was performed. Mutations were functionally characterised by in vitro experiments.ResultsPoint mutations (PM) and internal tandem duplications (ITD) were detected in 4.3% and 2.7% of the patients, respectively. A new activating mutation of the TKD, G846D, conferred oncogenic properties and sorafenib resistance. Moreover, a novel alteration involving the circularisation of read-through transcripts (rt-circRNAs) was observed in 10% of the cases. Patients presenting FLT3 alterations exhibited higher levels of the receptor. In addition, patients with ZNF384- and MLL/KMT2A-rearranged ALL, as well as hyperdiploid subtype, overexpressed FLT3.DiscussionOur results suggest that specific ALL subgroups may also benefit from a deeper understanding of the biology of FLT3 alterations and their clinical implications.

Prognostic Features of CD9 in Childhood Acute Lymphoblastic Leukemia - a Retrospective Analysis of a Nation-Wide Multicenter Study in China

Background and objectives: The outcomes of children with acute lymphoblastic leukemia (ALL) have been incrementally improved with risk-directed chemotherapy but therapy responses remain heterogeneous in clinically defined risk groups. Parameters with added prognostic values are therefore warranted to refine the current risk stratification system and inform appropriate management. CD9, a cell surface protein presented on malignant lymphoblasts, may have such predictive characteristics as shown by our previous single-center study conducted in Hong Kong (Leung et al, Leukemia, 2020). This study aims to determine the precise prognostic features of CD9 in a nation-wide, multicenter childhood ALL cohort in China, and deliver algorithms for identification of patients who may benefit from early interventions. Study design and outcome measures: This multicenter cohort study included childhood ALL patients (aged &amp;lt;18 years) enrolled into the Chinese Children Cancer Group (CCCG)-ALL-2015 study from January 2015 to December 2019, with 7,640 patients from 20 tertiary hospitals in China treated with a uniform protocol. A total of 3,781 subjects (49.5%) from 16 sites had flow cytometry data on lymphoblast CD9 at diagnosis. The final study cohort comprised 3,395 B-ALL and 386 T-ALL patients with a median follow-up of 53.9 months. The primary outcomes were 5-year overall survival (OS), event-free survival (EFS), and cumulative incidence of relapse (CIR) for patients with CD9 + or CD9 - phenotypes (positivity defined by the presence of ≥20% CD9 + blasts evaluated through a univariate analysis demonstrating the highest odds for adverse events or relapse at this cut-off). The secondary outcomes were 5-year OS, EFS, and CIR rates of CD9 + and CD9 - patients after inclusion of known prognostic factors, including risk assignment, cytogenetic anomalies, and minimal residual disease (MRD) status. Survival benefits of CD9 + subjects from treatment intensification or hematopoietic stem cell transplantation (HSCT) were analyzed. Results: CD9 was expressed in 88.5% of B-ALL and 27.9% of T-ALL cases. It conferred a dismal EFS (82.1% vs. 89.3%, P=0.001) and a higher CIR (15.5% vs. 7.8%, P&amp;lt;0.001) in B-ALL but not T-ALL patients. The prognostic impact of CD9 is much more prominent in subjects with adverse presenting features or poor early treatment responses, as best exemplified in those assigned to the intermediate/high-risk arms (EFS: 72.8% vs. 83.2%, P=0.028; CIR: 23.1% vs. 10.2%, P=0.003) or those with positive MRD at day 19 (EFS: 65.2% vs. 82.0%, P=0.053; CIR: 30.3% vs. 9.7%, P=0.007). The adverse impact of CD9 is confined to specific cytogenetics, including BCR-ABL1 (CIR: 39.5% vs. 0%, P=0.019) and normal karyotype (CIR: 15.0% vs. 6.8%, P=0.034). In multivariate analyses, CD9 remains an independent factor predicting event-free survival (HR=1.917, P=0.001) and relapse (HR=2.208, P&amp;lt;0.001). The time to and site of relapse did not differ between CD9 + and CD9 - patients. For CD9 + patients with MRD at the end of induction, treatment upstaging only benefited initial low-risk subjects. HSCT at first remission did not improve the outcomes of high-risk subjects with a CD9 + phenotype. Conclusions: This is the largest study to evaluate the significance of CD9 in childhood ALL. We confirmed the results of our previous single-center study with this multicenter national study. CD9 positivity is definitively associated with a higher relapse probability particularly for patients with intermediate/high risk diseases, MRD positivity or specific cytogenetic background. BCR-ABL1 + patients with a CD9 - phenotype had excellent outcomes and HSCT may not be required. Whereas MRD + patients who were CD9 + had poor outcomes, and therefore should have early interventions with innovative treatments to reduce the risk of relapse. With these, we propose to incorporate CD9 into the diagnostic immunophenotyping panel to inform risk stratification and management of childhood ALL.

Clinical and laboratory effects of exchange transfusion in pediatric acute lymphoblastic leukemia with hyperleukocytosis

Background Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. Emergency complications such as hyperleukocytosis can arise as the disease develops. Exchange transfusion is one of many cytoreductive modalities to resolve the condition.&#x0D; Objective To analyze the clinical and laboratory effects of exchange transfusion in childhood acute lymphoblastic leukemia patients with hyperleukocytosis.&#x0D; Methods This analytical retrospective cohort study with a pre- and post-test design used secondary medical record data. The obtained characteristics were the incidences of dyspnea, tachypnea, headache, intracranial bleeding, hepatomegaly, splenomegaly, lymphadenopathy, abdominal pain, fever, pallor, nausea/vomiting, and skin or mucosal bleeding; hemoglobin, white blood cell, and platelet counts; and serum potassium, sodium, calcium, phosphate, blood urea nitrogen, and creatinine levels.&#x0D; Results A total of 16 patients underwent exchange transfusion; they had significant reductions of the incidence of dyspnea, tachypnea, hepatomegaly, and pallor and significant improvement in the form of elevation of hemoglobin level and decrease in white blood cell counts (P&lt;0.05 for all) compared to pre-treatment. The remainder of the variables were not significantly different between pre- and post-treatment, but a general decrease in all clinical manifestations except intracranial bleeding was observed.&#x0D; Conclusion Exchange transfusion has the beneficial effect of resolving hyperleukocytosis and its manifestations, although correction in laboratory outcomes that remained abnormal are still needed.

Metabolomic profiling reveals the mechanisms underlying the nephrotoxicity of methotrexate in children with acute lymphoblastic leukemia.

Methotrexate is widely recommended as a first-line treatment for the intensive systemic and consolidation phases of childhood acute lymphoblastic leukemia. However, methotrexate-induced nephrotoxicity is a severe adverse reaction, of which the mechanisms remain unclear. An untargeted metabolomics analysis of serum from childhood acute lymphoblastic leukemia patients with delayed methotrexate excretion, with or without acute kidney injury, was performed to identify altered metabolites and metabolic pathways. An independent external validation cohort and in vitro HK-2 cell assays further verified the candidate metabolites, and explored the mechanisms underlying the nephrotoxicity of methotrexate. Four metabolites showed significant differences between normal excretion and delayed excretion, seven metabolites reflected the differences between groups with or without acute kidney injury, and six pathways were finally enriched. In particular, oxidized glutathione was confirmed as a candidate metabolite involved in the toxicity of methotrexate. We further explored the role of glutathione deprivation-induced ferroptosis on methotrexate cytotoxicity, and it was found that methotrexate overload significantly reduced cell viability, triggered reactive oxygen species and intracellular Fe2+ accumulation, and altered the expression of ferroptosis-related proteins in HK-2 cells. These methotrexate-induced changes were alleviated or reversed by the administration of a ferroptosis inhibitor, further suggesting that ferroptosis promoted methotrexate-induced cytotoxicity in HK-2 cells. Our findings revealed complex metabolomic profiles and provided novel insights into the mechanism by which ferroptosis contributes to the nephrotoxic effects of methotrexate.

Measurable residual disease study through three different methods can anticipate relapse and guide early interventions in childhood acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is the most common cancer among children. Measurable residual disease (MRD, previously named minimal residual disease) study can guide therapy adjustments or preemptive interventions that might avoid hematological relapse. Clinical decision making and patient outcome were evaluated in 80 real-life childhood ALL patients, according to the results observed in 544 bone marrow samples analyzed with three MRD methods: multiparametric flow cytometry (MFC), fluorescent in-situ hybridization (FISH) on B or T-purified lymphocytes and patient-specific nested reverse transcription polymerase chain reaction (RT-PCR). Estimated 5year overall survival and event-free survival were 94% and 84.1%, respectively. A total of 12 relapses in 7 patients were associated with positive MRD detection with at least one of the three methods: MFC (p < 0.00001), FISH (p < 0.00001) and RT-PCR (p = 0.013). MRD assessment allowed the anticipation of relapse and adapted early interventions with different approaches including chemotherapy intensification, blinatumomab, HSCT and targeted therapy to halt relapse in five patients, although two of them relapsed afterwards. MFC, FISH and RT-PCR are complementary methods for MRD monitoring in pediatric ALL. Although, our data clearly show that MDR positive detection is associated with relapse, continuation of standard treatment, intensification or other early interventions were able to halt relapse in patients with different risks and genetic background. More sensitive and specific methods are warranted to enhance this approach. However, whether early treatment of MRD can improve overall survival in patients with childhood ALL needs to be evaluated in adequately controlled clinical trials.

Hyperleukocytosis in Childhood Acute Leukemia: Early Complications and Survival Outcomes

Hyperleukocytosis and extreme hyperleukocytosis, defined as initial white blood cell counts greater than 100 × 109/L and 200 × 109/L, respectively, have been associated with unfavorable outcomes. This study aimed to determine the early complications and survival outcomes of childhood leukemia patients with hyperleukocytosis. The medical records of 690 children newly diagnosed with acute leukemia between January 1998 and December 2017 were retrospectively reviewed. The Kaplan–Meier method and log-rank test were used to assess and compare the survival outcomes. Multivariate Cox proportional hazards regression was used to determine associated risk factors for overall survival. We found that 16.6% of 483 childhood acute lymphoblastic leukemia (ALL) patients and 20.3% of 207 childhood acute myeloid leukemia (AML) patients had hyperleukocytosis at diagnosis. ALL patients with hyperleukocytosis had more early complications than those without hyperleukocytosis (p &lt; 0.05). Among the ALL group, the 5-year overall survival rate for those with hyperleukocytosis was significantly lower than for those without hyperleukocytosis (37.2% vs. 67.8%, p &lt; 0.0001), while the difference was not statistically significant in the AML group (19.0% vs. 30.2%, respectively, p = 0.26). Hyperleukocytosis (hazard ratio [HR]: 2.04), extreme hyperleukocytosis (HR: 2.71), age less than 1 year (HR: 3.05), age greater than 10 years (HR: 1.64), and male sex (HR: 1.37) were independently associated with poorer overall survival in childhood ALL patients. Extreme hyperleukocytosis (HR: 2.63) and age less than 1 year (HR: 1.82) were independently associated with poorer overall survival in AML patients. Hyperleukocytosis was associated with adverse survival outcomes in childhood leukemia.

L-asparaginase activity and anti-L-asparaginase antibody as biomarkers in estimating PEG-asp-related anaphylaxis risk in childhood acute lymphoblastic leukemia patients.

L-Asparaginase (L-asp), the unconjugated form of polyethylene glycol-conjugated L-asparaginase (PEG-asp), regulates T cell stimulation, antibody production, and lysosomal protease activity to mediate PEG-asp-related anaphylaxis. This study aimed to investigate the relation of L-asp activity and anti-L-asp antibody with anaphylaxis risk and non-anaphylaxis adverse reaction risk in childhood acute lymphoblastic leukemia (ALL) patients who underwent PEG-asp contained therapy. In total, 170 childhood ALL patients underwent PEG-asp-contained treatment and their L-asp activity and anti-L-asp antibody were detected on the 7th day after treatment initiation. There were 27 (15.9%) patients who had PEG-asp-related adverse reaction: 17 (10.0%) patients experienced PEG-asp-related anaphylaxis and 14 (8.2%) patients experienced PEG- asp-related non-anaphylaxis adverse reaction. Moreover, L-asp activity was negatively related to anti-L-asp antibody in childhood ALL patients (P<0.001). Elevated L-asp activity was associated with the absence of PEG-asp-related anaphylaxis (P<0.001), PEG-asp-related non-anaphylaxis adverse reaction (P=0.004), and PEG-asp-related adverse reaction (P<0.001). However, the anti- L-asp antibody displayed opposite trend similar to L-asp activity. Receiver operating characteristic (ROC) curve analyses exhibited L-asp activity and anti-L-asp antibody exhibited superior predictive values in estimating PEG-asp-related anaphylaxis risk with area under curve (AUC) of 0.955 and 0.905, respectively compared to PEG-asp-related non-anaphylaxis adverse reaction risk with AUC of 0.730 and 0.675, respectively. Besides, patients with de novo disease, higher risk stratification, and allergic history showed trends linked with PEG-asp-related anaphylaxis risk. The monitoring of L-asp activity and anti-L-asp antibody maybe useful for early estimation and prevention of PEG-asp-related anaphylaxis in childhood ALL management.

Impact of TP53 gene variants on prognosis and survival of childhood acute lymphoblastic leukemia

The tumor suppressor protein 53 (TP53) gene is one of the most studied genes in cancer. Although TP53 variants are rare events in acute leukemia, recent observations showed that relapse samples might harbor TP53 variants. Here, we aimed to determine TP53 variants (hotspot region, exon 4–11) in childhood acute lymphoblastic leukemia (B and T-ALL) patients (n = 94) including diagnostic-relapse pairs (n = 15) by amplicon sequencing and evaluate the clinical impact of these variants. In total, nine different (E298*, R283C, R273H, L252F, C229F, I195T, E286G, c.955_956insC, and c.920-1G > C) variants were identified in 17 (18%) childhood ALL patients. c.(920-1G> C) splice site variant and c.(955_956insC) insertion were reported for the first time. In diagnose-relapse pair samples, we identified acquired and/or loss of TP53 variants in the samples at the time of relapse. TP53 variants were found to be more common in T-ALL (37%) than in B-ALL patients (9%). Pathogenic TP53 variants were associated with a shorter overall survival time (p = 0.001).TP53 variants were found to be associated with inferior outcomes in our cohort and can be an independent risk factor for poor prognosis in childhood acute leukemia patients. Identification of low-frequent variants with next-generation sequencing approaches enables better knowledge of the clonal dynamics of ALL.

Çocukluk Çağı Akut Lenfoblastik Lösemi Hastalarında Tedavi Sırasında Gelişen Akut Endokrin ve Metabolik Komplikasyonların Retrospektif Değerlendirilmesi

Çocukluk Çağı Akut Lenfoblastik Lösemi Hastalarında Tedavi Sırasında Gelişen Akut Endokrin ve Metabolik Komplikasyonların Retrospektif Değerlendirilmesi

IL16 and factor V gene variations are associated with asparaginase-related thrombosis in childhood acute lymphoblastic leukemia patients.

Aim: We previously conducted exome-wide association study in acute lymphoblastic leukemia patients and identified association of five SNPs with asparaginase-related thrombosis. Here we aimed to replicate these findings in an independent patient cohort and through analyses in vitro. Patients & methods: SNPs located in IL16, MYBBP1A, PKD2L1, RIN3 and MPEG1 genes were analyzed in patients receiving Dana-Farber Cancer Instituteacute lymphoblastic leukemia treatment protocols 05-001 and 11-001. Thrombophilia-related variations were also analysed. Results: IL16 rs11556218 conferred higher risk of thrombosis and higher in vitro sensitivity to asparaginase. The association was modulated by the treatment protocol, risk group and immunophenotype. A crosstalk between factor V Leiden, non-O blood groups and higher risk of thrombosis was also seen. Conclusion: IL16 and factor V Leiden variations are implicated in asparaginase-related thrombosis.

Fishing for ETV6/RUNX1 fusion and MLL gene rearrangements and their additional abnormalities in childhood acute lymphoblastic leukemia patients of Kashmir

ObjectiveEvidence suggests that ETV6/RUNX1 translocation in pediatric acute lymphocytic leukemia shows geographical variation. Therefore, the present study aimed at unveiling the incidence of ETV6/RUNX1 fusion in pediatric acute lymphocytic leukemia cases of this region using fluorescent in-situ hybridization. Besides, we aimed to determine the incidence of MLL gene rearrangement and the pattern of chromosomal abnormalities in this study group. MethodsSamples from 57 acute lymphocytic leukemia cases of pediatric age group were subjected to fluorescent in-situ hybridization and conventional cytogenetic analysis using standard methods. ResultsConventional cytogenetic analysis revealed chromosomal abnormalities in 19.3% cases. The other major chromosomal abnormalities reported were monosomies in 10.5%, hypodiploidy in 7%, marker chromosomes in 3.5% and deletions in 3.5% cases. We found a 44,XX,-7,-18, r(5), i(17q) complex karyotype in one of the cases. Fluorescent in-situ hybridization analysis revealed ETV6/RUNX1 translocation to be present in 28.07% cases and MLL gene rearrangement in 3.5% cases. 12.5% of ETV6/RUNX1 fusion positive cases were found to have a loss of ETV6 allele. Besides, 8.8% cases were found to exhibit a signal pattern suggestive of RUNX1 amplification. ETV6 gene deletion and MLL gene amplification was detected in 3.5% cases each, of our study. ConclusionsFrequency of ETV6/RUNX1 fusion oncogene was found to be higher in pediatric ALL cases of Kashmir region as compared to that reported from other parts of India. Besides, a case was found to have a karyotype viz 44,XX,-7,-18, r(5), i(17q) that has not been reported elsewhere in the childhood ALL.

PROM1 and CTGF Expression in Childhood MLL-Rearrangement Acute Lymphoblastic Leukemia.

The prognosis of over 90% of infant acute lymphoblastic leukemia (ALL) remains poor because of harboring the mixed-lineage leukemia gene (MLL) fusion. To give insight into the critical coexpressed genes related to the MLL-rearrangement (MLL-R) gene in childhood acute lymphoblastic leukemia, we integrated different bioinformatic methods. First, the gene expression data of MLL-R ALL and normal samples from GSE13159 and GSE13164 were analyzed using “compare” function in the Oncomine database. The top 150 overexpressed and 150 underexpressed genes were identified by the Oncomine website. Then, we employed the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) to define functional genes for the 300 DEGs. The Cytoscape identified two important networks for overexpressed genes, including 35 functional genes, among which PROM1, FLT3, CTGF, LGALS1, IGFBP7, ZNRF1, and RUNX2 were considered as the key genes because of their high expression in MLL-R ALL compared to the expression in other subclassification of leukemia in the MILE dataset. Further analysis of GSE68720, GSE19475, and Therapeutically Applicable Research to Generate Effective Treatments (TARGET) ALL (phase I) database confirmed the robust expression of 7 key genes in MLL-R compared to MLL-germline (MLL-G) childhood ALL. Kaplan-Meier analysis indicated that childhood ALL patients with high PROM1 and CTGF expression had significantly poor overall survival. These findings suggest that PROM1 and CTGF represent two potential therapeutic targets for childhood MLL-R ALL.

The Significance of soluble CD40 and CD40 ligand levels in childhood acute lymphoblastic leukemia patients

Background and aim: Acute lymphoblastic leukemia (ALL) is the most prevalent malignant disorder in childhood. CD40 is a member of the tumor necrosis factor (TNF) receptor family. Soluble CD40 (sCD40) was previously found to be associated with poor prognosis in adult patients with hematologic malignancies such as acute myeloid leukemia (AML) and multiple myeloma. Experience in children, however, is rather limited. The present study aimed to investigate the significance of sCD40 and sCD40 ligand in children with ALL.&#x0D; Materials and Method: This study recruited 44 children treated at Erciyes University, Division of Pediatric Hematology &amp; Oncology between February 2008 and February 2010. We investigated the relationship between sCD40/sCD40 ligand at the diagnosis and remission during continuation phase with the prognosis of children with ALL. We also considered the data on treatment response, relapse, and outcome.&#x0D; Findings: The participating patients (20 girls and 25 boys) were between 22 months - 18 years (mean 7.6 ± 4.6 years) and had leukocytes at diagnosis between 870 - 741,660/mm3 (median 15,150/mm3). Thirty-five patients were diagnosed with B, whereas nine were diagnosed with T phenotype. In this cohort, 13 patients were classified in the standard-risk (SR) group, 20 patients were put in the intermediate-risk (IR) group, and 11 patients were categorized in the (HR) group according to the Turkish Acute Lymphoblastic Leukemia Berlin Frankfurt Munich (TR-ALL BFM) protocol. The serum levels of CD40/CD40 ligand at diagnosis were 22.41±9.91 ng/ml and 15.17±5.49 ng/ml, respectively, whereas these levels at remission were 0.22±0.38 ng/ml and 1.04±0.51 ng/ml, respectively. We detected significant changes in CD40 and CD40 ligand levels (p = 0.008 and p&lt;0.005, respectively) and early response on the 8th day. Although not significantly correlated with sCD40, the final outcome had a significant relationship with early response detected on the 8th day of treatment. We found the cut-off value of sCD40 to be 28.15 ng/dL in our cohort. The effect of sCD40 on event-free survival was clinically significant, but it did not yield statistical significance.&#x0D; Conclusion: Overall, our findings suggest that sCD40 is measured as increased at diagnosis of childhood ALL. On the basis of its physiological effect, sCD40 may have a role in modulating antitumor response in pediatric ALL and be a useful prognostic marker.

Mixed-Lineage Leukemia

Introduction: Acute Leukemia with Mixed Lineage phenotype (MLL) is leukemia that consists of cells characterized by mixed lineage markers, both from myeloid and lymphoid cells. The incidence of this leukemia is only 2-5% of all acute leukemias and is considered to have a poor prognosis.Case Presentation: A seven-year-old girl was diagnosed with MLL. The results of immunophenotyping showed two blast populations with the expressions of CD33, CD34, HLA-DR, CD117, CD13, CD19, CD10, CD20, CyMPO, Cy CD79a, and morphological features of Acute Lymphoblastic Leukemia (ALL) and Acute nonLymphocytic Leukemia (AnLL) on bone marrow aspiration. The BCR-ABL examination showed the detected BCR-ABL p210 (Major breakpoint), the majority of which was found in chronic myeloid leukemia (CML) patients. There is no definite pathogenesis of BCR-ABL p210 (MBCR-ABL) in this patient. BCR-ABL can also present in 11–29% of ALL patients but is relatively rare in childhood ALL (1%–3%) and mostly expresses p190 (minor breakpoint (mBCR-ABL)). The p210 BCR-ABL transcript is detected in 30% of adults and 20% of childhood ALL patients with Philadelphia ALL. Conclusions: MLL with BCR-ABL p210 transcript is very rare in acute leukemia. Immunophenotyping tests can detect typical MLL profiles, and WHO has standardized the diagnosis for MLL.

Inflammation-related Gene Polymorphisms Associated With Childhood Acute Lymphoblastic Leukemia.

Acute lymphoblastic leukemia (ALL) is a malignant hematological disease and is often accompanied by a variety of genetic abnormalities. The pathogenesis of inflammation-related single-nucleotide polymorphism (SNP) in children with ALL remains unclear. This study was to discover the association of the SNP sites of some inflammation-related genes and the susceptibility and treatment response of ALL in children, so as to provide personalized treatment for ALL in children. One hundred sixty-five childhood ALL patients and 175 age-matched healthy participants were recruited in this study. We investigated the involvement of 31 SNPs of the inflammation-related genes in the pathogenesis and treatment response of childhood ALL. Statistical analysis revealed that rs2280714 in IRF5, rs2297630 in SDF-1, rs4353135 in NLRP3, rs1946518 in interleukin-18 were related to the susceptibility to pediatric ALL. Interleukin-1β rs16944 SNP was correlated with ALL risk stage in children. Rs7633631 in CD226 and rs10818488 in TRAF1 were related to the minimal residual disease (MRD) on day 15 and day 33. Certain SNPs of inflammation genes were associated with the susceptibility and treatment response of ALL children. These findings may help in the early detection, diagnostic evaluation, and making individual chemotherapy regimen for ALL children according to the genotype of these sites at the time of initial diagnosis.

Polo-like Kinase 4: the Variation During Therapy and its Relation to Treatment Response and Prognostic Risk Stratification in Childhood Acute Lymphoblastic Leukemia Patients.

Polo-like kinase 4 (PLK4) plays an essential role in the tumorigenesis of some blood malignancies; consequently, we hypothesized that PLK4 might serve as a potential biomarker in childhood acute lymphoblastic leukemia (ALL) patients. Therefore, this study investigated the expression of PLK4 and its clinical relevance in childhood ALL patients. Bone marrow specimens were collected from 95 childhood ALL patients and 20 primary immune thrombocytopenia patients (as controls), and their PLK4 expression (reverse transcription-quantitative polymerase chain reaction) was measured after enrollment. Besides, the PLK4 expression in childhood ALL patients was also determined at day 15 after the initiation of induction therapy (D15). PLK4 was increased in childhood ALL patients compared with controls (2.830 (interquartile range (IQR): 1.890-3.660) versus 0.976 (IQR: 0.670-1.288), P ≤0.001). PLK4 at diagnosis was elevated in T cell acute lymphoblastic leukemia patients than in B cell acute lymphoblastic leukemia patients ( P =0.027). Besides, PLK4 at diagnosis was positively linked with the Chinese Medical Association risk stratification ( P =0.016), but not with prednisone response ( P =0.077) or bone marrow response ( P =0.083). In addition, PLK4 was decreased at D15 after treatment compared with at diagnosis ( P ≤0.001). Interestingly, PLK4 at D15 (P=0.033) was elevated in T cell acute lymphoblastic leukemia patients than in B cell acute lymphoblastic leukemia patients. Furthermore, increased PLK4 at D15 was associated with poor prednisone response ( P =0.018), poor bone marrow response ( P =0.034), and increased the Chinese Medical Association risk stratification ( P =0.015). In terms of prognosis, high PLK4 was associated with shorter event-free survival ( P =0.020), whereas it was not related to the overall survival ( P =0.135). In conclusion, PLK4 has the potential as a biomarker for treatment response and prognostic risk stratification of childhood ALL patients.