Epigenetic inactivation of ERF reactivates γ-globin expression in ß-thalassemia.

The fetal-to-adult hemoglobin switch is regulated in a developmental stage-specific manner and reactivation of fetal hemoglobin (HbF) has therapeutic implications for treatment of ß-thalassemia and sickle cell anemia, two major global health problems. Although significant progress has been made in our understanding of the molecular mechanism of the fetal-to-adult hemoglobin switch, the mechanism of epigenetic regulation of HbF silencing remains to be fully defined. Here, we performed whole-genome bisulfite sequencing and RNA sequencing analysis of the bone marrow-derived GYPA+ erythroid cells from ß-thalassemia-affected individuals with widely varying levels of HbF groups (HbF ≥ 95th percentile or HbF ≤ 5th percentile) to screen epigenetic modulators of HbF and phenotypic diversity of ß-thalassemia. We identified an ETS2 repressor factor encoded by ERF, whose promoter hypermethylation and mRNA downregulation are associated with high HbF levels in ß-thalassemia. We further observed that hypermethylation of the ERF promoter mediated by enrichment of DNMT3A leads to demethylation of γ-globin genes and attenuation of binding of ERF on the HBG promoter and eventually re-activation of HbF in ß-thalassemia. We demonstrated that ERF depletion markedly increased HbF production in human CD34+ erythroid progenitor cells, HUDEP-2 cell lines, and transplanted NCG-Kit-V831M mice. ERF represses γ-globin expression by directly binding to two consensus motifs regulating γ-globin gene expression. Importantly, ERF depletion did not affect maturation of erythroid cells. Identification of alterations in DNA methylation of ERF as a modulator of HbF synthesis opens up therapeutic targets for ß-hemoglobinopathies.

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 3 years 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.

Local Treatment of Children Suffering From Parameningeal Rhabdomyosarcoma: A Retrospective Single-Center Study From China.

BACKGROUND: Treatment for parameningeal rhabdomyosarcoma (PM-RMS) has been a challenge since local control is difficult. The goal of this study was to analyse the impact of different local treatment approaches on childhood PM-RMS patients and help dispel the doubt that whether secondary radical surgery (SRS) should be encouraged in the management of PM-RMS. METHODS: A total of 17 children with PM-RMS who received unified systemic chemotherapy and individualized local therapy such as radiotherapy (RT) and/or SRS were included in this retrospective study. The overall survival (OS) and event free survival (EFS) were compared between groups adopting different local strategies. RESULTS: The 3-year OS and EFS of our PM-RMS patients was 75.5% and 56.5% respectively. The OS and EFS of patients who received SRS were both significantly lower than that of the non-SRS group (3-year OS: 50.0% vs 90.0%, P = .031; 3-year EFS: 33.3% vs 60.6%, P = .020). The OS and EFS of the patients who received RT was higher than that of the patients of the non-RT group (3-year OS: 85.6% vs 0%, P = .001; 3-year EFS: 64.0% vs 0%, P = .011). CONCLUSION: This study illustrates that SRS was associated with poor prognosis of PM-RMS and should not be routinely performed. Optimized RT strategies along with more intensive chemotherapy may be alternative options to improve the survival of patients with PM-RMS. Multi-center, large sample and prospective studies are needed to further validate these findings.

Treatment of pediatric refractory or relapsed Epstein-Barr virus-associated hemophagocytic syndrome with PD-1 inhibitors.

PURPOSE: Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) is a type of pediatric HLH that occurs frequently in Asia. Although immunochemotherapy based on etoposide and hormone has improved survival rates, there are still about 30% of HLH patients that do not respond. The objective of the article is to examine the efficacy and safety of programmed cell death protein 1 (PD-1) inhibitors for children with relapsed/refractory (r/r) EBV-HLH. METHODS: A retrospective case note review of four pediatric patients with r/r EBV-HLH who were treated with PD-1 inhibitors at Sun Yat-sen Memorial Hospital, Sun Yat-sen University. RESULTS: All four patients responded to PD-1 inhibitors and achieved partial response after their first infusion. Plasma EBV DNA copy number and HLH-related monitoring indicators decreased in all of these patients. All patients received allogeneic hematopoietic stem cell transplantation (allo-HSCT), and two were still alive at the last follow-up on December 30, 2022. Two patients died because of transplantation-related complications. Serious side effects included increased liver enzymes and edema in two patients. CONCLUSION: PD-1 inhibitors are an effective salvage therapy and can provide a bridge to allo-HSCT for pediatric patients with r/r EBV-HLH. However, side effects should be monitered.

TARGET based m6A methylation-related genes predict prognosis relapsed B-cell acute lymphoblastic leukemia.

PURPOSE: The current study aims to investigate the significance of N6-methyladenosine (m6A) methylationrelated genes in the clinical prognosis of childhood relapsed B-cell acute lymphoblastic leukemia (B-ALLL) patient. METHODS: Transcriptome data and corresponding clinical data on m6A methylation-related genes (including 20 genes) were obtained from the Therapeutically Applicable Research To Generate Effective Treatments (TARGET) database. RESULTS: The bone marrow (BM) samples of 134 newly diagnosed (naive) and 116 relapsed B-ALL from TARGET were enrolled in the current study. Three genes (FTO, HNRNPC, RBM15B) showed significant up-regulation in relapsed B-ALL compared with that in naive B-ALL.The three genes had a significantly worse survival (P < 0.05). The LASSO Cox regression model was used to select the most predictive genes as prognostic indicators, and YTHDC1 and FTO were identified as prognostic factors for relapsed B-ALL. Finally, the results of multivariate regression analysis showed that the risk score of m6A methylation-related genes was an independent prognostic factor in relapsed B-ALL (P < 0.05). CONCLUSION: We found that the expression levels of m6A methylation-related genes were different in naive and relapsed patients with B-ALL and correlated with survival and prognosis.This implies that m6A methylation-related genes may be promising prognostic indicators or therapeutic targets for relapsed B-ALL.

Outcome and prognostic factors of CBF pediatric AML patients with t(8;21) differ from patients with inv(16).

PURPOSE: To explore the outcome and prognostic factors between inv(16) and t(8;21) disrupt core binding factor (CBF) in acute myeloid leukemia (AML). METHODS: The clinical characteristic, probability of achieving complete remission (CR), overall survival (OS) and cumulative incidence of relapse (CIR) were compared between inv(16) and (8;21). RESULTS: The CR rate was 95.2%, 10-year OS was 84.4% and CIR was 29.4%. Subgroup analysis showed that patients with t(8;21) had significant lower 10-year OS and CIR than patients with inv(16). Unexpectedly, there was a trend for pediatric AML receiving five courses cytarabine to have a lower CIR than four courses cytarabine (19.8% vs 29.3%, P = 0.06). Among the cohort of no-gemtuzumab ozogamicin(GO) treatment, inv (16) patients showed a similar 10-year OS (78.9% vs 83.5%; P = 0.69) and an inferior outcome on 10-year CIR (58.6% vs 28.9%, P = 0.01) than those patients with t(8;21). In contrast, inv (16) and t(8;21) patients receiving GO treatment had comparable OS (OS: 90.5% vs. 86.5%, P = 0.66) as well as CIR (40.4% vs. 21.4%, P = 0.13). CONCLUSION: Our data demonstrated that more cumulative cytarabine exposure could improve the outcome of childhood patients with t(8;21), while GO treatment was beneficial to the pediatric patients with inv(16).

ZNF384-Related Fusion Genes in Acute Lymphoblastic Leukemia.

Zinc finger protein 384 (ZNF384) encodes a C2H2-type zinc finger protein that can function as a transcription factor. ZNF384 rearrangement in acute lymphoblastic leukemia (ALL) was first reported in 2002. More than 19 different ZNF384 fusion partners have been detected in ALL. These include E1A-binding protein P300 (EP300), CREB-binding protein (CREBBP), transcription factor 3 (TCF3), TATA-box binding protein associated factor 15 (TAF15), Ewing sarcoma breakpoint region 1 gene (EWSR1), AT-rich interactive domain-containing protein 1B (ARID1B), SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily A, member 4 (SMARCA4), SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily A, member 2 (SMARCA2), synergin gamma (SYNRG), clathrin heavy chain (CLTC), bone morphogenic protein 2-inducible kinase (BMP2K), Nipped-B-like protein (NIPBL), A Kinase Anchoring Protein 8 (AKAP8), Chromosome 11 Open Reading Frame 74 (C11orf74), DEAD-Box Helicase 42 (DDX42), ATP Synthase F1 Subunit Gamma (ATP2C1), Euchromatic Histone Lysine Methyltransferase 1 (EHMT1), Testic Expressed 41 (TEX41), etc. Patients diagnosed with ALL harboring ZNF384 rearrangements commonly had a good prognosis. The mechanisms, performance, and features of different ZNF384 rearrangements in acute lymphoblastic leukemia have been well evaluated.

Vincristine and dexamethasone pulses in addition to maintenance therapy among pediatric acute lymphoblastic leukemia (GD-ALL-2008): An open-label, multicentre, randomized, phase III clinical trial.

The efficacy and safety on the addition of vincristine (VCR) and dexamethasone (DEX) pulses to maintenance therapy among childhood acute lymphoblastic leukemia (ALL) remain uncertain. Herein, we perform an open-label, multicentre, randomized, phase III clinical trial that was conducted at nine major medical centers in Guangdong Province, China. Patients were randomly assigned either the conventional maintenance therapy (control group, n = 384) or the VCR/DEX pulse (treatment group, n = 375). When limited to the SR cohort, 10-year EFS was 82.6% (95% CI: 75.9-89.9) in the control group and 80.7% (95% CI: 74-88.1) in the treatment group (pnon-inferiority  = .0002). Similarly, patients with IR also demonstrated non-inferiority of the treatment group to the control group in terms of 10-year EFS (73.6% [95% CI: 67.6-80] vs. 77.6% [95% CI: 71.8-83.9]; pnon-inferiority  = .005). Among the HR cohort, compared with the control group, patients in the treatment group experienced a significant benefit in terms of 10-year EFS (61.1% [95% CI: 47.7-78.2] vs. 72.6% [95% CI: 55.6-94.7], p = .026) and a trend toward higher 10-year OS (73.8% [95% CI: 61.6-88.4] vs. 87.9% [95% CI: 579.2-97.5], p = .068). In the HR cohort, the total rate of drug-induced liver injury and Grade 3 chemotherapy-induced anemia were both lower for patients in the treatment group than in the control group (55.6% vs. 100%, p = .033; 37.5% vs. 60%, p = .036). Conversely, the total prevalence of chemotherapy-induced thrombocytopenia was higher for patients in the treatment group than in the control group (88.9% vs. 40%, p = .027). Pediatric acute lymphoblastic leukemia with high risk is suitable to VCR/DEX pulse during maintenance phase for the excellent outcome, while the standard-to-intermediate-risk patients could eliminate the pulses.

Metagenomic next-generation sequencing for detection of pathogens in children with hematological diseases complicated with infection.

OBJECTIVE: Infection is one of the most common causes of death in children with hematological diseases. Here, we aim to investigate the value of metagenomic next-generation sequencing (mNGS) in the detection of causative pathogens in children with hematological diseases. METHODS: In this retrospective study, specimens from children with hematological diseases, who were admitted to Sun Yat-Sen University between June 2019 and September 2021, were collected for culture and mNGS. RESULTS: A total of 67 pediatric patients were enrolled, and 96 specimens were collected. The positive rate of mNGS was significantly higher than that of culture (57.2% vs 12.5%, P < 0.01). The concordance (90.9%, 10/11) between the positive results of the two methods was high. mNGS detected more cases with Pneumocystis jeroveci, Aspergillus flavus, viruses, and some rare pathogens than culture. Mixed infections were detected by mNGS in 16 cases. Clinical anti-infective treatment was adjusted according to the results of mNGS, the conditions of most patients improved. CONCLUSION: Compared to culture, mNGS shows great advantages in diagnosing bacterial, fungal, viral, and mixed infections in children with hematologic diseases, positively impacting clinical care. mNGS can be used as a complement to culture for pathogen detection.

Prognostic value and outcome for acute lymphocytic leukemia in children with MLL rearrangement: a case-control study.

PURPOSE: To evaluate the prognostic factors and outcome for acute lymphoblastic leukemia (ALL) in children with MLL rearrangement (MLL-r). METHODS: A total of 124 pediatric patients who were diagnosed with ALL were classified into two groups based on the MLL-r status by using a retrospective case-control study method from June 2008 to June 2020. RESULTS: The prevalence of MLL-r positive in the whole cohort was 4.9%. The complete remission (CR) rate on Day 33 in the MLL-r positive group was not statistically different from the negative group (96.8% vs 97.8%, P = 0.736). Multivariate analysis showed that T-cell, white blood cell counts (WBC) ≥ 50 × 109/L, MLL-AF4, and D15 minimal residual disease (MRD) positive were independent risk factors affecting the prognosis of MLL-r positive children. Stem cell transplantation (SCT) was a favorable independent prognostic factor affecting event-free survival (EFS) in MLL-r positive patients (P = 0.027), and there was a trend toward an independent prognostic effect on overall survival (OS) (P = 0.065). The 10-year predicted EFS for patients with MLL-AF4, MLL-PTD, MLL-ENL, other MLL partner genes, and MLL-r negative cases were 46.67 ± 28.61%, 85.71 ± 22.37%, 75 ± 32.41%, 75 ± 32.41%, and 77.33 ± 10.81%, respectively (P = 0.048). The 10-year predicted OS were 46.67 ± 28.61%, 85.71 ± 22.37%, 75 ± 32.41%, 75 ± 32.41%, and 85.2 ± 9.77%, respectively (P = 0.049). The 124 patients with ALL were followed up and eventually 5 (4%) cases relapsed, with a median relapse time of 3.9 years. CONCLUSION: Patients with MLL-r positive ALL have moderate remission rates, but are prone to relapse with low overall survival. The outcome of MLL-r positive ALL was closely related to the partner genes, and clinical attention should be paid to screening for MLL partner genes and combining them with other prognostic factors for accurate risk stratification.

Impact of posttransplant cyclophosphamide on the outcome of patients undergoing unrelated single-unit umbilical cord blood transplantation for pediatric acute leukemia.

BACKGROUND: Umbilical cord blood transplantation (UCBT) from unrelated donors is one of the successful treatments for acute leukemia in childhood. The most frequent side effect of UCBT is peri-engraftment syndrome (PES), which is directly associated with the greater prevalence of acute and chronic graft-versus-host-disease (aGvHD and cGvHD). In haploidentical stem cell transplantation, posttransplant cyclophosphamide (PTCY) has been demonstrated to be an effective method against GvHD. However, the effects of PTCY as a GvHD prophylactic in UCBT had not been investigated. This study aimed to evaluate the effects of PTCY on the outcomes of UCBT for pediatric acute leukemia. METHODS: This retrospective study included 52 children with acute leukemia who underwent unrelated single-unit UCBT after myeloablative conditioning regimens. The results from the PTCY and non-PTCY groups were compared. RESULTS: The incidence of transplantation-related mortality in non-PTCY and PTCY were 5% and 10% (p = 0.525), respectively. The incidence of relapse in non-PTCY and PTCY were 5% and 23% (p = 0.095), respectively. Second complete remission status (CR2) was an independent risk factor for relapse-free survival (hazard ratio = 9.782, p = 0.001). The odds ratio for sepsis or bacteremia incidence was significantly greater in the PTCY group (9.524, p = 0.017). PTCY group had increased rates of cytomegalovirus activity and fungal infection. The incidence of PES, aGvHD, cGvHD, and hemorrhagic cystitis in the PTCY group was lower than that in the non-PTCY group, although it was not significantly different. Additionally, higher doses of PTCY (29 mg/kg and 40 mg/kg) were associated with lower incidences of aGvHD and severe GvHD (65% and 29%, respectively) than lower doses (93% and 57%, respectively). Engraftment time and graft failure incidence were similar across groups. CONCLUSION: The results support the safety and efficiency of PTCY as part of PES controlling and GvHD prophylaxis in single-unit UCBT for children with acute leukemia. A PTCY dosage of 29 mg/kg to 40 mg/kg appears to be more effective in GvHD prophylaxis for UCBT patients.

CEBPA are independent good prognostic factors in pediatric acute myeloid leukemia.

To evaluate the outcome and prognostic significance of CEBPA mutations among pediatric acute myeloid leukemia (AML) from TARGET dataset. A total of 1803 pediatric patients who were diagnosed with AML were classified into two groups based on the CEBPA status by using a retrospective cohort study method from September 1996 to December 2016. The incidence of CEBPA mutations was 18%. CEBPA mutations were significantly associated with elder age (p < 0.001), higher WBC (p = 0.004), higher proportion of peripheral blood blast (p < 0.001), normal karyotype (p < 0.001), low risk (p < 0.001) and higher complete remission induction rates (p < 0.05). Overall, CEBPA mutations patients had a significantly better 5-year EFS (p < 0.001) and OS (p < 0.001) compared to CEBPA wild-type patients, and this favorable impact was maintained even in the presence of FLT3/ITD mutations. Stem cell transplantation had no significant impact on the survival of patients with coexistence of CEBPA and FLT3/ITD mutations. Multivariate analysis demonstrated that mutated CEBPA were an independent favorable indicators of better outcome in terms of EFS (p = 0.007) and OS (p = 0.039). Our study demonstrate mutated CEBPA have an excellent outcome in pediatric AML patients. Furthermore, pediatric AML patients with coexistence of CEBPA and FLT3/ITD mutation appear to have favorable prognoses and might not required stem cell transplantation.

Indicators of glucose dysregulation and the relationship with iron overload in Chinese children with beta thalassemia major.

INTRODUCTION: Patients with beta thalassemia major (TM) have a higher risk of diabetes and an abnormal oral glucose tolerance test (OGTT), but there is no single agree monitoring parameter that reflects glycemic status. The possible mechanisms include iron overload and blood transfusion, but they require further investigation. PURPOSE: This study explored the role of glycated hemoglobin A1c (HbA1c), fructosamine, and glycated albumin (GA) in evaluating the glucose dysregulation and to determine the potential relationship between iron deposition and glucose metabolism disorder in beta TM. METHODS: A cross-sectional study was performed on 118 patients with beta TM and the control group consisted of 33 healthy children with no statistical differences in age, sex, and body mass index (BMI). Fast plasma glucose (FPG), fast insulin (FINS), insulin resistance index (HOMA-IRI), and insulin sensitivity index (HOMA-ISI) were compared between the patient and control groups. HbA1c, GA, fructosamine, and serum ferritin (SF) were measured in the patient group. OGTT, as well as heart and liver magnetic resonance imaging (MRI) T2*, was performed. For all statistical analyses, SPSS 21.0 was used and p < 0.05 was accepted as statistically significant. RESULTS: FPG, FINS, and HOMA-IRI were significantly increased while HOMA-ISI decreased in the beta TM patients when compared with those in the control group. In patients with beta TM, 17 (14.41%) of patients had been diagnosed with diabetes, while 48 (40.68%) had both impaired fasting glucose and impaired glucose tolerance. HbA1c, GA, and fructosamine were increased according to the degree of abnormal glucose metabolism. Statistically significant differences were found in age, SF, and cardiac T2* between the abnormal and normal OGTT groups. CONCLUSION: HbA1c may be used as a significant measure for monitoring glycemic levels in patients with beta TM. Furthermore, GA and fructosamine were alternative indicators of glucose status. Patients with heart iron deposition or an SF > 4000 µg/L were prone to abnormal glucose metabolism, so chelation therapy should be reinforced.

Pneumocystis jirovecii-associated immune reconstitution inflammatory syndrome-like phenomenon in a child with leukaemia: a case report and literature review.

BACKGROUND: Immune reconstitution inflammatory syndrome (IRIS) refers to the phenomenon of intense immune responses against pathogens in patients with AIDS undergoing antiretroviral therapy to reconstitute immune function, resulting in functional impairment of multiple organs. Non-AIDS immunosuppressed hosts may also develop similar manifestations to IRIS during immune recovery. CASE PRESENTATION: An 8-year-old girl presented with acute lymphoblastic leukaemia was admitted for scheduled chemotherapy treatment. During chemotherapy, she experienced pancytopenia and Pneumocystis jirovecii pneumonia, which was diagnosed based on the abnormal shadows observed on chest computed tomography, the elevation of serum ß-D-glucan, and the positive mNGS results of Pneumocystis jirovecii in both sputum and blood. After treatment with Granulocyte Colony-Stimulating Factor, sulfamethoxazole, and caspofungin, aggravation of lung lesions was discovered and severe interstitial lung disease developed in a short period along with a rapidly increasing leukocyte count. Intravenous methylprednisolone pulse therapy was given, but lung function did not improve, and she finally died after the withdrawal of medical care. CONCLUSIONS: For patients with acute lymphocytic leukaemia infected with Pneumocystis jirovecii, the rapid aggravation of pulmonary lesions in the process of blood recovery and immune reconstitution should raise vigilance against the possibility of IRIS-like reactions. The use of granulocyte stimulating factors may aggravate the inflammatory response in the lungs. The timing, dosage, and duration of treatment of glucocorticoids and the impact of high-dose methylprednisolone pulse therapy on the prognosis of patients should be explored in further research.

Extracellular HMGB1 interacts with RAGE and promotes chemoresistance in acute leukemia cells.

BACKGROUND: Nowadays, acute leukemia (AL) among children has favorable outcome, yet some of them get refractory or relapse mainly due to drug resistance. High-mobility group box 1 (HMGB1) has been proven to have a important role in drug resistance via upregulation of autophagy after chemotherapy treatment in acute leukemia. However, the mechanism how extracellular HMGB1 acts on AL cells and leads to chemoresistance remains elusive. METHOD: CCK8 was used to examine the toxicity of chemotherapeutic drug. Elisa was performed to detect the release of HMGB1. Western blot and mRFP-GFP-LC3 adenoviral particles as well as transmission electron microscopy were used to detect the autophagy flux. Western blot and flow cytometry were applied to evaluate the apoptosis. qPCR and western blot were conducted to detect the expression of drug efflux protein. Lentivirus infection was applied to knock down RAGE. In addition, T-ALL NOD/SCID mice xenograft model was used to observe the effect of inhibiting HMGB1/RAGE axis. RESULTS: We found that extracellular HMGB1 do upregulate autophagy and in the meantime downregulate apoptosis, primarily through interaction with receptor for advanced glycation end products (RAGE). Suppression of RAGE by RNA interference alleviated the level of autophagy and enhanced apoptosis. What's more, HMGB1/RAGE induced autophagy was associated with the activation of ERK1/2 and decreased phosphorylation of mammalian target of rapamycin (mTOR), while HMGB1/RAGE limited apoptosis in a Bcl-2-regulated way mediated by P53. On the other hand, we found that HMGB1/RAGE activated the NF-κB pathway and promoted the expression of P-glycation protein (P-gp) as well as multidrug resistance-associated protein (MRP), both are ATP-binding cassette transporters. In vivo experiment, we found that blocking HMGB1/RAGE axis do have a mild pathological condition and a better survival in T-ALL mice. CONCLUSION: HMGB1/RAGE have a important role in drug resistance after chemotherapy treatment, mainly by regulating autophagy and apoptosis as well as promoting the expression of drug efflux protein such as P-gp and MRP. HMGB1/RAGE might be a promising target to cure AL, especially for those met with relapse and refractory.

DNA index as prognostic factor in childhood acute lymphoblastic leukemia in the COG-TARGET database.

BACKGROUND: This study was aimed to evaluate the value of DNA index(DI) among pediatric acute lymphoblastic leukemia (ALL) treated on Children's Oncology Group (COG) protocols between 2000 and 2015. METHODS: Retrospective study were analysis among pediatric ALL patients from the TARGET dataset. RESULT: Totally, 1668 eligible pediatric patients were enrolled in this study. Of them, 993 are male and 675 are female with a median age of 7.6 years old. The median follow-up for those patients was 7.7 years (range 0.1-15.7 years). The probability of 15-year EFS and OS were reported to be 67.5 ± 3.1% and 78.3 ± 2.5%, respectively. BCR/ABL1 fusion gene affected the early treatment response and the survival of childhood ALL. Moreover, those patients with ETV6/RUNX1 fusion gene were also significantly associated with better EFS (HR = 0.6, 95% CI 0.4-0.8, P = 0.003) and OS (HR = 0.3, 95%CI 0.2-0.5, P < 0.001) compared to patients with no ETV6/RUNX1. On the contrary, BM NR on Day+ 29 showed a significant decrease in EFS (HR = 3.1, 95%CI 2.1-4.5, P < 0.001) and OS (HR = 1.7, 95%CI 1.1-2.8, P = 0.026). Multivariate analysis showed that DI was significantly associated with better EFS and OS. The threshold effect of DI on poor outcome was significant after adjusting for potential confounders. The adjusted regression coefficient (Log RR) was 0.7 (95%CI 0.1-3.2, P = 0.597) for DI < 1.1 while 8.8 (95%CI 1.4-56.0, P = 0.021) for DI ≥ 1.2 and 0.0 (95%CI 0.0-0.8, P = 0.041) for 1.1 ≤ DI < 1.2. Generalized additive models revealed that the lowest rates of the adverse outcomes estimated to occur among DI between 1.1 and 1.2. CONCLUSION: For those childhood ALL treated on COG protocols between 2000 and 2015, ETV6/RUNX1 and BM NR were closely related to the prognosis. Moreover, the DI between 1.1 and 1.2 can serve as a significant cut-point discriminating the risk group, which indicated a favourable prognostic factor.

Reduced intensity of early intensification does not increase the risk of relapse in children with standard risk acute lymphoblastic leukemia - a multi-centric clinical study of GD-2008-ALL protocol.

BACKGROUND: The prognosis of childhood acute lymphoblastic leukemia (ALL) is optimistic with a 5-year event-free survival (EFS) rate of 70-85%. However, the major causes of mortality are chemotherapy toxicity, infection and relapse. The Guangdong (GD)-2008-ALL collaborative protocol was carried out to study the effect of reduced intensity on treatment related mortality (TRM) based on Berlin-Frankfurt-Münster (BFM) 2002 backbone treatment. The study was designed to elucidate whether the reduced intensity is effective and safe for children with ALL. METHODS: The clinical data were obtained from February 28, 2008 to June 30, 2016. A total of 1765 childhood ALL cases from 9 medical centers were collected and data were retrospectively analyzed. Patients were stratified into 3 groups according to bone marrow morphology, prednisone response, age, genotype, and karyotype information: standard risk (SR), intermediate risk (IR) and high risk (HR). For SR group, daunorubicin was decreased in induction IA while duration was reduced in Induction Ib (2 weeks in place of 4 weeks). Doses for CAM were same in all risk groups - SR patients received one CAM, others got two CAMs. RESULTS: The 5-year and 8-year overall survival (OS), event-free survival (EFS) and cumulative incidence of relapse (CIR) were 83.5±0.9% and 83.1±1.0%, 71.9±1.1% and 70.9±1.2%, and 19.5±1.0% and 20.5±1.1%, respectively. The 2-year treatment-related mortality (TRM) was 5.2±0.5%. The 5-year and 8-year OS were 90.7±1.4% and 89.6±1.6% in the SR group, while the 5-year and 8-year EFS were 81.5±1.8% and 80.0±2.0%. In the SR group, 74 (15.2%) patients measured minimal residual disease (MRD) on Day 15 and Day 33 of induction therapy. Among them, 7 patients (9.46%) were MRD positive (≥ 0.01%) on Day 33. The incidence of relapse in the MRD Day 33 positive group (n=7) was 28.6%, while in the MRD Day 33 negative group (n=67) was 7.5% (p=0.129). CONCLUSIONS: The results of GD-2008-ALL protocol are outstanding for reducing TRM in childhood ALL in China with excellent long term EFS. This protocol provided the evidence for further reducing intensity of induction therapy in the SR group according to the risk stratification. MRD levels on Day 15 and Day 33 are appropriate indexes for stratification.

Eltrombopag as first-line treatment for thrombocytopenia among paediatric patients after allogeneic haematopoietic stem cell transplantation.

AIMS: The purpose of this study is to examine the safety and efficacy of eltrombopag as first-line treatment for thrombocytopenia among paediatric patients after haematopoietic stem cell transplantation (HSCT). METHODS: Forty-three childhood patients with thrombocytopenia after HSCT who received eltrombopag were retrospectively analysed. RESULT: Eltrombopag was began at the median of 27 days after HSCT and lasted for 24 days. Thirty-five children responded to eltrombopag therapy, and the cumulative platelet recovery rate was 88.9%. The cumulative incidence of platelet recovery was lower (83.9 vs 100%; P = .035) in patients with decreased numbers of megakaryocytes before starting eltrombopag than in those with normal. Factors associated with a significantly elevated response to eltrobopag from univariate analysis were donor type. Results from the multiple regression analysis found that weight (hazard ratio [HR] = 0.7, 95% confidence interval [CI] 0.5-0.9, P = .022), platelet engraftment time (HR = 1.0, 95%CI 1.0-1.0, P = .012) and bone marrow megakaryocytes (HR = 8.0, 95%CI 1.5-43.3, P = .016) before starting eltrombopag were the independent risk factors. Based on Youden's index algorithm in the receiver-operating characteristic curve, the optimal cut-off value of the maintenance dose of eltrombopag in predicting nonresponders was 4 mg/kg. The area under the receiver-operating characteristic curve was 0.923 with sensitivity of 97.8%, specificity of 87.9%, positive predictive value of 72.3%, and negative predictive value of 92%. None of the paediatric patients stopped using eltrombopag due to side effect or intolerability. CONCLUSION: Eltrombopag is effective and safe in paediatric patients with thrombocytopenia after HSCT. The number of megakaryocytes in bone marrow before eltrombopag treatment may serve as a predictor of the response to eltrombopag. We recommend that the maintenance dose of eltrombopag should not exceed 4 mg/kg/d.

A pyruvate kinase deficiency child with novel PK-LR gene mutations was successfully cured by matched unrelated donor peripheral blood stem cell transplantation.

BACKGROUND: Pyruvate kinase deficiency (PKD) is an autosomal recessive disorder caused by a PK-LR gene mutation. Allogeneic hematopoietic cell transplantation (HCT) is an effective cure for PKD. However, the experience of applying HCT in PKD is limited. METHODS: We present a child with novel PK-LR gene mutations who was successfully cured by matched unrelated donor peripheral blood stem cell transplantation (MUD-PBSCT). RESULTS: A 4-year-old, male patient suffered severe hemolytic anemia and jaundice 5 h after birth. Gene sequencing showed that the pyruvate kinase-liver and RBC (PK-LR) gene had a nonsense mutation in exon 5: c.602G>A (p.W201X), and large deletions in exons 3-9. Both of them were novel pathogenic mutations of the PK-LR gene. After transplantation, the hemoglobin level became normal and the nonsense mutation was undetectable. Grade Ⅳ acute graft-versus-host disease (aGVHD) and extensive chronic graft-versus-host disease (cGVHD) occurred in the patient. However, the GVHD was controlled effectively. The patient is alive and has good quality of life 22 months post-transplant, but has mild oral lichen planus-like lesion. CONCLUSION: Gene sequencing contributes to the diagnosis of PKD. HCT is an effective method for curing PKD, but we should explore how to reduce severe GVHD.

Prediction, management, and prognosis of mixed chimerism after hematopoietic stem cell transplantation in transfusion-dependent pediatric thalassemia patients.

BACKGROUND: Early-onset mixed chimerism (MC) with a high proportion of residual host cells is considered a signal of graft rejection in patients undergoing allogenic hematopoietic stem cell transplantation for transfusion-dependent thalassemia. In order to prevent graft rejection and minimize the risk of treatment-related graft-versus-host disease (GVHD), we established a hierarchical management system based on chimerism analysis. METHOD: This retrospective study provides a comprehensive review of the characteristics, interventions, and outcomes of the 38 patients who developed MC after transplantation among the 144 pediatric thalassemia patients between July 2007 and January 2019 at our center. RESULTS: A sibling donor, a blood type-matched donor, conditioning regimens without fludarabine, and transplants containing <10 × 108 total nucleated cells/kg were identified to be associated with the development of MC. Among the 38 patients developing MC, only four patients rejected the grafts. The response rate to donor lymphocyte infusion (DLI, only for patients receiving sibling donor transplantation) and cytokine immunomodulation without DLI was 70.6% and 42.9%, respectively. Patients that developed GVHD after DLI or cytokine therapy had a more significant increase in donor cell chimerism (16%, range 0%-35%) than those without (8.5%, range -21% to 40%, P = .049). However, even when treatment-related GVHD was included, patients with MC had a lower cumulative incidence of total acute GVHD than patients with complete donor chimerism (29.2% vs 48.0%, P = .030). CONCLUSIONS: Interventions based on chimerism analysis were effective in preventing graft rejection and did not increase treatment-related GVHD in thalassemia patients with MC.