Abnormalities in the bone marrow microenvironment and their protective effects on leukemia cells are among the key factors contributing to refractory, drug resistant, and recurrent leukemia. Studies have demonstrated that tumor-associated macrophages (TAMs) are critical inflammatory cells within the tumor microenvironment. Under the influence of mesenchymal stem cells (MSC), TAMs facilitate the growth, proliferation, and migration of various solid tumor cells. However, whether and how the crosstalk between MSC and macrophages influences the development of leukemia remain unclear. Here, we demonstrate that leukemia-derived MSC (L-MSC) significantly increase the proliferation of leukemia cells, thereby exacerbating the tumor burden. Importantly, the pharmacological depletion of macrophages partially abrogated the tumor-promoting activity of L-MSC. Subsequent findings revealed that macrophages induced by L-MSC exhibited similar tumor-promoting activities, which were mediated by the secretion of IL-6 from L-MSC. Collectively, these results elucidate how leukemia cells remodel the function of MSC to induce TAMs formation, thereby promoting the survival of leukemia cells. Taken together, these findings highlight the complex role of MSC in promoting tumor cell growth and orchestrating the bone marrow niche, positioning these cells as potential therapeutic targets in this disease.

Background NPM1-MLF1 -positive acute myeloid leukemia (AML), driven by the rare t(3;5)(q25;q34) translocation, has an extremely low incidence and an undefined prognostic risk. To address this critical knowledge gap, we established the largest multi-source cohort to date to elucidate its clinico-biological landscape and define its precise risk stratification. Methods We conducted a comprehensive analysis of 29 NPM1-MLF1 -positive AML patients and systematically evaluated morphology, immunology, cytogenetics, and molecular (MICM) profiles, alongside transcriptomic features and long-term survival outcomes. Results The cohort (mean age 23.76 years; 55.2% female) was predominantly characterized by the M2 morphological subtype (44.8%). Molecular profiling revealed a high prevalence of FLT3-ITD (21%) and WT1 (10%) mutations. Clinically, allogeneic hematopoietic stem cell transplantation (allo-HSCT) conferred a long-term survival advantage over chemotherapy alone (7-year OS: 72.9% ± 16.5% vs. 36.4% ± 16.18%, P = 0.46). Crucially, allo-HSCT effectively mitigated early relapse, demonstrating a 2-year cumulative incidence of relapse (CIR) of 0%, compared to 79.32% in the chemotherapy-only group ( P = 0.0053). Survival outcomes were comparable between pediatric and adult cohorts ( P = 0.98), whereas secondary AML showed worse short-term survival compared to de novo cases (1-year OS: 0% vs. 54.8%, P = 0.50). Transcriptomically, NPM1-MLF1 -positive AML exhibited a distinct expression profile characterized by the significant upregulation of the HOXA/HOXB gene family compared to healthy controls. While sharing global transcriptomic similarities with NPM1c + AML, it harbored a small cluster of differentially expressed genes, notably MLF1. Conclusion NPM1-MLF1 -positive AML represents a clinically high-risk subtype. Its prognosis is independent of age but depends critically on the chosen treatment modality. Although chemotherapy achieved acceptable induction remission rates, it was associated with poor survival and high relapse rates. In contrast, consolidation with allo-HSCT can significantly improve survival outcomes and reduce the incidence of relapse. FLT3-ITD and WT1 mutations may also correlate with poor prognosis and high relapse. Therefore, bridging to allo-HSCT is essential to overcome the adverse natural history of this disease and achieve long-term survival.

Abstract Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. While genomic studies have identified key molecular subtypes and aberrations in ALL, it requires integrating multi-omics data to complete complex and time-consuming analyses in large retrospective cohorts. It is challenging to perform individualized clinical genomic analysis in real-world. We present a nationwide precision genomic study as part of the Chinese Children Cancer Group ALL 2020 clinical trial. Between 2020 and 2023, 6486 pediatric ALL patients were enrolled from 25 medical centers across 15 provinces in China. RNA-seq was performed for 5103 patients during diagnosis. We developed the National Children's Medical Center ALL Bio-Cloud (NCMC-ABC), an automated, cloud-based framework for real-time RNA-seq data process. NCMC-ABC is designed to analyze multiple clinically relevant genomic aberrations from single RNA-seq data, including molecular subtypes, coding and noncoding driver mutations, fusions and CNVs. The median turnaround time from sample collection to clinical reporting was 14 days across all hospitals, aligning with clinical treatment timelines. We established a molecular subtype classification framework for pediatric ALL, and successfully classified 94.94% of B-ALLs into 20 subtypes and 86.38% of T-ALLs into 11 subtypes. This framework significantly improved the traditional MICM approach, which classified only 48.58% of B-ALLs and did not account for T-ALL subtypes. The enhanced classification is due to the improved detection of key fusions (DUX4, PAX5, ZNF384, MEF2D rearrangements) and mutations (PAX5 P80R and IKZF1 N159Y). Meanwhile, we achieved more precise subtyping of HYPO, HYPER and KMT2A BALLs. The refined subtypes unveiled a distinct profile of Chinese B-ALL patients, with higher frequencies of HYPER, ETV6, DUX4 and PH subtypes, and lower frequencies of Ph-like, iAMP21 and HYPO, compared to Western cohorts. Importantly, the refined framework directly improved the risk stratification of patients. We identified a median of 2.44 pathogenic SNPs/indels and 1.28 fusions per patient. The driver mutations were detected in 259 genes in B-ALL and 156 in T-ALL. We observed different driver mutation profiles in our cohort compared to the Western cohort. Mutations in RAS pathway (NRAS, KRAS and PTPN11) were more frequent in Chinese patients, whereas the JAK-STAT (JAK2, IL7R, SH2B3 and CRLF2) pathway was more frequently mutated in Western cohort. We observed direct clinical relevance of these aberrations. For example, patients with TP53 and NR3C1 mutations showed inferior treatment response. The implementation of NCMC-ABC in a nationwide multicenter pediatric ALL clinical trial demonstrated its effectiveness and feasibility in real-world, improving risk stratification and therapeutic decision making in clinic. Citation Format: Han Wang, Jiaoyang Cai, Jie Yu, Shaoyan Hu, Yongjun Fang, Ju Gao, Jian Li, Hua Jiang, Xiuli Ju, Sixi Liu, Wenyong Kuang, Runming Jin, Liangchun Yang, Xuedong Wu, Xiaowen Zhai, Qun Hu, Hui Jiang, Ningling Wang, Chi Kong Li, Lirong Sun, Jiao Jin, Chun Li, Changda Liang, Yan Dai, Kaili Pan, Hao Xiong, Ching-Hon Pui, Shuhong Shen, Yu Liu. Cloud-based computational framework for individualized genomic analysis in pediatric acute lymphoblastic leukemia: A nationwide multi-center real-world clinical study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 5283.

Treating pediatric acute myeloid leukemia (AML) with NUP98 rearrangement (NUP98-R) is challenging. Standard chemotherapy results in low remission rates. This study aimed to evaluate different induction regimens and explore alternative therapies to improve outcomes. This retrospective study included 111 pediatric patients with AML treated at our institution from March 2012 to March 2023. Patients were classified into two groups: NUP98-R-positive (n = 10) and NUP98-R-negative (n = 101). We compared their clinical characteristics, treatment responses, and prognoses. Additionally, we presented three cases of NUP98-R-positive patients to elaborate on the role of targeted therapies during induction in treatment outcomes and prognosis. Patients with NUP98-R fusion genes had a complete remission (CR) rate of 20

T-cell lymphoblastic lymphoma (T-LBL) is an aggressive lymphoma that primarily affects children and young adults, and a comprehensive understanding of its molecular features is crucial for improving patient outcomes. In this study, 552 patients were included, with targeted next-generation sequencing of 262 lymphoma-associated genes performed on tumour samples from 119 patients. The associations between mutations and survival rates, as well as relapse and other clinical factors, were analysed. The results demonstrated that pleural effusion (PE) invasion was significantly associated with adverse event-free survival (EFS) and overall survival (OS) (p < 0.05). Additionally, we identified 92 genes with recurrent mutations, among which NOTCH1 (44%), FBXW7 (28%), PHF6 (11%), KRAS (10%) and NRAS (10%) were the most frequently altered. Patients with NOTCH1 mutations exhibited improved EFS and OS (p < 0.01), whereas those carrying CREBBP, PTEN and LYST mutations exhibited worse prognosis (p < 0.05). In conclusion, NOTCH1 mutations are associated with a favourable prognosis in paediatric T-LBL, while CREBBP, PTEN and LYST mutations, as well as PE invasion, are linked to poor prognosis. This study identifies key molecular and clinical factors in paediatric T-LBL progression, aiding high-risk patient identification and personalized treatment strategies.

To identify early risk factors for disseminated intravascular coagulation (DIC), particularly severe DIC (grade 4-5), in paediatric acute promyelocytic leukaemia (APL). One hundred and eighty-six paediatric APL patients enrolled in the Chinese Children Leukemia Group (CCLG)-APL 2016 study across 38 hospitals nationwide were grouped based on the occurrence and severity of DIC during induction therapy. DIC occurred in 52.2% of patients during induction therapy, with 7.5% developing grade 4-5 DIC. Significant differences were observed between the DIC and non-DIC groups in the proportion of patients with initial white blood cells (WBC) ≥5 × 109/L, initial platelets (PLT) ≤26 × 109/L and arsenic trioxide (ATO) use (p < 0.05). Multivariate analysis identified initial PLT ≤26 × 109/L (p = 0.002, odds ratio [OR] = 2.679, 95% confidence interval [CI]: 1.438-4.992) as an independent risk factor, while induction therapy using realgar-indigo naturalis formula (RIF) was a protective factor (p = 0.030, OR = 0.465, 95% CI: 0.232-0.929). Further analysis revealed that Fms-like tyrosine kinase 3 (FLT3) mutation (p = 0.023, OR = 11.742, 95% CI: 1.405-98.149), initial PLT ≤26 × 109/L (p = 0.017, OR = 13.784, 95% CI: 1.598-118.905) and initial bone marrow blasts ≥90% (p = 0.030, OR = 5.289, 95% CI: 1.178-23.744) were significant risk factors for grade 4-5 DIC. Initial WBC ≥5 × 109/L and PLT ≤26 × 109/L are associated with an increased risk of DIC, with PLT ≤26 × 109/L as an independent risk factor. Compared with ATO, RIF is a protective factor during induction therapy. Additionally, FLT3 mutation, PLT ≤26 × 109/L and initial bone marrow blasts ≥90% are independent risk factors for grade 4-5 DIC.

China-Net Childhood Lymphoma (CNCL) group B-NHL-2017 study is a prospective multi-center study in China, with the purpose of standardizing the diagnosis and treatment of childhood lymphoma, and improving the prognosis. From May 2017 to June 2023, 20 centers participated in the diffuse large B-cell lymphoma (DLBCL) study. The clinical data were analyzed to summarize the clinical characteristics, treatment response and outcome. The primary endpoint was 5-year event-free survival (EFS). The trial is registered with the Chinese Clinical Trial Registry (ChiCTR1800020067). A total of 138 children and adolescents were enrolled, including 101 males and 37 females. The median age of disease diagnosis was 9.0 years (range: 2.3–15.5 years). The range of follow-up time was 17 d–6.0 years. A total of 12 events occurred in this study, including 7 deaths. of which 4 patients died of disease and chemotherapy comorbidities (severe infection, septic shock, etc.), 1 died of disease progression (enlargement of the primary tumor and tumor metastasis), 1 died of recurrence, and 1 died of severe pneumonia in the third year after completing all chemotherapy courses. Recurrence occurred in 6 (4.3

Non-syndromic tooth agenesis (TA) is a rare developmental disorder that impairs oral function, systemic health, psychological well-being, and quality of life. The Wnt signaling pathway plays a central role in TA pathogenesis, and emerging evidence implicates that the low-density lipoprotein receptor-related protein 6 (LRP6) is involved in autosomal-dominant inheritance of TA. In this study, whole-exome sequencing (WES) of a Chinese family uncovered a novel missense mutation (c.692C>T, p.T231M) in LRP6. Sanger sequencing validated this variant, which was identified as a de novo mutation in the proband. Functional assays using qRT-PCR and immunofluorescent staining demonstrated that this mutation impairs LRP6 protein function and disrupts Wnt signaling. Our findings broaden the mutational spectrum of non-syndromic TA and underscore the critical role of LRP6 in TA.

Ethnopharmacological relevance Chronic immune thrombocytopenia (CITP) seriously affects the patients’ quality of life. In the real world, a traditional Chinese medicine, Huaiqihuang Granule (HQH) shows certain value in ITP treatment.It primarily comprises Huai’er(Trametes robiniophia Murr), Gouqizi(Lycium chinense Mill), Huangjing(Polygonatum sibiricum F. Delaroche). Aim of the study This study aims to investigate the clinical efficacy and safety of HQH in children with CITP. Materials and Methods A multi-centre, randomized, double-blind, placebo- controlled clinical trial was conducted among 216 children with CITP from June 27, 2017 to October 14, 2023, at 13 hospitals in China. Patients were followed up for 96 weeks. Patients with CITP were treated with HQH or with matching placebo in a randomized, double-blind, 24-week treatment period. Patients who received placebo and completed 24 weeks of treatment switched to receive HQH, and patients treated with HQH in the double-blind period continued HQH during the following open-label 24-week treatment. Results HQH was superior to placebo in decreasing the bleeding grade and achieving a platelet response. The total clinical effectiveness rate of HQH group (71.74% in 24-week) was higher than that of the placebo group (45.65% in 24-week, p=0.0013). The result was similarly seen when the data of patients with rescue treatment was analyzed as ineffectiveness or excluded. AEs and serious AE was comparable between the two groups. The severe AEs included thrombocytopenia (6.9%), respiratory tract infection (5.1%) and hemorrhagic episodes (2.8%). Conclusions In CITP children, HQH can improve the clinical effectiveness especially the degree of bleeding, and shows good safety even with long-term treatment.

Abstract Background NUP98-rearranged AML has a dismal prognosis with a 2-year OS of less than 35% with current therapies. The combination of hypomethylating agents and BCL-2 inhibitors venetoclax shows promise in some AML patients, and CDK6 inhibitor palbociclib has demonstrated potential anti-leukemia activity in preclinical models. Thus, a multi-center, phase 2 cohort study was conducted to evaluate the efficacy and safety of this combination therapy (palbociclib, venetoclax and azacitidine, VAP) in these patients. Methods This multi-center, single-arm, phase 2 cohort study was conducted across 34 hospitals of China. Eligible patients were aged 0 to 18 years with newly diagnosed NUP98- rearranged AML after induction chemotherapy, or those with refractory or relapsed AML with NUP98 fusions. Patients received azacitidine 75mg/m2 via subcutaneous injection on day 1-7, palbociclib 50mg/m2 via oral administration on day 8-28, and venetoclax 50mg/m2 on day 1, 100mg/m2 on day 2, and 200mg/m2 on day 3-28 via oral administration (VAP regimen). The primary endpoint was the composite of complete remission (CR) and complete remission with incomplete hematologic recovery (CRi), as defined by the International Working Group (IWG) criteria. The secondary endpoints included the overall response rate, minimal residual disease (MRD) status, relapse rate, 2-year overall survival (OS), 2-year event-free survival (EFS), duration of response, and safety. The trial is registered with the Chinese Clinical Trial Registry (ChiCTR2300074396) and conducted in accordance with Good Clinical Practice guidelines. Findings From December 2022 to March 2024, nine patients were enrolled, including six (66.7%) patients with NUP98-NSD1 fusions, two (22.2%) patients with NUP98-KDM5A fusions, and one (11.1%) patient with NUP98-TOP1 fusion. Six patients achieved CR with MRD negativity. All patients with NUP98-NSD1 fusions demonstrated complete molecular remission eventually, while those with NUP98-KDM5A or NUP98-TOP1 fusions had persistent positivity. The median OS and EFS were 21 months and 13 months, respectively. The 2-year OS and EFS rates were 88.9% and 77.8%. Treatment-related adverse events were uncommon, including cytopenia, febrile neutropenia, tumor lysis syndrome and pneumonia. No treatment-related deaths were reported. Conclusion The combination of palbociclib, venetoclax and azacitidine is a safe and effective treatment for pediatric patients with NUP98-rearranged AML. It achieved high rates of durable remission at morphological, immunophenotypic, and molecular levels, offering promising long-term survival outcomes. This regimen could become a new standard of care for this high-risk subgroup, potentially redefining frontline therapy, although larger studies with longer follow-up are needed to confirm these findings.

BACKGROUND:Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne pathogen that causes severe hemorrhagic fever in humans, but no FDA-approved specific antivirals or vaccines are available to treat or prevent SFTS. METHODS:The plasmids construction and transfection were performed to generate the recombinant SFTSV harboring the nanoluciferase gene (SFTSV-Nluc). Immunostaining plaque assay was performed to measure viral titers, and DNA electrophoresis and Sanger sequencing were performed to evaluate the genetic stability. Luciferase assay and quantitative RT-PCR were performed to evaluate the efficacy of antivirals in vitro. Bioluminescence imaging, titration of virus from excised organs, hematology, and histopathology and immunohistochemistry were performed to evaluate the efficacy of antivirals in vivo. FINDINGS:SFTSV-Nluc exhibited high genetic stability and replication kinetics similar to those of wild-type virus (SFTSVwt), then a rapid high-throughput screening system for identifying inhibitors to treat SFTS was developed, and a nucleoside analog, 4-FlU, was identified to effectively inhibit SFTSV in vitro. SFTSV-Nluc mimicked the replication characteristics and localization of SFTSVwt in counterpart model mice. Bioluminescence imaging of SFTSV-Nluc allowed real-time visualization and quantification of SFTSV replication in the mice. 4-FlU was demonstrated to inhibit the replication of SFTSV with more efficiency than T-705 and without obvious adverse effect in vivo. INTERPRETATION:The high-throughput screening system based on SFTSV-Nluc for use in vitro and in vivo revealed that a safe and effective antiviral nucleoside analog, 4-FlU, may be a basis for the strategic treatment of SFTSV and other bunyavirus infections, paving the way for the discovery of antivirals. FUNDING:This work was supported by grants from the National Key Research and Development Plan of China (2021YFC2300700 to L. Zhang, 2022YFC2303300 to L. Zhang), Strategic Priority Research Program of Chinese Academy of Sciences (XDB0490000 to L. Zhang), National Natural Science Foundation of China (31970165 to L. Zhang, U22A20379 to G. Xiao), the Science and Technology Commission of Shanghai Municipality (21S11903100 to Y. Xie), Hubei Natural Science Foundation for Distinguished Young Scholars (2022CFA099 to L. Zhang).

Background: The incidence of testicular relapse in pediatric acute lymphoblastic leukemia (ALL) has been reduced to 2% or lower with the application of modern intensive chemotherapy. However, testes remain the second most common sites for relapsed ALL in children and the management of testicular relapse has not been fully depicted. Herein, we performed a multicenter retrospective study to analyze the clinical features and outcome of pediatric ALL with testicular relapse. Methods: Sixty-seven childhood testicular relapsed ALL patients were enrolled in this study from 13 centers in China. They were all initial treated with the CCCG-ALL-2015 protocol between January 2015 and December 2019. The clinical features, treatment regimens and outcomes of patients were collected. The overall survival (OS) was estimated by the Kaplan-Meier methods and the differences between groups were compared by the log-rank test. Cox proportional-hazards regression model was used for multivariate analysis to evaluate the influencing factors of OS. Results: The median age was 7 years old. The median time from initial diagnosis to testicular relapse was 37 months. Sixty-six patients (99%) were B-ALL. Forty-one patients (61%) were diagnosed as isolated testicular relapse and the remaining 26 patients (39%) were testis combined with bone marrow and/or central nervous system relapse. Eight of 67 patients were abandoned treatment. Fifty-nine patients (88%) accepted treatment with subsequent evaluation. The median follow-up was 33 months and the 4-year OS was 80.1%. Treatment were heterogenous, including chemotherapy alone, irradiation, orchiectomy, CD19-chimeric antigen receptor T (CAR-T) cell therapy and hematopoietic stem cell transplantation (HSCT). The 4-year OS of patients treated with CAR-T cell therapy, orchiectomy and chemotherapy alone were 93.8%, 90.0% and 38.1% (P<0.05), respectively. The 4-year OS of patients accepted HSCT was 77.1%. The 4-year OS of patients with isolated testicular relapse and combined relapse were 87.9% and 68.4% (P=0.064), respectively. Among thirty-seven isolated testicular relapsed children, 19 patients (51%) accepted CD19-CART cell therapy and 10 patients (27%) accepted orchiectomy. The 4-year OS were 92.9% and 100% (P>0.05), respectively. Multivariate analysis identified combined relapse (HR=5.901, 95%CI 1.237-28.158) and chemotherapy alone (HR=6.322, 95%CI 1.393-28.702) were independent prognostic factors for 4-year OS (all P<0.05).Conclusion: Testicular relapse of pediatric ALL mainly occurred 3 years after initial diagnosis. Patients with isolated testicular relapse had a favorable outcome. For isolated testicular relapse, CART cell therapy and orchiectomy were both effective. Orchiectomy would affect fertility, while CART cell therapy is safe and effective and has an advantage in improving life-quality of survivors. For the testicular relapsed patients, chemotherapy alone was less effective, CAR-T cell therapy and/or HSCT are suggested.

Background: B-cell acute lymphoblastic leukemia (B-ALL) is the most common malignant tumor in children. This study aimed to investigate the lymphocyte subsets, their activities and dynamic changes during and after chemotherapy in children wiht B-ALL. Methods: Peripheral blood samples were prospectively and cross-sectional collected from B-ALL children at different treatment time points (50 cases at initial diagnosis, 40 cases after induction, 20 cases at the beginning of maintenance, 15 cases at 61 weeks, the middle of maintenance, 20 cases at the end of treatment, 18 cases at 5-year follow-up) and healthy control children. T, B and NK lymphocyte subsets, immunophenotypes and functions were detected by flow cytometry. Results: Compared with healthy controls, T cells in patients newly diagnosed with B-ALL were in a state of inhibition, senescence and exhaustion. The percentages of CD4+, CD4/CD8, γδ T, CD4+Tnaive as well as CD8+Tnaive were significantly decreased (P < 0.05). The percentages of CD8+, Tregs, CD4+Tcm, CD8+Tem, CD4+PD-1, CD4+TIM-3, CD8+PD-1 and CD8+TIM-3 were significantly increased (P < 0.05). The levels of IFN-γ, IL-4 and IL-2 were significantly lower. NK and NKT cells in B-ALL children were in a state of inhibition, which mainly showed that the percentage of NK and NKT was significantly decreased, and the activator receptor NKP46 and NKG2D were significantly decreased (P < 0.05). After induction therapy, the percentage of B cells decreased significantly (P=0.000), and T cells and NK cells had a partial recovery (P < 0.05). When entering to maintenance therapy, T, B, NK cell percentage and T cell function of patients were the most severely impaired, and then gradually recovered. Till to the end of treatment, the function of lymphocytewas inhibited. At 5 years follow-up, the counts and functions of B and NK cells recovered, but that of T cells did not recover completely. Conclusions: The absolute counts and functions of T cells and NK cells, which were significantly lower in children with B-ALL, gradually recovered after chemotherapy. Detecting the counts and functions of peripheral blood lymphocytes is important for identifying new prognostic markers of ALL, guiding to prevent infection and administering effective immunotherapy.

The efficacy and safety of Huaiqihuang Granules in the treatment of childhood chronic primary immune thrombocytopenia: a multicentre, randomized, double-blind, placebo-controlled clinical study * Correspondence: Fen Zhou, daisy_may@163.com Runming Jin, jinrunm@qq.com Abstract Background: Chronic immune thrombocytopenia (CITP) is a hemorrhagic disease that seriously affects the quality of life of children and their families. Huaiqihuang Granules, a traditional Chinese medicine, has certain value in the treatment of ITP patients in the preliminary clinical findings. To investigate the efficacy and safety of Huaiqihuang Granules in children with CITP, we conducted a multicenter, randomized, double-blind, placebo-controlled study. Methods: Patients with CITP were treated with Huaiqihuang Granules or with matching placebo in a randomized, double-blind, 24-week treatment period. Patients who received placebo and completed 24 weeks of treatment switched to receive Huaiqihuang Granules, and patients treated with Huaiqihuang Granules in the double-blind period continued Huaiqihuang Granules during the following open-label 24-week treatment.The patients were followed up for 96 weeks. Clinical effective (defined as those achieving a platelet count of≥30×109/L and at least twofold more than the basal platelet count, or the degree of bleeding decreased by one or more grade) was evaluated. Results: Huaiqihuang Granules was superior to placebo in achieving a platelet response and in reducing the bleeding risk. The clinical effective rate of Huaiqihuang Granules group (71.74% in 24-week) was higher than that of the Placebo group (45.65% in 24-week, p=0.0013). The most common severe adverse events were respiratory tract infection (7.8%) and immune thrombocytopenic purpura (6.9%) . Conclusions: In CITP children, Huaiqihuang granules can improve the clinical effectiveness especially the degree of bleeding, and shows good safety in long-term treatment. Keywords: Chronic immune thrombocytopenia, Huaiqihuang Granules, efficacy; safety

Introduction: Acute lymphoblastic leukemia (ALL) is one of the most common malignant tumors in children and a leading cause of mortality in children and adolescents. The chimeric antigen receptor (CAR-T) cell therapy has revolutionized the treatment of relapsed/refractory (R/R) B-cell ALL, with the first FDA-approved product, Kymriah (tisagenlecleucel) developed by Novartis, significantly improving remission rates and survival times. pCAR-19B is an autologous CAR-T cell product with an optimized humanized CD19-specific single-chain variable fragment (scFv) designed to address safety concerns. pCAR-19B has been granted “Breakthrough Therapy Designation” by the China National Medical Products Administration for treating B-ALL. This report presents the efficacy and safety outcomes of pCAR-19B in a pivotal clinical trial involving Chinese pediatric and young adult patients with R/R B-cell ALL. Methods: This phase 2 trial (NCT05334823) was a single-arm, open-label, multicenter study. Patients aged ≥ 3 and ≤ 21 years at screening with confirmed CD19+ R/R B-ALL were included. The primary endpoint was the overall remission rate (ORR), defined as complete remission (CR) plus CR with incomplete blood recovery (CRi) within 3 months post-infusion. Results: As of April 18th, 2024, 89 patients had been enrolled and underwent leukapheresis, with 64 patients receiving pCAR-19B infusion. There were no cases of manufacturing failure. Among the infused patients, 6.25%(4/64）were refractory and 93.75%(60/64) had relapsed to multiple lines of prior therapy or allogeneic stem cell transplant. The median age was 11 years (range 3-21), and 56.25% (36/64) were male. Additionally, 75% (48/64) of the patients carried at least one high-risk gene. The median bone marrow (BM) blast burden at baseline was 58.3% (range 5%-98%) with a heavy BM blast burden (≥50%) observed in 56.25% of the patients. At a median follow-up of 211 days (range 35-750), the best ORR was 90.63% (58/64), with 78.13% of patients (50/64) achieving CR and 12.5% of patients (8/64) achieving CRi, surpassing the efficacy of the commercial anti-CD19 CAR-T therapy products reported in R/R B-ALL. 98.27% (57/58) of patients with ORR achieved negative minimal residual disease (MRD)-negative remission. The ORR at 3 months was 76.56% (49/64). The median duration of response (DOR) was 10.61 months (95% confidence interval 7.66-20.96). The median overall survival (OS) was 23.92 months (95% confidence interval 9.86-NR). Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) occurred in 98.44% and 50% of patients, respectively. Grade ≥3 CRS and ICANS were observed in 29.69% and 39.06% of patients, respectively. The median duration of Grade ≥3 CRS and ICANS was 4 days and 3 days, respectively. There were no deaths attributed to CRS or ICANS. Conclusions: Despite a heavy burden of BM blasts and a high risk of genetic variations, pCAR-19B demonstrated high remission rates, achieved a high rate of MRD-negative remission, durable responses, and a tolerable safety profile. This study represents the first pivotal clinical trial of childhood B-ALL in an Asian population, offering a new treatment option for Chinese pediatric and young adult patients with R/R B-ALL.

ObjectiveNeutrophil extracellular traps (NETs) are important factors in initiating and perpetuating inflammation. However, the role of NETs in different subtypes of juvenile idiopathic arthritis (JIA) has been rarely studied. Therefore, we aimed to explore the ability of JIA-derived neutrophils to release NETs and the effect of TNF-α (tumor necrosis factor-alpha) inhibitors on NET formation both in vitro and in vivo, and evaluate the associations of NET-derived products with clinical and immune-related parameters.MethodsThe ability of neutrophils to release NETs and the effect of adalimumab on NET formation was assessed via in vitro stimulation and inhibition studies. Plasma NET-derived products were detected to assess the incidence of NET formation in vivo. Furthermore, flow cytometry and western blotting were used to detect NET-associated signaling components in neutrophils.ResultsCompared to those derived from HCs, neutrophils derived from patients with oligoarticular-JIA, polyarticular-JIA and enthesitis-related arthritis were more prone to generate NETs spontaneously and in response to TNF-α or PMA in vitro. Excessive NET formation existed in peripheral circulation of JIA patients, and elevated plasma levels of NET-derived products (cell-free DNA and MPO-DNA complexes) could accurately distinguish JIA patients from HCs and were positively correlated with disease activity. Multiple linear regression analysis showed that erythrocyte sedimentation rate and TNF-α levels were independent variables and were positively correlated with cell-free DNA concentration. Notably, TNF-α inhibitors could effectively prevent NET formation both in vitro and in vivo. Moreover, the phosphorylation levels of NET-associated kinases in JIA-derived neutrophils were markedly increased.ConclusionOur data suggest that NETs might play pathogenic roles and may be involved in TNF-α-mediated inflammation in JIA. Circulating NET-derived products possess potential diagnostic and disease monitoring value. Furthermore, the preliminary results related to the molecular mechanisms of NET formation in JIA patients provide a theoretical basis for NET-targeted therapy.

As major components of the tumor microenvironment, both mesenchymal stem cells (MSCs) and macrophages can be remodelled and exhibit different phenotypes and functions during tumor initiation and progression. In recent years, increasing evidence has shown that tumor-associated macrophages (TAMs) play a crucial role in the growth, metastasis, and chemotherapy resistance of hematological malignancies, and are associated with poor prognosis. Consequently, TAMs have emerged as promising therapeutic targets. Notably, MSCs exert a profound influence on modulating immune cell functions such as macrophages and granulocytes, thereby playing a crucial role in shaping the immunosuppressive microenvironment surrounding tumors. However, in hematological malignancies, the cellular and molecular mechanisms underlying the interaction between MSCs and macrophages have not been clearly elucidated. In this review, we provide an overview of the role of TAMs in various common hematological malignancies, and discuss the latest advances in understanding the interaction between MSCs and macrophages in disease progression. Additionally, potential therapeutic approaches targeting this relationship are outlined.

Purpose Despite the improved overall survival of childhood B-lineage acute lymphoblastic leukemia (B-ALL) under contemporary risk-directed therapy, ~15% patients still experience relapse which calls for additional prognosis predicting factors. We aim to investigate the impact of sex on clinical outcomes in childhood B-ALL. Patients and Methods Between January 2, 2015, and December 31, 2019, 6916 pediatric patients with newly diagnosed B-ALL were enrolled in the Chinese Children's Cancer Group ALL-2015 clinical trial (CCCG-ALL-2015, ChiCTR-IPR-14005706). Results Among the 6916 cases pediatric B-ALL, the ratio of males to females was 1:0.74 (males 3982, 57.6%; females 2934, 42.4%). An inferior 5-year EFS was observed in males compared with females (79.7%; 95%CI, 78.5-81.0 vs 83.5%; 95%CI, 82.1-84.9; P< .001). Male sex was identified as an independent poor EFS predictor by a multivariant cox model (HR, 1.19; 95%CI, 1.05-1.35; P= .006). Incidence of relapse was the major difference between the two groups. Males had increased relapse risk compared with females, with a 16.4% (95%CI: 15.2-17.6) 5-year cumulative incidence of relapse (females: 12.2%; 95%CI, 11.0-13.4; P< .001) and a 2.9% (95%CI: 2.4-3.5) 5-year cumulative incidence of central nervous system leukemia relapse (females: 1.6%; 95%CI, 1.2-2.2; P< .001). Although the sex impacted the EFS and CIR, males and females achieved a comparable 5-year OS (93.2%; 95%CI, 92.3-94.2 vs 93.2%; 95%CI, 92.4-94.0; P= .800), indicative of the successful salvage therapy for males. Compared with females, males more often had BCR::ABL1 fusion (5.83%, 232/3982 vs 3.31%, 97/2934; P< .001), but no sex-associated difference in the incidence of ETV6::RUNX1, KMT2A-rearranged or TCF3::PBX1 subtypes were noted. Males with BCR::ABL1 fusion or ETV6::RUNX1 fusion exhibited higher relapse rates than females in the same subtype (BCR::ABL1: 38.4%, 89/232 vs 26.8%, 26/97; P= .045; ETV6::RUNX1: 11.9%, 100/838 vs 4.9%, 30/615; P< .001). Such difference was not seen in KMT2A-rearranged or TCF3::PBX1 subtypes. BCR::ABL1 was identified as a male-specific relapse predictor using the multivariate competing risks model. Conclusions Sex impacts the prognosis of childhood B-ALL. Males has an inferior EFS and is identified as a relapse predictor in B-ALL which warrants the development of male-adapted regimen to prevent disease reoccurrence. The mechanism underlying the sex impact needs further investigation.

The outcomes of children with acute lymphoblastic leukemia (ALL) have been incrementally improved with risk-directed chemotherapy but therapy responses remain heterogeneous. Parameters with added prognostic values are warranted to refine the current risk stratification system and inform appropriate therapies. CD9, implicated by our prior single-center study, holds promise as one such parameter. To determine its precise prognostic significance, we analyzed a nationwide, multicenter, uniformly treated cohort of childhood ALL cases, where CD9 status was defined by flow cytometry on diagnostic samples of 3781 subjects. CD9 was expressed in 88.5% of B-ALL and 27.9% of T-ALL cases. It conferred a lower 5-year EFS and a higher CIR in B-ALL but not in T-ALL patients. The prognostic impact of CD9 was most pronounced in the intermediate/high-risk arms and those with minimal residual diseases, particularly at day 19 of remission induction. The adverse impact of CD9 was confined to specific cytogenetics, notably BCR::ABL1 + rather than KMT2A -rearranged leukemia. Multivariate analyses confirmed CD9 as an independent predictor of both events and relapse. The measurement of CD9 offers insights into patients necessitating intervention, warranting its seamless integration into the diagnostic marker panel to inform risk level and timely introduction of therapeutic intervention for childhood ALL.