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Background: Programmed Cell Death 4 (PDCD4) is a tumor suppressor known for promoting apoptosis and inhibiting growth and protein translation in cancer cells. However, the role of PDCD4 in the heart remains elusive. This study explores PDCD4's regulation and function in the heart through genetic manipulation. Methods: Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), neonatal mouse cardiomyocytes, and transgenic mice with constitutive cardiomyocyte-specific PDCD4 overexpression were used in this study. In vitro, PDCD4 expression was manipulated by plasmid-based overexpression or siRNA-mediated knockdown, and confirmed by Western blot. Subcellular localization of PDCD4 was assessed by immunofluorescence staining. Apoptosis was evaluated using cleaved-PARP immunoblotting and TUNEL staining. Cardiac function in mice was assessed by echocardiography. Results: In hiPSC-CMs and isolated neonatal cardiomyocytes, expression of PDCD4 is predominantly found in the nucleus, suggesting a possible role in nuclear signaling or gene regulation. Treatment of hiPSC-CMs with 1 μM doxorubicin (DOX) for 3 days significantly reduced PDCD4 expression. Functionally, PDCD4 overexpression attenuated DOX-induced apoptosis, as evidenced by decreased cleaved-PARP levels and fewer TUNEL-positive cells, whereas PDCD4 knockdown increased cell death, indicating a protective role under chemotherapeutic stress. PDCD4 expression decreased in mouse hearts during postnatal development. Transgenic mice with cardiomyocyte-specific PDCD4 overexpression showed normal heart weight, size, and function, without induced apoptosis under baseline conditions. We are currently investigating the potential cardioprotection of PDCD4 transgene against DOX induced acute and chronic cardiotoxicities. Conclusion: PDCD4 has a pro-apoptotic function in cancer cells but demonstrates an anti-apoptotic role in cardiomyocytes during chemotherapeutic stress in vitro. These observations indicate a context-dependent role for PDCD4 in cardioprotection, presenting it as a potential therapeutic target for reducing cardiotoxicity during cancer treatment.

Introduction: Designer receptors exclusively activated by designer drugs (DREADDs) are a robust chemogenetic tool for the interrogation of cellular electrical activity. Particularly, hM4Di activates the Gi signaling pathway, and can induce cellular hyperpolarization, leading to decreased electrical activity. Our aim is to engineer human induced pluripotent stem cell-derived cardiomyocytes (hiSPC-CMs) with controllable electromechanical properties to elucidate the role of transplanted hiPSC-CMs in cardiac regeneration. We hypothesize that activating hM4Di in transgenic hiSPC-CMs will inhibit their electrical activity. Methods: We developed a new hiPSC line expressing DREADD using the PiggyBac system (PB). The PB transposon included the hM4Di gene under the cTnT promoter, with mCherry and puromycin resistance genes as transfection markers ( Fig 1A ). After establishing the line, we differentiated these hiPSCs into DREADD-expressing cardiomyocytes (hiPSC-CM M4Di ). We activated hM4Di using clozapine N-oxide (CNO) and determined the optimal concentration through a concentration swipe. Optical mapping was used to analyze the electrical activity of hiPSC-CM M4Di . Results: After transfection, we observed the expression of mCherry in hiPSCs ( Fig 1B ). Additionally, we confirmed that these cells retained their pluripotency by evaluating the stemness markers Sox2 and Nanog ( Fig 1C ). Then, we performed directed cardiac differentiation. The cells showed spontaneous beating after day 8 of differentiation. We determined that the optimal concentration for hiPSC-CM M4Di inhibition was 200µM CNO, based on concentration swipe. Furthermore, our optical mapping data showed that spontaneous beating rate was decreased 30 minutes after adding CNO and completely stopped at 60 minutes. The spontaneous beating recovered after CNO was removed. CNO did not affect the electrical behavior of wild type cells (Fig 1D) . Conclusions: We developed a transgenic hiPSC line expressing DREADD. The produced hiPSC-CM M4Di responded positively to the CNO ligand, allowing inhibition of their electromechanical activity. This cell line holds potential for investigating the electrophysiology of grafted hiPSC-CMs, and for application as disease model in vitro.

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) possess significant therapeutic potential for myocardial regeneration. However, clinical application remains constrained due to the immature phenotype of these cells, which impacts their engraftment as well as their electrical and mechanical integration post-transplantation into the injured heart. In particular, proper alignment of transplanted hiPSC-CMs is essential for synchronous contraction and efficient electromechanical coupling with native tissue. To address this critical clinical challenge, we engineered a tissue patch incorporating aligned electrospun nanofibers designed to enhance hiPSC-CM alignment and promote their structural maturation. Poly(caprolactone) (PCL) nanofibers were fabricated by electrospinning a 10% w/v solution in 1,1,1,3,3,3-hexafluoro-2-propanol at a flow rate of 0.5 mL/h. A voltage of 14 kV was applied to the spinneret and 3kV to the collector, positioned 13 cm away, with additional electrodes to induce fiber alignment. Scanning electron microscopy and ImageJ analysis confirmed fiber diameter and orientation. hiPSC-CMs (1 x 10 6 cells) were seeded onto fiber scaffolds with varied diameters (1.0, 1.5, and 2.0 μm) and densities (low: 20%, moderate: 30%, high: 40%). Among these, 1.5 ± 0.2 μm diameter fibers with a density of 40 ± 3% provided the most effective topographical cues for promoting cell elongation and alignment. Immunofluorescence staining demonstrated that hiPSC-CMs cultured on aligned fibers exhibited enhanced cytoskeletal organization along the fiber axis. Morphological assessment over time showed progressive alignment by day 3. Importantly, hiPSC-CMs cultured on aligned fibers demonstrated stronger and more synchronized contractile activity compared to those cultured on flat glass surfaces. Together, these findings suggest that our aligned nanofiber-based cardiac patch promotes the structural and functional maturation of hiPSC-CMs, highlighting their potential as an advanced platform for improving cardiac cell therapy outcomes.

Background Immune-related adverse events (irAEs) remain largely unpredictable, potentially affecting multiple organ systems and occurring at almost any point during and even occasionally after immune checkpoint inhibitor (ICI) treatment. To identify populations at risk for these immune-mediated toxicities, we analyzed genetic characteristics and immune markers associated with clinically significant irAEs. Methods We carried out a genome-wide association study on 373 white patients receiving ICI treatment. We identified single nucleotide polymorphisms associated with irAEs. Blood cytokine profiling and peripheral blood mononuclear cell RNA sequencing were performed at pretreatment baseline and 6–8 weeks after ICI initiation. Findings were validated in two external cohorts. Results We identified genetic haplotypes in VWA8 (Von Willebrand Factor A Domain Containing 8) , OSBPL6 (Oxysterol Binding Protein Like 6), and ADAMTS9-AS2 (ADAM Metallopeptidase With Thrombospondin Type 1 Motif 9 Antisense RNA 2) associated with grade ≥2 irAEs. Patients carrying risk haplotypes for one or more genes exhibited significantly greater rates of grade ≥2 (OR 3.02; 95% CI 1.83 to 5.02; p<0.001), grade ≥3 (OR 3.59; 95% CI 1.93 to 6.64; p<0.001), and multiple type irAE (OR 2.60; 95% CI 1.53 to 4.39; p<0.001). Serum CCL3 levels were significantly elevated in individuals carrying risk haplotypes (p=0.03). Gene expression analysis demonstrated activated autoimmune and inflammatory pathways in the genetic risk group. Conclusions Novel polymorphisms in VWA8, OSBPL6, and ADAMTS9-AS2 may impact immune pathways, promote inflammation, potentiate autoimmune phenotypes, and convey risk of irAE in ICI-treated patients.

Abstract Background Carbon ion radiotherapy (CIRT), characterized by its Bragg peak and a reduced lateral scattering compared to proton radiotherapy (PT), offers excellent dose conformity in radiation treatment. Meanwhile, compared to PT, CIRT causes more complex and severe DNA damage in tumor cells, which results in a higher relative biological effectiveness (RBE), making it particularly advantageous in treating radioresistant and hypoxia tissues than conventional radiotherapy. However, CIRT's high RBE and the nuclear fragmentation dose tail outside the target presents challenges in sparing organ at risk (OARs). Combining PT and CIRT offers a potential hybrid modality that leverages the biological effectiveness of carbon ions while minimizing normal tissue toxicity with high biological damage. Purpose Despite the potential of combining PT and CIRT, balancing their respective advantages while mitigating disadvantages remains a significant challenge. This study aims to develop an optimized treatment approach that automatically adjusts the relative contributions of protons and carbon ions, improving target dose conformity while minimizing biological impact on OARs. Methods We propose a biological optimization framework for multi‐modality combining PT and CIRT (CCIPRT). The biological dose is modeled as the product of the physical dose and RBE. Through iterative Jacobian‐based linearization, the biological dose of carbon ion is expressed in a linear model, enabling the formulation of a linear least‐square objective. The biological dose of proton is formulated as a linear model using the physical dose and dose‐averaged linear energy transfer (LET). The joint optimization problem is then solved using iterative convex relaxation and the alternating direction method of multipliers. For comparison, single‐modality PT and CIRT were also implemented. Results When the target dose of CCIPRT is prescribed in terms of the physical dose, compared to PT, CCIPRT increased the mean biological dose in the target by 37.7%, 29.6%, and 31.1% for brain, lung, and abdomen, respectively; compared to CIRT, CCIPRT reduced the biological dose in CTV1cm (ring surrounding CTV with 1 cm width) by 47.2%, 32.3%, and 40.4% for brain, lung, and abdomen, respectively. When the target dose of CCIPRT is prescribed in terms of the biological dose, compared to PT, CCIPRT achieved higher conformity index (CCIPRT: 0.96 and 0.97; PT: 0.93 and 0.96 for brain and liver cases, respectively) and reduced the dose in CTV1cm by 9.5% and 7.0% for brain and liver cases, respectively; compared to CIRT, CCIPRT enhanced healthy tissue sparing, reducing the dose to the body by 7.5% and 9.2% for brain and liver cases, respectively. Conclusions A novel multi‐modality CCIPRT treatment planning is developed with demonstrated superior performance over single‐modality PT or CIRT, with enhanced biological effectiveness and dose conformity compared to PT and reduced OAR dose compared to CIRT.

Background Myxomatous mitral valve disease (MMVD) is a degenerative disorder marked by excess tissue fibrosis and matrix remodeling, leading to leaflet prolapse. While recent studies linked transforming growth factor beta (TGF-β) activation to MMVD development and progression, upstream regulators of this and other modulatory/causal pathways remain largely unexplored. Objectives In this study, we utilized high-throughput sequencing to conduct unbiased analyses of mRNA and microRNA (miRNA) levels in myxomatous and healthy mitral valve tissues, aiming to uncover novel molecular mechanisms involved in MMVD. Methods We defined differentially expressed mRNAs and miRNAs transcripts displaying a fold-change > 1.5 and P < .05. Pathway analysis was performed using Ingenuity Pathway Analysis and DAVID, with key findings validated via qRT-PCR. A total of 2378 transcripts were differentially expressed between myxomatous and normal valves. Established pathways, including TGF-β signaling, were confirmed as major contributors to MMVD. Additionally, Random Forests with Boruta Feature Selection identified transcripts with a 95% likelihood of importance, and subsequent pathway analysis on this subset of genes revealed unique signaling pathways. Results Most notably, circadian rhythm disruption emerged as a novel, highly ranked pathway in MMVD. Key miRNAs, such as miR-1, miR-133a, and miR-217 were highlighted as highly relevant, with miRNA–mRNA interactions displaying distinct molecular signatures predictive of MMVD. Conclusions Collectively, this study represents the first comprehensive analysis of both miRNA and mRNA expression in MMVD, revealing both established and novel disease-associated pathways. The discovery of circadian rhythm disturbances and new regulatory miRNAs suggests promising directions for further research and potential therapeutic targets for nonsurgical treatment strategies in patients with MMVD.

Immune checkpoint inhibitors (ICIs) are an important class of cancer treatment. Endocrine immune-related adverse events (E-irAEs) account for a significant proportion of irAEs in ICI-treated patients. Diagnosing E-irAEs accurately and timely can be challenging in the absence of clear categorization and standardization across oncology, endocrinology and other specialties. While existing guidelines provide some broad directions to diagnosis and management, they lack clarity on irAE-specific symptom evaluation and work-up, as well as assessment of severity. These limitations can then impact triage, time-sensitive management and care escalation to specialists such as oncoendocrinologists. The objective of this study was to develop consensus-based statements on disease definitions for E-irAEs. A core working group of endocrinologists with expertise in the oncoendocrinology field drafted a survey with statements outlining the general approach to E-irAEs, disease definition and management approach of six specific diagnoses: ir-thyroiditis thyrotoxic phase, ir-thyroiditis hypothyroidism, ir-Graves’ disease, ir-hypophysitis, ir-adrenalitis and ir-type 1 diabetes mellitus. Severity grading tables were drafted for three disease categories—“thyroid”, “pituitary and adrenal”, and “diabetes mellitus”. A two-round modified Delphi process, using the RAND/University of California Los Angeles (RAND/UCLA) Appropriateness Method, was employed. In this process, a 25-member voting panel consisting of endocrinologists, oncologists and other specialists and healthcare providers with experience in management of ICI-treated patients and irAEs was recruited. The panel rated anonymously on usability, accuracy, appropriateness or agreement of 41 items on a 9-point scale in Survey 1, after which a meeting was convened. Statements were modified based on voting results from Survey 1 and Meeting 1, and the process was repeated in Survey 2 and Meeting 2. At the end of this process, consensus was achieved for all statements. Our study findings address the gap in standardized nomenclature, clinical, laboratory and radiological evaluations, and management principles of E-irAEs. With consensus achieved from a panel of experts from a variety of disciplines, we anticipate that the statements can form the basis for standardization of the diagnostic process and improvement of patient care.

Abstract Objective To evaluate the effect of erenumab treatment beyond monthly migraine days in patients with high‐frequency episodic migraine who did not respond to at least one previous migraine preventive treatment. Background Reduction in monthly migraine days has been the efficacy standard for migraine preventive treatments; however, it does not fully capture the holistic benefit of the therapy. Erenumab, a monoclonal antibody targeting the calcitonin gene–related peptide pathway, has demonstrated reduction in monthly migraine days and improvement in function in patients with episodic and chronic migraine. Methods In this phase 4, interventional, double‐blind, randomized, placebo‐controlled, multicenter, global study, treatment with erenumab was assessed over 4 months in adults with high‐frequency episodic migraine. The study was conducted at 61 sites located across North America and Europe between September 2020 and October 2023. Patients with ≥1 qualifying oral triptan‐treated migraine attack at baseline were randomized to receive erenumab 140 mg or placebo subcutaneously once monthly. The primary endpoint was change from baseline in mean monthly hours of at least moderate headache pain intensity over months 1, 2, and 3; secondary endpoints included change from baseline in mean monthly function, mean monthly duration of at least moderate pain intensity in migraine attacks, and mean monthly peak migraine pain intensity. Safety outcomes were also assessed. Results Of 512 randomized patients, 510 received erenumab 140 mg ( n = 254) or placebo ( n = 256) once monthly. Demographics and baseline characteristics were balanced between the two treatment arms. Erenumab 140 mg was superior to placebo in reducing duration of moderate or severe headache pain intensity over months 1, 2, and 3 (least squares mean [95% confidence interval {CI}] difference, −7.95 [−11.45, −4.46]; p < 0.001). Compared with placebo, erenumab significantly reduced migraine functional impact as assessed by the four domains of the Migraine Functional Impact Questionnaire, with a least squares mean (95% CI) difference of −7.36 (−10.80, −3.92) for physical functioning, −7.10 (−10.34, −3.87) for usual activities, −6.82 (−10.37, −3.27) for social functioning, and − 7.05 (−10.76, −3.34) for emotional functioning ( p < 0.001 for all domains). Significant reductions with erenumab compared with placebo were also observed in duration of at least moderate pain intensity in residual or break‐through migraine attacks (least squares mean [95% CI] difference, −1.07 [−1.92, −0.22]; p = 0.013) and peak migraine pain intensity (−0.48 [−0.85, −0.11]; p = 0.011). Incidence of grade 3 adverse events was 1.6% with erenumab and 1.2% with placebo; no grade 4 or fatal adverse events were reported in either treatment arm. Conclusion Findings from the EMBRACE study demonstrated that treatment with erenumab in patients with high‐frequency episodic migraine can provide positive therapeutic effects on ictal burden and pain, with residual migraine attacks tending to be shorter and less painful, with less overall impact.

Background: Doxorubicin (DOX) is an effective chemotherapy but limited by severe cardiotoxicity. Chemokine receptors CXCR4 and CXCR7 are involved in regulating cardiac survival, inflammation, and fibrosis, yet their specific roles in DOX-induced cardiotoxicity (DICT) remain unclear. Objective: We investigated the cardioprotective effects of TC14012, a dual-target CXCR4 antagonist and CXCR7 agonist, against DICT. Methods: Male C57BL/6J mice received chronic or acute DOX administration with twice-weekly TC14012 treatment. Cardiac function was evaluated by echocardiography. Markers of cardiac fibrosis and inflammation were assessed. RNA-seq analysis was performed to explore associated molecular pathways. Key pathways were validated in cardiac cells and bone marrow-derived mast cells. Results: TC14012 significantly improved cardiac function, indicated by preservation of ejection fraction and fractional shortening, and increased survival rates optimally at 5 mg/kg, which were accompanied with reductions in cardiac collagen deposition and infiltration of macrophages and neutrophils. RNA-seq revealed that TC14012 protecting against DICT was associated with a remarkable stimulation of signals involving in cardiac contraction and energy reserve metabolism processes, particularly glycogen and glucan metabolism that are crucial for meeting the cardiac energy demand in response to DOX induction. These signals could be further enriched into AMPK signalling pathway and validated by enhancement of cardiac AMPK phosphorylation both in vivo and in vitro . Meanwhile, TC14012’s cardioprotective effects were accompanied by a reduction in signals involving in cardiac mast cell activation and degranulation, which could be enriched into Rap1 signalling pathway and validated by TC14012 inhibiting mast cell activation and Rap1-GTP activity in vitro . Importantly, TC14012 did not compromise DOX’s antitumor efficacy in EL-4 lymphoma-bearing mice. Conclusions: TC14012 may prevent DICT by activating CXCR7-AMPK signalling to reprogram cardiomyocyte metabolism and antagonizing CXCR4-Rap1 signalling to blunt mast cell-mediated sentinel effects without compromising the anticancer efficacy DOX.