Prognosis In Pediatric Acute Lymphoblastic Leukemia Research Articles

The RAS-signaling-pathway-mutation-related prognosis in B-cell acute lymphoblastic leukemia: A report from South China children's leukemia group.

The next-generation sequencing technologies application discovers novel genetic alterations frequently in pediatric acute lymphoblastic leukemia (ALL). RAS signaling pathway mutations at the time of relapse ALL frequently appear as small subclones at the time of onset, which are considered as the drivers in ALL relapse. Whether subclones alterations in the RAS signaling pathway should be considered for risk group stratification of ALL treatment is not decided yet. In this work, we investigate the RAS signaling pathway mutation spectrum and the related prognosis in pediatric ALL. We employed an NGS panel comprising 220 genes. NGS results were collected from 202 pediatric ALL patients. 155 patients (76.7%) harbored at least one mutation. The incidences of RAS signaling pathway mutations are different significantly between T-ALL and B-ALL. In B-ALL, the RAS pathway is mostly involved, and NRAS (17.6%), KRAS (22.7%), and PTPN11 (7.7%) were the three most frequently mutated genes. Co-occurring mutations of CREBBP and NRAS, FLT3, or PTPN11 (p=0.002, p=0.009, and p=0.003, respectively) were found in this cohort. The 3-year RFS rates for the RAS signaling pathway mutation-positive and negative cases was 76.5 % versus 89.7 % (p=0.012). Four cases relapsed in the lately 3years were RAS signaling pathway mutation-positive. RAS signaling pathway mutation is an important biomarker for poorer relapse-free survival in pediatric B-ALL patients despite good early MRD levels.

RISK FACTORS AND EARLY SIGNS OF CRITICAL CONDITIONS IN CHILDREN WITH ACUTE LYMPHOBLASTIC LEUKEMIA ADMITTED TO THE INTENSIVE CARE UNIT

Relevance: Acute lymphoblastic leukemia (ALL) is the most common cancer among children, accounting for nearly a quarter of all childhood cancers.
 The study aimed to determine the risk factors and signs of critical conditions in children with acute lymphoblastic leukemia admitted to an intensive care unit (ICU).
 Methods: The approach used was a systematic review. Data was collected from sources published in 2019-2023. Four cohort studies, four retrospective analyses, two literature reviews, one case-control study, and one case study were included in this systematic review.
 Results: The prognosis in pediatric ALL depends on the initial number of blast cells in the peripheral blood. Patients with B-cell precursor acute lymphoblastic leukemia (BCP ALL) and low blast cell numbers survived better than patients with T-cell acute lymphoblastic leukemia (T-ALL) and low cell count. IL1B and NLRP1 genetic polymorphisms enhanced ALL risk and reduced infectious comorbidity. However, these gene polymorphisms must be confirmed in juvenile leukemia. KRAS, FLT3, NRAS, PTPN11, KMT2D, PTEN, and NOTCH1 gene mutations affected pediatric ALL patient features and treatment results. These mutations demonstrate the relevance of genetic profiling in risk classification and tailored management. Gene variations and availability of effective medication contributed. Pediatric BCP-ALL patients with the PAX5P80R mutation had worse 5-year overall survival, higher white blood cell counts, male preponderance, and more genetic abnormalities. Pediatric BCP-ALL focused on genetic analysis and risk stratification. Children of African American and European American ancestry showed varied incidence, recurrence, and outcome rates for ALL. African American children exhibited lower incidence but greater recurrence rates and poorer prognosis than European American children.
 Conclusion: Risk factors for these patients’ admission to ICU include comorbidities, infectious diseases, hypoxia, and hemodynamic instability, as well as age and baseline white blood cell count at diagnosis.

Combined use of peripheral blood blast count and platelet count during and after induction therapy to predict prognosis in children with acute lymphoblastic leukemia.

Several studies have reported an association between the rapidity of reduction in peripheral blood blast count or recovery of normal hematopoiesis and treatment outcome during therapy in children with acute lymphoblastic leukemia (ALL). However, little is known about the impact of both of these aspects on prognosis in pediatric ALL. Accordingly, the purpose of this study was to evaluate whether the combined use of blood blast count and platelet count could predict event-free survival (EFS) and overall survival (OS) when minimal residual disease (MRD) detection was not available.A total of 419 patients aged 0 to 14 years diagnosed and treated for ALL between 2011 and 2015 were enrolled.Patients with a blast count ≥0.1 × 109/L on day 8 exhibited significantly lower survival rates than that in those with blast counts <0.1 × 109/L. The EFS and OS in patients with platelet count ≥100 × 109/L on day 33 were significantly higher than those with platelet counts <100 × 109/L. In univariate and multivariate analyses, patients with low blast count on day 8 and high platelet count on day 33 were significantly associated with better EFS and OS. The combination of blast cell count on day 8 and platelet count on day 33 demonstrated a strong association with MRD-based risk stratification.Complete blood count is an inexpensive, easy to perform, and reliable measurement in children with ALL. The combination of blast count and platelet count during and after induction chemotherapy was a significant and independent prognostic factor for treatment outcome in pediatric ALL.

Upregulation of the proto-oncogene Bmi-1 predicts a poor prognosis in pediatric acute lymphoblastic leukemia

BackgroundBmi-1, the B cell-specific moloney murine leukemia virus insertion site 1, is a member of the Polycomb-group (PcG) family and acts as an oncogene in various tumors; however, its expression related to the prognosis of pediatric patients with acute lymphoblastic leukemia (ALL) has not been well studied.MethodsThe Bmi-1 expression levels in the bone marrow of 104 pediatric ALL patients and 18 normal control subjects were determined by using qRT-PCR. The association between the Bmi-1 expression and the clinicopathological characteristics of pediatric ALL patients was analyzed, and the correlation between Bmi-1 and the prognosis of pediatric ALL was calculated according to the Kaplan–Meier method. Furthermore, the association between Bmi-1 expression and its transcriptional regulator Sall4 was investigated.ResultsCompared to normal control subjects, patients with primary pediatric ALL exhibited upregulated levels of Bmi-1. However, these levels were sharply decreased in patients who achieved complete remission. A significant positive association between elevated Bmi-1 levels and a poor response to prednisone as well as an increased clinical risk was observed. Patients who overexpressed Bmi-1 at the time of diagnosis had a lower relapse-free survival (RFS) rate (75.8%), whereas patients with lower Bmi-1 expression had an RFS of 94.1%. Furthermore, in ALL patients, the mRNA expression of Bmi-1 was positively correlated to the mRNA expression of Sall4a.ConclusionsTaken together, these data suggest that Bmi-1 could serve as a novel prognostic biomarker in pediatric primary ALL and may be partially regulated by Sall4a. Our study also showed that Bmi-1 could serve as a new therapeutic target for the treatment of pediatric ALL.

Genetic Abnormalities and Prognosis in Pediatric B–precursor Acute Lymphoblastic Leukemia Treated on Tokyo Children′s Cancer Study Group Protocol

Introduction; Acute lymphoblastic leukemia (ALL) is the most common cancer in children. Most childhood cases of B-precursor ALL (BCP-ALL) may be subclassified by the presence of either gross or submicroscopic genetic alteration. Recent genomewide analyses have identified genetic or cytogenetic subtypes, such as Ph-like ALL, deletion of ERG, intrachromosomal amplification of chromosome 21 (iAMP21) in BCP-ALL. Deletion of ERG and iAMP21 were associated with frequent IKZF1 deletions, which were found in Ph-like ALL associated with poor prognosis. However, the frequency and prognostic implications of these genomic abnormalities have not been defined in Japan.Patients and Methods; We studied 208 children with de novo BCP-ALL enrolled on Tokyo Children Cancer Study Group (TCCSG) ALL L0416 and L0616 trials. All patients had a diagnosis of BCP-ALL without BCR-ABL1 phenotype confirmed by morphology, immunophenotyping and mRNA Real-time PCR. Alterations of ERG and iAMP21 were examined by Multiplex Ligation-dependent Probe Amplification (MLPA) kit P327-B1. To identify Ph-like ALL and BCR-ABL1 like ALL, We investigated gene expression of 235 BCP-ALL cases enrolled on TCCSG L0416 and L0616 trials by microarray GeneChip Human Genome U133 Plus 2.0 and analyzed using clustering analysis as described previously. To assess whether these genomic alterations overlap with known gene abnormalities, such as mutations of CRLF2,JAK1, JAK2 and IL7R, rearrangement of P2RY8-CRLF2, PAX5-JAK2 and PDGFRB-EBF1 genes and copy number alteration of IKZF1, CDKN2A/2B, PAX5, EBF1 and SH2B3 genes, mutational analyses of these genes were also performed using direct sequencing, RT-PCR or MLPA kit P335-A1 and P200.Results; We identified Ph-like signature in 9 (3.8%) patients and BCR-ABL1 like ALL signature in 11 (4.7%) patients. Five (55.6%) of 9 Ph-like ALL patients and 3 (27.3%) of 11 BCR-ABL1 like ALL patients have IKZF1 deletions. Five patients were classified into both Ph-like ALL and BCR-ABL1 like ALL. Among these 5 patients, one patient had CRLF2 high expression, JAK2 R683S/R683G mutation, CDKN2A/2B deletion and EBF1 deletion, and another patient have PAX5-JAK2 rearrangement. These two patients relapsed, and the latter patient died. Three of 9 Ph-like ALL patients relapsed and 2 died, while 7 of 11 BCR-ABL1 like ALL patients relapsed and 2 died. We identified iAMP21 in 5 (2.4%) patients and deletion of ERG in 8 (3.8%). One of 5 patients with iAMP21 and 3 of 8 patients with ERG deletion had IKZF1 deletion. One patient with iAMP21 had BCR-ABL1 like ALL signature, but not Ph-like ALL signature. CRLF2 high expression was identified in two of 5 patients with iAMP21, and P2RY8-CRLF2 rearrangement and SH2B3 deletion was identified in one of them. No mutations of CRLF2 and JAK2 were identified in patients with iAMP21 and ERG deletion. Among 5 iAMP21 patients, patient with BCR-ALB1 signature and IKZF1 deletion relapsed, and one patient died. No patients with ERG deletion relapsed or died.Conclusions; Using GeneChip microarray analysis, low frequency of Ph-like ALL signature and BCR-ABL1 like ALL signature was found. Using MLPA as a novel screenings technique, frequency of iAMP21 and ERG deletion in pediatric BCP-ALL was similar to that of previous studies. BCR-ABL1 like ALL and iAMP21 was associated poor prognosis, while ERG deletion was associated good prognosis in pediatric ALL. These data suggest that screening for these genetic abnormalities in pediatric patients with BCP-ALL is critical not only for outcome prediction but also for risk-adapted therapy. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Accumulation Of Gene Alterations Of TP53, Crebbp and IKZF1 Is a Prognostic Factor In Adult Acute Lymphoblastic Leukemia

▪ AimsMutations of the genes associating with cell differentiation or proliferation are recognized as factors of tumorigenesis or prognosis in hematological malignancies. In pediatric acute lymphoblastic leukemia (ALL), alterations of IKZF1 (a factor of lymphocyte differentiation), TP53 (a cell cycle regulator) and CREBBP (a histone modifier) are found as possible prognostic markers for stratification of treatments. On the other hand, in adult ALL, clinical significance of such alterations remains to be determined. In the present work, we examined whether the mutations in those genes affected the incidence and prognosis in adult ALL patients. MethodsWe investigated 87 adult patients with newly diagnosed ALL treated with JALSG protocols between 1986 and 2011. Age ranged from 15 to 86 years, with a median of 51 years. We obtained cDNA and genomic DNA from the peripheral blood or bone marrow mononuclear cells at diagnosis. CREBBP mutations are dominantly identified in the histone acetyltransferase (HAT) domain. HAT domain in the CREBBP gene was amplified by PCR using cDNA and was subjected to direct sequencing. Additionally other histone modifiers, EZH2, EED, and UTX, were sequenced as the same as in CREBBP. TP53 exons 5 – 8 and 10, in which mutations were commonly reported, were sequenced using genomic DNA. We amplified IKZF1 using RT-PCR for detecting aberrant dominant negative isoforms: Ik6 and Ik10. Genomic deletions of IKZF1 were assessed with RQ-PCR or genomic DNA PCR. We compared clinical profiles between patients with and without such gene mutations. The present study was approved by the Institutional Review Boards and informed consent was obtained from each patient according to guidelines based on the revised Declaration of Helsinki. ResultsIn 87 adult patients with ALL, alterations of CREBBP, EED, TP53 and IKZF1 were detected in 7 (9.5%), 3 (4.8%), 6 (6.9%) and 42 (50%), respectively. None of EZH2 and UTX mutation was found. The alterations of CREBBP and IKZF1 at diagnosis in adult patients were more frequent than those in pediatric patients ever reported. Some gene mutations were not found frequently. Each gene mutation per se did not significantly affect prognosis. We tried to predict the prognosis by scoring gene mutations and chromosomal abnormalities. Philadelphia chromosome (Ph) has great impact to prognosis of patients with ALL. We scored the number of mutated genes and Ph for each patient. As the score was higher, adult patients with ALL had poorer relapse-free survival (P=0.0439) and OS (P=0.4819), but statistical significance was not detected in this small cohort. Conclusions and DiscussionSingle gene mutations, such as IKZF1, can predict the prognosis in pediatric ALL. In adult ALL, however, only few gene mutations are reported to be promising prognostic factors which have impacts to treatment outcomes. Scoring system may be a useful method for predicting prognosis and stratifying treatment in adult ALL. Our study implies the possibility that a variety and heterogeneity of genetic alterations in adult ALL are associated with the pathogenesis for treatment resistance and prognostic marker of adult ALL. Disclosures:No relevant conflicts of interest to declare.

Prednisolone Resistance in Pediatric Acute Lymphoblastic Leukemia Can Be Synergistically Overcome by Inhibition of Anti-Apoptotic MCL1 and Glycolysis

AbstractAbstract 3528 Background:Unsuccessful treatment of pediatric precursor B acute lymphoblastic leukemia (ALL) can be ascribed to cellular resistance to antileukemic drugs. In particular, resistance towards prednisolone is associated with poor prognosis in pediatric ALL. For three reasons, we hypothesized that anti-apoptosis sustained by the BCL2 family member MCL1 and glycolysis are linked processes and concomitantly induce resistance to prednisolone: 1) Glycolysis and apoptosis are closely related survival pathways both associated with prednisolone resistance, 2) Increased glucose metabolism has been directly linked to MCL1 stabilization and attenuation of apoptosis, and 3) BCL2 family members can adjust oxidative phosphorylation, a process that together with anaerobic glycolysis, is responsible for cellular respiration and ATP production. In this study, we functionally determined the synergistic contribution of MCL1 and glycolysis to prednisolone resistance in childhood ALL. Methods:Leukemic cells of pediatric ALL patients, >90% blasts, were treated in vitro with prednisolone for 48 hours. Changes in MCL1 protein levels were measured by reverse phase protein array. MCL1 knockdown was achieved by locked nucleic acid oligonucleotides (LNAs) and lentiviral silencing in two different prednisolone resistant leukemic cell lines, and the effect was assessed with RTQ-PCR and Western blot. Cell viability and cell count were analyzed by MACSQuant. Glucose consumption was measured using the GAGO20 glucose assay, in which glucose is oxidized to form the spectrophotometric end-product Oxidized o-Dianisidine. 2-deoxyglucose (2DG) was used to inhibit glycolysis. Cytotoxicity of prednisolone in leukemic cells was determined by the in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) drug-resistance assay. Sensitivity and resistance to prednisolone was assessed using previously established LC50 cut-off values, shown to be linked to the prognosis of patients. Results:MCL1 protein expression decreased by 2.9-fold after in vitro prednisolone treatment in prednisolone sensitive patients’ leukemic cells (p<0.001). In contrast, MCL1 protein expression increased in prednisolone resistant ALL patient cells by maximum 2.3-fold (p<0.01). Three MCL1 LNA oligonucleotides efficiently diminished MCL1 protein levels by 82±16% compared to MCL1 levels measured in non-silencing control cells (p<0.05). This decrease was similar to the reduction by 72±12% seen for 2 lentivirally delivered shMCL1 (p<0.05). Silencing of MCL1 decreased leukemic cell proliferation by 9-fold and sensitized leukemic cells to prednisolone by maximum 80-fold (p<0.05). MCL1 silencing by either MCL1 LNA or shMCL1 upregulated the glucose consumption of leukemic cells by 2.5-fold (p<0.05), indicating a rescue mechanism mediated by anaerobic glycolysis. Inhibition of the anaerobic glycolysis by 2-DG diminished the proliferation rate of MCL1-silenced cells by 3.9-fold compared to MCL1-silenced cells alone (p<0.05). Most importantly, the combination of 2DG and silencing of MCL1 synergistically sensitized to prednisolone by 33±16% compared to the prednisolone response of leukemic cells treated with 2DG or MCL1 LNA alone (p<0.05, n=3). Conclusion:MCL1 is a potent target to sensitize to prednisolone in pediatric ALL. However, MCL1-silenced cells increase anaerobic glycolysis to avoid prednisolone-induced apoptosis. MCL1 and glycolysis should therefore be targeted simultaneously to effectively and synergistically reverse prednisolone resistance in ALL. Disclosures:No relevant conflicts of interest to declare.

Aberrant expression of the homeobox gene CDX2 in pediatric acute lymphoblastic leukemia

AbstractMembers of the caudal (cdx) family of homeobox proteins are essential regulators of embryonic blood development in zebrafish. Previously, we reported that the murine homologues (Cdx1, Cdx2, and Cdx4) affect formation and differentiation of embryonic stem cell (ESC)–derived hematopoietic progenitor cells. Consistent with the notion that embryonic pathways can reactivate during adult oncogenesis, recent studies suggest involvement of CDX2 in human acute myeloid leukemia (AML). Here we study CDX2 in healthy and leukemic human lymphoid cells, and show that a majority of leukemic samples display various degrees of aberrant CDX2 expression. Analysis of a cohort of 37 childhood acute lymphoblastic leukemia (ALL) patients treated in our hospital reveals that high CDX2 expression levels at diagnosis correlate with persistence of minimal residual disease (MRD) during the course of treatment. Thus, CDX2 expression levels may serve as a marker for adverse prognosis in pediatric ALL.

Genetic Profiling of Adult Acute Lymphoblastic Leukemia Cells by Single Nucleotide Polymorphism Oligonucleotide Microarray.

Acute lymphoblastic leukemia (ALL) is a malignant disease of bone marrow cells, resulting from accumulation of genetic alterations of these cells. We analyzed 74 adult ALL samples by single-nucleotide polymorphism DNA microarray (SNP-Chip) using the new algorithm AsCNAR (allele-specific copy-number analysis using anonymous references). 71 samples (96%) showed genomic abnormalities in a mean 4.5 chromosomes including duplications, deletions and loss of heterozygosity with normal copy number [we call this uniparental disomy (UPD)]. About 25% of samples had a normal karyotype but each had genomic changes detectable by SNP-Chip. Importantly, 21 cases (28%) had UPD, and 29% of these had 9p UPD. Other genomic defects included deletions of p16INK4A in 18 cases (24%), deletions of ETV6 in 7 cases (9%), and hyperdiploidy (>50 chromosomes) in 3 cases (4%). In contrast, we also analyzed 399 pediatric ALL samples and deletions occurred in p16INK4A (28%) and ETV6 (22%) and 29% cases had hyperdiploidy. Hyperdiploidy is associated with a good prognosis and occured much more frequency in pediatric ALL (29%) than adult ALL (4%) which may in part explain the better prognosis in pediatric ALL compared to adult ALL. Also, small copy number changes were detected in adult ALL including deletion of B-cell differentiation genes: EBF (4 cases, 5%), Pax5 (5 cases, 7%) and IKZF (Ikaros) (8 cases, 11%), as well as, deletion of miR-15a and miR-16-1 (2 cases, 3%), which is often found in CLL. Amplification of Rel and BCL11A occurred in one case and amplification of Akt2 occurred in another case. Moreover, we found PAX5/ETV6 fusion in one case (1%); in comparison, 14 of 399 pediatric ALL cases (4%) had PAX5 fusion genes. In summary, we discovered hidden abnormalities including small copy number change and UPD in adult ALL and identified differences between adult and pediatric ALLs. In the future, routine SNP-Chip analysis may provide novel subclassification criteria for ALL and identify unique therapeutic targets.