Citations

ABSTRACT Glucagon‐like peptide‐1 (GLP‐1) receptor agonists (GLP‐1 RAs) improve glycaemia and reduce body weight, yet their organ‐level actions on skeletal muscle remain incompletely defined. Framing skeletal muscle as an integrated unit of vasculature and muscle cells, we synthesize evidence with emphasis on glucose and protein metabolism. GLP‐1 and GLP‐1 RAs recruit microvasculature in muscle, expanding capillary surface area and increasing delivery of insulin, glucose, and amino acids. Microvascular recruitment increases interstitial insulin availability and potentiates insulin‐stimulated glucose uptake and glycogen synthesis, whereas direct effects of GLP‐1 on muscle cells remain under investigation. For protein metabolism, microvascular recruitment can enhance muscle protein synthesis when plasma amino acid availability is elevated, whereas effects under basal (fasted) conditions remain unclear. Elucidating the uncertainty regarding GLP‐1 receptor localization in human muscle cells will clarify whether direct signaling occurs within muscle cells, thereby improving our understanding of the relative contribution of direct versus perfusion‐mediated actions of GLP‐1 RAs. Clinically, GLP‐1 RAs reduce lean body mass, likely reflecting energy‐deficit–mediated effects, but studies directly assessing muscle mass are still limited. Overall, current evidence indicates that GLP‐1 RAs exert beneficial effects on muscle vasculature and muscle glucose metabolism. However, their influence on muscle protein turnover remains unclear—primarily due to observed reductions in muscle mass—despite preclinical data suggesting potential favorable effects on muscle protein metabolism that remain to be confirmed in humans.

Abstract Acute kidney injury (AKI) causes rapid loss of renal function with high morbidity and mortality. Our previous research showed that neuronal nitric oxide synthase (NOS1) mediates nitric oxide-dependent dilation of the afferent arteriole, inhibiting tubuloglomerular feedback (TGF), which critically regulates single nephron glomerular filtration rate (GFR). This mechanism could affect how vulnerable the organ is to ischemic injury, but this has not been directly tested. In the present study, we generated inducible macula densa (MD)-specific NOS1 knockout mice (NKCC2-Cre-NOS1 flox/flox) using a new inducible NKCC2-Cre line crossed with NOS1 flox mice. AKI was induced by 18-min bilateral renal pedicle clamping at 37°C, followed by 48-h reperfusion. Kidney injury was assessed by measuring GFR, plasma creatinine, histology, cytokines, apoptosis, fibrotic factors, and proteomics. Complete NOS1 deletion in MD cells was confirmed through NKCC2/NOS1 immunofluorescence. MD NOS1 deletion enhanced the TGF response, which was further amplified following AKI compared with control (Cre −/−). Following AKI, compared with controls (Cre −/−), NOS1 knockouts showed a significantly lower GFR (236 ± 66 to 24 ± 22 μl/min) and higher plasma creatinine levels, alongside more severe tubular damage evidenced by H&E staining. Cytokine array analysis showed chemokines such as MCP-1 and CXCL1 and macrophage marker CD68 were significantly increased; Western blot analysis showed cleaved caspase-3 levels were significantly increased, indicating enhanced apoptosis. Additionally, fibrosis markers TIMP-1, collagen-3, and α-SMA were significantly up-regulated at both mRNA and protein levels. We further observed increased hypoxia marker hypoxia-inducible factor-1α in MD-specific NOS1 knockout mice (Cre +/−). Global label-free proteomic profiling with targeted validation identified genotype-dependent responses involving haptoglobin, Tacstd2, and Cyp20a1, linking NOS1 deficiency to exaggerated inflammatory, fibrotic, and metabolic pathways. These findings highlight a novel role of MD NOS1 and TGF in AKI pathophysiology, suggesting NOS1 targeting as a therapeutic strategy. Haptoglobin was identified as a downstream plasma signal of NOS1-dependent AKI responses, indicating potential translational value.

Abstract Medulloblastoma (MB) is one of the most prevalent malignant brain tumors in children, with tremendous cognitive and neuroendocrine disability among survivors. Group 3 (G3) MBs have poor overall survival at < 50%, higher frequency of metastasis, and no targeted therapies. Amplification of MYC and activation of TGFβ signaling are frequent in G3MB. Remarkably, some tumors have no reported mutations, suggesting roles for epigenetic mechanisms in driving disease. We have generated novel humanized models for G3MB by transducing neuroepithelial stem cells (NESC) derived from human induced pluripotent stem (iPSC) cells with TGFβ effectors alone and/or in combination with MYC, prioritizing combinations observed in patients. We determined that both MYC and TGFβ effectors drove tumor formation in vivo with the combination driving more aggressive tumors and higher frequency of metastasis. NESC-derived tumors clustered with human G3/G4MB, indicating our models recapitulated human disease. To decipher mechanisms of resistance, we integrated CUT&RUN for MYC genomic localization and histone PTMs with RNA-sequencing and discovered MYC-bound neural developmental genes repressed in MYC and TGFβR1-driven lines. Further interrogation identified JARID1B, a MYC binding partner, as a regulator of many of these repressed neural genes. We postulate that deregulation of MYC and context-specific targeting to the chromatin template culminates in transcriptional alterations that promote aggressive G3MB. To further investigating therapeutic vulnerabilities, we have performed a in vivo whole genome CRISPRi screen to reveal important drivers of malignancy, one of the first of it’s kind in brain tumors. We are functionally validating key candidate sgRNAs that were differentially significant in primary tumors and may also have key roles in driving metastasis. Excitingly, many sgRNAs identified from the screen were chromatin modifiers and may be important co-factors of MYC-mediated regulation on the epigenome. Collectively, our studies provide a critical framework for understanding mechanisms of resistance and the epigenetic landscape of MYC- and TGFβ-driven MB.

Abstract The recent FDA approval of the first T-cell receptor–engineered (TCR) T-cell cancer therapy has solidified the treatment as a viable therapeutic strategy. However, only a fraction of patients who received this treatment achieved substantial and long-lasting responses, highlighting the need to understand the molecular underpinnings of these responses and develop more effective strategies to improve this therapy. Previous research has demonstrated that the activation of myeloid differentiation primary response 88 (MyD88) signaling in tumor-specific T cells functions as a robust costimulatory signaling pathway that promotes effective antitumor T-cell responses. In this study, we developed a strategy for improving TCR T-cell therapies by creating a synthetic TCR in which the intracellular domain of CD3ζ and a modified MyD88 are appended to the β-chain of a tumor-reactive TCR. The β:CD3ζ:MyD88 TCR activated MyD88 signaling in a tumor antigen/TCR-specific manner, and β:CD3ζ:MyD88 TCR T cells exhibited enhanced functionality and a reduced propensity to become exhausted. Furthermore, MyD88 signaling promoted T-cell persistence and expansion in vitro. In vivo, tumor-infiltrating β:CD3ζ:MyD88 TCR T cells skewed the immunosuppressive tumor microenvironment toward a less immunosuppressive state. Finally, β:CD3ζ:MyD88 TCR T cells substantially delayed tumor growth kinetics in a melanoma model. These findings introduce an approach for improving TCR-dependent T-cell responses by directly appending signaling domains to the full-length TCR and exemplify the utility of activating MyD88 signaling in tumor-specific T cells. Significance: A chimeric β:CD3ζ:MyD88 TCR reduces exhaustion and improves antitumor T-cell responses, overcoming the limited efficacy of current TCR-engineered T-cell cancer therapies.

Background: Healing of the tendon-bone interface (TBI) after rotator cuff injury is limited, often leading to scar-mediated repair. Decellularized tendon fibrocartilage–bone composite (dTFBC) and bone marrow mesenchymal stem cell sheets (BMSCS) improve repair in preclinical models, but full scaffold encapsulation with mechanical preconditioning remains unexplored. Purpose: To evaluate TBI regeneration using mechanically preconditioned, BMSCS-encapsulated dTFBC scaffolds in a rabbit model. Study Design: Controlled laboratory study. Methods: A total of 48 male New Zealand White rabbits were randomized into 4 groups (n = 12 each): (1) standard repair (control); (2) repair with dTFBC; (3) repair with dTFBC-BMSCS; and (4) repair with mechanically preconditioned dTFBC-BMSCS (mdTFBC-BMSCS). Healing at 12 weeks was assessed via gross observation, histomorphological and immunohistochemical analyses, and biomechanical testing. Results: The mdTFBC-BMSCS group demonstrated a higher ultimate failure load (mean, 203.9 ± 65.6 N) than both the control (118 ± 37.4 N; P = .003) and dTFBC groups (127 ± 44.1 N; P = .008), with no significant difference between the 2 BMSCS-treated groups. Histological analysis revealed enhanced fibrocartilage formation, improved collagen fiber organization, and reduced inflammation infiltration at the TBI in the mdTFBC-BMSCS group. Immunohistochemical analysis showed greater collagen type 2 alpha 1 chain-, interleukin 10-, and arginase 1-positive areas in the mdTFBC-BMSCS group than in the control and dTFBC groups. Conclusion: Mechanically preconditioned, fully BMSCS-encapsulated dTFBC scaffolds promoted TBI regeneration, with enhanced cellular integration, fibrocartilage formation, and favorable biomechanical performance. Clinical Relevance: This biomimetic scaffold strategy may enhance biological healing and reduce the risk of retear after rotator cuff repair.

Abstract Motivation Intratumor heterogeneity arises from ongoing somatic evolution and complicates cancer diagnosis, prognosis, and treatment. Reconstructing evolutionary dynamics typically requires spatiotemporal samples, which are often unavailable in clinical settings. Computational approaches that can infer tumor evolutionary history from single-timepoint bulk sequencing data remain limited. Results We present estimating evolutionary events through single-timepoint sequencing (TEATIME), a novel computational framework that models tumors as mixtures of two competing cell populations: an ancestral clone with baseline fitness and a derived subclone with elevated fitness. Using cross-sectional bulk sequencing data, TEATIME estimates mutation rates, timing of subclone emergence, relative fitness, and number of generations of growth. To quantify intratumor fitness asymmetries, we introduce a novel metric—fitness diversity—which captures the imbalance between competing cell populations and serves as a measure of functional intratumor heterogeneity. Applying TEATIME to 33 tumor types from The Cancer Genome Atlas, we revealed divergent as well as convergent evolutionary patterns. Notably, we found that immune-hot microenvironments constraint subclonal expansion and limit fitness diversity. Moreover, we detected temporal dependencies in mutation acquisition, where early driver mutations in ancestral clones epistatically shape the fitness landscape, predisposing specific subclones to selective advantages. These findings underscore the importance of intratumor competition and tumor-microenvironment interactions in shaping evolutionary trajectories, driving intratumor heterogeneity. Lastly, we demonstrate that TEATIME-derived evolutionary parameters and fitness diversity offer novel prognostic insights across multiple cancer types. Availability and implementation R implementation of TEATIME is available on GitHub (https://github.com/liliulab/TEATIME) and Zenodo (https://zenodo.org/records/17422174).

Abstract Platinum-based chemotherapy remains a cornerstone of treatment for triple-negative breast cancer (TNBC), yet the molecular determinants governing platinum response remain poorly defined. By leveraging the randomized Phase II INFORM trial, which compared neoadjuvant cisplatin to anthracycline-based therapy in BRCA1/2 -mutant breast cancer—we identified miR-362-3p as a specific regulator of cisplatin sensitivity. Higher plasma miR-362-3p expression was exclusively associated with favorable clinical outcome in the cisplatin arm, with no association observed in the AC arm, decoupling platinum-specific vulnerability from general chemotherapy response. We used gain- and loss-of-function TNBC models to establish that miR-362-3p functions as a potent sensitizer to cisplatin in vitro and in vivo . Integrated TCGA analysis and experimental validation identified BCLAF1, a key regulator of DNA damage response, as a direct repression target of miR-362-3p. We uncovered a novel role for the miR-362-3p/ BCLAF1 axis in overcoming platinum resistance in TNBC.

Liver transplantation has emerged as a curative treatment option for selected patients with unresectable hepatic malignancies beyond hepatocellular carcinoma, marking a paradigm shift in transplant oncology. For colorectal cancer liver metastases (CRLM), prospective trials have demonstrated that highly selected patients achieve 5-year OS rates of 60–83%, with the Oslo score identifying optimal candidates for transplantation. Perihilar cholangiocarcinoma (pCCA) has been successfully treated using strict patient selection criteria combined with neoadjuvant therapy, achieving 5-year OS rates of 50–68%, though emerging data suggests chemotherapy-based approaches may be preferable to radiation in selected cases. Intrahepatic cholangiocarcinoma (iCCA), previously considered a contraindication to transplantation, can now achieve excellent long-term outcomes (79.5% 5-year OS) in patients demonstrating sustained response to neoadjuvant chemotherapy and radioembolization, with metabolic tumor volume < 70 cm3 serving as an objective prognostic marker. Across these three emerging indications, successful outcomes depend on strict patient selection based on tumor biology, intensive multimodal neoadjuvant therapy, multidisciplinary evaluation in high-volume centers, and careful observation during treatment to exclude patients with aggressive disease. This evolution in transplant practice offers curative intent therapy to patients that previously only had palliative therapeutic options, fundamentally transforming hepatobiliary and oncologic surgery.