Li Zhang

Cancer-associated fibroblasts (CAFs) represent a major structural component of solid tumors and play crucial roles in cancer progression and drug resistance. However, their developmental origin, differentiation trajectory, and therapeutic potential remain poorly defined. Using advanced approaches—including inducible genetic lineage tracing, single-cell RNA sequencing, and spatial transcriptomic profiling—we identified a population of Cd34 ⁺ Pi16 ⁺ fibroblast progenitors (Cd34 ⁺ CAFs) in both melanoma and gastric cancer. We delineated their differentiation trajectory toward Acta2 ⁺ CAFs, driven by the upregulation of the transcription factor Foxs1. This work establishes the developmental origin of Acta2 ⁺ CAFs and experimentally validates the Cd34 ⁺ to Acta2 ⁺ transition. By reverse-matching the transcriptional signatures of Acta2 ⁺ CAF differentiation with the CMap/LINCS L1000 drug perturbation database, we identified four small-molecule candidates predicted to inhibit tumor-induced Foxs1 upregulation. These compounds effectively suppressed Cd34 ⁺ CAF differentiation, maintaining the progenitor-like Cd34 ⁺ state. Collectively, this study proposes a novel antitumor strategy that targets CAF lineage development to restrain tumor progression.

Elevated prenatal androgen levels have been associated with an increased incidence of several neurodevelopmental conditions in offspring. However, the underlying mechanisms remain poorly understood. Here we showed that elevated prenatal androgens, modeled via aromatase inhibition in mice, disrupt cortical development and behavior in male offspring by activating androgen receptors (AR). AR interacts with MeCP2 to upregulate the transcription factor MEF2C, bypassing standard androgen response elements. Knocking down Mecp2 or Mef2c, or blocking AR, reversed these effects. Mecp2 duplication alone also upregulated MEF2C, driving similar neurogenesis and behavioral changes that were reversed by AR blockade. This reveals a MeCP2-mediated, non-canonical pathway by which androgens may contribute to male-biased neurodevelopmental conditions.

BACKGROUND: Fibrosis is one of the major causes of cardiac allograft malfunction and is mainly driven by fibroblasts. However, the role of recipient-derived cells in generating allograft fibroblasts and the underlying mechanisms remain to be explored. METHODS: We analyzed human heart allograft samples and used murine transplant models (C57BL/6J, Cd34 (cluster of differentiation 34)-CreER ^T2 ; R26-tdTomato, mRFP (cell membrane labeled with red fluorescence protein) mice, Rosa26-iDTR, Postn -CreER ^T2 ; R26-tdTomato, double-tdTomato, and immunodeficient mice with BALB/c donors). Human progenitor cells were cultivated from blood. Single-cell RNA sequencing, Western blotting, quantitative polymerase chain reaction, and immunohistochemistry, whole-mount staining with 3-dimensional reconstruction, and in vivo / in vitro experiments were applied to characterize allograft cellular composition and communication. RESULTS: Single-cell RNA sequencing was introduced to delineate the allograft cell atlas of patients and mice. Y chromosome analysis identified that recipient-derived cells contributed to allograft fibroblasts in both patients and murine models. Combining the genetic cell lineage tracing technique, we found that recipient-derived CD34 ⁺ cells could give rise to activated fibroblasts. Bone marrow transplantation and parabiosis models revealed that the recipient's circulating non–bone marrow Cd34 ⁺ cells could generate allograft fibroblasts. Human CD34 ⁺ cells could differentiate into fibroblasts both in vivo and in vitro. CD34 ⁺ fibroblast progenitors were recruited by CXCL12 (C-X-C motif chemokine ligand 12)-ACKR3 (atypical chemokine receptor 3) and MIF (macrophage migration inhibitory factor)-ACKR3 interactions and differentiated via the TGFβ (transforming growth factor beta)/GFPT2 (glutamine-fructose-6-phosphate transaminase 2)/SMAD2/4 (small mother against decapentaplegic 2/4) axis. Ablation of recipient Cd34 ⁺ cells reduced activated fibroblasts and alleviated allograft fibrosis. CONCLUSIONS: We identify circulating CD34 ⁺ cells as a novel source of fibroblast progenitors that contribute to cardiac allograft fibrosis, suggesting that targeting recipient CD34 ⁺ cells could be a novel therapeutic potential for treating cardiac fibrosis after heart transplantation.

Patients with chronic kidney disease (CKD) are recognized as a higher risk group for cardiovascular disease (CVD) due to various traditional risk factors, kidney-specific factors, and comorbidities, which have recently attracted significant attention. However, the long-term risk of acute CVD events such as sudden cardiac death (SCD) in CKD patients is unclear. Using the UK Biobank and Changsha cohorts, we find that CKD is associated with an increased risk of SCD. Patients with early-stage CKD, especially those with advanced CKD, faced an elevated risk of SCD. Furthermore, through proteomic analyses of the UK Biobank and Framingham Offspring Cohort, we identify five candidate proteins (NTproBNP, ANGPT2, FGF23, DTNB, and SEPTIN8) linked to SCD risk in CKD patients. Here, we show that patients with CKD have an increased risk of SCD in the long term, underscoring the imperative for strategies that address both cardiovascular risk and renal function in this population.

The global incidence of obesity-related metabolic disorders and their comorbidities continue to increase along with a demand for innovative therapeutic interventions. An in-depth understanding of de novo thermogenic adipogenesis is vital to harness the potential of these adipocytes. Here, we combine genetic lineage tracing and single-nucleus RNA sequencing to demonstrate that adult adipose-resident c-kit⁺ cells are previously unidentified brown adipocyte progenitor cells (APCs). c-kit⁺ APCs differentiate into brown adipocytes but not white adipocytes in adipose tissue homeostasis as well as in cold exposure-, high-fat diet (HFD)- and aging-induced adipose remodeling. More importantly, the vital role of c-kit⁺ APCs in the generation of brown adipocytes is indicated by decreased brown fat, impaired thermogenic capacity, and excessive fat accumulation in c-kit mutant mice of both genders. In conclusion, the present study demonstrates that adult c-kit⁺ APCs give rise to brown adipocytes which are responsible for fat homeostasis and remodeling. Thus, c-kit⁺ progenitors may be an innovative and crucial target for obesity and metabolic diseases.

Aims: Neointimal hyperplasia (NIH) characterized by vascular smooth muscle cell (VSMC) dysfunctions plays a critical role in many vascular diseases including atherosclerosis and restenosis, which leads to serious ischaemic complications and has limited therapeutic approaches. Our previous studies confirm a critical role for nuclear factor erythroid 2-related factor 3 (Nrf3) in VSMC differentiation. However, little is known about the functional implications of Nrf3 in NIH. Methods and results: Transcriptome dataset and human atherosclerotic samples were used to determine Nrf3 expression levels. Global (Nrf3−/−) and VSMC-specific (Nrf3ΔSMC) Nrf3 knockout mice were used to assess the role of Nrf3 in VSMC function and injury-induced NIH. Complementary molecular methods were performed to identify Nrf3 downstream targets and elucidate the regulatory role of Nrf3 in target gene regulation. Porcine carotid stenting model was used to validate the therapeutic effects of Nrf3 inhibition in vascular remodelling. Transcriptomic data and immunostaining analysis showed increased levels of Nrf3, and a positive correlation between Nrf3 and NIH in the human atherosclerotic vessels. Various pathophysiological stimuli induced endoplasmic reticulum stress that enhanced Nrf3 expression via Activating Transcription Factor 4 (ATF4). Nrf3 overexpression promoted both human and mouse VSMC proliferation, migration, and inflammatory response, while opposite effects were observed when Nrf3 was deleted or knockdown. Nrf3−/− and Nrf3ΔSMC mice showed decreased VSMC accumulation and attenuated vascular injury-induced NIH. Mechanistically, tripartite motif-containing 5 (Trim5), a genetic risk locus for coronary artery disease, was identified as a functional downstream target of Nrf3 in VSMCs and in injured arteries. Nrf3 enhanced autophagy in VSMCs and injured arteries by up-regulating Trim5 expression, which subsequently promoted dysfunctions of VSMCs, thereby increasing injury-induced NIH. Importantly, restoring either Nrf3 or Trim5 expression in Nrf3−/− mice rescued the arterial phenotypes observed in Nrf3−/− mice. Critically, the porcine carotid artery restenosis induced by ballooning and stenting was significantly reduced by suppressing Nrf3 expression through perivascular administration of the Nrf3 inhibitors. Conclusions: We comprehensively demonstrate that Nrf3 is a novel modulator in VSMC dysfunctions and injury-induced NIH. Nrf3 exerts its pathological functions by transcriptional activation of Trim5 gene, which in turn triggers autophagy in VSMCs and injured arteries, promoting arterial remodelling. Inhibiting the Nrf3–Trim5 signal axis ameliorates injury-induced NIH, offering novel therapeutics for treating patients with NIH-related vascular diseases.

BACKGROUND: Myocardial infarction (MI) elicits mitochondria reactive oxygen species (ROS) production and cardiomyocyte (CM) apoptosis. Nrf3 (nuclear factor erythroid 2-related factor 3) has an established role in regulating redox signaling and tissue homeostasis. Here, we aimed to evaluate the role and mechanism of Nrf3 in injury-induced pathological cardiac remodeling. METHODS: Global (Nrf3-KO) and CM-specific (Nrf3 ^△CM ) Nrf3 knockout mice were subjected to MI or ischemia/reperfusion injury, followed by functional and histopathological analysis. Primary neonatal mouse and rat ventricular myocytes and CMs derived from human induced pluripotent stem cells were used to evaluate the impact of Nrf3 on CM apoptosis and mitochondrial ROS production. Chromatin immunoprecipitation sequencing and immunoprecipitation–mass spectrometry analysis were used to uncover potential targets of Nrf3. MitoParaquat administration and CM-specific adeno-associated virus vectors were used to further confirm the i n vivo relevance of the identified signal pathways. RESULTS: Nrf3 was expressed mainly in CMs in healthy human hearts, and an increased level of Nrf3 was observed in CMs within the border zone of infarcted human hearts and murine cardiac tissues after MI. Both global and CM-specific Nrf3 knockout significantly decreased injury-induced mitochondrial ROS production, CM apoptosis, and pathological cardiac remodeling, consequently improving cardiac functions. In addition, cardiac-specific Nrf3 overexpression reversed the ameliorative cardiac phenotypes observed in Nrf3-KO mice. Functional studies showed that Nrf3 promoted neonatal mouse ventricular myocyte, neonatal rat ventricular myocyte, and CMs derived from human induced pluripotent stem cell apoptosis by increasing mitochondrial ROS production. Critically, augmenting mitochondrial ROS with MitoParaquat blunted the beneficial effects of Nrf3 deletion on cardiac function and remodeling. Mechanistically, a redox regulator Pitx2 (paired-like homeodomain transcription factor 2) was identified as one of the main target genes of Nrf3. Specifically, Nrf3 binds to Pitx2 promoter, where it increases DNA methylation through recruiting heterogeneous nuclear ribonucleoprotein K and DNA-methyltransferase 1 complex, thereby inhibiting Pitx2 expression. CM-specific knockdown of Pitx2 blunted the beneficial effects of Nrf3 deletion on cardiac function and remodeling, and cardiac-specific Pitx2 overexpression attenuated MI-induced mitochondrial ROS production and CM apoptosis, as well as preserved cardiac functions after MI. CONCLUSIONS: Nrf3 promotes injury-induced CM apoptosis and deteriorates cardiac functions by increasing mitochondrial ROS production through suppressing Pitx2 expression. Targeting the Nrf3–Pitx2–mitochondrial ROS signal axis may therefore represent a novel therapeutic approach for MI treatment.

Rationale: Transplant-accelerated arteriosclerosis is a common complication that limits the long-term survival of organ transplant recipients. While previous studies have indicated the involvement of CD34⁺ stem/progenitor cells (SPCs) in this process, their heterogeneity and potential adverse effects remains incompletely understood.

BACKGROUND: Coronary microvascular dysfunction has been implicated in the development of hypertensive heart disease and heart failure, with subendocardial ischemia identified as a driver of sustained myocardial injury and fibrosis. We aimed to evaluate the relationships of subendocardial perfusion with cardiac injury, structure, and a composite of major adverse cardiac and cerebrovascular events consisting of death, heart failure hospitalization, myocardial infarction, and stroke. METHODS: Layer-specific blood flow and myocardial flow reserve (MFR; stress/rest myocardial blood flow) were assessed by ¹³ N-ammonia perfusion positron emission tomography in consecutive patients with hypertension without flow-limiting coronary artery disease (summed stress score subendo ). RESULTS: Among 358 patients, the mean age was 70.6±12.0 years, and 53.4% were male. The median MFR _subendo was 2.57 (interquartile range, 2.08–3.10), and lower MFR _subendo was associated with older age, diabetes, lower renal function, greater coronary calcium burden, and higher systolic blood pressure ( P subendo was associated with myocardial injury and with greater left ventricular wall thickness and volumes compared with the highest tertile. Relative to the highest tertile, low MFR _subendo was independently associated with an increased rate of major adverse cardiac and cerebrovascular events (adjusted hazard ratio, 2.99 [95% CI, 1.39–6.44]; P =0.005) and heart failure hospitalization (adjusted hazard ratio, 2.76 [95% CI, 1.04–7.32; P =0.042) over 1.1 (interquartile range, 0.6–2.8) years median follow-up. CONCLUSIONS: Among patients with hypertension without flow-limiting coronary artery disease, impaired MFR _subendo was associated with cardiovascular risk factors, elevated cardiac biomarkers, cardiac structure, and clinical events.

BACKGROUND: Thoracic aortic dissection (TAD) is a life-threatening aortic disease without effective medical treatment. Increasing evidence has suggested a role for NE (neutrophil elastase) in vascular diseases. In this study, we aimed at investigating a causal role for NE in TAD and exploring the molecular mechanisms involved. METHODS: β-aminopropionitrile monofumarate was administrated in mice to induce TAD. NE deficiency mice, pharmacological inhibitor GW311616A, and adeno-associated virus-2–mediated in vivo gene transfer were applied to explore a causal role for NE and associated target gene in TAD formation. Multiple functional assays and biochemical analyses were conducted to unravel the underlying cellular and molecular mechanisms of NE in TAD. RESULTS: NE aortic gene expression and plasma activity was significantly increased during β-aminopropionitrile monofumarate–induced TAD and in patients with acute TAD. NE deficiency prevents β-aminopropionitrile monofumarate–induced TAD onset/development, and GW311616A administration ameliorated TAD formation/progression. Decreased levels of neutrophil extracellular traps, inflammatory cells, and MMP (matrix metalloproteinase)-2/9 were observed in NE-deficient mice. TBL1x (F-box-like/WD repeat-containing protein TBL1x) has been identified as a novel substrate and functional downstream target of NE in TAD. Loss-of-function studies revealed that NE mediated inflammatory cell transendothelial migration by modulating TBL1x-LTA4H (leukotriene A4 hydrolase) signaling and that NE regulated smooth muscle cell phenotype modulation under TAD pathological condition by regulating TBL1x-MECP2 (methyl CpG-binding protein 2) signal axis. Further mechanistic studies showed that TBL1x inhibition decreased the binding of TBL1x and HDAC3 (histone deacetylase 3) to MECP2 and LTA4H gene promoters, respectively. Finally, adeno-associated virus-2–mediated Tbl1x gene knockdown in aortic smooth muscle cells confirmed a regulatory role for TBL1x in NE-mediated TAD formation. CONCLUSIONS: We unravel a critical role of NE and its target TBL1x in regulating inflammatory cell migration and smooth muscle cell phenotype modulation in the context of TAD. Our findings suggest that the NE-TBL1x signal axis represents a valuable therapeutic for treating high-risk TAD patients.