Search

•Among NCI high-risk patients, 93% with ETV6::RUNX1and 54% with hyperdiploid B-ALL had excellent outcomes with low-intensity therapy.•NCI high-risk patients with hyperdiploid B-ALL and slow early MRD response had worse outcomes and, therefore, require new approaches.

Limited prognostic factors have been associated with overall survival (OS) post-relapse in childhood Acute Lymphoblastic Leukemia (ALL). Patients enrolled on 12 Children’s Oncology Group frontline ALL trials (1996–2014) were analyzed to assess for additional prognostic factors associated with OS post-relapse. Among 16,115 patients, 2053 (12.7%) relapsed. Relapse rates were similar for B-ALL (12.5%) and T-ALL (11.2%) while higher for infants (34.2%). Approximately 50% of B-ALL relapses occurred late (≥36 months) and 72.5% involved the marrow. Conversely, 64.8% of T-ALL relapses occurred early (<18 months) and 47.1% involved the central nervous system. The 5-year OS post-relapse for the entire cohort was 48.9 ± 1.2%; B-ALL:52.5 ± 1.3%, T-ALL:35.5 ± 3.3%, and infant ALL:21.5 ± 3.9%. OS varied by early, intermediate and late time-to-relapse; 25.8 ± 2.4%, 49.5 ± 2.2%, and 66.4 ± 1.8% respectively for B-ALL and 29.8 ± 3.9%, 33.3 ± 7.6%, 58 ± 9.8% for T-ALL. Patients with ETV6::RUNX1or Trisomy 4 + 10 had median time-to-relapse of 43 months and higher OS post-relapse 74.4 ± 3.1% and 70.2 ± 3.6%, respectively. Patients with hypodiploidy, KMT2A-rearrangement, and TCF3::PBX1had short median time-to-relapse (12.5-18 months) and poor OS post-relapse (14.2 ± 6.1%, 31.9 ± 7.7%, 36.8 ± 6.6%). Site-of-relapse varied by cytogenetic subtype. This large dataset provided the opportunity to identify risk factors for OS post-relapse to inform trial design and highlight populations with dismal outcomes post-relapse.

The delayed intensification (DI) enhanced outcome for patients with acute lymphoblastic leukemia (ALL) treated on BFM 76/79 and CCG 105 after a prednisone-based induction. Childrens Oncology Group protocols P9904/9905 evaluated DI via a post-induction randomization for eligible National Cancer Institute (NCI) standard (SR) and high-risk (HR) patients. A second randomization compared intravenous methotrexate (IV MTX) as a 24- (1 g/m2) vs. 4-h (2 g/m2) infusion. NCI SR patients received a dexamethasone-based three-drug and NCI HR/CNS 3 SR patients a prednisone-based four-drug induction. End induction MRD (minimal residual disease) was obtained but did not impact treatment. DI improved the 10-year continuous complete remission (CCR) rate; 75.5 ± 2.5% vs. 81.8 ± 2.2% p= 0.002, whereas MTX administration did not; 4-h 80.8 ± 1.9%; 24-h 81.4 ± 1.9% (p= 0.7780). Overall survival (OS) at 10 years did not differ with DI: 91.4 ± 1.6% vs. 90.9 ± 1.7% (p= 0.25) without but was higher with the 24-h MTX infusion; 4-h 91.1 ± 1.4%; 24-h 93.9 ± 1.2% (p= 0.0209). MRD predicted outcome; 10-year CCR 87.7 ± 2.2 and 82.1 ± 2.5% when MRD was <0.01% with/without DI (p= 0.007) and 54.3 ± 8% and 44 ± 8% for patients with MRD ≥ 0.01% with/without DI (p= 0.11). DI improved CCR for patients with B-ALL with and without end induction MRD.

Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. Characterized by high levels of Native American ancestry, Hispanics are disproportionally affected by this cancer with high incidence and inferior survival. However, the genetic basis for this disparity remains poorly understood because of a paucity of genome-wide investigation of ALL in Hispanics. Performing a genome-wide association study (GWAS) in 940 Hispanic children with ALL and 681 ancestry-matched non-ALL controls, we identified a novel susceptibility locus in the ERGgene (rs2836365; P= 3.76 × 10−8; odds ratio [OR] = 1.56), with independent validation (P= .01; OR = 1.43). Imputation analyses pointed to a single causal variant driving the association signal at this locus overlapping with putative regulatory DNA elements. The effect size of the ERGrisk variant rose with increasing Native American genetic ancestry. The ERGrisk genotype was underrepresented in ALL with the ETV6-RUNX1fusion (P< .0005) but enriched in the TCF3-PBX1subtype (P< .05). Interestingly, ALL cases with germline ERGrisk alleles were significantly less likely to have somatic ERGdeletion (P< .05). Our results provide novel insights into genetic predisposition to ALL and its contribution to racial disparity in this cancer.

Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. Characterized by high levels of Native American ancestry, Hispanics are disproportionally affected by this cancer with high incidence and inferior survival. However, the genetic basis for this disparity remains poorly understood because of a paucity of genome-wide investigation of ALL in Hispanics. Performing a genome-wide association study (GWAS) in 940 Hispanic children with ALL and 681 ancestry-matched non-ALL controls, we identified a novel susceptibility locus in the ERG gene (rs2836365; P = 3.76 × 10-8; odds ratio [OR] = 1.56), with independent validation (P = .01; OR = 1.43). Imputation analyses pointed to a single causal variant driving the association signal at this locus overlapping with putative regulatory DNA elements. The effect size of the ERG risk variant rose with increasing Native American genetic ancestry. The ERG risk genotype was underrepresented in ALL with the ETV6-RUNX1 fusion (P < .0005) but enriched in the TCF3-PBX1 subtype (P < .05). Interestingly, ALL cases with germline ERG risk alleles were significantly less likely to have somatic ERG deletion (P < .05). Our results provide novel insights into genetic predisposition to ALL and its contribution to racial disparity in this cancer.

Supplemental Digital Content is available in the text.Obesity following treatment of pediatric acute lymphoblastic leukemia (ALL) has become a significant long-term concern. Excessive weight gain often occurs during treatment, particularly during induction and the first 6 months of maintenance therapy, and it may be potentially modifiable. This retrospective study aimed to evaluate the impact of an early, 3-visit nutrition intervention on weight gain during maintenance therapy in ALL patients. Medical records of the intervention group were compared with historical controls who were treated on the same ALL treatment protocols during an earlier time period. Anthropometrics were collected throughout intensive therapy and at every monthly visit during the first 12 months of maintenance therapy. In total, 67 patients were evaluated (33 in the intervention group and 34 in the control group). After controlling for significant predictors of body mass index (BMI) z-scores in maintenance therapy—including higher BMI at diagnosis and weight gain throughout intensive therapy—the intervention group demonstrated more controlled weight gain during maintenance therapy (P<0.0001). A 3-visit nutrition intervention was effective in attenuating weight gain trends during ALL maintenance therapy.

To determine the clinical significance of minimal residual disease (MRD) in patients with prognostically relevant subtypes of childhood acute lymphoblastic leukemia (ALL), we analyzed data from 488 patients treated in St Jude Total Therapy Study XV with treatment intensity based mainly on MRD levels measured during remission induction. MRD levels on day 19 predicted treatment outcome for patients with hyperdiploid >50 ALL, National Cancer Institute (NCI) standard-risk B-ALL or T-cell ALL, while MRD levels on day 46 were prognostic for patients with NCI standard-risk or high-risk B-ALL. Patients with t(12;21)/(ETV6-RUNX1) or hyperdiploidy >50 ALL had the best prognosis; those with a negative MRD on day 19 had a particularly low risk of relapse: 1.9% and 3.8%, respectively. Patients with NCI high-risk B-ALL or T-cell ALL had an inferior outcome; even with undetectable MRD on day 46, cumulative risk of relapse was 12.7% and 15.5%, respectively. Among patients with NCI standard-risk B-ALL, the outcome was intermediate overall but was poor if MRD was ⩾1% on day 19 or MRD was detectable at any level on day 46. Our results indicate that the clinical impact of MRD on treatment outcome in childhood ALL varies considerably according to leukemia subtype and time of measurement.

Asparaginase is used to treat acute lymphoblastic leukemia (ALL); however, hypersensitivity reactions can lead to suboptimal asparaginase exposure. Our objective was to use a genome-wide approach to identify loci associated with asparaginase hypersensitivity in children with ALL enrolled on St. Jude Children’s Research Hospital (SJCRH) protocols Total XIIIA (n = 154), Total XV (n = 498), and Total XVI (n = 271), or Children’s Oncology Group protocols POG 9906 (n = 222) and AALL0232 (n = 2163). Germline DNA was genotyped using the Affymetrix 500K, Affymetrix 6.0, or the Illumina Exome BeadChip array. In multivariate logistic regression, the intronic rs6021191 variant in nuclear factor of activated T cells 2 (NFATC2) had the strongest association with hypersensitivity (P = 4.1 × 10−8; odds ratio [OR] = 3.11). RNA-seq data available from 65 SJCRH ALL tumor samples and 52 Yoruba HapMap samples showed that samples carrying the rs6021191 variant had higher NFATC2 expression compared with noncarriers (P = 1.1 × 10−3 and 0.03, respectively). The top ranked nonsynonymous polymorphism was rs17885382 in HLA-DRB1 (P = 3.2 × 10−6; OR = 1.63), which is in near complete linkage disequilibrium with the HLA-DRB1*07:01 allele we previously observed in a candidate gene study. The strongest risk factors for asparaginase allergy are variants within genes regulating the immune response.

Asparaginase is used to treat acute lymphoblastic leukemia (ALL); however, hypersensitivity reactions can lead to suboptimal asparaginase exposure. Our objective was to use a genome-wide approach to identify loci associated with asparaginase hypersensitivity in children with ALL enrolled on St. Jude Children's Research Hospital (SJCRH) protocols Total XIIIA (n = 154), Total XV (n = 498), and Total XVI (n = 271), or Children's Oncology Group protocols POG 9906 (n = 222) and AALL0232 (n = 2163). Germline DNA was genotyped using the Affymetrix 500K, Affymetrix 6.0, or the Illumina Exome BeadChip array. In multivariate logistic regression, the intronic rs6021191 variant in nuclear factor of activated T cells 2 (NFATC2) had the strongest association with hypersensitivity (P= 4.1 × 10−8; odds ratio [OR] = 3.11). RNA-seq data available from 65 SJCRH ALL tumor samples and 52 Yoruba HapMap samples showed that samples carrying the rs6021191 variant had higher NFATC2expression compared with noncarriers (P= 1.1 × 10−3and 0.03, respectively). The top ranked nonsynonymous polymorphism was rs17885382 in HLA-DRB1(P= 3.2 × 10−6; OR = 1.63), which is in near complete linkage disequilibrium with the HLA-DRB1*07:01 allele we previously observed in a candidate gene study. The strongest risk factors for asparaginase allergy are variants within genes regulating the immune response.

Asparaginase is a therapeutic enzyme used to treat leukemia and lymphoma, with immune responses resulting in suboptimal drug exposure and a greater risk of relapse. To elucidate whether there is a genetic component to the mechanism of asparaginase-induced immune responses, we imputed human leukocyte antigen (HLA) alleles in patients of European ancestry enrolled on leukemia trials at St. Jude Children’s Research Hospital (n = 541) and the Children’s Oncology Group (n = 1329). We identified a higher incidence of hypersensitivity and anti-asparaginase antibodies in patients with HLA-DRB1*07:01 alleles (P = 7.5 × 10−5, odds ratio [OR] = 1.64; P = 1.4 × 10−5, OR = 2.92, respectively). Structural analysis revealed that high-risk amino acids were located within the binding pocket of the HLA protein, possibly affecting the interaction between asparaginase epitopes and the HLA-DRB1 protein. Using a sequence-based consensus approach, we predicted the binding affinity of HLA-DRB1 alleles for asparaginase epitopes, and patients whose HLA genetics predicted high-affinity binding had more allergy (P = 3.3 × 10−4, OR = 1.38). Our results suggest a mechanism of allergy whereby HLA-DRB1 alleles that confer high-affinity binding to asparaginase epitopes lead to a higher frequency of reactions. These trials were registered at www.clinicaltrials.gov as NCT00137111, NCT00549848, NCT00005603, and NCT00075725.

Asparaginase is a therapeutic enzyme used to treat leukemia and lymphoma, with immune responses resulting in suboptimal drug exposure and a greater risk of relapse. To elucidate whether there is a genetic component to the mechanism of asparaginase-induced immune responses, we imputed human leukocyte antigen (HLA) alleles in patients of European ancestry enrolled on leukemia trials at St. Jude Children's Research Hospital (n = 541) and the Children's Oncology Group (n = 1329). We identified a higher incidence of hypersensitivity and anti-asparaginase antibodies in patients with HLA-DRB1*07:01 alleles (P= 7.5 × 10−5, odds ratio [OR] = 1.64; P= 1.4 × 10−5, OR = 2.92, respectively). Structural analysis revealed that high-risk amino acids were located within the binding pocket of the HLA protein, possibly affecting the interaction between asparaginase epitopes and the HLA-DRB1 protein. Using a sequence-based consensus approach, we predicted the binding affinity of HLA-DRB1alleles for asparaginase epitopes, and patients whose HLA genetics predicted high-affinity binding had more allergy (P= 3.3 × 10−4, OR = 1.38). Our results suggest a mechanism of allergy whereby HLA-DRB1alleles that confer high-affinity binding to asparaginase epitopes lead to a higher frequency of reactions. These trials were registered at www.clinicaltrials.govas NCT00137111, NCT00549848, NCT00005603, and NCT00075725.

With the use of risk-directed therapy for childhood acute lymphoblastic leukemia (ALL), outcome has improved dramatically in the past 40 years. However, a substantial portion of patients, many of whom have no known risk factors, experience relapse. Taking a genome-wide approach, in the present study, we evaluated the relationships between genotypes at 444 044 single nucleotide polymorphisms (SNPs) with the risk of relapse in 2535 children with newly diagnosed ALL after adjusting for genetic ancestry and treatment regimen. We identified 134 SNPs that were reproducibly associated with ALL relapse. Of 134 relapse SNPs, 133 remained prognostic after adjusting for all known relapse risk factors, including minimal residual disease, and 111 were significant even among patients who were negative for minimal residual disease after remission induction therapy. The C allele at rs7142143 in the PYGL gene was associated with 3.6-fold higher risk of relapse than the T allele (P = 6.7 × 10−9). Fourteen of the 134 relapse SNPs, including variants in PDE4B and ABCB1, were also associated with antileukemic drug pharmacokinetics and/or pharmacodynamics. In the present study, we systematically identified host genetic variations related to treatment outcome of childhood ALL, most of which were prognostic independent of known risk factors for relapse, and some of which also influenced outcome by affecting host dis-position of antileukemic drugs. All trials are registered at www.clinicaltrials.gov or www.cancer.gov (COG P9904: NCT00005585; COG P9905: NCT00005596; COG P9906: NCT00005603; St Jude Total XIIIB: NCI-T93-0101D; and St Jude Total XV: NCT00137111).

With the use of risk-directed therapy for childhood acute lymphoblastic leukemia (ALL), outcome has improved dramatically in the past 40 years. However, a substantial portion of patients, many of whom have no known risk factors, experience relapse. Taking a genome-wide approach, in the present study, we evaluated the relationships between genotypes at 444 044 single nucleotide polymorphisms (SNPs) with the risk of relapse in 2535 children with newly diagnosed ALL after adjusting for genetic ancestry and treatment regimen. We identified 134 SNPs that were reproducibly associated with ALL relapse. Of 134 relapse SNPs, 133 remained prognostic after adjusting for all known relapse risk factors, including minimal residual disease, and 111 were significant even among patients who were negative for minimal residual disease after remission induction therapy. The C allele at rs7142143 in the PYGLgene was associated with 3.6-fold higher risk of relapse than the T allele (P= 6.7 × 10−9). Fourteen of the 134 relapse SNPs, including variants in PDE4Band ABCB1, were also associated with antileukemic drug pharmacokinetics and/or pharmacodynamics. In the present study, we systematically identified host genetic variations related to treatment outcome of childhood ALL, most of which were prognostic independent of known risk factors for relapse, and some of which also influenced outcome by affecting host dis-position of antileukemic drugs. All trials are registered at www.clinicaltrials.govor www.cancer.gov(COG P9904: NCT00005585; COG P9905: NCT00005596; COG P9906: NCT00005603; St Jude Total XIIIB: NCI-T93-0101D; and St Jude Total XV: NCT00137111).

The US Military has served in some of the most austere locations in the world. In this ever-changing environment, units are organized into smaller elements operating in very remote areas. This often results in longer evacuation times, which can lead to a delay in pain management if treatment is not initiated in the prehospital setting. Early pain control has become an increasingly crucial military prehospital task and must be controlled from the pain-initiating event. The individual services developed their standardized trauma training based on the recommendations by Frank Butler and the Defense Health Board Committee on Tactical Combat Casualty Care. This training stresses evidence-based treatment modalities, including pain control, derived from casualty injury analysis. Inadequate early pain control may lead to multiple acute and potentially chronic effects. These effects encompass a wide range from changes in blood pressure to delayed wound healing and posttraumatic stress disorder. Therefore, it is essential that pain be addressed in the prehospital environment.

As controversy exists regarding the prognostic significance of genomic rearrangements of CRLF2 in pediatric B-precursor acute lymphoblastic leukemia (ALL) classified as standard/intermediate-risk (SR) or high-risk (HR), we assessed the prognostic significance of CRLF2 mRNA expression, CRLF2 genomic lesions (IGH@-CRLF2, P2RY8-CRLF2, CRLF2 F232C), deletion/mutation in genes frequently associated with high CRLF2 expression (IKZF1, JAK, IL7R), and minimal residual disease (MRD) in 1061 pediatric ALL patients (499 HR and 562 SR) on COG Trials P9905/P9906. Whereas very high CRLF2 expression was found in 17.5% of cases, only 51.4% of high CRLF2 expressors had CRLF2 genomic lesions. The mechanism underlying elevated CRLF2 expression in cases lacking known genomic lesions remains to be determined. All CRLF2 genomic lesions and virtually all JAK mutations were found in high CRLF2 expressors, whereas IKZF1 deletions/mutations were distributed across the full cohort. In multivariate analyses, NCI risk group, MRD, high CRLF2 expression, and IKZF1 lesions were associated with relapse-free survival. Within HR ALL, only MRD and CRLF2 expression predicted a poorer relapse-free survival; no difference was seen between cases with or without CRLF2 genomic lesions. Thus, high CRLF2 expression is associated with a very poor outcome in high-risk, but not standard-risk, ALL. This study is registered at www.clinicaltrials.gov as NCT00005596 and NCT00005603.

As controversy exists regarding the prognostic significance of genomic rearrangements of CRLF2in pediatric B-precursor acute lymphoblastic leukemia (ALL) classified as standard/intermediate-risk (SR) or high-risk (HR), we assessed the prognostic significance of CRLF2mRNA expression, CRLF2genomic lesions (IGH@-CRLF2, P2RY8-CRLF2, CRLF2F232C), deletion/mutation in genes frequently associated with high CRLF2expression (IKZF1, JAK, IL7R), and minimal residual disease (MRD) in 1061 pediatric ALL patients (499 HR and 562 SR) on COG Trials P9905/P9906. Whereas very high CRLF2expression was found in 17.5% of cases, only 51.4% of high CRLF2expressors had CRLF2genomic lesions. The mechanism underlying elevated CRLF2expression in cases lacking known genomic lesions remains to be determined. All CRLF2genomic lesions and virtually all JAKmutations were found in high CRLF2expressors, whereas IKZF1deletions/mutations were distributed across the full cohort. In multivariate analyses, NCI risk group, MRD, high CRLF2expression, and IKZF1lesions were associated with relapse-free survival. Within HR ALL, only MRD and CRLF2expression predicted a poorer relapse-free survival; no difference was seen between cases with or without CRLF2genomic lesions. Thus, high CRLF2expression is associated with a very poor outcome in high-risk, but not standard-risk, ALL. This study is registered at www.clinicaltrials.govas NCT00005596 and NCT00005603.

We have previously hypothesized that higher systemic exposure to asparaginase may cause increased exposure to dexamethasone, both critical chemotherapeutic agents for acute lymphoblastic leukemia. Whether interpatient pharmaco-kinetic differences in dexamethasone contribute to relapse risk has never been studied. The impact of plasma clearance of dexamethasone and anti–asparaginase antibody levels on risk of relapse was assessed in 410 children who were treated on a front-line clinical trial for acute lymphoblastic leukemia and were evaluable for all pharmacologic measures, using multivariate analyses, adjusting for standard clinical and biologic prognostic factors. Dexamethasone clearance (mean ± SD) was higher (P = 3 × 10−8) in patients whose sera was positive (17.7 ± 18.6 L/h per m2) versus nega-tive (10.6 ± 5.99 L/h per m2) for anti–asparaginase antibodies. In multivariate analyses, higher dexamethasone clearance was associated with a higher risk of any relapse (P = .01) and of central nervous system relapse (P = .014). Central nervous system relapse was also more common in patients with anti–asparaginase antibodies (P = .019). In conclusion, systemic clearance of dexamethasone is higher in patients with anti–asparaginase antibodies. Lower exposure to both drugs was associated with an increased risk of relapse.

We have previously hypothesized that higher systemic exposure to asparaginase may cause increased exposure to dexamethasone, both critical chemotherapeutic agents for acute lymphoblastic leukemia. Whether interpatient pharmaco-kinetic differences in dexamethasone contribute to relapse risk has never been studied. The impact of plasma clearance of dexamethasone and anti–asparaginase antibody levels on risk of relapse was assessed in 410 children who were treated on a front-line clinical trial for acute lymphoblastic leukemia and were evaluable for all pharmacologic measures, using multivariate analyses, adjusting for standard clinical and biologic prognostic factors. Dexamethasone clearance (mean ± SD) was higher (P= 3 × 10−8) in patients whose sera was positive (17.7 ± 18.6 L/h per m2) versus nega-tive (10.6 ± 5.99 L/h per m2) for anti–asparaginase antibodies. In multivariate analyses, higher dexamethasone clearance was associated with a higher risk of any relapse (P= .01) and of central nervous system relapse (P= .014). Central nervous system relapse was also more common in patients with anti–asparaginase antibodies (P= .019). In conclusion, systemic clearance of dexamethasone is higher in patients with anti–asparaginase antibodies. Lower exposure to both drugs was associated with an increased risk of relapse.

We sequenced 120 candidate genes in 187 high-risk childhood B-precursor acute lymphoblastic leukemias, the largest pediatric cancer genome sequencing effort reported to date. Integrated analysis of 179 validated somatic sequence mutations with genome-wide copy number alterations and gene expression profiles revealed a high frequency of recurrent somatic alterations in key signaling pathways, including B-cell development/differentiation (68% of cases), the TP53/RB tumor suppressor pathway (54%), Ras signaling (50%), and Janus kinases (11%). Recurrent mutations were also found in ETV6(6 cases), TBL1XR1(3), CREBBP(3), MUC4(2), ASMTL(2), and ADARB2(2). The frequency of mutations within the 4 major pathways varied markedly across genetic subtypes. Among 23 leukemias expressing a BCR-ABL1-like gene expression profile, 96% had somatic alterations in B-cell development/differentiation, 57% in JAK, and 52% in both pathways, whereas only 9% had Ras pathway mutations. In contrast, 21 cases defined by a distinct gene expression profile coupled with focal ERGdeletion rarely had B-cell development/differentiation or JAK kinase alterations but had a high frequency (62%) of Ras signaling pathway mutations. These data extend the range of genes that are recurrently mutated in high-risk childhood B-precursor acute lymphoblastic leukemia and highlight important new therapeutic targets for selected patient subsets.

We sequenced 120 candidate genes in 187 high-risk childhood B-precursor acute lymphoblastic leukemias, the largest pediatric cancer genome sequencing effort reported to date. Integrated analysis of 179 validated somatic sequence mutations with genome-wide copy number alterations and gene expression profiles revealed a high frequency of recurrent somatic alterations in key signaling pathways, including B-cell development/differentiation (68% of cases), the TP53/RB tumor suppressor pathway (54%), Ras signaling (50%), and Janus kinases (11%). Recurrent mutations were also found in ETV6 (6 cases), TBL1XR1 (3), CREBBP (3), MUC4 (2), ASMTL (2), and ADARB2 (2). The frequency of mutations within the 4 major pathways varied markedly across genetic subtypes. Among 23 leukemias expressing a BCR-ABL1-like gene expression profile, 96% had somatic alterations in B-cell development/differentiation, 57% in JAK, and 52% in both pathways, whereas only 9% had Ras pathway mutations. In contrast, 21 cases defined by a distinct gene expression profile coupled with focal ERG deletion rarely had B-cell development/differentiation or JAK kinase alterations but had a high frequency (62%) of Ras signaling pathway mutations. These data extend the range of genes that are recurrently mutated in high-risk childhood B-precursor acute lymphoblastic leukemia and highlight important new therapeutic targets for selected patient subsets.

To resolve the genetic heterogeneity within pediatric high-risk B-precursor acute lymphoblastic leukemia (ALL), a clinically defined poor-risk group with few known recurring cytogenetic abnormalities, we performed gene expression profiling in a cohort of 207 uniformly treated children with high-risk ALL. Expression profiles were correlated with genome-wide DNA copy number abnormalities and clinical and outcome features. Unsupervised clustering of gene expression profiling data revealed 8 unique cluster groups within these high-risk ALL patients, 2 of which were associated with known chromosomal translocations (t(1;19)(TCF3-PBX1) or MLL), and 6 of which lacked any previously known cytogenetic lesion. One unique cluster was characterized by high expression of distinct outlier genes AGAP1, CCNJ, CHST2/7, CLEC12A/B, and PTPRM; ERG DNA deletions; and 4-year relapse-free survival of 94.7% ± 5.1%, compared with 63.5% ± 3.7% for the cohort (P = .01). A second cluster, characterized by high expression of BMPR1B, CRLF2, GPR110, and MUC4; frequent deletion of EBF1, IKZF1, RAG1-2, and IL3RA-CSF2RA; JAK mutations and CRLF2 rearrangements (P < .0001); and Hispanic ethnicity (P < .001) had a very poor 4-year relapse-free survival (21.0% ± 9.5%; P < .001). These studies reveal striking clinical and genetic heterogeneity in high-risk ALL and point to novel genes that may serve as new targets for diagnosis, risk classification, and therapy.

To resolve the genetic heterogeneity within pediatric high-risk B-precursor acute lymphoblastic leukemia (ALL), a clinically defined poor-risk group with few known recurring cytogenetic abnormalities, we performed gene expression profiling in a cohort of 207 uniformly treated children with high-risk ALL. Expression profiles were correlated with genome-wide DNA copy number abnormalities and clinical and outcome features. Unsupervised clustering of gene expression profiling data revealed 8 unique cluster groups within these high-risk ALL patients, 2 of which were associated with known chromosomal translocations (t(1;19)(TCF3-PBX1) or MLL), and 6 of which lacked any previously known cytogenetic lesion. One unique cluster was characterized by high expression of distinct outlier genes AGAP1, CCNJ, CHST2/7, CLEC12A/B, and PTPRM; ERGDNA deletions; and 4-year relapse-free survival of 94.7% ± 5.1%, compared with 63.5% ± 3.7% for the cohort (P= .01). A second cluster, characterized by high expression of BMPR1B, CRLF2, GPR110, and MUC4; frequent deletion of EBF1, IKZF1, RAG1-2, and IL3RA-CSF2RA; JAKmutations and CRLF2rearrangements (P< .0001); and Hispanic ethnicity (P< .001) had a very poor 4-year relapse-free survival (21.0% ± 9.5%; P< .001). These studies reveal striking clinical and genetic heterogeneity in high-risk ALL and point to novel genes that may serve as new targets for diagnosis, risk classification, and therapy.

Gene expression profiling of 207 uniformly treated children with high-risk B-progenitor acute lymphoblastic leukemia revealed 29 of 207 cases (14%) with markedly elevated expression of CRLF2 (cytokine receptor-like factor 2). Each of the 29 cases harbored a genomic rearrangement of CRLF2: 18 of 29 (62%) had a translocation of the immunoglobulin heavy chain gene IGH@ on 14q32 to CRLF2 in the pseudoautosomal region 1 of Xp22.3/Yp11.3, whereas 10 (34%) cases had a 320-kb interstitial deletion centromeric of CRLF2, resulting in a P2RY8-CRLF2 fusion. One case had both IGH@-CRLF2 and P2RY8-CRLF2, and another had a novel CRLF2 rearrangement. Only 2 of 29 cases were Down syndrome. CRLF2 rearrangements were significantly associated with activating mutations of JAK1 or JAK2, deletion or mutation of IKZF1, and Hispanic/Latino ethnicity (Fisher exact test, P < .001 for each). Within this cohort, patients with CRLF2 rearrangements had extremely poor treatment outcomes compared with those without CRLF2 rearrangements (35.3% vs 71.3% relapse-free survival at 4 years; P < .001). Together, these observations suggest that activation of CRLF2 expression, mutation of JAK kinases, and alterations of IKZF1 cooperate to promote B-cell leukemogenesis and identify these pathways as important therapeutic targets in this disease. This trial was registered at www.clinicaltrials.gov as #NCT00005603.

Gene expression profiling of 207 uniformly treated children with high-risk B-progenitor acute lymphoblastic leukemia revealed 29 of 207 cases (14%) with markedly elevated expression of CRLF2(cytokine receptor-like factor 2). Each of the 29 cases harbored a genomic rearrangement of CRLF2: 18 of 29 (62%) had a translocation of the immunoglobulin heavy chain gene IGH@ on 14q32 to CRLF2in the pseudoautosomal region 1 of Xp22.3/Yp11.3, whereas 10 (34%) cases had a 320-kb interstitial deletion centromeric of CRLF2, resulting in a P2RY8-CRLF2fusion. One case had both IGH@-CRLF2and P2RY8-CRLF2, and another had a novel CRLF2rearrangement. Only 2 of 29 cases were Down syndrome. CRLF2rearrangements were significantly associated with activating mutations of JAK1or JAK2, deletion or mutation of IKZF1, and Hispanic/Latino ethnicity (Fisher exact test, P< .001 for each). Within this cohort, patients with CRLF2rearrangements had extremely poor treatment outcomes compared with those without CRLF2rearrangements (35.3% vs 71.3% relapse-free survival at 4 years; P< .001). Together, these observations suggest that activation of CRLF2expression, mutation of JAKkinases, and alterations of IKZF1cooperate to promote B-cell leukemogenesis and identify these pathways as important therapeutic targets in this disease. This trial was registered at www.clinicaltrials.govas #NCT00005603.

To determine whether gene expression profiling could improve outcome prediction in children with acute lymphoblastic leukemia (ALL) at high risk for relapse, we profiled pretreatment leukemic cells in 207 uniformly treated children with high-risk B-precursor ALL. A 38-gene expression classifier predictive of relapse-free survival (RFS) could distinguish 2 groups with differing relapse risks: low (4-year RFS, 81%, n = 109) versus high (4-year RFS, 50%, n = 98; P < .001). In multivariate analysis, the gene expression classifier (P = .001) and flow cytometric measures of minimal residual disease (MRD; P = .001) each provided independent prognostic information. Together, they could be used to classify children with high-risk ALL into low- (87% RFS), intermediate- (62% RFS), or high- (29% RFS) risk groups (P < .001). A 21-gene expression classifier predictive of end-induction MRD effectively substituted for flow MRD, yielding a combined classifier that could distinguish these 3 risk groups at diagnosis (P < .001). These classifiers were further validated on an independent high-risk ALL cohort (P = .006) and retainedindependent prognostic significance (P < .001) in the presence of other recently described poor prognostic factors (IKAROS/IKZF1 deletions, JAK mutations, and kinase expression signatures). Thus, gene expression classifiers improve ALL risk classification and allow prospective identification of children who respond or fail current treatment regimens. These trials were registered at http://clinicaltrials.gov under NCT00005603.

To determine whether gene expression profiling could improve outcome prediction in children with acute lymphoblastic leukemia (ALL) at high risk for relapse, we profiled pretreatment leukemic cells in 207 uniformly treated children with high-risk B-precursor ALL. A 38-gene expression classifier predictive of relapse-free survival (RFS) could distinguish 2 groups with differing relapse risks: low (4-year RFS, 81%, n = 109) versus high (4-year RFS, 50%, n = 98; P< .001). In multivariate analysis, the gene expression classifier (P= .001) and flow cytometric measures of minimal residual disease (MRD; P= .001) each provided independent prognostic information. Together, they could be used to classify children with high-risk ALL into low- (87% RFS), intermediate- (62% RFS), or high- (29% RFS) risk groups (P< .001). A 21-gene expression classifier predictive of end-induction MRD effectively substituted for flow MRD, yielding a combined classifier that could distinguish these 3 risk groups at diagnosis (P< .001). These classifiers were further validated on an independent high-risk ALL cohort (P= .006) and retainedindependent prognostic significance (P< .001) in the presence of other recently described poor prognostic factors (IKAROS/IKZF1deletions, JAKmutations, and kinase expression signatures). Thus, gene expression classifiers improve ALL risk classification and allow prospective identification of children who respond or fail current treatment regimens. These trials were registered at http://clinicaltrials.govunder NCT00005603.

Minimal residual disease (MRD) is an important predictor of relapse in acute lymphoblastic leukemia (ALL), but its relationship to other prognostic variables has not been fully assessed. The Children’s Oncology Group studied the prognostic impact of MRD measured by flow cytometry in the peripheral blood at day 8, and in end-induction (day 29) and end-consolidation marrows in 2143 children with precursor B-cell ALL (B-ALL). The presence of MRD in day-8 blood and day-29 marrow MRD was associated with shorter event-free survival (EFS) in all risk groups; even patients with 0.01% to 0.1% day-29 MRD had poor outcome compared with patients negative for MRD patients (59% ± 5% vs 88% ± 1% 5-year EFS). Presence of good prognostic markers TEL-AML1 or trisomies of chromosomes 4 and 10 still provided additional prognostic information, but not in National Cancer Insitute high-risk (NCI HR) patients who were MRD+. The few patients with detectable MRD at end of consolidation fared especially poorly, with only a 43% plus or minus 7% 5-year EFS. Day-29 marrow MRD was the most important prognostic variable in multi-variate analysis. The 12% of patients with all favorable risk factors, including NCI risk group, genetics, and absence of days 8 and 29 MRD, had a 97% plus or minus 1% 5-year EFS with nonintensive therapy. These studies are registered at www.clinicaltrials.govas NCT00005585, NCT00005596, and NCT00005603.

Minimal residual disease (MRD) is an important predictor of relapse in acute lymphoblastic leukemia (ALL), but its relationship to other prognostic variables has not been fully assessed. The Children's Oncology Group studied the prognostic impact of MRD measured by flow cytometry in the peripheral blood at day 8, and in end-induction (day 29) and end-consolidation marrows in 2143 children with precursor B-cell ALL (B-ALL). The presence of MRD in day-8 blood and day-29 marrow MRD was associated with shorter event-free survival (EFS) in all risk groups; even patients with 0.01% to 0.1% day-29 MRD had poor outcome compared with patients negative for MRD patients (59% ± 5% vs 88% ± 1% 5-year EFS). Presence of good prognostic markers TEL-AML1 or trisomies of chromosomes 4 and 10 still provided additional prognostic information, but not in National Cancer Insitute high-risk (NCI HR) patients who were MRD+. The few patients with detectable MRD at end of consolidation fared especially poorly, with only a 43% plus or minus 7% 5-year EFS. Day-29 marrow MRD was the most important prognostic variable in multi-variate analysis. The 12% of patients with all favorable risk factors, including NCI risk group, genetics, and absence of days 8 and 29 MRD, had a 97% plus or minus 1% 5-year EFS with nonintensive therapy. These studies are registered at www.clinicaltrials.gov as NCT00005585, NCT00005596, and NCT00005603.

The synthesis and full characterisation of a series of 1,2,4‐thiadiazoles is reported. (SCN)xhas been studied by a variety of techniques and the data compared with 1,2,4‐thiadiazole and 1,2,4‐dithiazoles. The observed data suggest that the polymer consists of 1,2,4‐dithiazole rings linked by nitrogen atoms. For (SCN)x, the MALDI‐TOF mass spectroscopy showed a parent ion at 1149 and a series of peaks with (SCN)2repeat units (116 m/z); this result implies that (SCN)2may be the monomer unit of the polymer. Its IR spectrum shows a very broad peak with maximum at 1134 cm−1consisting of several overlapping peaks in the same region as ring vibrations for 1,2,4‐thiadiazole and 1,2,4‐dithiazole compounds. Peaks in the Raman spectrum in the range 400–480 cm−1support the presence of disulfide units within the polymer. The solid‐state 13C NMR (99 % 13C‐labelled) spectrum is dominated by two singlets of equal intensity at approximately 187 and 184 ppm with low intensity peaks in the range 152–172 ppm, in approximately the same range as both 1,2,4‐thiadiazoles and 1,2,4‐dithiazoles. The solid‐state 15N NMR (99 % 15N labelled) spectrum displays two major peaks of similar intensity at 236.9 and 197.2 ppm, which are clearly very different environments to those observed in bis(3‐bromo‐1,2,4‐thiadiazol‐5‐yl) disulfide, but similar to 1,2,4‐dithiazoles. The X‐ray structures of seven C‐S‐N systems are reported. Preliminary studies on (SeCN)xsuggest that literature references to this polymer may be in error with the red solid actually being red selenium.

Flow cytometric analysis of minimal residual disease (MRD) depends on detecting phenotypically abnormal populations. However, little is known about how phenotypic shifts between diagnosis and relapse affect MRD detection in childhood acute lymphoid leukemia (ALL).We compared diagnostic and relapse bone marrow specimens in 42 children with precursor B‐ALL studied with the two‐tube panel CD19‐APC/CD45‐PerCP/CD10‐PE/CD20‐FITC and CD19‐APC/CD45‐PerCP/CD9‐PE/CD34‐FITC.At least 29 cases had phenotypic shifts of intensity or coefficient of variation of distribution of one or more markers. Shifts were complex and could not be explained by change in maturation stage. In the majority of cases MRD populations more closely resembled the diagnostic than the relapse specimen. In 6 of 7 MRD negative cases we did not identify an abnormal population that resembled diagnosis or relapse. In the remaining case, in which CD34 and CD10 were lost between diagnosis and relapse, it is possible that we could have missed an MRD population resembling relapse.Phenotypic shifts are common, but do not affect MRD recognition. At most 1 of 42 cases might have harbored an abnormal population undetected because of shift. However, MRD analysis with rigid gating (looking strictly for abnormal phenotypes at diagnosis) might have missed many positive cases, 8 of 22 (36%) in this series. © 2005 Wiley‐Liss, Inc.

Imidoyl radicals, generated from imidoyl phenylselanide precursors, have been used for the synthesis of 2,3-disubstituted indoles. A facile high yielding synthesis of imidoyl phenylselanides has been developed. The potential for neophyl rearrangement of 5-exo radical intermediates to 6-endo radical intermediates is discussed.

New solid phase triorganogermanium hydrides have been synthesized by the addition of a simple triorganogermanium hydride unit onto QuadragelTM and Merrifield resins. The new solid phase germanium hydrides have been used to mediate a range of synthetic radical reactions.

No Abstract

No Abstract

Juvenile ornate rock lobsters (Panulirus ornatus) (3.240.09 g; 13.80.13 mm CL) captured from the wild were stocked at three densities (14, 29, and 43 m–2) within each of four 4000-L fibreglass raceway tanks with flow-through seawater supply. Lobsters were provided with shelters consisting of opaque polyethylene platforms, 600 mm × 600 mm, supported on six 100-mm legs and were fed continually through the night with a commercial penaeid prawn (P. japonicus) pellet supplemented with prawn flesh once per day. Growth and survival were monitored by means of a monthly sample of 20 lobsters from each experimental unit. After 272 days, density treatments did not differ significantly in survival, which averaged 52.5% (2.8). Lobster size was also unaffected by density, and mean size for all lobsters was 225.34.68 g (61.84.7 mm CL) at harvest. Mortality was consistent through time and was almost entirely attributable to cannibalism of postmoult individuals. The cannibalism may have been due to inappropriate shelter and feeding strategy. Despite higher mortality than anticipated, growth was rapid, representing a specific growth rate of 1.56% day–1, sufficient to permit growth from 3 g to 1 kg within 18 months. The experiment confirmed the excellent potential of P. ornatus for commercial aquaculture.