L-arginine homeostasis governs adult neural stem cell activation by modulating energy metabolism in vivo.

Neurogenesis in the developing and adult brain is intimately linked to remodeling of cellular metabolism. However, it is still unclear how distinct metabolic programs and energy sources govern neural stem cell (NSC) behavior and subsequent neuronal differentiation. Here, we found that adult mice lacking the mitochondrial urea metabolism enzyme, Arginase-II (Arg-II), exhibited NSC overactivation, thereby leading to accelerated NSC pool depletion and decreased hippocampal neurogenesis over time. Mechanistically, Arg-II deficiency resulted in elevated L-arginine levels and induction of a metabolic shift from glycolysis to oxidative phosphorylation (OXPHOS) caused by impaired attachment of hexokinase-I to mitochondria. Notably, selective inhibition of OXPHOS ameliorated NSC overactivation and restored abnormal neurogenesis in Arg-II deficient mice. Therefore, Arg-II-mediated intracellular L-arginine homeostasis directly influences the metabolic fitness of neural stem cells that is essential to maintain neurogenesis with age.

Clonal evolution dissection reveals that a high MSI2 level promotes chemoresistance in T-cell acute lymphoblastic leukemia.

ABSTRACT: T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive cancer with resistant clonal propagation in recurrence. We performed high-throughput droplet-based 5' single-cell RNA with paired T-cell receptor (TCR) sequencing of paired diagnosis-relapse (Dx_Rel) T-ALL samples to dissect the clonal diversities. Two leukemic evolutionary patterns, "clonal shift" and "clonal drift" were unveiled. Targeted single-cell DNA sequencing of paired Dx_Rel T-ALL samples further corroborated the existence of the 2 contrasting clonal evolution patterns, revealing that dynamic transcriptional variation might cause the mutationally static clones to evolve chemotherapy resistance. Analysis of commonly enriched drifted gene signatures showed expression of the RNA-binding protein MSI2 was significantly upregulated in the persistent TCR clonotypes at relapse. Integrated in vitro and in vivo functional studies suggested that MSI2 contributed to the proliferation of T-ALL and promoted chemotherapy resistance through the posttranscriptional regulation of MYC, pinpointing MSI2 as an informative biomarker and novel therapeutic target in T-ALL.

Microtubule-associated protein SlMAP70 interacts with IQ67-domain protein SlIQD21a to regulate fruit shape in tomato.

Tomato (Solanum lycopersicum) fruit shape is related to microtubule organization and the activity of microtubule-associated proteins (MAPs). However, insights into the mechanism of fruit shape formation from a cell biology perspective remain limited. Analysis of the tissue expression profiles of different microtubule regulators revealed that functionally distinct classes of MAPs, including members of the plant-specific MICROTUBULE-ASSOCIATED PROTEIN 70 (MAP70) and IQ67 DOMAIN (IQD, also named SUN in tomato) families, are differentially expressed during fruit development. SlMAP70-1-3 and SlIQD21a are highly expressed during fruit initiation, which relates to the dramatic microtubule pattern rearrangements throughout this developmental stage of tomato fruits. Transgenic tomato lines overexpressing SlMAP70-1 or SlIQD21a produced elongated fruits with reduced cell circularity and microtubule anisotropy, while their loss-of-function mutants showed the opposite phenotype, harboring flatter fruits. Fruits were further elongated in plants coexpressing both SlMAP70-1 and SlIQD21a. We demonstrated that SlMAP70s and SlIQD21a physically interact and that the elongated fruit phenotype is likely due to microtubule stabilization induced by the SlMAP70-SlIQD21a interaction. Together, our results identify SlMAP70 proteins and SlIQD21a as important regulators of fruit elongation and demonstrate that manipulating microtubule function during early fruit development provides an effective approach to alter fruit shape.

mitoSplitter: A mitochondrial variants-based method for efficient demultiplexing of pooled single-cell RNA-seq.

Single-cell RNA-seq (scRNA-seq) analysis of multiple samples separately can be costly and lead to batch effects. Exogenous barcodes or genome-wide RNA mutations can be used to demultiplex pooled scRNA-seq data, but they are experimentally or computationally challenging and limited in scope. Mitochondrial genomes are small but diverse, providing concise genotype information. We developed "mitoSplitter," an algorithm that demultiplexes samples using mitochondrial RNA (mtRNA) variants, and demonstrated that mtRNA variants can be used to demultiplex large-scale scRNA-seq data. Using affordable computational resources, mitoSplitter can accurately analyze 10 samples and 60,000 cells in 6 h. To avoid the batch effects from separated experiments, we applied mitoSplitter to analyze the responses of five non-small cell lung cancer cell lines to BET (Bromodomain and extraterminal) chemical degradation in a multiplexed fashion. We found the synthetic lethality of TOP2A inhibition and BET chemical degradation in BET inhibitor-resistant cells. The result indicates that mitoSplitter can accelerate the application of scRNA-seq assays in biomedical research.

Chimeric mutations in grapevine ENHANCED DISEASE RESISTANCE1 improve resistance to powdery mildew without growth penalty.

Grapevine (Vitis vinifera L.) incurs severe quality degradation and yield loss from powdery mildew, a major fungal disease caused by Erysiphe necator. ENHANCED DISEASE RESISTANCE1 (EDR1), a Raf-like mitogen-activated protein kinase kinase kinase, negatively regulates defense responses against powdery mildew in Arabidopsis (Arabidopsis thaliana). However, little is known about the role of the putatively orthologous EDR1 gene in grapevine. In this study, we obtained grapevine VviEDR1-edited lines using CRISPR/Cas9. Plantlets containing homozygous and bi-allelic indels in VviEDR1 developed leaf lesions shortly after transplanting into the soil and died at the seedling stage. Transgenic plants expressing wild-type VviEDR1 and mutant Vviedr1 alleles as chimera (designated as VviEDR1-chi) developed normally and displayed enhanced resistance to powdery mildew. Interestingly, VviEDR1-chi plants maintained a spatiotemporally distinctive pattern of VviEDR1 mutagenesis: while almost no mutations were detected from terminal buds, ensuring normal function of the apical meristem, mutations occurred in young leaves and increased as leaves matured, resulting in resistance to powdery mildew. Further analysis showed that the resistance observed in VviEDR1-chi plants was associated with callose deposition, increased production of salicylic acid and ethylene, H2O2 production and accumulation, and host cell death. Surprisingly, no growth penalty was observed with VviEDR1-chi plants. Hence, this study demonstrated a role of VviEDR1 in the negative regulation of resistance to powdery mildew in grapevine and provided an avenue for engineering powdery mildew resistance in grapevine.

BL-B01D1, a first-in-class EGFR-HER3 bispecific antibody-drug conjugate, in patients with locally advanced or metastatic solid tumours: a first-in-human, open-label, multicentre, phase 1 study.

BACKGROUND: Antibody-drug conjugates have promising clinical activity in the treatment of solid tumours. BL-B01D1 is a first-in-class EGFR-HER3 bispecific antibody-drug conjugate. We aimed to assess the safety and preliminary antitumour activity of BL-B01D1 in patients with locally advanced or metastatic solid tumours. METHODS: This first-in-human, open-label, multicentre, dose-escalation and dose-expansion phase 1 trial was conducted in seven hospitals in China, enrolling patients aged 18-75 years (dose escalation; phase 1a) or older than 18 years (dose expansion; phase 1b), with a life expectancy of at least 3 months, an Eastern Cooperative Oncology Group performance status of 0-1, and histologically or cytologically confirmed locally advanced or metastatic solid tumours that had progressed on current standard treatment. In the phase 1a i3+3 design, patients received intravenous BL-B01D1 at three different schedules: 0·27 mg/kg, 1·5 mg/kg, and 3·0 mg/kg weekly; 2·5 mg/kg, 3·0 mg/kg, and 3·5 mg/kg on days 1 and 8 of each cycle every 3 weeks; or 5·0 mg/kg and 6·0 mg/kg on day 1 of each cycle every 3 weeks. The primary objectives of phase 1a were to identify the safety, maximum tolerated dose, and dose-limiting toxicity. In phase 1b, patients were treated in two schedules: 2·5 and 3·0 mg/kg on days 1 and 8 every 3 weeks, or 4·5, 5·0, and 6·0 mg/kg on day 1 every 3 weeks. The primary objectives of phase 1b were to assess the safety and recommended phase 2 dose of BL-B01D1, and objective response rate was a key secondary endpoint. Safety was analysed in all patients with safety records who received at least one dose of BL-B01D1. Antitumour activity was assessed in the activity analysis set which included all patients who received at least one dose of BL-B01D1 every 3 weeks. This trial is registered with China Drug Trials, CTR20212923, and ClinicalTrials.gov, NCT05194982, and recruitment is ongoing. FINDINGS: Between Dec 8, 2021, and March 13, 2023, 195 patients (133 [65%] men and 62 [32%] women; 25 in phase 1a and 170 in phase 1b) were consecutively enrolled, including 113 with non-small-cell lung cancer, 42 with nasopharyngeal carcinomas, 13 with small-cell lung cancer, 25 with head and neck squamous cell carcinoma, one with thymic squamous cell carcinoma, and one with submandibular lymphoepithelioma-like carcinoma. In phase 1a, four dose-limiting toxicities were observed (two at 3·0 mg/kg weekly and two at 3·5 mg/kg on days 1 and 8 every 3 weeks; all were febrile neutropenia), thus the maximum tolerated dose was reached at 3·0 mg/kg on days 1 and 8 every 3 weeks and 6·0 mg/kg on day 1 every 3 weeks. Grade 3 or worse treatment-related adverse events occurred in 139 (71%) of 195 patients; the most common of which were neutropenia (91 [47%]), anaemia (76 [39%]), leukopenia (76 [39%]), and thrombocytopenia (63 [32%]). 52 (27%) patients had a dose reduction and five (3%) patients discontinued treatment due to treatment-related adverse events. One patient was reported as having interstitial lung disease. Treatment-related deaths occurred in three (2%) patients (one due to pneumonia, one due to septic shock, and one due to myelosuppression). In 174 patients evaluated for activity, median follow-up was 6·9 months (IQR 4·5-8·9) and 60 (34%; 95% CI 27-42) patients had an objective response. INTERPRETATION: Our results suggest that BL-B01D1 has preliminary antitumour activity in extensively and heavily treated advanced solid tumours with an acceptable safety profile. Based on the safety and antitumour activity data from both phase 1a and 1b, 2·5 mg/kg on days 1 and 8 every 3 weeks was selected as the recommended phase 2 dose in Chinese patients. FUNDING: Sichuan Baili Pharmaceutical. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

DNA methylation patterns in patients with asthenospermia and oligoasthenospermia.

BACKGROUND: Spermatogenesis is a highly regulated and complex process in which DNA methylation plays a crucial role. This study aimed to explore the differential methylation profiles in sperm DNA between patients with asthenospermia (AS) and healthy controls (HCs), those with oligoasthenospermia (OAS) and HCs, and patients with AS and those with OAS. RESULTS: Semen samples and clinical data were collected from five patients with AS, five patients with OAS, and six age-matched HCs. Reduced representation bisulfite sequencing (RRBS) was performed to identify differentially methylated regions (DMRs) in sperm cells among the different types of patients and HCs. A total of 6520, 28,019, and 16,432 DMRs were detected between AS and HC, OAS and HC, and AS and OAS groups, respectively. These DMRs were predominantly located within gene bodies and mapped to 2868, 9296, and 9090 genes in the respective groups. Of note, 12, 9, and 8 DMRs in each group were closely associated with spermatogenesis and male infertility. Furthermore, BDNF, SMARCB1, PIK3CA, and DDX27; RBMX and SPATA17; ASZ1, CDH1, and CHDH were identified as strong differentially methylated candidate genes in each group, respectively. Meanwhile, the GO analysis of DMR-associated genes in the AS vs. HC groups revealed that protein binding, cytoplasm, and transcription (DNA-templated) were the most enriched terms in the biological process (BP), cellular component (CC), and molecular function (MF), respectively. Likewise, in both the OAS vs. HC and AS vs. OAS groups, GO analysis revealed protein binding, nucleus, and transcription (DNA-templated) as the most enriched terms in BP, CC, and MF, respectively. Finally, the KEGG analysis of DMR-annotated genes and these genes at promoters suggested that metabolic pathways were the most significantly associated across all three groups. CONCLUSIONS: The current study results revealed distinctive sperm DNA methylation patterns in the AS vs. HC and OAS vs. HC groups, particularly between patients with AS and those with OAS. The identification of key genes associated with spermatogenesis and male infertility in addition to the differentially enriched metabolic pathways may contribute to uncovering the potential pathogenesis in different types of abnormal sperm parameters.

Phase 2 study of pegylated liposomal doxorubicin plus cyclophosphamide, vincristine/vindesine, and prednisone in newly diagnosed PTCL: 8-year results.

BACKGROUND: Pegylated liposomal doxorubicin (PLD) is a liposome-encapsulated form of doxorubicin with equivalent efficacy and less cardiotoxicity. This phase 2 study evaluated the efficacy and safety of the PLD-containing CHOP regimen in newly diagnosed patients with aggressive peripheral T-cell lymphomas (PTCL). METHODS: Patients received PLD, cyclophosphamide, vincristine/vindesine, plus prednisone every 3 weeks for up to 6 cycles. The primary endpoint was the objective response rate at the end of treatment (EOT). RESULTS: From September 2015 to January 2017, 40 patients were treated. At the EOT, objective response was achieved by 82.5% of patients, with 62.5% complete response. As of the cutoff date (September 26, 2023), median progression-free survival (mPFS) and overall survival (mOS) were not reached (NR). The 2-year, 5-year, and 8-year PFS rates were 55.1%, 52.0%, and 52.0%. OS rate was 80.0% at 2 years, 62.5% at 5 years, and 54.3% at 8 years. Patients with progression of disease within 24 months (POD24) had worse prognosis than those without POD24, regarding mOS (41.2 months vs NR), 5-year OS (33.3% vs 94.4%), and 8-year OS (13.3% vs 94.4%). Common grade 3-4 adverse events were neutropenia (87.5%), leukopenia (80.0%), anemia (17.5%), and pneumonitis (17.5%). CONCLUSION: This combination had long-term benefits and manageable tolerability, particularly with less cardiotoxicity, for aggressive PTCL, which might provide a favorable benefit-risk balance. CLINICALTRIALS.GOV IDENTIFIER: Chinese Clinical Trial Registry, ChiCTR2100054588; IRB Approved: Ethics committee of Fudan University Shanghai Cancer Center (Date 2015.8.31/No. 1508151-13.

Well-Paired-Seq2: High-Throughput and High-Sensitivity Strategy for Characterizing Low RNA-Content Cell/Nucleus Transcriptomes.

Single-cell RNA sequencing (scRNA-seq) is a transformative technology that unravels the intricate cellular state heterogeneity. However, the Poisson-dependent cell capture and low sensitivity in scRNA-seq methods pose challenges for throughput and samples with a low RNA-content. Herein, to address these challenges, we present Well-Paired-Seq2 (WPS2), harnessing size-exclusion and quasi-static hydrodynamics for efficient cell capture. WPS2 exploits molecular crowding effect, tailing activity enhancement in reverse transcription, and homogeneous enzymatic reaction in the initial bead-based amplification to achieve 3116 genes and 8447 transcripts with an average of ∼20000 reads per cell. WPS2 detected 1420 more genes and 4864 more transcripts than our previous Well-Paired-Seq. It sensitively characterizes transcriptomes of low RNA-content single cells and nuclei, overcoming the Poisson limit for cell and barcoded bead capture. WPS2 also profiles transcriptomes from frozen clinical samples, revealing heterogeneous tumor copy number variations and intercellular crosstalk in clear cell renal cell carcinomas. Additionally, we provide the first single-cell-level characterization of rare metanephric adenoma (MA) and uncover potential specific markers. With the advantages of high sensitivity and high throughput, WPS2 holds promise for diverse basic and clinical research.

Outcome of first or second transplantation using unrelated umbilical cord blood without ATG conditioning regimen for pediatric bone marrow failure disorders.

BACKGROUND: Unrelated umbilical cord blood transplantation (UCBT) for bone marrow failure (BMF) disorders using conditioning regimens without Anti-Thymocyte Globulin (ATG) has been used as an alternative transplantation for emerging patients without matched-sibling donors. Experience with this transplant modality in children is limited, especially as a secondary treatment for transplant failure patients. PROCEDURE: We retrospectively reviewed 17 consecutive bone marrow failure patients who underwent unrelated umbilical cord blood transplantation in our center and received conditioning regimens of Total Body Irradiation (TBI) or Busulfan (BU) + Fludarabine (FLU) + Cyclophosphamide (CY). RESULTS: Among the 17 BMF patients, 15 patients were treated with first cord blood transplantation and another 2 with secondary cord blood transplantation because of graft failure after first haploidentical stem cell transplantation at days +38 and +82. All patients engrafted with a median donor cell chimerism of 50 % at days +7 (range, 16 %-99.95 %) and finally rose to 100 % at days +30. Median time to neutrophil engraftment was 19 days (range, 12-30) and time to platelet engraftment was 32 days (range, 18-61). Pre-engraftment syndrome (PES) was found in 16 patients (94.11 %, 16/17). Cumulative incidence of grades II to IV acute GVHD was 58.8 % (95 % CI: 32.7-84.9 %), and 17.6 % (95 % CI: 2.6-37.9 %) of patients developed chronic GVHD. The 3-year overall survival (OS) and failure-free survival (FFS) rates were 92.86 ± 6.88 %. CONCLUSION: UCBT is an effective alternative treatment for bone marrow failure pediatric patients. TBI/BU + FLU + CY regimen ensure a high engraftment rate for unrelated umbilical cord blood transplantation, which overcomes the difficulty of graft failure. Secondary salvage use of cord blood transplantation may still be useful for patients who have failed after other transplantation.

Minimal residual disease monitoring in childhood Philadelphia chromosome-positive acute lymphoblastic leukemia: prognostic significance and correlation between multiparameter flow cytometry and real-time quantitative polymerase chain reaction

Not available.

First-in-human study of GFH018, a small molecule inhibitor of transforming growth factor-ß receptor I inhibitor, in patients with advanced solid tumors.

BACKGROUND: Transforming growth factor-ß (TGF-ß) is a cytokine with multiple functions, including cell growth regulation, extracellular matrix production, angiogenesis homeostasis adjustment and et al. TGF-ß pathway activation promotes tumor metastasis/progression and mediates epithelial-mesenchymal transmission suppressing immunosurveillance in advanced tumors. GFH018, a small molecule inhibitor blocking TGF-ß signal transduction, inhibits the progression and/or metastasis of advanced cancers. This first-in-human study evaluated the safety, tolerability, pharmacokinetics (PK), and efficacy of GFH018 monotherapy in patients with advanced solid tumors. METHODS: This phase I, open-label, multicenter study used a modified 3+3 dose escalation and expansion design. Adult patients with advanced solid tumors failing the standard of care were enrolled. Starting at 5 mg, eight dose levels up to 85 mg were evaluated. Patients received GFH018 BID (14d-on/14d-off) starting on the 4th day after a single dose on cycle 1, day 1. Subsequent cycles were defined as 28 days. The study also explored the safety of 85 mg BID 7d-on/7d-off. Adverse events were graded using NCI criteria for adverse events (NCI-CTCAE v5.0). PK was analyzed using a noncompartmental method. Efficacy was evaluated using RECIST 1.1. Blood samples were collected for biomarker analysis. RESULTS: Fifty patients were enrolled and received at least one dose of GFH018. No dose-limiting toxicity occurred, and the maximum tolerated dose was not reached. Forty-three patients (86.0%) had at least one treatment-related adverse event (TRAE), and three patients (6.0%) had ≥ G3 TRAEs. The most common TRAEs (any grade/grade ≥3) were AST increased (18%/0%), proteinuria (14%/2%), anemia (14%/2%), and ALT increased (12%/0%). No significant cardiotoxicity or bleeding was observed. GFH018 PK was linear and dose-independent, with a mean half-life of 2.25-8.60 h from 5 - 85 mg. Nine patients (18.0%) achieved stable disease, and one patient with thymic carcinoma achieved tumor shrinkage, with the maximum target lesion decreased by 18.4%. Serum TGF-ß1 levels were not associated with clinical responses. The comprehensive recommended dose for Phase II was defined as 85 mg BID 14d-on/14d-off. CONCLUSIONS: GFH018 monotherapy presented a favorable safety profile without cardiac toxicity or bleeding. Modest efficacy warrants further studies, including combination strategies. TRIAL REGISTRATION: ClinicalTrial. gov ( https://www. CLINICALTRIALS: gov/ ), NCT05051241. Registered on 2021-09-02.

Decitabine-containing conditioning improved outcomes for children with higher-risk myelodysplastic syndrome undergoing allogeneic hematopoietic stem cell transplantation.

Myelodysplastic syndrome (MDS) is a rare clonal hematopoietic disorder in children. The risk stratification system and treatment strategy for adults are unfit for children. The role of hypomethylating agents (HMAs) in higher-risk childhood MDS has not been identified. This study aimed to investigate the outcomes of hematopoietic stem cell transplantation (HSCT) in children with higher-risk MDS at one single center. A retrospective study was conducted in children with higher-risk MDS undergoing HSCT between September 2019 and March 2023 at Blood Diseases Hospital CAMS. The clinical characteristics and transplantation information were reviewed and analyzed. A total of 27 patients were analyzed, including 11 with MDS with excess blasts (MDS-EB), 14 with MDS-EB in transformation (MDS-EBt) or acute myeloid leukemia with myelodysplasia-related changes (AML-MRC), and 2 with therapy-related MDS/AML (t-MDS/AML). Eight patients harbored monosomy 7. Before transplantation, induction therapy was administered to 25 patients, and 19 of them achieved bone marrow blasts <5% before HSCT. The stem cell source was unmanipulated-related bone marrow or peripheral blood stem cells for nineteen patients and unrelated cord blood for eight. All patients received decitabine-containing and Bu/Cy-based myeloablative conditioning; 26 patients achieved initial engraftment. The cumulative incidences of grade II-IV and grade III-IV acute graft-versus-host disease (GvHD) at 100 days were 65.4% and 42.3%, respectively. The incidence of cGvHD was 38.5%. The median follow-up was 26 (range 4-49) months after transplantation. By the end of follow-up, two patients died of complications and two died of disease progression. The probability of 3-year overall survival (OS) was 84.8% (95%CI, 71.1 to 98.5%). In summary, decitabine-containing myeloablative conditioning resulted in excellent outcomes for children with higher-risk MDS undergoing allogeneic HSCT.

Combating land degradation through human efforts: Ongoing challenges for sustainable development of global drylands.

Drylands, as highly vulnerable ecosystems, support environmental functions and human well-being. Nevertheless, widespread land degradation and desertification present significant global and regional environmental challenges, with limited consensus on their area and degree. This study used time-series vegetation productivity and meteorological data from 2000 to 2020 to quantify global land degradation trends and driving factors in drylands. The results show a notable restoration of land degradation in drylands worldwide, with the area of improved land exceeding the degraded area by 1.4 times, although the threat of degradation persists. India and China emerge as pioneers in effective land improvement strategies, offering valuable experiences for other regions. Combined effects, as quantitatively distinguished by our established model, dominate the degradation and improvement processes. Notably, human activities play a decisive role in influencing land degradation trends, with the potential for either exacerbation or reversal. This study provides new perspectives on environmental health and human activities from global and regional observations. Finally, our research provides scientific support for desertification control and contributes to the overall advancement of the SDGs globally.

The Metabolite Saccharopine Impairs Neuronal Development by Inhibiting the Neurotrophic Function of Glucose-6-Phosphate Isomerase.

Mutations in the Aminoadipate-Semialdehyde Synthase (AASS) gene encoding α-aminoadipic semialdehyde synthase lead to hyperlysinemia-I, a benign metabolic variant without clinical significance, and hyperlysinemia-II with developmental delay and intellectual disability. Although both forms of hyperlysinemia display biochemical phenotypes of questionable clinical significance, an association between neurologic disorder and a pronounced biochemical abnormality remains a challenging clinical question. Here, we report that Aass mutant male and female mice carrying the R65Q mutation in α-ketoglutarate reductase (LKR) domain have an elevated cerebral lysine level and a normal brain development, whereas the Aass mutant mice carrying the G489E mutation in saccharopine dehydrogenase (SDH) domain exhibit elevations of both cerebral lysine and saccharopine levels and a smaller brain with defective neuronal development. Mechanistically, the accumulated saccharopine, but not lysine, leads to impaired neuronal development by inhibiting the neurotrophic effect of glucose-6-phosphate isomerase (GPI). While extracellular supplementation of GPI restores defective neuronal development caused by G498E mutation in SDH of Aass. Altogether, our findings not only unravel the requirement for saccharopine degradation in neuronal development, but also provide the mechanistic insights for understanding the neurometabolic disorder of hyperlysinemia-II.SIGNIFICANCE STATEMENT The association between neurologic disorder and a pronounced biochemical abnormality in hyperlysinemia remains a challenging clinical question. Here, we report that mice carrying the R65Q mutation in lysine α-ketoglutarate reductase (LKR) domain of aminoadipate-semialdehyde synthase (AASS) have an elevated cerebral lysine levels and a normal brain development, whereas those carrying the G489E mutation in saccharopine dehydrogenase (SDH) domain of AASS exhibit an elevation of both cerebral lysine and saccharopine and a small brain with defective neuronal development. Furthermore, saccharopine impairs neuronal development by inhibiting the neurotrophic effect of glucose-6-phosphate isomerase (GPI). These findings demonstrate saccharopine degradation is essential for neuronal development.

Human antigen R-regulated mRNA metabolism promotes the cell motility of migrating mouse neurons.

Neocortex development during embryonic stages requires the precise control of mRNA metabolism. Human antigen R (HuR) is a well-studied mRNA-binding protein that regulates mRNA metabolism, and it is highly expressed in the neocortex during developmental stages. Deletion of HuR does not impair neural progenitor cell proliferation or differentiation, but it disturbs the laminar structure of the neocortex. We report that HuR is expressed in postmitotic projection neurons during mouse brain development. Specifically, depletion of HuR in these neurons led to a mislocalization of CDP+ neurons in deeper layers of the cortex. Time-lapse microscopy showed that HuR was required for the promotion of cell motility in migrating neurons. PCR array identified profilin 1 (Pfn1) mRNA as a major binding partner of HuR in neurons. HuR positively mediated the stability of Pfn1 mRNA and influenced actin polymerization. Overexpression of Pfn1 successfully rescued the migration defects of HuR-deleted neurons. Our data reveal a post-transcriptional mechanism that maintains actin dynamics during neuronal migration.

The impact of amino acid metabolism on adult neurogenesis.

Adult neurogenesis is a multistage process during which newborn neurons are generated through the activation and proliferation of neural stem cells (NSCs) and integrated into existing neural networks. Impaired adult neurogenesis has been observed in various neurological and psychiatric disorders, suggesting its critical role in cognitive function, brain homeostasis, and neural repair. Over the past decades, mounting evidence has identified a strong association between metabolic status and adult neurogenesis. Here, we aim to summarize how amino acids and their neuroactive metabolites affect adult neurogenesis. Furthermore, we discuss the causal link between amino acid metabolism, adult neurogenesis, and neurological diseases. Finally, we propose that systematic elucidation of how amino acid metabolism regulates adult neurogenesis has profound implications not only for understanding the biological underpinnings of brain development and neurological diseases, but also for providing potential therapeutic strategies to intervene in disease progression.

Single-cell analysis highlights a population of Th17-polarized CD4+ naïve T cells showing IL6/JAK3/STAT3 activation in pediatric severe aplastic anemia.

Acquired aplastic anemia (AA) is recognized as an immune-mediated disorder resulting from active destruction of hematopoietic cells in bone marrow (BM) by effector T lymphocytes. Bulk genomic landscape analysis and transcriptomic profiling have contributed to a better understanding of the recurrent cytogenetic abnormalities and immunologic cues associated with the onset of hematopoietic destruction. However, the functional mechanistic determinants underlying the complexity of heterogeneous T lymphocyte populations as well as their correlation with clinical outcomes remain to be elucidated. To uncover dysfunctional mechanisms acting within the heterogeneous marrow-infiltrating immune environment and examine their pathogenic interplay with the hematopoietic stem/progenitor pool, we exploited single-cell mass cytometry for BM mononuclear cells of severe AA (SAA) patients pre- and post-immunosuppressive therapy, in contrast to those of healthy donors. Alignment of BM cellular composition with hematopoietic developmental trajectories revealed potential functional roles for non-canonically activated CD4+ naïve T cells in newly-diagnosed pediatric cases of SAA. Furthermore, single-cell transcriptomic profiling highlighted a population of Th17-polarized CD4+CAMK4+ naïve T cells showing activation of the IL-6/JAK3/STAT3 pathway, while gene signature dissection indicated a predisposition to proinflammatory pathogenesis. Retrospective validation from our SAA cohort of 231 patients revealed high plasma levels of IL-6 as an independent risk factor of delayed hematopoietic response to antithymocyte globulin-based immunosuppressive therapy. Thus, IL-6 warrants further investigation as a putative therapeutic target in SAA.

Long-term outcomes of relmacabtagene autoleucel in Chinese patients with relapsed/refractory large B-cell lymphoma: Updated results of the RELIANCE study.

BACKGROUND AIMS: The RELIANCE study has demonstrated the activity and safety of relmacabtagene autoleucel (relma-cel) (JW Therapeutics [Shanghai] Co, Ltd, Shanghai, China), a CD19-targeted chimeric antigen receptor T-cell product, in patients with heavily pre-treated relapsed/refractory large B-cell lymphoma (r/r LBCL). This study aimed to report the updated 2-year data of the RELIANCE study. METHODS: The RELIANCE study (NCT04089215) was an open-label, multi-center, randomized, phase 1/2 registrational clinical trial conducted at 10 clinical sites in China. Adult patients with heavily pre-treated r/r LBCL were enrolled and received lymphodepletion chemotherapy followed by infusion of 100 × 106 or 150 × 106 relma-cel. The primary endpoint was objective response rate (ORR) at 3 months, as assessed by investigators. Secondary endpoints were duration of response (DoR), progression-free survival (PFS), overall survival (OS) and safety profiles. RESULTS: From November 2017 to January 2022, a total of 68 patients were enrolled, and 59 patients received relma-cel infusion. As of March 29, 2022, a total of 59 patients had a median follow-up of 17.9 months (range, 0.3-25.6). ORR was 77.59% (95% confidence interval [CI], 64.73-87.49) and complete response rate was 53.45% (95% CI, 39.87-66.66). Median DoR was 20.3 months (95% CI, 4.86-not reached [NR]) and median PFS was 7.0 months (95% CI, 4.76-24.15). Median OS was NR and 1-year and 2-year OS rates were 75.0% and 69.3%, respectively. Three (5.1%) patients experienced grade ≥3 cytokine release syndrome and two (3.4%) patients had grade ≥3 neurotoxicity. CONCLUSIONS: The updated data of the RELIANCE study demonstrate durable response with and manageable safety profile of relma-cel in patients with heavily pre-treated r/r LBCL.

Selpercatinib monotherapy in a Chinese patient with RET fusion/ EGFR co-mutated nonsmall cell lung cancer from the Phase II LIBRETTO-321 study: a case report.

Rearranged during transfection ( RET ) fusions and epidermal growth factor receptor ( EGFR ) mutations are potent oncogenic drivers in patients with nonsmall cell lung cancer (NSCLC), but rarely co-exist. Concurrent RET/EGFR mutations have been reported in patients with NSCLC who develop resistance to EGFR tyrosine kinase inhibitors but are even less frequent in treatment-naïve patients. Consequently, there is no standard treatment for RET/EGFR -mutated NSCLC. We report a case of RET/EGFR mutant NSCLC successfully treated with the oral, potent, highly selective RET inhibitor selpercatinib (160 mg daily for 28-day cycles) in an ongoing phase II study in Chinese patients with NSCLC (LIBRETTO-321). The patient, a female nonsmoker, was diagnosed with de-novo left lung adenocarcinoma with neuroendocrine differentiation, and a RET fusion was detected by next-generation sequencing testing. The patient had two tumors in the pleura, a third in the subcarinal lymph node, and a nontarget tumor in the pleura. Pleural biopsy analysis confirmed a RET fusion KIF5B (K15;R12) and an EGFR exon 19 deletion. The patient achieved a partial response (PR) with selpercatinib (absence of target tumors in pleura and reduction in the size of lymph node tumor). The PR persisted for 14.7 months, with disease progression in the nontarget lesion in the pleura and a new lesion in the liver (the PR had persisted), resulting in the discontinuation of selpercatinib. The only notable adverse event was grade 3 elevated transaminase, that was effectively managed by dose reduction. These data may support the use of selpercatinib in patients with RET/EGFR co-mutated NSCLC.