Extracellular vesicles derived from Cryptococcus neoformans promoted neutrophil extracellular traps.

Phase Ib of repotrectinib plus osimertinib in patients with EGFR-mutated advanced non-small cell lung cancer.

Acetaminophen (APAP) exposures during human development are common. Emerging epidemiological and experimental evidence links these exposures to subsequent pulmonary morbidity; however, the underlying mechanisms remain incompletely defined. Cell-type-specific expression of the xenobiotic enzyme CYP2E1 is a critical determinant of susceptibility to APAP toxicity. CYP2E1-mediated formation of the reactive metabolite N-acetyl-p-benzoquinone imine (NAPQI) induces mitochondrial injury, which can trigger sterile inflammation through Toll-like receptor 9 (TLR9)-dependent innate immune signaling. The developing mouse lung is particularly vulnerable to APAP exposure at postnatal day 14 (P14), a time point within peak alveologenesis that coincides with maximal pulmonary CYP2E1 expression; however, the role of TLR9 signaling in this developmental window has remained unclear. In a preclinical model, wild-type (WT) and TLR9 knockout (TLR9 KO) male and female mice received a single, nonhepatotoxic dose of APAP (140 mg/kg, ip) at P14. Acute lung injury occurred in both genotypes, but TLR9 deficiency reduced proinflammatory target gene (Il1b, Il6) expression and associated STAT3 activation and target gene (Mmp9, Ptgs2, Cxcl2, Bclxl, Pim1) expression. Although APAP-exposed WT mice demonstrated persistent structural and functional abnormalities at P28, attenuation of the early inflammatory response in TLR9 KO mice preserved lung architecture and pulmonary function. These findings identify TLR9-dependent innate immune activation as a mechanistic link between early-life APAP exposure and impaired lung development. The data further suggest that limiting inflammation during the critical window of alveologenesis may preserve normal lung maturation and reduce later pulmonary morbidity. Further studies are warranted to define the clinical relevance of these findings.NEW & NOTEWORTHY Acute lung injury following acetaminophen (APAP) exposures during the key developmental window of alveologenesis has been previously described. Here, we highlight that eliminating TLR9-mediated immune signaling and associated induction of key proinflammatory mediators attenuated impaired lung development and associated dysfunction. We propose that an underlying mechanism linked with sterile inflammation contributes to abnormal pulmonary development following APAP exposure, and that further investigation is necessary for application in a clinical environment.

Many bacterial immunotherapies, because of their intracellular lifestyle, have the potential to overcome the limitations that reduce the efficacy of immune checkpoint inhibitors. One reason this approach is not completely curative is the innate immune suppression of the bacteria. After cell invasion, Salmonella injects effector proteins that inhibit host cell signaling and suppress subsequent immune responses. To increase the efficacy of bacterial therapies we designed a CRISPRi (clustered regularly interspaced short palindromic repeats─interference) system to repress the expression of two Salmonella effectors, SopB and SteE. We hypothesized that repressing SopB decreases AKT phosphorylation and repressing SteE decreases STAT3 phosphorylation. For each effector, we optimized the response by creating multiple guide RNAs and evaluating their ability to repress expression of fluorescent fusion proteins. To characterize their biological effects, we administered these engineered bacteria to cancer cells and macrophages. In cancer cells, CRISPRi repression of SopB reduced activation of AKT and increased cellular apoptosis. In both cancer cells and macrophages, repression of SteE reduced activation of STAT3, reduced the secretion of immunosuppressive IL-10 and increased the secretion of pro-inflammatory TNF-α. Promotion of apoptosis and secretion of IL-10 are biological functions downstream of AKT and STAT3, respectively. The increased production of TNF-α was most likely mediated by the reduced levels of IL-10. These experiments show, for the first time, that CRISPRi modulation of effector expression in therapeutic Salmonella can control the physiology of mammalian cells and shift their phenotype to one that is less immunosuppressive and more favorable for cancer therapy.

Intestinal fibrosis presents a major clinical challenge in Crohn's disease (CD) due to the lack of effective pharmacological interventions. The underlying mechanisms of intestinal fibrosis remain largely elusive. Reanalysis of the single-cell RNA-seq data from full-thickness CD tissue identifies a distinct profibrotic macrophage subset characterized by high S100A8 and S100A9 expression. CellChat analysis indicates strong communication between this S100A8/A9-high (S100A8/A9hi) macrophage subset and fibroblasts. Adoptive transfer of S100A8/A9hi macrophages exacerbate intestinal fibrosis in mice with chronic dextran sulfate sodium (DSS)-induced colitis. Consequently, pharmacological inhibition of S100A8/A9 significantly ameliorates intestinal fibrosis in murine chronic colitis. Proteomic analysis further identifies murine CCL6 (mCCL6) as the key pro-fibrotic mediator secreted by S100A8/A9hi macrophages, which acts via CC chemokine receptor 1 (CCR1) to regulate fibroblasts. Antibody blockade of mCCL6 alleviates established intestinal fibrosis in a DSS-induced colitis model. Mechanistically, S100A8/A9hi macrophages drive mCCL6 production via STAT3 activation. Similarly, the human ortholog of CCL6, CCL15 (hCCL15), exerts pro-fibrotic effects on fibroblasts via the CCR1 receptor. Our findings reveal that targeting S100A8/A9hi macrophage may be a therapeutic strategy against intestinal fibrosis in CD.

Kv1.3 Modulates Macrophage M2 Polarization via the STAT3 Pathway: A Novel Mechanism and Therapeutic Target for Steroid-Resistant Asthma.

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disorder, characterized by metabolic reprogramming with enhanced glycolysis and lactate accumulation. However, the enzyme that senses lactate and uses it as a substrate for protein lactylation in ADPKD remains unknown. Alanyl-tRNA synthetase 1 (AARS1) is a lactate-responsive enzyme with lactyltransferase activity, while its role and mechanisms in ADPKD have not been defined. To investigate the role of AARS1, we generated Pkd1 and Aars1 double conditional knockout Pkd1fl/fl:Aars1fl/fl:Ksp-Cre mice and evaluated the effect of AARS1 inhibitor, β-alanine, in two ADPKD mouse models. Coimmunoprecipitation and CUT&Tag analyses were performed to identify novel AARS1 substrates and downstream target genes involved in cystogenesis. AARS1 was elevated in Pkd1 mutant renal epithelial cells and kidneys, and genetic deletion of Aars1 significantly delayed cyst growth, preserved kidney function, and reduced renal lactylation in Pkd1 mutant mice. Mechanistically, AARS1 promoted lactylation-dependent activation of STAT3 and NF-κB (p65), specifically at STAT3 K140 and p65 K310, thereby amplifying pro-proliferative and pro-inflammatory transcriptional programs. AARS1 also associated with promoter regions and mediated histone H3K14 lactylation, thereby repressing the transcription of Atg5 to impair autophagy and suppressing the transcription of Dusp4 to sustain phosphorylation of cAMP response element-binding protein (CREB) and retinoblastoma protein (Rb). Cytokine signaling via IL-6 and TNF-α further reinforced AARS1 expression through STAT3- and NF-κB-dependent feed-forward loops. Importantly, inhibition of AARS1 with β-alanine markedly slowed cyst progression in Pkd1 mutant mouse models. Our study identified AARS1 as a central metabolic sensor linking lactate-driven lysine lactylation to transcriptional, epigenetic, and signaling pathways that drive ADPKD progression.

RNF138 promotes cisplatin resistance and PD-L1-mediated immune evasion via JAK2/STAT3 activation in nasopharyngeal carcinoma.

Pulmonary arterial hypertension (PAH) is a progressive cardiopulmonary disease in which right ventricular (RV) dysfunction and remodeling are major determinants of poor prognosis. Interleukin-22 binding protein (IL-22BP), encoded by IL22RA2/Il22ra2, is an endogenous antagonist of IL-22, but its role in PAH-associated RV remodeling remains unclear. Here, we investigated whether IL-22BP regulates RV remodeling through the IL-22/STAT3 axis. Serum IL-22BP levels were reduced in patients with PAH. In experimental PAH, RV IL-22BP was decreased in Sugen5416/hypoxia (SuHx) and monocrotaline rat models, and both RV Il22ra2 mRNA and IL-22BP protein were reduced in SuHx mice. In the SuHx mouse model, systemic Il22ra2 deficiency aggravated PAH severity and RV remodeling, accompanied by enhanced RV IL-22/IL-22R1/STAT3 signaling and increased remodeling-associated transcripts related to hypertrophy, fibrosis, apoptosis, and proliferation. Conversely, AAV-mediated IL-22BP reconstitution with preferential cardiac expression attenuated RV hypertrophy and dysfunction and suppressed RV IL-22/STAT3 signaling. Pharmacological STAT3 inhibition with S3I-201 partially rescued the aggravated PAH and RV remodeling phenotype in SuHx-treated Il22ra2⁻/⁻ mice. Complementary H9C2 cell experiments showed that IL-22 enhanced Ang II-associated STAT3 activation and remodeling-related transcriptional responses, whereas S3I-201 attenuated several Ang II-induced remodeling signals. Lung analysis showed altered pulmonary IL-22/STAT3 signaling after SuHx exposure and Il22ra2 deficiency, but cardiac IL-22BP reconstitution did not significantly normalize these whole-lung markers. Th17-related immune changes paralleled disease severity and IL-22BP-associated improvement. Finally, treprostinil plus oridonin produced broader phenotypic improvement than either monotherapy and increased cardiac IL-22BP expression. These findings identify IL-22BP as a treatment-responsive endogenous regulator of PAH-associated RV remodeling.

The Huyan-I formula (HY-I), a patented six‑herb traditional Chinese medicine used clinically at Jiangsu Provincial Hospital of TCM for early‑stage chronic kidney disease (CKD), has demonstrated therapeutic efficacy; however, its molecular mechanisms remain unclear. Given the central role of cellular senescence and fibrosis in CKD progression, particularly through the senescence‑associated secretory phenotype (SASP), this study investigated whether HY-I ameliorates renal senescence and fibrosis by modulating SASP‑related signaling. By UPLC‑Q‑TOF-MS analysis, 211 components were identified in HY‑I, and 29 prototype compounds plus 19 metabolites were detected in the serum of HY‑I‑treated mice. Network pharmacology and molecular docking predictions indicated interactions with the STAT3/NF‑κB/NLRP3/SASP axis. In naturally aged mice and in D‑galactose‑induced senescent human renal tubular (HK‑2) cells treated with HY-I or resveratrol (positive control), HY-I significantly reduced senescent cell burden and senescence markers, suppressed activation of STAT3, NF‑κB, and NLRP3, downregulated SASP expression, and improved tubular injury and renal fibrosis as assessed by Western blot, immunohistochemistry, multiplex immunofluorescence, and histopathological staining (HE, Masson, PAS). These findings demonstrate that HY-I alleviates renal aging and fibrosis by inhibiting the STAT3/NF‑κB/NLRP3 pathway and attenuating the SASP, thereby providing a mechanistic basis for its clinical application in CKD.

STAT3 interference-driven nanomodulators reverse lipid metabolism-associated chemoresistance and potentiate metalloimmunotherapy in breast cancer.

Role of copper ion overload triggered by CD44 endocytosis on STAT3-mediated cuproptosis in septic myocardial injury.

Design, synthesis, and biological evaluation of clovamide analogues as anti-colitis agents modulating NF-κB/STAT3/iNOS signaling.

Neuroendocrine prostate cancer (NEPC) is a lethal subtype of prostate cancer (PCa) that emerges under androgen deprivation and is associated with therapeutic resistance. The contribution of volume-regulated anion channels (VRACs) to this process remains poorly understood. This study identified leucine-rich repeat-containing 8 subunit D (LRRC8D), a VRAC subunit, as the only family member consistently downregulated in NEPC and associated with neuroendocrine (NE)-like features. LRRC8D downregulation was accompanied by suppression of swelling-activated VRAC currents, increased synaptophysin (SYP) expression, decreased cisplatin sensitivity, and neurosecretory remodeling. Conversely, LRRC8D overexpression enhanced cisplatin-induced apoptosis, reduced colony formation, and suppressed tumor growth in xenograft models, including under cisplatin treatment. Consistent alterations in LRRC8D and SYP expression were also observed in enzalutamide-resistant patient-derived organoids. Mechanistically, RE1-silencing transcription factor (REST) promoted LRRC8D transcription. Functional analyses further demonstrated that CAV-1 acted upstream of LRRC8D, and LRRC8D negatively regulated STAT3 activation. Together, these findings indicate that LRRC8D influences PCa phenotype and platinum responsiveness, and implicate a regulatory axis involving LRRC8D and CAV-1/STAT3 signaling in NE-associated features of advanced PCa. Functional analyses further showed that CAV-1 acted upstream of LRRC8D, and LRRC8D negatively regulated STAT3 activation. Together, these findings indicate that LRRC8D influences PCa phenotype and platinum responsiveness and implicate a regulatory axis involving LRRC8D and CAV-1/STAT3 signaling in NE-associated features of advanced PCa.

3074-LB: Inhibition of VDAC1 Oligomerization Regulates Energy Balance through Hypothalamic STAT3 Activation in Mice

Microglia play crucial roles in Alzheimer's disease (AD), yet the molecular mechanisms are unclear. Here, we show that CD31, a recognized endothelial marker, is predominantly expressed in microglia but not in neurons or astrocytes, and it is significantly elevated in the brains of AD patients and mouse models. Microglia-specific CD31 knockdown in 5xFAD mice substantially attenuated the dysregulated transcription networks, suppressed microglia hyperactivation and the disease-associated microglia (DAM), mitigated Aβ deposition and inflammation, and eventually improved cognitive functions in mice. Mechanistically, CD31 knockdown damaged the simultaneous recruitment of Src homology phosphatase 2 (SHP2) and STAT3, leading to a reduced dephosphorylation and enhanced activation of STAT3, a transcription factor. STAT3 activation increased transcription of membrane metalloendopeptidase (MME) and promoted Aβ clearance. Collectively, this study identifies microglial CD31, by regulating SHP2-STAT3-MME axis, plays a role in AD pathogenesis and targeting CD31 is promising in AD drug development.

rFgl2-treated CD32b+M2 macrophages effectively inhibits cardiac transplant rejection in mice.

This study aimed to investigate the therapeutic potential of Colivelin in modulating the cross-talk between the IL-6/JAK2/STAT3 and TGF-β/SMAD2/SMAD3 signaling pathways and its downstream effects on retinal apoptosis in an in vitro AMD model. An in vitro AMD model was established in ARPE-19 human RPE cells using a sublethal combination of lipopolysaccharide and hydrogen peroxide. Apoptosis was quantified via Tali® image cytometry. Gene expression profiling was performed by qRT- PCR. Protein expressions were assessed by Western blot. Formal mediation analysis was employed to quantify pathway-specific mechanistic contributions. The AMD model exhibited significant upregulation of hypoxia-related genes (HIF-1α, VEGF, MMP3, MMP9), pro-inflammatory cytokines (IL-6, TNF-α), and pro-apoptotic markers (BAX, p53, Caspase- 3), accompanied by markedly elevated ROS levels and reduced cell viability. Low-dose Colivelin (1µM) significantly enhanced STAT3 phosphorylation, restored antioxidant gene expression (GSS, CAT, SOD2), suppressed hypoxia-associated gene expression, and substantially reduced TGF-β receptor, SMAD2, and SMAD3 expression at both transcriptional and protein levels. Formal mediation analysis revealed that 91-98% of Colivelin's anti-apoptotic effect at the therapeutic dose was mediated through STAT3-driven suppression of TGF-β/SMAD2/3 signaling, rather than through direct STAT3 transcriptional activity on apoptotic target genes. Conversely, high-dose Colivelin (10µM) paradoxically activated SMAD2/3-independent pro-apoptotic cascades, demonstrating a dose- dependent biphasic response. This study provides the first formal mechanistic evidence that Colivelin exerts its cytoprotective effects in AMD primarily through a STAT3 → SMAD2/3 suppression axis. Low-dose (1µM) Colivelin demonstrated superior and broader therapeutic efficacy compared to Bevacizumab by simultaneously modulating oxidative stress, hypoxia, angiogenesis, and apoptotic signaling pathways. These findings establish Colivelin as a promising multi-target therapeutic candidate for AMD, with its therapeutic window defined by the capacity of STAT3 activation to selectively suppress TGF-β/SMAD-driven apoptotic signaling without engaging compensatory pro-death mechanisms. Rigorous pharmacokinetic optimization and in vivo validation are warranted to advance Colivelin toward clinical translation.

Keratinocyte stem cells are essential for maintaining epidermal homeostasis and enabling efficient tissue repair. Regulation of their self-renewal and differentiation is critical, as its disruption can impair regeneration and drive pathological conditions such as chronic wounds and cancer. We previously identified the matricellular protein Mindin as a key regulator of keratinocyte stemness through its interaction with the αMβ2 (CD11b/CD18) integrin and subsequent activation of the transcription factor STAT3. However, the mechanism connecting Mindin and integrin at the cell surface to the intracellular activation of STAT3 remained undefined. We employ biochemical and imaging analysis along with molecular dynamics simulations to dissect Mindin-integrin-STAT3 signalling in primary mouse keratinocytes. Stemness of epidermal keratinocytes are assessed using bulk RNA sequencing, quantitative PCR, and cell-based assays. Our work demonstrates that the F-Spondin domain of Mindin constitutes the minimal integrin-binding module required to initiate downstream signalling. F-Spondin binding to the integrin at the plasma membrane does not elicit the full activation state of the integrin. Instead, it promotes Src-kinase dependent endocytosis of the integrin receptor to the early endosomes. Analysis of integrin conformational dynamics reveals that the acidic environment of early endosomes is essential to achieve a signalling-competent state. This mechanism extends to pathological contexts, as we demonstrate a requirement for endocytosis in activating STAT3 signalling and preserving stem-like properties in a cancer stem cell model. These findings highlight a previously unrecognized layer of spatial control in integrin signalling, confirming endosomal trafficking as a critical determinant of stem cell behaviour and offering new conceptual and therapeutic opportunities across regenerative biology and cancer.

Integrating network toxicology, molecular simulation and experimental validation to decipher the role of CXCR4 in benzalkonium chloride-induced parakeratosis.