Immunophenotypic clustering in paediatric acute myeloid leukaemia.

Acute myeloid leukaemia (AML) is a highly heterogeneous disease, exhibiting diverse subtypes according to the characteristics of tumour cells. The immunophenotype is one of the aspects acquired routinely through flow cytometry in the diagnosis of AML. Here, we characterized the antigen expression in paediatric AML cases across both morphological and molecular genetic subgroups. We discovered a subgroup of patients with unfavourable prognosis that can be immunologically characterized, irrespective of morphological FAB results or genetic aberrations. Cox regression analysis unveiled key antigens influencing the prognosis of AML patients. In terms of underlying genotypes, we observed that the antigenic profiles and outcomes of one specific group, primarily composed of CBFA2T3::GLIS2 and FUS::ERG, were analogous to the reported RAM phenotype. Overall, our data highlight the significance of immunophenotype to tailor treatment for paediatric AML.

Safety and efficacy of co-administration of CD19 and CD22 CAR-T cells in children with B-ALL relapse after CD19 CAR-T therapy.

BACKGROUND: CD19-targeted chimeric antigen receptor T-cell (CAR-T) therapy has shown remarkable efficacy in treating relapsed or refractory pediatric B-lineage acute lymphoblastic leukemia (B-ALL). However, poor results are obtained when the same product is reused in patients who relapse after CAR-T. Therefore, there is a need to explore the safety and efficacy of co-administration of CD19- and CD22-targeted CAR-T as a salvage second CAR-T therapy (CART2) in B-ALL patients who relapse after their first CD19 CAR-T treatment (CART1). METHODS: In this study, we recruited five patients who relapsed after CD19-targeted CAR-T. CD19- and CD22-CAR lentivirus-transfected T cells were cultured separately and mixed before infusion in an approximate ratio of 1:1. The total dose range of CD19 and CD22 CAR-T was 4.3 × 106-1.5 × 107/kg. Throughout the trial, we evaluated the patients' clinical responses, side effects, and the expansion and persistence of CAR-T cells. RESULTS: After CART2, all five patients had minimal residual disease (MRD)-negative complete remission (CR). The 6- and 12-month overall survival (OS) rates were 100%. The median follow-up time was 26.3 months. Three of the five patients bridged to consolidated allogeneic hematopoietic stem cell transplantation (allo-HSCT) after CART2 and remained in MRD-negative CR at the cut-off time. In patient No. 3 (pt03), CAR-T cells were still detected in the peripheral blood (PB) at 347 days post-CART2. Cytokine release syndrome (CRS) only occurred with a grade of ≤ 2, and no patients experienced symptoms of neurologic toxicity during CART2. CONCLUSIONS: Mixed infusion of CD19- and CD22-targeted CAR-T cells is a safe and effective regimen for children with B-ALL who relapse after prior CD19-targeted CAR-T therapy. Salvage CART2 provides an opportunity for bridging to transplantation and long-term survival. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2000032211. Retrospectively registered: April 23, 2020.

Potential Specificity Between Mycorrhizal Fungi Isolated from Widespread Dendrobium spp. and Rare D. huoshanense Seeds.

In nature, orchid seed germination and seedling development depend on compatible mycorrhizal fungi. Mycorrhizal generalist and specificity affect the orchid distribution and rarity. Here, we investigated the specificity toward fungi in the rare D. huoshanense by mycorrhizal fungal isolation and symbiotic germination in vitro. Twenty mycorrhizal fungal strains were isolated from the roots of adult Dendrobium spp. (six and 12 strains from rare D. huoshanense and widespread D. officinale, respectively, and two strains from D. nobile and D. moniliforme, respectively) and 13 strains belong to Tulasnellaceae and seven strains belong to Serendipitaceae. Germination trials in vitro revealed that all 20 tested fungal strains can stimulate seed germination of D. huoshanense, but only nine strains (~ 50%) can support it up to the seedling stage. This finding indicates that generalistic fungi are important for early germination, but only a few can maintain a symbiosis with host in seedling stage. Thus, a shift of the microbial community from seedling to mature stage probably narrows the D. huoshanense distribution range. In addition, to further understand the relationship between the fungal capability to promote seed germination and fungal enzyme activity, we screened the laccase and pectase activity. The results showed that the two enzymes activities of fungi cannot be directly correlated with their germination-promoting activities. Understanding the host specificity degree toward fungi can help to better interpret the limited geographic distribution of D. huoshanense and provides opportunities for in situ and ex situ conservation and reintroduction programs.

Adequate asparaginase is important to prevent central nervous system and testicular relapse of pediatric Philadelphia chromosome-negative B-cell acute lymphoblastic leukemia.

Asparaginase (Asp) is one of the most important drugs for treating acute lymphoblastic leukemia (ALL). However, off-protocol Asp administration (OPAA) or hypersensitivity may disturb its pharmacokinetic profile. In this retrospective study, we sought to determine whether OPAA and hypersensitivity to Escherichia coli asparaginase (E coli Asp) impaired extramedullary relapse prevention in a pediatric ALL cohort treated according to SCMC-ALL-2005 protocol from 2005 to 2014 at the Shanghai Children's Medical Center (SCMC). In total, 676 patients were enrolled in this study, including 369 with OPAA and 60 exhibiting hypersensitivity to E coli Asp. At the end of the most recent follow-up, 58 patients had extramedullary relapse. The 5-year cumulative extramedullary relapse incidence in patients with OPAA was 11.01%, whereas that in patients without OPAA was 5.28% (P = .0036). Moreover, the 5-year cumulative extramedullary relapse incidence in patients that exhibited hypersensitivity to E coli Asp was 16.48%, whereas that in patients without hypersensitivity was 7.59% (P = .0195). Concerning the relapse site, OPAA not only increased central nervous system (CNS) relapse but testicular relapse as well. Based on Fine and Gray multivariate analysis, OPAA and hypersensitivity to Asp were independent risk factors for extramedullary relapse. In conclusion, to prevent extramedullary relapse of ALL, adequate duration to administrate Asp was more important than the total dosage, and more attention should be paid to Asp inadequate due to hypersensitivity.

The efficacy and safety of a homoharringtonine-based protocol for children with acute myeloid leukemia: A retrospective study in China.

The standard chemotherapy for acute myeloid leukemia (AML) is usually composed of anthracyclines and cytarabine. We previously reported that homoharringtonine (HHT) was incorporated into regimens for pediatric AML with acceptable efficacy and tolerable toxicity. We treated newly diagnosed AML patients aged 0-18 years on the AML-SCMC-2009 protocol. A total of 102 de novo newly diagnosed AML patients aged 0-18 years were enrolled. All patients were treated with ten courses of chemotherapy including double induction, high dose cytarabine consolidation, and maintenance. The cumulative dose of HHT was 165 mg/m2 and the daunorubicin dose was 120 mg/m2. Complete remission (CR), overall survival (OS) rate, event free survival (EFS) rate, adverse effect response and prognosis factors were retrospectively evaluated to investigate the long-term outcome and safety of this protocol. Eighty-two patients (80.4%) achieved complete remission with the first induction. The 5-year overall survival and event-free survival rates were 65.0% (SE, 4.9%) and 53.3% (SE, 5.2%), respectively. A first induction failure, age older than 2 years, and BCR-ABL translocation were associated with a significantly worse outcome (p < 0.05). No significant drug-related cardiac toxicity was observed. AML-SCMC-2009 protocol which use HHT as backbone drug is efficacious and tolerated. HHT could partially replace anthracycline to be an effective option for childhood AML.

Genome-wide analysis and prediction of genes involved in the biosynthesis of polysaccharides and bioactive secondary metabolites in high-temperature-tolerant wild Flammulina filiformis.

BACKGROUND: Flammulina filiformis (previously known as Asian F. velutipes) is a popular commercial edible mushroom. Many bioactive compounds with medicinal effects, such as polysaccharides and sesquiterpenoids, have been isolated and identified from F. filiformis, but their biosynthesis and regulation at the molecular level remains unclear. In this study, we sequenced the genome of the wild strain F. filiformis Liu355, predicted its biosynthetic gene clusters (BGCs) and profiled the expression of these genes in wild and cultivar strains and in different developmental stages of the wild F. filiformis strain by a comparative transcriptomic analysis. RESULTS: We found that the genome of the F. filiformis was 35.01 Mb in length and harbored 10,396 gene models. Thirteen putative terpenoid gene clusters were predicted and 12 sesquiterpene synthase genes belonging to four different groups and two type I polyketide synthase gene clusters were identified in the F. filiformis genome. The number of genes related to terpenoid biosynthesis was higher in the wild strain (119 genes) than in the cultivar strain (81 genes). Most terpenoid biosynthesis genes were upregulated in the primordium and fruiting body of the wild strain, while the polyketide synthase genes were generally upregulated in the mycelium of the wild strain. Moreover, genes encoding UDP-glucose pyrophosphorylase and UDP-glucose dehydrogenase, which are involved in polysaccharide biosynthesis, had relatively high transcript levels both in the mycelium and fruiting body of the wild F. filiformis strain. CONCLUSIONS: F. filiformis is enriched in a number of gene clusters involved in the biosynthesis of polysaccharides and terpenoid bioactive compounds and these genes usually display differential expression between wild and cultivar strains, even in different developmental stages. This study expands our knowledge of the biology of F. filiformis and provides valuable data for elucidating the regulation of secondary metabolites in this unique F. filiformis strain.

Symbiotic and Asymbiotic Germination of Dendrobium officinale (Orchidaceae) Respond Differently to Exogenous Gibberellins.

Seeds of almost all orchids depend on mycorrhizal fungi to induce their germination in the wild. The regulation of this symbiotic germination of orchid seeds involves complex crosstalk interactions between mycorrhizal establishment and the germination process. The aim of this study was to investigate the effect of gibberellins (GAs) on the symbiotic germination of Dendrobium officinale seeds and its functioning in the mutualistic interaction between orchid species and their mycobionts. To do this, we used liquid chromatograph-mass spectrometer to quantify endogenous hormones across different development stages between symbiotic and asymbiotic germination of D. officinale, as well as real-time quantitative PCR to investigate gene expression levels during seed germination under the different treatment concentrations of exogenous gibberellic acids (GA3). Our results showed that the level of endogenous GA3 was not significantly different between the asymbiotic and symbiotic germination groups, but the ratio of GA3 and abscisic acids (ABA) was significantly higher during symbiotic germination than asymbiotic germination. Exogenous GA3 treatment showed that a high concentration of GA3 could inhibit fungal colonization in the embryo cell and decrease the seed germination rate, but did not significantly affect asymbiotic germination or the growth of the free-living fungal mycelium. The expression of genes involved in the common symbiotic pathway (e.g., calcium-binding protein and calcium-dependent protein kinase) responded to the changed concentrations of exogenous GA3. Taken together, our results demonstrate that GA3 is probably a key signal molecule for crosstalk between the seed germination pathway and mycorrhiza symbiosis during the orchid seed symbiotic germination.

[Clinical effect of the SCMC APL-2010 regimen in treatment of acute promyelocytic leukemia in children: an analysis of 44 cases].

OBJECTIVE: To study the clinical effect of the SCMC APL-2010 regimen in the treatment of acute promyelocytic leukemia (APL) in children. METHODS: A retrospective analysis was performed for the clinical data of 44 children with APL who received treatment with the SCMC APL-2010 regimen between April 2010 and July 2016. The Kaplan-Meier survival analysis was used to evaluate event-free survival (EFS) rate and overall survival (OS) rate. RESULTS: Of the 44 children with APL, 42 (95%) achieved a complete remission (CR) after one course of treatment and 1 achieved CR after two courses of treatment, with an overall CR rate of 98%. The 9-year EFS and OS rates were 96%±3% and 97.7%±2.2% respectively. As for adverse events, 41 (93%) had infection, 29 (66%) had granulocyte reduction, 12 (27%, 1 died) had differentiation syndrome, 16 (36%) had liver dysfunction, 12 (27%) had adverse gastrointestinal reactions, and 7 (16%) had QT prolongation, 1 (2%) had orchitis, and no secondary neoplasm was observed. CONCLUSIONS: Children with APL receiving the SCMC APL-2010 regimen have a good prognosis and can achieve a long-term survival, while treatment-related infection is commonly seen.

Long-term results of the risk-stratified treatment of childhood acute lymphoblastic leukemia in China.

Long-term follow-up data for childhood acute lymphoblastic leukemia (ALL) are scarce in China because of lacking population-based and hospitalized registry system. This retrospective study, conducted at Shanghai's Children's Medical Center in China (SCMC), aimed to investigate the long-term results of childhood ALL and to identify prognostic factors. The Pediatric Oncology Network Database, designed by St. Jude Children's Research Hospital, USA, were used to collect data for the enrolled patients starting in 2005. From 2005 to 2014, 1085 evaluable patients with ALL aged 1 to 18 years old were enrolled and treated using SCMC-ALL-2005 risk-stratified protocol. Complete remission was achieved in 95.6% of patients. At 5 and 10 years, the event-free survival rate was 68.3 ± 1.4% and 64.6 ± 1.6%, and the overall survival rate was 80.0 ± 1.2% and 76.3 ± 1.6%, respectively. The 5-year event-free survival rates were 81.8 ± 2.0%, 67.0 ± 1.9%, and 14.3 ± 4.0% for patients in low-risk, intermediate-risk, and high-risk groups, respectively. The cumulative risk of relapse was 24.5% at 10 years. Induction failure conferred worse prognosis. Patients younger than 1 year of age at diagnosis, intermediate-risk/high-risk group, male gender, and positive minimal residual disease (MRD) results at day 55, both in the univariate and multivariate analysis, were associated with significantly worse prognosis (P < .05). Patients with positive MRD at both day 35 and day 55 were related to a significantly poor outcome (P < .0001), but not for patients with negitive MRD at day 35. The overall outcomes for ALL patients treated with protocol SCMC-ALL-2005 in SCMC are lower than in developed countries. Factors including age, gender, risk group and MRD results at day 55 were associated with treatment outcomes in childhood ALL.

Relatively favorable prognosis for MLL-rearranged childhood acute leukemia with reciprocal translocations.

BACKGROUND: Mixed-lineage leukemia (MLL) with multifarious partner genes leads to aggressive leukemia with dismal outcomes. METHODS: Using panel-based targeted sequencing, we examined 90 cases with MLL-rearranged (MLL-r) childhood acute leukemia, including 55 with acute lymphoblastic leukemia (ALL) and 35 with acute myeloid leukemia (AML). RESULTS: MLL breakpoints and complete rearrangements were identified. A total of 37.8% (34/90) of patients displayed a single direct MLL fusion gene, 15.6% (14/90) carried a single reciprocal fusion, and 27.8% (25/90) had both reciprocal MLL fusion alleles. The remaining 17 MLL-r cases exhibited complex translocations with homozygous disruptions on chromosome 11 or two breakpoints on the same MLL allele with a deletion of functional regions. A total of 77 patients (45 ALL and 32 AML) received chemotherapy with a median follow-up of 2.5 years. Unexpectedly, we identified children with reciprocal MLL fusions who exhibited relatively favorable outcomes compared with those in children with complex translocations or a single direct MLL fusion allele (66.1% vs. 24.6% and 27.6%, P = 0.001). Reciprocal MLL fusion may be functionally rescued by a partially truncated MLL protein. CONCLUSION: Comprehensive MLL-r analysis by targeted next-generation sequencing can provide detailed molecular information and is helpful for precise stratified treatment and clinical prognosis determination.

[Long-term follow-ups of comprehensive therapies for stage 4 neuroblastoma].

OBJECTIVE: To evaluate the long-term outcomes of childhood stage 4 neuroblastoma (NB) and its correlative prognostic factors. METHODS: Comprehensive protocols including tumor resection, intensive chemotherapy, radiotherapy, autologous bone marrow transplantation and 13-cis-retinoid were designed and implemented. A total of 112 newly diagnosed NB stage 4 patients at Shanghai Children's Medical Center collected from June 1998 to December 2010 were treated. Their clinical features, therapeutic efficacies, long-term outcomes and prognostic factors were analyzed. RESULTS: There were 69 males and 43 females with an age range of 4 months to 15 years. Among them, 12 improving patients didn't complete treatment because of parental decisions. Among those completing the comprehensive protocols, 62 cases (62.0%) achieved very good partial remission (VGPR), 20 (20.0%) achieved partial remission (PR) while another 18 (18.0%) progressed during treatment. The efficiency rate (including VGPR+PR) of treatment was 82.0 % (n = 82). The median follow-up period was 78 (56, 120) months. And 13 cases were lost after a median follow-up of 16 months. The 2, 3, 5-year event-free survival (EFS) was 56.2% (59/105) , 40.8% (40/98) and 21.1% (19/90) respectively. Age (>18 months), poor curative effect (achieving no VGPR at the end of treatment), elevated level of lactate dehydrogenase (LDH) (> 5 times normal value), bone marrow involvement and brain metastasis were poor prognostic factors (χ(2) = 12.01, 13.66, 6.29, 5.44, 16.18, all P < 0.05) . According to the multivariate estimates of hazards, age, high levels of LDH, poor curative effect and brain metastasis were associated with a worse survival (OR = 3.54, 1.89, 3.08, 3.45, all P < 0.05) . Brain metastasis predicted a worse outcome with 100% mortality rate (n = 6). Compared to traditional chemotherapy, topotecan-based chemotherapy could not improved the efficiency (52.6% (10/19) vs 63.2% (36/57) , P > 0.05) and long-term outcome (2 ys-EFS 42.1% (8/19) vs 56.4% (31/55) , P > 0.05). CONCLUSIONS: The prognosis remains poor for neuroblastoma of stage 4. Age (>18 months), poor curative effect (achieving no VGPR at the end of treatment), elevated LDH level (>5 times normal value) and bone marrow infiltration are associated with worse prognosis. Brain metastasis predicts the worst with 100% death rate. Topotecan included chemotherapy can not be proved more effective in this study.

Histiocytic sarcoma following CAR T-cell therapy: a case report.

BACKGROUND: Development of secondary tumor after CART treatment is not well investigated. We report a pediatric B-cell acute lymphoblastic leukemia (B-ALL) patient who developed histiocytic sarcoma shortly after CART therapy. CASE REPORT: A 9-year-old boy diagnosed with relapsed B-ALL presenting the KRAS A146T mutation received autologous mouse-derived CD19 and CD22 chimeric antigen receptor T-cell therapy at our center (Chinese Clinical Trial Registry: ChiCTR2000032211). Thirty days post-CART therapy, the bone marrow showed complete remission. At 85 days post-CART therapy, the boy presented with fever and chills. An abdominal CT scan showed massive hepatomegaly with multiple low-density lesions in the liver. At 130 days post-CART therapy, a bone marrow smear showed abnormal proliferation of macrophages, some of which exhibited phagocytosis. On day 136 post-CART therapy, laparoscopic liver biopsy was performed, revealing multiple yellow-white lesions on the surface of the liver. Microscopically, multifocal lesions were observed, predominantly composed of cells with abundant cytoplasm. Immunohistochemical staining indicated histiocytic origin. Based on the immunohistochemical results, histiocytic sarcoma was diagnosed. The same cytogenetic markers were identified in histiocytic sarcoma. CONCLUSION: Our case illustrates a rare complication after CART therapy. The diagnosis and treatment of histiocytic sarcoma pose many challenges.

[Therapeutic efficacy of allogeneic hematopoietic stem cell transplantation in children with chronic myelogenous leukemia].

OBJECTIVE: To investigate the therapeutic efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children with chronic myelogenous leukemia (CML), and to analyze the possible prognostic factors. METHODS: The clinical data of 20 children with CML who had received allo-HSCT was analyzed retrospectively to investigate possible prognostic factors, including age, sex, interval between diagnosis and transplantation, HLA matching between donors and recipients, illness status on transplantation and acute and chronic graft-versus-host disease (GVHD). RESULTS: At the end of follow-up, 13 of the 20 treated children had disease-free survival (DFS) and the rest (7 cases) died. Four died of severe acute GVHD, two of chronic GVHD and its complications, and one of relapse after transplantation. The three-year DFS was (64.6±1.1%). As shown by the univariate analysis, age was the most important prognostic factor in children with CML who had received allo-HSCT (P<0.05), and in children over 10 years, the prognosis was poor. No other of the above factors had a significant impact on prognosis (P>0.05). The multivariate logistic regression analysis also confirmed age as the only prognostic factor (P<0.01). Severe acute and/or chronic GVHD was the most important cause of patient death. 10/10 HLA-matched donors could improve the transplantation outcome. CONCLUSIONS: Allo-HSCT is an effective treatment for children with CML. To improve the prognosis and treatment outcome, children with CML aged over 10 years should receive allo-HSCT as early as possible. 10/10 HLA-matched donors are preferred in allo-HSCT and GVHD should be prevented.

Association between body mass index at diagnosis and outcomes in Chinese children with newly diagnosed acute lymphoblastic leukemia.

PURPOSE: Studies of the association between body mass index (BMI) at diagnosis and treatment outcome in children with acute lymphoblastic leukemia (ALL) have yielded inconsistent results. Hence, we conducted a retrospective study in a large cohort of Chinese children with ALL treated with contemporary protocols. PATIENTS AND METHODS: A total of 1437 children (62.1% male; median age at diagnosis 5.7 years, range: 2.3-16.3 years) were enrolled in two consecutive clinical trials at the Shanghai Children's Medical Center. The rates of overall survival, event-free survival, relapse, treatment-related mortality, and adverse events were compared among patients who were underweight (BMI < 5th percentile), at a healthy weight (5th to 85th percentile), overweight (>85th to <95th percentile), and obese (≥95th percentile). RESULTS: At diagnosis, 91 (6.3%) patients were underweight, 1070 (74.5%) were at a healthy weight, 91 (6.3%) were overweight, and 185 (12.9%) were obese. No significant association was found between weight status and 5-year overall survival, event-free survival, or relapse in the overall cohort. When analyzed as a continuous variable, a higher BMI Z-score was associated with treatment-related mortality (hazard ratio 1.33 (95% confidence interval [CI], 1.05-1.68%), p = 0.02). The treatment-related mortality rate was higher in the overweight (5.5%, 95% CI 0.8-10.2%) and obese (3.2%, 95% CI 0.6-5.8%) groups compared with the underweight (0.0%) and healthy-weight groups (1.9%, 95% CI 1.1-2.7%; p = 0.04). Multivariable analysis showed that children who were overweight had a higher risk of treatment-related mortality (hazard ratio 3.8, 95% CI 1.3-11.4). CONCLUSION: While body weight status was not associated with event-free survival or overall survival, overweight patients were at higher risk of treatment-related mortality.

Chromatin accessibility landscape of relapsed pediatric B-lineage acute lymphoblastic leukemia.

For around half of the pediatric B-lineage acute lymphoblastic leukemia (B-ALL) patients, the molecular mechanism of relapse remains unclear. To fill this gap in knowledge, here we characterize the chromatin accessibility landscape in pediatric relapsed B-ALL. We observe rewired accessible chromatin regions (ACRs) associated with transcription dysregulation in leukemia cells as compared with normal B-cell progenitors. We show that over a quarter of the ACRs in B-ALL are in quiescent regions with high heterogeneity among B-ALLs. We identify subtype-specific and allele-imbalanced chromatin accessibility by integrating multi-omics data. By characterizing the differential ACRs between diagnosis and relapse in B-ALL, we identify alterations in chromatin accessibility during drug treatment. Further analysis of ACRs associated with relapse free survival leads to the identification of a subgroup of B-ALL which show early relapse. These data provide an advanced and integrative portrait of the importance of chromatin accessibility alterations in tumorigenesis and drug responses.

Coadministration of CD19- and CD22-Directed Chimeric Antigen Receptor T-Cell Therapy in Childhood B-Cell Acute Lymphoblastic Leukemia: A Single-Arm, Multicenter, Phase II Trial.

PURPOSE: We determined the safety and efficacy of coadministration of CD19- and CD22-chimeric antigen receptor (CAR) T cells in patients with refractory disease or high-risk hematologic or isolated extramedullary relapse of B-acute lymphoblastic leukemia. PATIENTS AND METHODS: This phase II trial enrolled 225 evaluable patients age ≤ 20 years between September 17, 2019, and December 31, 2021. We first conducted a safety run-in stage to determine the recommended dose. After interim analysis of the first 30 patients treated (27 at the recommended dose) showing that the treatment was safe and effective, the study enrolled additional patients according to the study design. RESULTS: Complete remission was achieved in 99.0% of the 194 patients with refractory leukemia or hematologic relapse, all negative for minimal residual disease. Their overall 12-month event-free survival (EFS) was 73.5% (95% CI, 67.3 to 80.3). Relapse occurred in 43 patients (24 with CD19+/CD22+ relapse, 16 CD19-/CD22+, one CD19-/CD22-, and two unknown). Consolidative transplantation and persistent B-cell aplasia at 6 months were associated with favorable outcomes. The 12-month EFS was 85.0% (95% CI, 77.2 to 93.6) for the 78 patients treated with transplantation and 69.2% (95% CI, 60.8 to 78.8) for the 116 nontransplanted patients (P = .03, time-dependent covariate Cox model). All 25 patients with persistent B-cell aplasia at 6 months remained in remission at 12 months. The 12-month EFS for the 20 patients with isolated testicular relapse was 95.0% (95% CI, 85.9 to 100), and for the 10 patients with isolated CNS relapse, it was 68.6% (95% CI, 44.5 to 100). Cytokine release syndrome developed in 198 (88.0%) patients, and CAR T-cell neurotoxicity in 47 (20.9%), resulting in three deaths. CONCLUSION: CD19-/CD22-CAR T-cell therapy achieved relatively durable remission in children with relapsed or refractory B-acute lymphoblastic leukemia, including those with isolated or combined extramedullary relapse.[Media: see text].

Comparative Transcriptomics Analysis of the Symbiotic Germination of D. officinale (Orchidaceae) With Emphasis on Plant Cell Wall Modification and Cell Wall-Degrading Enzymes.

Orchid seed germination in nature is an extremely complex physiological and ecological process involving seed development and mutualistic interactions with a restricted range of compatible mycorrhizal fungi. The impact of the fungal species' partner on the orchids' transcriptomic and metabolic response is still unknown. In this study, we performed a comparative transcriptomic analysis between symbiotic and asymbiotic germination at three developmental stages based on two distinct fungi (Tulasnella sp. and Serendipita sp.) inoculated to the same host plant, Dendrobium officinale. Differentially expressed genes (DEGs) encoding important structural proteins of the host plant cell wall were identified, such as epidermis-specific secreted glycoprotein, proline-rich receptor-like protein, and leucine-rich repeat (LRR) extensin-like protein. These DEGs were significantly upregulated in the symbiotic germination stages and especially in the protocorm stage (stage 3) and seedling stage (stage 4). Differentially expressed carbohydrate-active enzymes (CAZymes) in symbiotic fungal mycelium were observed, they represented 66 out of the 266 and 99 out of the 270 CAZymes annotated in Tulasnella sp. and Serendipita sp., respectively. These genes were speculated to be involved in the reduction of plant immune response, successful colonization by fungi, or recognition of mycorrhizal fungi during symbiotic germination of orchid seed. Our study provides important data to further explore the molecular mechanism of symbiotic germination and orchid mycorrhiza and contribute to a better understanding of orchid seed biology.

NUDT15 Genetic Variants in Chinese Han, Uighur, Kirghiz, and Dai Nationalities.

Background: Thiopurines are widely used as anti-cancer and immunosuppressant agents, but have a narrow therapeutic index owing to frequent toxicity and life-threatening bone marrow suppression. The nudix hydrolase 15 (NUDT15) genetic polymorphism is strongly associated with the tolerance and myelosuppressive effect of mercaptopurine administration, but the frequency of NUDT15 variants is known to vary among different ethnic groups or nationalities. At present, the NUDT15 gene polymorphism in ethnic minorities such as the Uighur, Kirghiz, and Dai nationalities in China is unclear. Procedure: DNA samples were isolated from 1,071 Chinese children, including 675 Han children with acute lymphoblastic leukemia and 396 healthy minority children, including 118 Uighur, 126 Kirghiz, and 152 Dai participants. The coding regions of NUDT15 exons 1 to 3 were amplified by polymerase chain reaction. NUDT15 genotypes were identified by Sanger sequencing. Results: Five NUDT15 genetic variants of coding regions including rs746071566 (c.55_56insGAGTCG), rs186364861 (c.52G > A), c.137C > G, and c.138T > G in exon 1, and the variant rs116855232 (c.415C > T) in exon 3 were found among the participants. The frequency of NUDT15 rs746071566 variants was lower in the Uighur and Kirghiz populations than in the Han population and in other East Asian nationalities, while the frequency of c.415C > T variants was lower in the Dai population. The c.52G > A variant was relatively uncommon in children of the Han, Uighur, Kirghiz, and Dai ethnic groups. Notably, the rare variants c.137C > G and c.138T > G in a Uighur child were predicted to be disruptive sites. Conclusion: In summary, our results illustrate the NUDT15 polymorphisms in Chinese children of Han, Uighur, Kirghiz, and Dai nationalities, and provide the most effective detection recommendations for different ethnic groups to predict thiopurine-related toxicity, which could be used to guide future clinical thiopurine dose adjustment.

Distinct genomic landscape of Chinese pediatric acute myeloid leukemia impacts clinical risk classification.

Studies have revealed key genomic aberrations in pediatric acute myeloid leukemia (AML) based on Western populations. It is unknown to what extent the current genomic findings represent populations with different ethnic backgrounds. Here we present the genomic landscape of driver alterations of Chinese pediatric AML and discover previously undescribed genomic aberrations, including the XPO1-TNRC18 fusion. Comprehensively comparing between the Chinese and Western AML cohorts reveal a substantially distinct genomic alteration profile. For example, Chinese AML patients more commonly exhibit mutations in KIT and CSF3R, and less frequently mutated of genes in the RAS signaling pathway. These differences in mutation frequencies lead to the detection of previously uncharacterized co-occurring mutation pairs. Importantly, the distinct driver profile is clinical relevant. We propose a refined prognosis risk classification model which better reflected the adverse event risk for Chinese AML patients. These results emphasize the importance of genetic background in precision medicine.

Outcomes of Anti-CD19 CAR-T Treatment of Pediatric B-ALL with Bone Marrow and Extramedullary Relapse.

PURPOSE: Anti-CD19 chimeric antigen receptor T-cell immunotherapy (19CAR-T) has achieved impressive clinical results in adult and pediatric relapsed/refractory (r/r) B-lineage acute lymphoblastic leukemia (B-ALL). However, the application and effect of CAR-T therapy in B-ALL patients with extramedullary relapse are rarely issued even disqualified in some clinical trials. Here, we examined the efficacy of 19CAR-T in patients with both bone marrow and extramedullary involvement. MATERIALS AND METHODS: CAR-T cells were generated by transfection of primary human T lymphocytes with a lentiviral vector expressing anti-CD19 single chain antibody fragments (scFvs) with the cytoplasmic domains of 4-1BB and CD3ζ, and used to infuse patients diagnosed as having r/r B-ALL with extramedullary origination. Clinical responses were evaluated by the use of bone marrow aspiration, imaging, and flow cytometry. RESULTS: Eight patients received 19CAR-T infusion and all attained complete remission (CR). Only one patient was bridged to hematopoietic stem cell transplantation (HSCT). Although three patients relapsed after infusion, they received 19/22CAR-T infusion sequentially and attained a second remission. To date, five patients are in continuous CR and all eight patients are still alive. The mean follow-up time was 21.9 months, while the 24-month estimated event-free survival is 51.4%. CONCLUSION: 19CAR-T therapy can lead to clinical remission for extramedullary relapsed pediatric B-ALL patients. However, the problem of CD19+ relapses after CAR-T remained to be solved. For patients relapsing after CAR-T, a second CAR-T therapy creates another opportunity for remission for subsequent HSCT.