Anthracycline-Free Protocol for Favorable-Risk Childhood ALL: A Noninferiority Comparison Between Malaysia-Singapore ALL 2003 and ALL 2010 Studies.

PURPOSE: To investigate whether, for children with favorable-risk B-cell precursor ALL (BCP-ALL), an anthracycline-free protocol is noninferior to a modified Berlin-Frankfurt-Muenster ALL-IC2002 protocol, which includes 120 mg/m2 of anthracyclines. PATIENTS AND METHODS: Three hundred sixty-nine children with favorable-risk BCP-ALL (age 1-9 years, no extramedullary disease, and no high-risk genetics) who cleared minimal residual disease (≤0.01%) at the end of remission induction were enrolled into Ma-Spore (MS) ALL trials. One hundred sixty-seven standard-risk (SR) patients (34% of Malaysia-Singapore ALL 2003 study [MS2003]) were treated with the MS2003-SR protocol and received 120 mg/m2 of anthracyclines during delayed intensification while 202 patients (42% of MS2010) received an anthracycline-free successor protocol. The primary outcome was a noninferiority margin of 1.15 in 6-year event-free survival (EFS) between the MS2003-SR and MS2010-SR cohorts. RESULTS: The 6-year EFS of MS2003-SR and MS2010-SR (anthracycline-free) cohorts was 95.2% ± 1.7% and 96.5% ± 1.5%, respectively (P = .46). The corresponding 6-year overall survival was 97.6% and 99.0% ± 0.7% (P = .81), respectively. The cumulative incidence of relapse was 3.6% and 2.6%, respectively (P = .42). After adjustment for race, sex, age, presenting WBC, day 8 prednisolone response, and favorable genetic subgroups, the hazard ratio for MS2010-SR EFS was 0.98 (95% CI, 0.84 to 1.14; P = .79), confirming noninferiority. Compared with MS2003-SR, MS2010-SR had significantly lower episodes of bacteremia (30% v 45.6%; P = .04) and intensive care unit admissions (1.5% v 9.5%; P = .004). CONCLUSION: In comparison with MS2003-SR, the anthracycline-free MS2010-SR protocol is not inferior and was less toxic as treatment for favorable-risk childhood BCP-ALL.

Association of Genetic Ancestry With the Molecular Subtypes and Prognosis of Childhood Acute Lymphoblastic Leukemia.

IMPORTANCE: Racial and ethnic disparities persist in the incidence and treatment outcomes of childhood acute lymphoblastic leukemia (ALL). However, there is a paucity of data describing the genetic basis of these disparities, especially in association with modern ALL molecular taxonomy and in the context of contemporary treatment regimens. OBJECTIVE: To evaluate the association of genetic ancestry with childhood ALL molecular subtypes and outcomes of modern ALL therapy. DESIGN, SETTING, AND PARTICIPANTS: This multinational, multicenter genetic association study was conducted from March 1, 2000, to November 20, 2020, among 2428 children and adolescents with ALL enrolled in frontline trials from the United States, South East Asia (Singapore and Malaysia), and Latin America (Guatemala), representing diverse populations of European, African, Native American, East Asian, and South Asian descent. Statistical analysis was conducted from February 3, 2020, to April 19, 2021. MAIN OUTCOMES AND MEASURES: Molecular subtypes of ALL and genetic ancestry were comprehensively characterized by performing RNA sequencing. Associations of genetic ancestries with ALL molecular subtypes and treatment outcomes were then evaluated. RESULTS: Among the participants in the study, 1340 of 2318 (57.8%) were male, and the mean (SD) age was 7.8 (5.3) years. Of 21 ALL subtypes identified, 8 were associated with ancestry. East Asian ancestry was positively associated with the frequency of somatic DUX4 (odds ratio [OR], 1.30 [95% CI, 1.16-1.45]; P < .001) and ZNF384 (OR, 1.40 [95% CI, 1.18-1.66]; P < .001) gene rearrangements and negatively associated with BCR-ABL1-like ALL (OR, 0.79 [95% CI, 0.66-0.92]; P = .002) and T-cell ALL (OR, 0.80 [95% CI, 0.71-0.90]; P < .001). By contrast, occurrence of CRLF2 rearrangements was associated with Native American ancestry (OR, 1.48 [95% CI, 1.29-1.69]; P < .001). When the percentage of Native American ancestry increased, ETV6-RUNX1 fusion became less frequent (OR, 0.80 [95% CI, 0.70-0.91]; P < .001), with the opposite trend observed for ETV6-RUNX1-like ALL. There was a marked preponderance of T-cell ALL in children of African descent compared with those with a high percentage of Native American ancestry (African: OR, 1.22 [95% CI, 1.07-1.37]; P = .003; Native American: OR, 0.53 [95% CI, 0.40-0.67]; P < .001). African ancestry was also positively associated with the prevalence of TCF3-PBX1 (OR, 1.49 [95% CI, 1.25-1.76]; P < .001) and negatively associated with DUX4 rearrangements (OR, 0.70 [95% CI, 0.48-0.93]; P = .01) and hyperdiploidy (OR, 0.77 [95% CI, 0.68-0.86]; P < .001). African and Native American ancestries as continuous variables were both associated with poorer event-free survival (for every 25% increase in ancestry: hazard ratio [HR], 1.2; 95% CI, 1.1-1.4; P = .001 for African ancestry; HR, 1.3; 95% CI, 1.0-1.6; P = .04 for Native American ancestry) and overall survival (for every 25% increase in ancestry: HR, 1.2; 95% CI, 1.1-1.5; P = .01 for African ancestry; HR, 1.4; 95% CI, 1.0-1.8; P = .03 for Native American ancestry). Even after adjusting for biological subtypes and clinical features, Native American and African ancestries remained associated with poor prognosis. CONCLUSIONS AND RELEVANCE: This study suggests that ALL molecular subtypes and prognosis are associated with genetic ancestry, potentially pointing to a genetic basis for some of the racial and ethnic disparities in ALL. Therefore, molecular subtype-driven treatment individualization is needed to help address racial and ethnic gaps in outcomes.

Distinct clinical characteristics of DUX4- and PAX5-altered childhood B-lymphoblastic leukemia.

Among the recently described subtypes in childhood B-lymphoblastic leukemia (B-ALL) were DUX4- and PAX5-altered (PAX5alt). By using whole transcriptome RNA sequencing in 377 children with B-ALL from the Malaysia-Singapore ALL 2003 (MS2003) and Malaysia-Singapore ALL 2010 (MS2010) studies, we found that, after hyperdiploid and ETV6-RUNX1, the third and fourth most common subtypes were DUX4 (n = 51; 14%) and PAX5alt (n = 36; 10%). DUX4 also formed the largest genetic subtype among patients with poor day-33 minimal residual disease (MRD; n = 12 of 44). But despite the poor MRD, outcome of DUX4 B-ALL was excellent (5-year cumulative risk of relapse [CIR], 8.9%; 95% confidence interval [CI], 2.8%-19.5% and 5-year overall survival, 97.8%; 95% CI, 85.3%-99.7%). In MS2003, 21% of patients with DUX4 B-ALL had poor peripheral blood response to prednisolone at day 8, higher than other subtypes (8%; P = .03). In MS2010, with vincristine at day 1, no day-8 poor peripheral blood response was observed in the DUX4 subtype (P = .03). The PAX5alt group had an intermediate risk of relapse (5-year CIR, 18.1%) but when IKZF1 was not deleted, outcome was excellent with no relapse among 23 patients. Compared with MS2003, outcome of PAX5alt B-ALL with IKZF1 codeletion was improved by treatment intensification in MS2010 (5-year CIR, 80.0% vs 0%; P = .05). In conclusion, despite its poor initial response, DUX4 B-ALL had a favorable overall outcome, and the prognosis of PAX5alt was strongly dependent on IKZF1 codeletion.

Intracellular vincristine levels in lymphoblasts affect treatment outcome in childhood B-lymphoblastic leukaemia: Ma-Spore ALL 2010 study.

AIMS: Vincristine (VCR) is a key drug in the successful multidrug chemotherapy for childhood acute lymphoblastic leukaemia (ALL). However, it remains unclear how VCR pharmacokinetics affects its antileukaemic efficacy. The objective of this study is to explore the VCR pharmacokinetic parameters and intracellular VCR levels in an up-front window of Ma-Spore ALL 2010 (MS2010) study. METHODS: We randomised 429 children with newly diagnosed ALL to 15-minute vs 3-hour infusion for the first dose of VCR to study if prolonging the first dose of VCR infusion improved response. In a subgroup of 115 B-ALL and 20 T-ALL patients, we performed VCR plasma (n = 135 patients) and intracellular (n = 66 patients) pharmacokinetic studies. The correlations between pharmacokinetic parameters and intracellular VCR levels with early treatment response, final outcome and ABCB1 genotypes were analysed. RESULTS: There was no significant difference between 15-minute and 3-hour infusion schedules in median Day 8 peripheral or bone marrow blast response. Plasma VCR pharmacokinetic parameters did not predict outcome. However, in B-ALL, Day 33 minimal residual disease (MRD) negative patients and patients in continuous complete remission had significantly higher median intracellular VCR24h levels (P = .03 and P = .04, respectively). The median VCR24h intracellular levels were similar among the common genetic subtypes of ALL (P = .4). Patients homozygous for wild-type ABCB1 2677GG had significantly higher median intracellular VCR24h (P = .04) than 2677TT. CONCLUSION: We showed that in childhood B-ALL, the intracellular VCR24h levels in lymphoblasts affected treatment outcomes. The intracellular VCR24h level was independent of leukaemia subtype but dependent on host ABCB1 G2677T genotype.

Identifying IGH disease clones for MRD monitoring in childhood B-cell acute lymphoblastic leukemia using RNA-Seq.

Identifying patient-specific clonal IGH/TCR junctional sequences is critical for minimal residual disease (MRD) monitoring. Conventionally these junctional sequences are identified using laborious Sanger sequencing of excised heteroduplex bands. We found that the IGH is highly expressed in our diagnostic B-cell acute lymphoblastic leukemia (B-ALL) samples using RNA-Seq. Therefore, we used RNA-Seq to identify IGH disease clone sequences in 258 childhood B-ALL samples for MRD monitoring. The amount of background IGH rearrangements uncovered by RNA-Seq followed the Zipf's law with IGH disease clones easily identified as outliers. Four hundred and ninety-seven IGH disease clones (median 2, range 0-7 clones/patient) are identified in 90.3% of patients. High hyperdiploid patients have the most IGH disease clones (median 3) while DUX4 subtype has the least (median 1) due to the rearrangements involving the IGH locus. In all, 90.8% of IGH disease clones found by Sanger sequencing are also identified by RNA-Seq. In addition, RNA-Seq identified 43% more IGH disease clones. In 69 patients lacking sensitive IGH targets, targeted NGS IGH MRD showed high correlation (R = 0.93; P = 1.3 × 10-14), better relapse prediction than conventional RQ-PCR MRD using non-IGH targets. In conclusion, RNA-Seq can identify patient-specific clonal IGH junctional sequences for MRD monitoring, adding to its usefulness for molecular diagnosis in childhood B-ALL.

Haematopoietic stem cell transplantation for inborn errors of immunity: 25-year experience from University of Malaya Medical Centre, Malaysia.

AIM: Inborn errors of immunity (IEI) comprise a heterogeneous group of disorders of the immune system, most of which are curable by haematopoietic stem cell transplantation (HSCT). We present a 25-year audit of HSCT for IEI at a tertiary-level academic hospital in Malaysia. METHODS: Review of medical records of all cases of IEI who underwent HSCT between January 1993 and December 2018 at our centre. Diagnoses, complications, HSCT protocols and outcome data were studied. RESULTS: There were 20 patients (19 boys) with a median age at diagnosis of 11 months (range: 2 months to 12 years). Eleven of 19 (58%) had malnutrition at presentation. Donor sources were variable: 13 (65%) matched sibling donor (MSD), 4 (20%) human leukocyte antigen-haploidentical donor (HD) and 3 (15%) matched unrelated donor (MUD). Conditioning regimens were physician-dependent and adapted to each patient's clinical status. Grades III-IV acute graft-versus-host disease occurred in two of three cases who received MUD grafts, 50% in those who received HD, and 8% in the MSD group. Transplant-related mortality at day +100 was 5%. With a median follow-up of 7.5 years, 18 (90%) patients are alive and free of infections. CONCLUSION: Outcome of HSCT for IEI in our centre is comparable with international reports. HSCT results using HD and MUD grafts are also good despite challenges from acute graft-versus-host disease, providing a feasible alternative for patients without matched donors.

Intensifying Treatment of Childhood B-Lymphoblastic Leukemia With IKZF1 Deletion Reduces Relapse and Improves Overall Survival: Results of Malaysia-Singapore ALL 2010 Study.

Purpose Although IKZF1 deletion ( IKZF1del) confers a higher risk of relapse in childhood B-cell acute lymphoblastic leukemia (B-ALL), it is uncertain whether treatment intensification will reverse this risk and improve outcomes. The Malaysia-Singapore ALL 2010 study (MS2010) prospectively upgraded the risk assignment of patients with IKZF1del to the next highest level and added imatinib to the treatment of all patients with BCR- ABL1 fusion. Patients and Methods In total, 823 patients with B-ALL treated in the Malyasia-Singapore ALL 2003 study (MS2003; n = 507) and MS2010 (n = 316) were screened for IKZF1del using the multiplex ligation-dependent probe amplification assay. The impact of IKZF1del on the 5-year cumulative incidence of relapse (CIR) was compared between the two studies. Results Patient characteristics were similar in both cohorts, including IKZF1del frequencies (59 of 410 [14.4%] v 50 of 275 [18.2%]; P = .2). In MS2003, where IKZF1del was not used in risk assignment, IKZF1del conferred a significantly higher 5-year CIR (30.4% v 8.1%; P = 8.7 × 10-7), particularly in the intermediate-risk group who lacked high-risk features (25.0% v 7.5%; P = .01). For patients with BCR-ABL1-negative disease, IKZF1del conferred a higher 5-year CIR (20.5% v 8.0%; P = .01). In MS2010, the 5-year CIR of patients with IKZF1del significantly decreased to 13.5% ( P = .05) and no longer showed a significant difference in patients with BCR-ABL1-negative disease (11.4% v 4.4%; P = .09). The 5-year overall survival for patients with IKZF1del improved from 69.6% in MS2003 to 91.6% in MS2010 ( P = .007). Conclusion Intensifying therapy for childhood B-ALL with IKZF1del significantly reduced the risk of relapse and improved overall survival. Incorporating IKZF1del screening significantly improved treatment outcomes in contemporary ALL therapy.

Effective Response Metric: a novel tool to predict relapse in childhood acute lymphoblastic leukaemia using time-series gene expression profiling.

Accurate risk assignment in childhood acute lymphoblastic leukaemia is essential to avoid under- or over-treatment. We hypothesized that time-series gene expression profiles (GEPs) of bone marrow samples during remission-induction therapy can measure the response and be used for relapse prediction. We computed the time-series changes from diagnosis to Day 8 of remission-induction, termed Effective Response Metric (ERM-D8) and tested its ability to predict relapse against contemporary risk assignment methods, including National Cancer Institutes (NCI) criteria, genetics and minimal residual disease (MRD). ERM-D8 was trained on a set of 131 patients and validated on an independent set of 79 patients. In the independent blinded test set, unfavourable ERM-D8 patients had >3-fold increased risk of relapse compared to favourable ERM-D8 (5-year cumulative incidence of relapse 38·1% vs. 10·6%; P = 2·5 × 10-3 ). ERM-D8 remained predictive of relapse [P = 0·05; Hazard ratio 4·09, 95% confidence interval (CI) 1·03-16·23] after adjusting for NCI criteria, genetics, Day 8 peripheral response and Day 33 MRD. ERM-D8 improved risk stratification in favourable genetics subgroups (P = 0·01) and Day 33 MRD positive patients (P = 1·7 × 10-3 ). We conclude that our novel metric - ERM-D8 - based on time-series GEP after 8 days of remission-induction therapy can independently predict relapse even after adjusting for NCI risk, genetics, Day 8 peripheral blood response and MRD.

Ryanodine receptor antagonism alleviates skeletal muscle ischemia reperfusion injury by modulating TNF-α and IL-10.

BACKGROUND: Intracellular calcium overload has been implicated in various pathological conditions including ischemia reperfusion injury. This study aims to explore the effect and probable mechanism of dantrolene, a ryanodine receptor and intracellular calcium antagonist, on the skeletal muscle ischemia reperfusion injury. MATERIALS AND METHODS: SD rats were randomly divided into three groups: sham group which underwent anaesthesia and exposure of femoral vein, reperfusion group that received 2 h ischemia and the amount of diluent via femoral vein before 4 h reperfusion, dantrolene group that underwent 2 h ischemia and was given 2 mg/kg dantrolene via femoral vein before 4 h reperfusion. The parameters measured at the end of reperfusion included serum maleic dialdehyde (MDA), tissue myeloperoxidase (MPO) and muscle histology, as well as serum TNF-α and IL-10. RESULTS: Levels of MDA, MPO and TNF-α increased in the reperfusion group, whereas the relevant expressions in the dantrolene group decreased significantly. Histological examination demonstrated significant improvements between the same both groups. IL-10 reflected the protection observed above with a significant up-regulation of expression after dantrolene administration. CONCLUSION: Ryanodine receptor antagonist dantrolene exerted a significant protective effect against the inflammatory injury of skeletal muscle ischemia reperfusion. The underlying molecular mechanism is probably related to the suppression of TNF-α levels and the increment of IL-10 expression.

Pediatric Vaginal Yolk Sac Tumor: Reappraisal of Treatment Strategy in a Rare Tumor at a Unique Location.

Review of the management of 6 young girls with vaginal yolk sac tumor over 25 years showed that the α-fetoprotein levels normalized in 5/6 within 4 cycles of primary cisplatin, bleomycin, etoposide (PEB)/carboplatin, etoposide, bleomycin (JEB)/cisplatin, vinblastine, bleomycin (PVB) chemotherapy. Radioimaging revealed residual tissue but viable tumor was found in only 1 of 2 biopsied. Resection/biopsy is necessary to avoid giving additional primary chemotherapy or to identify patients who need different treatment. If markers do not decay appropriately, PEB/JEB/PVB chemotherapy should not be continued. Taxol-containing salvage chemotherapy regimens, adjuvant modern radiotherapeutic treatment, and fertility-saving curative surgery should then be considered. Despite having mostly advanced disease, 5/6 patients were cured, 2 with chemotherapy alone.

Barrientosiimonas humi gen. nov., sp. nov., an actinobacterium of the family Dermacoccaceae.

Three novel actinobacteria, strains 39(T), 40 and 41, were isolated from soil collected from Barrientos Island in the Antarctic. The taxonomic status of these strains was determined using a polyphasic approach. Comparison of 16S rRNA gene sequences revealed that strain 39(T) represented a novel lineage within the family Dermacoccaceae and was most closely related to members of the genera Demetria (96.9 % 16S rRNA gene sequence similarity), Branchiibius (95.7 %), Dermacoccus (94.4-95.3 %), Calidifontibacter (94.6 %), Luteipulveratus (94.3 %), Yimella (94.2 %) and Kytococcus (93.1 %). Cells were irregular cocci and short rods. The peptidoglycan type was A4α with an L-Lys-L-Ser-D-Asp interpeptide bridge. The cell-wall sugars were galactose and glucose. The major menaquinone was MK-8(H(4)). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphoglycolipid, two glycolipids and one unknown phospholipid. The acyl type of the cell-wall polysaccharide was N-acetyl. The major cellular fatty acids were anteiso-C(17 : 0) (41.97 %), anteiso-C(17 : 1)ω9c (32.16 %) and iso-C(16 : 0) (7.68 %). The DNA G+C content of strain 39(T) was 68.4 mol%. On the basis of phylogenetic and phenotypic differences from other genera of the family Dermacoccaceae, a novel genus and species, Barrientosiimonas humi gen. nov., sp. nov., is proposed; the type strain of the type species is 39(T) (=CGMCC 4.6864(T) = DSM 24617(T)).

Minimal residual disease-guided treatment deintensification for children with acute lymphoblastic leukemia: results from the Malaysia-Singapore acute lymphoblastic leukemia 2003 study.

PURPOSE: To improve treatment outcome for childhood acute lymphoblastic leukemia (ALL), we designed the Malaysia-Singapore ALL 2003 study with treatment stratification based on presenting clinical and genetic features and minimal residual disease (MRD) levels measured by polymerase chain reaction targeting a single antigen-receptor gene rearrangement. PATIENTS AND METHODS: Five hundred fifty-six patients received risk-adapted therapy with a modified Berlin-Frankfurt-Münster-ALL treatment. High-risk ALL was defined by MRD ≥ 1 × 10(-3) at week 12 and/or poor prednisolone response, BCR-ABL1, MLL gene rearrangements, hypodiploid less than 45 chromosomes, or induction failure; standard-risk ALL was defined by MRD ≤ 1 × 10(-4) at weeks 5 and 12 and no extramedullary involvement or high-risk features. Intermediate-risk ALL included all remaining patients. RESULTS: Patients who lacked high-risk presenting features (85.7%) received remission induction therapy with dexamethasone, vincristine, and asparaginase, without anthracyclines. Six-year event-free survival (EFS) was 80.6% ± 3.5%; overall survival was 88.4% ± 3.1%. Standard-risk patients (n = 172; 31%) received significantly deintensified subsequent therapy without compromising EFS (93.2% ± 4.1%). High-risk patients (n = 101; 18%) had the worst EFS (51.8% ± 10%); EFS was 83.6% ± 4.9% in intermediate-risk patients (n = 283; 51%). CONCLUSION: Our results demonstrate significant progress over previous trials in the region. Three-drug remission-induction therapy combined with MRD-based risk stratification to identify poor responders is an effective strategy for childhood ALL.

[Clinical study on Thread-tooth Arc-track Screw Plate System through expandable channels in the treatment of lumbar instability diseases].

OBJECTIVE: To evaluate the validity and reliability of Thread-tooth Arc-track Screw Plate System (TASPS) in the fixation fusion through expandable channels. METHODS: From August 2007 to August 2010, 108 patients with lumbar instability were treated with surgery, including 61 males and 47 females, ranging in age from 26 to 57 years, with an average of 41 years. All the patients were divided into two groups : minimally invasive fusion group and traditional operation group (54 patients in each group). The patients in the minimally invasive fusion group were treated with self-designed TASPS to conduct the fixation fusion through expandable channels by minimally invasive pedicle screw; and the patients in traditional operation group were treated with traditional interbody fixation fusion by pedicle screw. The data were collected and investigated at the 1st week, 3rd month and 1st year postoperatively. The comparative parameters of two groups contained the total operation time, the implanted time, the total amount of bleeding; the VAS score, ODI score and improvement rate at each investigated period; the intervertebral space height of preoperative and postoperative periods; the inefficiency rate of implantation and the fusion rate of postoperative period. RESULTS: All incisions were healed by first stage without any complications such as dural tear, injury of nerve root or cauda equine, intervertebral space infection. The patients in the minimally invasive fusion group needed longer operative time than that of the traditional operation group, but had less total amount of intraoperative and postoperative bleeding and shorter implanted time of pedicle screw than those of the traditional operation group. The VAS scores of two groups at the 1st week after operation significantly decreased compared with that of the 1st day before the operation, and the difference was of high statistical significance. And the VAS scores of two groups at the 3rd month and 1st year after operation also significantly decreased compared with that of the 1st day before the operation, and the difference was highly statistically significant. By comparing the VAS score and ODI score at the 1st week, 3rd month and 1st year postoperatively, the results showed that the VAS score and ODI score of the minimally invasive fusion group were all lower than those of the traditional operation group, and the differences were of high statistical meaningfulness. After 1 year, the improvement rate of the minimally invasive fusion group was (77.46 +/- 6.34)%, while that of the traditional operation group was (72.73 +/- 4.49)%, and the difference was highly statistically significant (P < 0.01). The intervertebral space heights of two groups remarkably increased. At the 3rd month after operation, the difference of intervertebral space heights of the two groups was of no statistical significance. At the 1st year after operation, intervertebral space heights of the two groups were lost to some extent, but the height of the minimally invasive fusion group was higher than that of the traditional operation group, and the difference was statistically significant. The fusion rates of the two groups after 1 year were 100%. CONCLUSION: The fixation fusion through expandable channels by minimally invasive pedicle screw possesses the characteristics of fewer traumas, less intraoperative blood loss, less postoperative pain and rapid recovery. Since its intervertebral fusion rate is similar to the open surgery, it can be viewed as one effective approach for the treatment of lumbar instability diseases. And TASPS is reasonably designed, easy to install and reliably fixed with good reduction effect, which can be applied through expandable channels.

Analysis of 120 pediatric patients with nonmalignant disorders transplanted using unrelated plasma-depleted or -reduced cord blood.

BACKGROUND: Unrelated cord blood (CB) is an important stem cell source for unrelated hematopoietic cell transplantation (HCT) of patients with nonmalignant disorders. Processing methods to prepare red blood cell-reduced CB units incur significant nucleated cell loss. In contrast, plasma depletion or reduction (PDR) processing of CB units entails the removal of only a portion of the plasma with minimal nucleated cell loss. However, there are relatively limited data regarding outcomes of CB transplants using units processed by PDR. STUDY DESIGN AND METHODS: A Center for International Blood and Marrow Transplant Research (CIBMTR)-audited analysis was performed on 120 pediatric patients with nonmalignant disorders transplanted between November 2001 and January 2008 at 29 US and 17 international centers using PDR CB units from two CB banks. RESULTS: Transplant characteristics were as follows: median age, 3.5 years (range, 0.1-14 years); median patient weight, 15 kg (range, 4-61 kg); 58% male; HLA matches (intermediate-resolution HLA-A and HLA-B and high-resolution HLA-DRB1) of the units used in these patients six of six in 26, five of six in 48, four of six in 47, and three of six or two of six in 6; median prefreeze total nucleated cell dose, 10.5×10(7)/kg; median prefreeze CD34+ dose, 3.7×10(5)/kg; and nonmyeloablative regimen in 24%. The median times to myeloid and platelet engraftment were 21 and 49 days, respectively. The cumulative incidence of reported Grade II to IV acute graft-versus-host disease (aGVHD) was 38±5%, and 19±4% had Grade III to IV aGVHD. The Kaplan-Meier estimates of 3-year transplant-related mortality, overall survival, and disease-free survival were 20±4, 79±4, and 70±6%, respectively. CONCLUSION: These data demonstrate the effectiveness of PDR CB units for HCT.

Streptomyces sanyensis sp. nov., isolated from mangrove sediment.

A novel strain, 219820(T), whose metabolites were found to be active against tumour cells, was isolated and characterized. The isolate belonged to the genus Streptomyces and had white to grey aerial mycelium and long chains of smooth spores in the aerial mycelium. A phylogenetic tree based on 16S rRNA gene sequences showed that strain 219820(T) had highest similarity to members of the genus Streptomyces and was most closely, albeit loosely, associated with Streptomyces crystallinus NBRC 15401(T) (98.624 % similarity), Streptomyces melanogenes NBRC 12890(T) (98.565 %) and Streptomyces noboritoensis NBRC 13065(T) (98.564 %). However, DNA-DNA relatedness and phenotypic data readily distinguished strain 219820(T) from these phylogenetically related type strains. It is evident from the combination of genotypic and phenotypic data that strain 219820(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces sanyensis sp. nov. is proposed; the type strain is 219820(T) ( = CGMCC 4.5626(T)  = DSM 42014(T)).

Actinomycetes for marine drug discovery isolated from mangrove soils and plants in China.

The mangrove ecosystem is a largely unexplored source for actinomycetes with the potential to produce biologically active secondary metabolites. Consequently, we set out to isolate, characterize and screen actinomycetes from soil and plant material collected from eight mangrove sites in China. Over 2,000 actinomycetes were isolated and of these approximately 20%, 5%, and 10% inhibited the growth of Human Colon Tumor 116 cells, Candida albicans and Staphylococcus aureus, respectively, while 3% inhibited protein tyrosine phosphatase 1B (PTP1B), a protein related to diabetes. In addition, nine isolates inhibited aurora kinase A, an anti-cancer related protein, and three inhibited caspase 3, a protein related to neurodegenerative diseases. Representative bioactive isolates were characterized using genotypic and phenotypic procedures and classified to thirteen genera, notably to the genera Micromonospora and Streptomyces. Actinomycetes showing cytotoxic activity were assigned to seven genera whereas only Micromonospora and Streptomyces strains showed anti-PTP1B activity. We conclude that actinomycetes isolated from mangrove habitats are a potentially rich source for the discovery of anti-infection and anti-tumor compounds, and of agents for treating neurodegenerative diseases and diabetes.

[Bioactivity survey of natural microbial consortium from mangrove].

Microbial natural products have been mainly acquired by pure culture. While in nature, different microorganisms in one habitat may work together as a whole to produce special secondary metabolites to adapt to their environments. "Quorum-sensing" is a way that they would use. A microbial consortium is like a multi-cellular individual that different microorganisms interact with each other to fulfill a special function. A marine fungus only produce antibiotics when a bacterium co-cultured (Cueto et al, 2001); and some traditional Chinese fermentation food are produced by mixed culture. These inspired us that directly using natural microbial consortium instead of isolate the individual microorganism may be a worth to risk in search for bioactive products. In this research, One hundred and eighty one samples were collected from three mangrove areas of Hainan, Guangxi and Guangdong, in China, which were fermented directly and evaluated for their anti-bacteria, anti-fungi and anti-cancer cell activities. Fifteen samples with high activities were further studied. Microorganisms were isolated from these 15 high bioactive samples and re-detected for their bioactivity, among which, microorganisms isolated from 5 samples that numbered 1106, 1122, 1116, 1214 and 1305 didn' t show any activity although the un-isolated samples themselves showed high bioactivity. Four strains were isolated from one sample of number 1146. Among these strains, one strain showed the same bioactivity targets as the sample itself , but lower activity of anti-fungi than the sample itself. The other three strains didn't show any bioactivity. Microorganisms isolated from three samples that numbered 1161, 1123 and 1111, changed their initial bioactivity targets. These results suggested that natural microbial consortium culture have the potential to produce bioactive metabolites. It is supposed that some uncultured microorganisms or the community action may be the reason for their activity. This is an initial step on using microbial consortium to produce bioactive metabolites.

Ethnic differences in the frequency of subtypes of childhood acute lymphoblastic leukemia: results of the Malaysia-Singapore Leukemia Study Group.

Childhood acute lymphoblastic leukemia (ALL) is clinically heterogeneous with prognostically and biologically distinct subtypes. Although racial differences in frequency of different types of childhood ALL have been reported, many are confounded by selected or limited population samples. The Malaysia-Singapore (MA-SPORE) Leukemia Study Group provided a unique platform for the study of the frequency of major subgroups of childhood ALL in a large cohort of unselected multiethnic Asian children. Screening for the prognostically important chromosome abnormalities (TEL-AML1, BCR-ABL, E2A-PBX1, and MLL) using multiplex reverse-transcription polymerase chain reaction was performed on 299 consecutive patients with ALL at 3 study centers (236 de novo, 63 at relapse), with the ethnic composition predominantly Chinese (51.8%) and Malay (34.8%). Reverse-transcription polymerase chain reaction was successful in 278 (93%) of cases screened. The commonest fusion transcript was TEL-AML1 (19.1%) followed by BCR-ABL (7.8%), MLL rearrangements (4.2%), and E2A-PBX1 (3.1%). Chinese have a significantly lower frequency of TEL-AML1 (13.3% in de novo patients) compared with Malays (22.2%) and Indians (21.7%) (P=0.04). Malays have a lower frequency of T-ALL (6.2%) compared with the Chinese and Indians (9.8%). Both Malays (7.4%) and Chinese (5.0%) have significantly higher frequency of BCR-ABL compared with the Indian population (P<0.05) despite a similar median age at presentation. Our study suggests that there are indeed significant and important racial differences in the frequency of subtypes of childhood ALL. Comprehensive subgrouping of childhood ALL may reveal interesting population frequency differences of the various subtypes, their risk factors and hopefully, its etiology.

Minimal residual disease (MRD) measurement as a tool to compare the efficacy of chemotherapeutic drug regimens using Escherichia Coli-asparaginase or Erwinia-asparaginase in childhood acute lymphoblastic leukemia (ALL).

BACKGROUND: L-asparaginase is a crucial drug in childhood acute lymphoblastic leukemia (ALL) induction therapy, but much debate remains regarding the optimal formulation and dosage. As minimal residual disease (MRD) can accurately measure extremely low levels of lymphoblasts, it is a sensitive reflection of leukemia cell kill. We utilized MRD to compare the efficacy of Erwinia-asparaginase (Erwinia-asp) and E. coli-asparaginase (E. coli-asp) during induction therapy for childhood ALL. PROCEDURE: Of 116 precursor-B ALL patients, 22 were treated with Erwinia-asp, 90 with E. coli-asp, and 4 were switched from E. coli-asp to Erwinia-asp. MRD levels at the end of induction were analyzed for 90 patients (Erwinia-asp = 16; E. coli-asp = 74). Patients were stratified into MRD > or =10(-2), between 10(-2)-10(-4) and < or =10(-4). Toxicity information during induction was available for 110 patients. RESULTS: MRD was the only significant prognosticator compared to conventional criteria. Patients treated with Erwinia-asp were 6.7 times more likely to have MRD levels > or =10(-2) (P = 0.031), reflecting slower lymphoblast clearance. While non-asparaginase related toxicities were similar in both groups, more E. coli-asp patients experienced severe asparaginase-related toxicity. CONCLUSION: E. coli-asp is superior to Erwinia-asp in childhood ALL induction. Although E. coli-asp is more toxic, this is balanced by better response to therapy. Early response to treatment as measured by MRD is a direct reflection of leukemic cell kill and is a significant prognosticator of eventual outcome, making it a good surrogate marker to evaluate the efficacy of induction drugs in childhood ALL.