Cardiac fibrosis is a defining pathological feature of diabetic cardiomyopathy (DCM), and excessive activation of cardiac fibroblasts plays a critical role in regulating cardiomyocyte function through paracrine signaling. CCN1 (cellular communication network factor 1), an extracellular matrix protein involved in intercellular communication, has been suggested to influence cardiac remodeling, although its specific impact on cardiomyocytes in DCM has remained unclear. In this study, we found that CCN1 expression was markedly elevated in cardiac tissues from DCM mouse models and in insulin-resistant cell models, with fibroblasts serving as the primary source. Proteomic analysis and co-culture experiments demonstrated that CCN1 suppressed cardiomyocyte macroautophagy/autophagy. To determine its role in vivo, we generated fibroblast-specific ccn1 knockout mice and established a DCM model, demonstrating that ccn1 deletion ameliorated cardiac dysfunction and restored autophagic activity. We further identified ITGAV-ITGB1/integrin αvβ1 as the receptor mediating CCN1 signaling in cardiomyocytes. Molecular dynamics simulations and co-immunoprecipitation experiments confirmed that CCN1 engaged ITGAV-ITGB1/integrin αvβ1 through its cysteine-knot-containing (CT) domain. Mechanistically, this interaction activated the downstream PTK2/FAK-MTOR signaling pathway, leading to inhibition of cardiomyocyte autophagy. Together, these findings reveal a previously unrecognized fibroblast-cardiomyocyte signaling axis in which fibroblast-derived CCN1 drives DCM progression by suppressing autophagy through ITGAV-ITGB1/integrin αvβ1-dependent signaling. This work provides mechanistic insight into the pathogenesis of DCM and identifies CCN1 as a potential therapeutic target for mitigating disease onset and progression.Abbreviations: AAV9: adeno-associated virus serotype 9; ADGRE1/EMR1/F4/80: adhesion G protein-coupled receptor E1; BafA1: bafilomycin A1; BSA: bovine serum albumin; C8: compound 8; CCN1: cellular communication network factor 1; CF: cardiac fibroblast; CSA: cross-sectional area; DCM: diabetic cardiomyopathy; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; ELISA: enzyme-linked immunosorbent assay; HE: hematoxylin and eosin; HFD: high-fat diet; HG: high glucose; IR: insulin resistance; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MD: molecular dynamics; MTOR: mechanistic target of rapamycin kinase; NRCM: neonatal rat cardiomyocyte; PDGFRA: platelet derived growth factor receptor alpha; PECAM1/CD31: platelet and endothelial cell adhesion molecule 1; PTK2/FAK: protein tyrosine kinase 2; PTPRC/CD45: protein tyrosine phosphatase receptor type C; RPS6KB1: ribosomal protein S6 kinase B1; S100A4/FSP1: S100 calcium binding protein A4; SQSTM1/p62: sequestosome 1; STZ: streptozotocin; TUNEL: terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling; WGA: wheat germ agglutinin.

OBJECTIVE:Fibro-adipogenic progenitor (FAP) dysfunction drives skeletal muscle fibrosis in type 2 diabetes mellitus (T2DM), yet the underlying metabolic-epigenetic mechanisms remain poorly understood. This study investigates how metabolite fluctuations regulate the cell fate of CD90+ FAPs in the diabetic skeletal muscles. METHODS AND RESULTS:Re-analysis of single-cell RNA sequencing data from human diabetic skeletal muscle, combined with immunofluorescence staining of biopsy specimens, revealed a significant expansion of CD90+ FAPs characterized by aberrant asymmetric cell division (ACD) associated polarity and a profibrotic phenotype. Using LC-MS, we identified a marked metabolic shift in insulin-resistant CD90+ FAPs, with reduced alpha-ketoglutarate (α-KG) and elevated L-2-hydroxyglutarate (L-2HG) levels. Reduced α-KG availability, together with competitive inhibition by accumulated L-2HG, suppresses TET2 activity and shifts DNA cytosine modification toward increased 5mC and decreased 5hmC. Specifically, epigenetic remodeling at the promoters of polarity-related genes-Pard3b, Pard6b, and Prkcz-was associated with activation of an ACD-related polarity program in CD90+ FAPs. This lineage bias promotes fibrogenic differentiation, ultimately exacerbating collagen accumulation and impairing muscle function. Dietary α-KG supplementation restored the α-KG/L-2HG ratio, restrained aberrant ACD-related polarity program, and effectively prevented or alleviated muscle fibrosis in T2DM mice. Conversely, TET2 knockdown attenuated the protective effects of α-KG on DNA hydroxymethylation and profibrotic activation of CD90+ FAPs, supporting a TET2-dependent mechanism underlying the epigenetic effects of α-KG. CONCLUSION:Our findings demonstrate that dysregulation of α-KG and L-2HG drives diabetic muscle fibrosis by disrupting TET2-dependent DNA hydroxymethylation and FAP division symmetry. Restoring this metabolic-epigenetic axis represents a promising therapeutic strategy for treating diabetic skeletal muscle fibrosis.

Cancer differentiation therapy aims to induce the maturation of neoplastic cells, but the mechanisms regulating cell fate decisions in oncogenic contexts remain unclear. In this study, we integrated single-cell chromatin accessibility and single-cell transcriptome analyses to explore the regulatory trajectories of a classical PML/RARα+ acute promyeloid leukemia (APL) cell line (NB4) post treatment by all-trans-retinoid acid (ATRA). Our findings indicated that ATRA activated specific PML/RARα-target enhancers to trigger a regulatory circuit composed of a positive feedforward gene regulatory circuit involving two transcription factors, SPI1 and CEBPE. This regulatory circuit was both necessary and sufficient to drive NB4 cells through an intermediate cell fate decision point to initiate terminal granulopoiesis. Moreover, ectopic expression of SPI1 and CEBPE promoted granulocytic differentiation in non-APL leukemia cell lines HL60 and K562. Our study sheds mechanistic insights into the differentiation trajectories induced by ATRA and illustrates a gene regulatory circuit that could be widely applied to promote differentiation of leukemia cells.

Somatic mutations in DNA methyltransferase 3 A (DNMT3A) are frequently observed in patients with hematological malignancies. Hematopoietic stem/progenitor cells (HSPCs) with mutated DNMT3A demonstrate increased self-renewal activity and skewed lineage differentiation. However, the molecular mechanisms underlying these changes remain largely unexplored. In this study, we show that Dnmt3a loss leads to the upregulation of endogenous retroviruses (ERVs) in HSPCs, subsequently activating the cGAS-STING pathway and triggering inflammatory responses in these cells. Both genetic and pharmacological inhibition of STING effectively corrects the increased self-renewal activity and differentiation skewing induced by Dnmt3a deficiency in mice. Notably, targeting STING showed inhibited acute myeloid leukemia (AML) development in a Dnmt3a-KO; Flt3-ITD AML model, comparable to AC220, an FDA-approved FLT3-ITD inhibitor. A patient-derived xenograft (PDX) model further demonstrated that targeting STING effectively alleviates the leukemic burden of DNMT3A-mutant AML. Collectively, our findings highlight a critical role for STING in hematopoietic disorders induced by DNMT3A mutations and propose STING as a potential therapeutic target for preventing the progression of DNMT3A mutation-associated leukemia.

Mitochondrial dysfunction is increasingly recognized as a driver of sarcopenia pathogenesis, progression, and prognosis. Muscle mass is a fundamental and objective component of sarcopenia. In some studies, relative muscle loss has been used to define sarcopenia. Methylmalonic acid (MMA) is a biomarker of mitochondrial dysfunction and vitamin B12 deficiency. Evidence has shown a negative link between MMA and muscle function, yet population-level evidence on its predictive and prognostic value in low muscle mass and sarcopenia remains scarce. This cohort study analyzes 10,414 U.S. adults from the National Health and Nutrition Examination Survey. Incidence of low muscle mass is evaluated with adjusted logistic regression, while all-cause mortality risk in this population is assessed using Cox regression and Kaplan-Meier analysis. Restricted cubic splines (RCS) model MMA-mortality dose-response. Subgroup and sensitivity analyses test robustness. After full covariate adjustment, elevated MMA level independently predicts low muscle mass incidence (OR = 1.30, 95% CI: 1.08-1.56, p = 0.007) and all-cause mortality (HR = 2.17, 95% CI: 1.64-2.89, p < 0.001) in this population. RCS analysis demonstrates a monotonic mortality increase with rising MMA concentrations (p for overall < 0.001), with no evidence of nonlinearity (p for nonlinear = 0.057). Kaplan-Meier survival curve exhibits significant mortality divergence across MMA tertiles (log-rank p < 0.001), especially in the elder low muscle mass population. Subgroup analysis identifies higher mortality associations in lifetime alcohol abstainers (HR = 3.60, 95% CI: 2.34-5.53, p < 0.001) and diabetic/borderline populations (HR = 3.49, 95% CI: 2.35-5.20, p < 0.001) with low muscle mass. Notably, MMA has significant interaction effects with congestive heart failure (p for interaction = 0.002). Sensitivity analysis corroborates the robustness of these associations. Serum MMA could serve as a dual biomarker for independently predicting low muscle mass incidence and post-diagnosis mortality. These findings underscore the clinical utility for early risk detection and prognosis stratification as well as call for trials targeting MMA reduction to mitigate sarcopenia pathogenesis, progression, and prognosis.

There is increasing evidence that long non-coding RNAs (lncRNAs) play a crucial role in the development and progression of malignant tumors, particularly pancreatic cancer. In this study, the influence of the lncRNA TINCR on the behavior of human pancreatic cancer cells was investigated with the aim of deciphering its role in growth, migration, and invasion. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to investigate TINCR expression in pancreatic cancer cells. Ectopic expression of TINCR in PANC-1 cells was induced to evaluate the effects on cell viability and apoptosis, examining the apoptotic genes Bax and Bcl-2. Migration and invasion assays were used to measure the impact of TINCR on these cellular processes. In vivo studies using a xenograft mouse model examined the effects of TINCR on tumor growth, epithelial-to-mesenchymal transition (EMT) markers, and the Wnt/β-catenin signaling pathway. PANC-1 cells showed strikingly low TINCR expression compared to other pancreatic cancer cell lines. Ectopic TINCR expression reduced the viability of PANC-1 cells primarily by inducing apoptosis, as evidenced by increased Bax and decreased Bcl-2 expression. Overexpression of TINCR significantly increased the percentage of apoptotic cells. It also decreased the migration and invasion ability of PANC-1 cells, as demonstrated in wound healing and transwell assays. In addition, overexpression of TINCR-suppressed proteins is associated with the Wnt/β-catenin signaling pathway in PANC-1 cells. In the xenograft mouse model, overexpression of TINCR inhibited tumor growth, EMT markers, and proteins associated with the Wnt/β-catenin pathway. This study sheds light on the tumour-suppressive role of TINCR in PANC-1 cells and suggests its potential as a therapeutic target. These results shed light on the molecular mechanisms underlying the impact of TINCR on pancreatic cancer and offer promising opportunities for innovative therapeutic strategies to improve outcomes in this serious malignancy.

OBJECTIVES:To explore the current application of high-throughput drug sensitivity (HDS) testing in children with relapsed and refractory acute leukemia (RR-AL) and analyze the feasibility of salvage treatment plans. METHODS:A retrospective collection of clinical data from children with RR-AL who underwent HDS testing at the Department of Children's Hematology and Oncology of the First Affiliated Hospital of Zhengzhou University from November 2021 to October 2023 was conducted, followed by an analysis of drug sensitivity results and treatment outcomes. RESULTS:A total of 17 children with RR-AL underwent HDS testing, including 7 cases of relapsed refractory acute myeloid leukemia and 10 cases of relapsed refractory acute lymphoblastic leukemia. The detection rate of highly sensitive chemotherapy drugs/regimens was 53% (9/17), while the detection rate of moderately sensitive chemotherapy drugs/regimens was 100% (17/17). Among the 17 RR-AL patients with highly and moderately sensitive chemotherapy drugs and regimens, the MOACD regimen (mitoxantrone + vincristine + cytarabine + cyclophosphamide + dexamethasone) accounted for 100%, with the highest inhibition rate for single-agent mitoxantrone (94%, 16/17), and the highest inhibition rate for targeted therapy being bortezomib (94%, 16/17). Nine patients adjusted their chemotherapy based on HDS testing results, with 4 undergoing hematopoietic stem cell transplantation. Four patients achieved disease-free survival, while 5 died. Eight patients received empirical chemotherapy, with 2 undergoing hematopoietic stem cell transplantation; 4 achieved disease-free survival, while 4 died. CONCLUSIONS:HDS testing can identify highly sensitive drugs/regimens for children with RR-AL, improving the rate of re-remission and creating conditions for subsequent hematopoietic stem cell transplantation.

Lineage switch in B-acute lymphoblastic leukemia (B-ALL) patients is a rare event during CD19 chimeric antigen receptor (CAR)-T treatment. Some studies have reported KMT2A rearrangements (KMT2A-r) as a risk factor in lineage switch, but the underlying mechanism of non-KMT2A-r cases remains unclear. Here, we described two young adult B-ALL lineage switch cases without KMT2A-r. Our analysis revealed lineage-specific transcription factors and surface markers related alterations, while major gene mutations remain unchanged. By reconstructing developmental trajectories, B-progenitor-like blasts were found to be reprogrammed into myeloid blasts after CAR-T treatment. Interestingly, we observed the increase of BCOR / BCORL1 truncating mutation burden at myeloid relapse in both cases. By retrospective analysis, we found that BCOR / BCORL1 gene mutated patients possessed myeloid-related features, indicating it as a potential risk factor for lineage switch. In summary, we established a study paradigm about lineage switch by single-cell technologies, which may be applied to clinical practice.

OBJECTIVES:To investigate the clinical features and prognosis of childhood acute lymphoblastic leukemia (ALL) with CREBBP gene mutation. METHODS:A retrospective analysis was performed for the clinical data of 14 ALL children with CREBBP gene mutation who were admitted to Children's Hospital of the First Affiliated Hospital of Zhengzhou University from January 2016 to December 2023. RESULTS:The ALL patients with CREBBP gene mutation accounted for 1.5% (14/963) among all children diagnosed with ALL during the same period of time, among whom there were 4 boys (29%) and 10 girls (71%), with a median age of 4 years and 3.5 months. All children had an immunological type of B-cell ALL and concurrent mutations in other genes including NRAS, KRAS, ETV6, FLT3, PAX5, SH2B3, CDKN2A, and CDKN2B, and 4 children had karyotype abnormality. All 14 children received induction therapy with the VDLP regimen, with a complete remission (CR) rate of 79% (11/14) after the first course of treatment. Three children experienced bone marrow recurrence alone, with a recurrence rate of 21% (3/14), among whom 1 child achieved CR after blinatumomab therapy and 2 received bridging hematopoietic stem cell transplantation after chemotherapy for recurrence. Among the 14 children, 1 died due to treatment discontinuation and 13 achieved disease-free survival. The 5-year overall survival rate was 92%±7%, and the event-free survival rate was 73%±13%. CONCLUSIONS:ALL with CREBBP gene mutation is more common in girls and has a low induction remission rate and a high recurrence rate, and it is often accompanied by other types of gene mutations and abnormal karyotypes. Most children with recurrence can achieve long-term survival after immunotherapy or hematopoietic stem cell transplantation.

DNA methylation plays a critical role in hematopoietic differentiation. Epimutation is a stochastic variation in DNA methylation that induces epigenetic heterogeneity. However, the effects of epimutations on normal hematopoiesis and hematopoietic diseases remain unclear. In this study, we developed a Julia package called EpiMut that enabled rapid and accurate quantification of epimutations. EpiMut was used to evaluate and provide an epimutation landscape in steady-state hematopoietic differentiation involving 13 types of blood cells ranging from hematopoietic stem/progenitor cells to mature cells. We showed that substantial genomic regions exhibited epigenetic variations rather than significant differences in DNA methylation levels between the myeloid and lymphoid lineages. Stepwise dynamics of epimutations were observed during the differentiation of each lineage. Importantly, we found that epimutation significantly enriched signals associated with lineage differentiation. Furthermore, epimutations in hematopoietic stem cells (HSCs) derived from various sources and acute myeloid leukemia were related to the function of HSCs and malignant cell disorders. Taken together, our study comprehensively documented an epimutation map and uncovered its important roles in human hematopoiesis, thereby offering insights into hematopoietic regulation.

To understand the molecular basis of heterogeneous hematopoietic stem cells (HSCs) is challenging. Especially, how a limited number of HSCs re-establish the HSC pool in myeloablated mice, and their molecular program regulating the reconstitution output remains elusive. Here, we tracked the clonal reconstitution by single-cell transplantation with single-cell RNA sequencing. Combining functional, immunophenotypical, and transcriptional assays, we found initial HSC clones expanded most significantly within a month and reached a plateau by 4 months, followed by gradual yet variable and fluctuated accumulation by 12 months after transplantation.Using hierarchical single-cell Bayesian model, the reconstitution and multilineage differentiation capabilities in single clones were evaluated during serial transplantation.There kinds of clones named Super, Flash, and Trickle were identified with distinct molecular features. Super HSC clones sustained higher level of multi-lineage reconstitution. Flash of lighting clones exhausted immediately after primary transplantation and exhibited a limited lymphoid-biased lineage output thereafter. Trickle clones continuously maintained low level of reconstitution.Super clone-derived HSCs were located on the apex of the hematopoietic hierarchty and specifically expressed genes involved in aerobic respiration, translation, and protein folding. To purify Super HSCs, we are currently testing candidate makers, for instance CD27 and CD74. Collectively, we revealed the establishment process of HSC compartment after transplantation and identified serially transplantable HSCs at the clonal level, providing promising target cells for in vivo and in vitro expansion of HSCs.

Graft failure is a fatal complication following allogeneic stem cell transplantation where a second transplantation is usually required for salvage. However, there are no recommended regimens for second transplantations for graft failure, especially in the haploidentical transplant setting. We recently reported encouraging outcomes using a novel method (haploidentical transplantation from a different donor after conditioning with fludarabine and cyclophosphamide). Herein, we report updated outcomes in 30 patients using this method. The median time of the second transplantation was 96.5 (33-215) days after the first transplantation. Except for one patient who died at +19d and before engraftment, neutrophil engraftments were achieved in all patients at 11 (8-24) days, while platelet engraftments were achieved in 22 (75.8%) patients at 17.5 (9-140) days. The 1-year OS and DFS were 60% and 53.3%, and CIR and TRM was 6.7% and 33.3%, respectively. Compared with the historical group, neutrophil engraftment (100% versus 58.5%, p < 0.001) and platelet engraftment (75.8% versus 32.3%, p < 0.001) were better in the novel regimen group, and OS was also improved (60.0% versus 26.4%, p = 0.011). In conclusion, salvage haploidentical transplantation from a different donor using the novel regimen represents a promising option to rescue patients with graft failure after the first haploidentical transplantation.

Inherited non-hemolytic anemia is a group of rare bone marrow disorders characterized by erythroid defects. Although concerted efforts have been made to explore the underlying pathogenetic mechanisms of these diseases, the understanding of the causative mutations are still incomplete. Here we identify in a diseased pedigree that a gain-of-function mutation in toll-like receptor 8 (TLR8) is implicated in inherited non-hemolytic anemia. TLR8 is expressed in erythroid lineage and erythropoiesis is impaired by TLR8 activation whereas enhanced by TLR8 inhibition from erythroid progenitor stage. Mechanistically, TLR8 activation blocks annexin A2 (ANXA2)-mediated plasma membrane localization of STAT5 and disrupts EPO signaling in HuDEP2 cells. TLR8 inhibition improves erythropoiesis in RPS19+/− HuDEP2 cells and CD34+ cells from healthy donors and inherited non-hemolytic anemic patients. Collectively, we identify a gene implicated in inherited anemia and a previously undescribed role for TLR8 in erythropoiesis, which could potentially be explored for therapeutic benefit in inherited anemia.

Background: The chemotherapeutic doxorubicin (DOX) promotes severe skeletal muscle atrophy, which induces skeletal muscle weakness and fatigue. Soluble guanylate cyclase (sGC) contributes to a variety of pathophysiological processes, but whether it is involved in DOX-induced skeletal muscle atrophy is unclear. The present study aimed to stimulate sGC by vericiguat, a new oral sGC stimulator, to test its role in this process.Methods: Mice were randomly divided into four groups: control group, vericiguat group, DOX group, and DOX + vericiguat group. Exercise capacity was evaluated before the mice were sacrificed. Skeletal muscle atrophy was assessed by histopathological and molecular biological methods. Protein synthesis and degradation were monitored in mice and C2C12 cells.Results: In this study, a significant decrease in exercise capacity and cross-sectional area (CSA) of skeletal muscle fibers was found in mice following DOX treatment. Furthermore, DOX decreased sGC activity in mice and C2C12 cells, and a positive correlation was found between sGC activity and CSA of skeletal muscle fibers in skeletal muscle. DOX treatment also impaired protein synthesis, shown by puromycin detection, and activated ubiquitin-proteasome pathway. Following sGC stimulation, the CSA of muscle fibers was elevated, and exercise capacity was enhanced. Stimulation of sGC also increased protein synthesis and decreased ubiquitin-proteasome pathway. In terms of the underlying mechanisms, AKT/mTOR and FoxO1 pathways were impaired following DOX treatment, and stimulation of sGC restored the blunted pathways.Conclusion: These results unravel sGC stimulation can improve skeletal muscle atrophy and increase the exercise capacity of mice in response to DOX treatment by enhancing protein synthesis and inhibiting protein degradation. Stimulation of sGC may be a potential treatment of DOX-induced skeletal muscle dysfunction.

Introduction: The energy imbalance when energy intake exceeds expenditure acts as an essential factor in the development of insulin resistance (IR). The activity of brown adipose tissue, which is involved in the dissipation of energy via heat expenditure decreases under type 2 diabetic mellitus (T2DM) state when the number of pathological aging adipocytes increases. Protein tyrosine phosphatase non-receptor type 2 (PTPN2) regulates several biological processes by dephosphorylating several cellular substrates; however, whether PTPN2 regulates cellular senescence in adipocytes and the underlying mechanism has not been reported. Methods: We constructed a model of type 2 diabetic mice with PTPN2 overexpression to explore the role of PTPN2 in T2DM. Results: We revealed that PTPN2 facilitated adipose tissue browning by alleviating pathological senescence, thus improving glucose tolerance and IR in T2DM. Mechanistically, we are the first to report that PTPN2 could bind with transforming growth factor-activated kinase 1 (TAK1) directly for dephosphorylation to inhibit the downstream MAPK/NF-κB pathway in adipocytes and regulate cellular senescence and the browning process subsequently. Discussion: Our study revealed a critical mechanism of adipocytes browning progression and provided a potential target for the treatment of related diseases.