Modeling Studies Research Articles

Origins of synergy in multilipid lubrication

Lipid bilayers, ubiquitous in living systems, form lubricious boundary layers in aqueous media, with broad relevance for biolubrication, especially in mechanically stressed environments such as articular cartilage in joints, as well as for modifying material interfacial properties. Model studies have revealed efficient lubricity by single-component lipid bilayers; synovial joints, however (e.g. hips and knees), comprise over a hundred different lipids, raising the question of whether this is natural redundancy or whether it confers any lubrication benefits. Here, we examine lubrication by progressively more complex mixtures of lipids representative of those in joints, using a surface forces balance at physiologically relevant salt concentrations and pressures. We find that different combinations of such lipids differ very significantly in the robustness of the bilayers to hemifusion under physiological loads (when lubrication breaks down), indicating a clear lubrication synergy afforded by multiple lipid types in the bilayers. Insight into the origins of this synergy is provided by detailed molecular dynamics simulations of potential profiles for the formation of stalks, the essential precursors of hemifusion, between bilayers of the different lipid mixtures used in the experiments. These reveal how bilayer hemifusion-and thus lubrication breakdown-depends on the detailed lipid bilayer composition, through the corresponding separation into domains that are better able to resist stalk formation. Our results shed light on the role of lipid-type proliferation in biolubrication synergy, point to improved treatment modalities for common joint diseases such as osteoarthritis, and indicate how lipid-based interfacial modification in a materials context may be optimized.

Abstract 4122301: The Role of Hepatic CDS2 in Phosphatidylinositol Homeostasis and Lipid Metabolism

Background: Recent studies in both human genetics and mouse models have highlighted the significance of phosphatidylinositol (PI) in the progression of fatty liver disease (FLD). Despite this, the precise mechanisms underlying PI's role remain elusive. Aims: This study aimed to elucidate the involvement of PI in FLD by disrupting hepatic PI biosynthesis through modulation of CDP-diacylglycerol synthase 2 (CDS2) expression, the primary enzyme in PI biosynthesis (A). Methods: We generated liver-specific knockouts of CDS2 and SCAP (SREBP cleavage-activating protein) using adeno-associated virus (AAV) expressing sgRNA against each gene. Phospholipid species were analyzed and quantified by LC/MS. Results: CDS2 liver-specific knockout mice (B, C) exhibited a pronounced development of fatty liver, characterized by elevated triglyceride and cholesterol levels (C). Notably, liver PI levels were significantly reduced in CDS2 knockout mice (E), accompanied by dysregulated activation of sterol regulatory element-binding protein (SREBP) even during fasting conditions (F), leading to increased de novo lipogenesis. Intraperitoneal administration of exogenous PI effectively normalized SREBP cleavage (G), highlighting PI's critical role in SREBP regulation. Furthermore, simultaneous knockout of SCAP with CDS2 restored the normal liver phenotype, implicating SREBP activation as a central mechanism underlying fatty liver development in CDS2 knockout mice (H, I). Conclusion: Deletion of CDS2 in the liver reduced PI levels, subsequently inducing significant fatty liver due to dysregulated SREBP activation. This study underscores the importance of CDS2 in maintaining PI homeostasis, which in turn regulates SREBP activity and lipid metabolism. Our findings provide valuable insights into the pathogenesis of metabolic disorders and offer potential therapeutic strategies for targeting FLD.

IEPA, a novel radiation countermeasure, alleviates acute radiation syndrome in rodents

Repurposing therapeutic agents with existing clinical data is a common strategy for developing radiation countermeasures. IEPA (imidazolyl ethanamide pentandioic acid) is an orally bioavailable small molecule pseudopeptide with myeloprotective properties, a good clinical safety profile, and stable chemical characteristics facilitating stockpiling. Here, we evaluated IEPA’s radiomitigative efficacy in the hematopoietic subsyndrome of acute radiation syndrome (H-ARS) using total-body irradiation (TBI) models in C57BL/6J mice and WAG/RijCmcr rats, applying various posology schemes and introducing syringe feeding of the IEPA formulation in the pudding. Additionally, we assessed IEPA in the delayed effects of acute radiation exposure (DEARE) model after partial-body irradiation (PBI) in WAG/RijCmcr rats. Endpoints included survival, body weight, hematology, and pulmonary parameters, depending on the model. Results from mouse and rat TBI models demonstrated survival improvements with repeated IEPA dosing at 10 mg/kg, with the largest benefits observed in the bi-daily (BID) treatment over the 30-day ARS phase in female rats. Survival across PBI-DEARE subsyndromes was comparable between IEPA and vehicle groups, though IEPA improved pulmonary parameters in female rats during the lung-DEARE phase. Sex-related differences in response to irradiation and IEPA were noted, with females showing a survival advantage. IEPA treatment is compatible with Neulasta® (Pegfilgrastim; PEG-G-CSF); adequately powered studies are needed to confirm the trend toward improved survival over standard care alone. IEPA is a promising development candidate as a medical countermeasure against the effects of acute radiation syndrome. Further confirmatory studies in small and large animal models should validate the robustness and translatability of preliminary rodent data on IEPA’s radiomitigative efficacy.

Stability analysis study for the time-fractional Galilei invariant advection-diffusion model of distributive order using an efficient hybrid approach

Abstract In this manuscript, a new model of the time-fractional Galilei-invariant advection-diffusion model of distributed order is studied. An efficient hybrid numerical approach with high accuracy is used to estimate this equation. The finite difference numerical method is used to approximate the fractional operator in terms of the time variable and to approximate the integral term of distributed order, the Gaussian–Legendre integration is applied. To obtain a fully discrete numerical approach, we used a spectral element numerical approach, in which Legendre polynomials are used as the basis function. For the proposed numerical approach, the error and stability analysis are studied. For the efficiency of the numerical approach, some numerical examples are presented with graphs and tables.

The competency of the novel through-the-scope suture device for gastric mucosal defects: In vivo study in a porcine model (with video).

Endoscopic closures of mucosal defects following endoscopic resection can be challenging and time-consuming. The novel through-the-scope suture device has demonstrated acceptable closure times, but its learning curve is still unknown. This study aims to evaluate the number of cases required to achieve competency in this device. Two endoscopists participated; a novice with less than 400 experiences in upper gastrointestinal endoscopy and an expert with over 500 experiences in endoscopic submucosal dissection. Neither endoscopist had previous exposure to the device. In four porcine models, 24 gastric mucosal defects, each 2-4 cm in diameter, were created by endoscopic mucosal resection with ligation. Each endoscopist performed endoscopic closure for 12 mucosal defects with a single through-the-scope suture device per lesion. The primary endpoint was the number of cases needed to reach competency, defined as achieving a procedure time below the average closure time reported in the literature. Secondary endpoints included procedure time, complete closure success rates, and incidence of adverse events. The mean defect size was 2.9 (±0.2) cm. Competency was achieved after six cases in the expert and seven cases in the novice. The median closure time was 9.0 (interquartile range [IQR]: 6.0-11.0) min for the expert and 8.0 (IQR: 6.2-9.7) min for the novice (p = 0.862). Complete closure success rates were 75.0% (n = 9) for the expert and 83.3% (n = 10) for the novice. No adverse events were reported. A small number of cases were required for both expert and novice endoscopists to reach competency in the novel through-the-scope suture device.

A systematic review on feature extraction methods and deep learning models for detection of cancerous lung nodules at an early stage -The Recent trends and challenges.

Lung cancer is one of the most common life-threatening worldwide cancers affecting both the male and female populations. The appearance of nodules in the scan image is an early indication of the development of cancer cells in the lung. The Low Dose Computed Tomography screening technique is used for the early detection of cancer nodules. Therefore, with more Computed Tomography (CT) lung profiles, an automated lung nodule analysis system can be utilized through image processing techniques and neural network algorithms. A CT image of the lung consists of many elements such as blood vessels, ribs, nodules, sternum, bronchi, and nodules. These nodules can be both benign and malignant, where the latter leads to lung cancer. Detecting them at an earlier stage can increase life expectancy by up to 5 to 10 years. To analyze only the nodules from the profile, respected features are calculated using image processing techniques. Based on the review, textural features were promising ones in medical image analysis and for solving computer vision problems. The significance of extracting the hidden features (textural) enables the higher performance of deep learning algorithms (DL) predominantly in medical imaging, which has resulted in improvement in accuracy in recent years. Earlier detection of cancerous lung nodules is possible through the combination of multi-featured extraction and classification techniques using image data. In this paper, we discussed the overview of lung cancer along with publicly available datasets for research purposes. The primary objective of the paper is to provide the importance of textural features when combined with different deep-learning models. It gives insights into their advantages, disadvantages, and limitations regarding possible research gaps. The paper compared the recent studies of deep learning models with and without feature extraction and concluded that DL models that include feature extraction were better than the others.

The Lymphatic Vasculature in Lung Homeostasis and Disease.

The lymphatic vasculature maintains lung homeostasis via fluid drainage in the form of lymph and by facilitating immune surveillance and leukocyte trafficking to the draining lymph nodes. Previous studies in both humans and animal models have demonstrated an important role for lymphatics in lung function from the neonatal period through adulthood. In addition, changes in the lymphatic vasculature have been observed in many respiratory diseases, and there is emerging evidence of a causative role for lymphatic dysfunction in the initiation and progression of lung pathology. Despite advances in the field, there are still many unanswered questions, and a more comprehensive understanding of the mechanisms by which the lymphatics affect lung homeostasis and the response to lung injury is needed. In this review, we discuss our current knowledge of the structure, function, and role of the lymphatics in the lung and how these vessels are involved in respiratory disease.

The comparative role of physical system processes in Hudson Strait ice stream cycling: a comprehensive model-based test of Heinrich event hypotheses

Abstract. Despite their recognized significance on global climate and extensive research efforts, the mechanism(s) driving Heinrich events remain(s) a subject of debate. Here, we use the 3D thermomechanically coupled glacial systems model (GSM) to examine the Hudson Strait ice stream surge cycling and the role of three factors previously hypothesized to play a critical role in Heinrich events: ice shelves, glacial isostatic adjustment, and sub-surface ocean temperature forcings. In contrast to all previous modeling studies examining HEs, the GSM uses a transient last glacial cycle climate forcing, global viscoelastic glacial isostatic adjustment model, and sub-glacial hydrology model. The results presented here are based on a high-variance sub-ensemble retrieved from North American history matching for the last glacial cycle. Over our comparatively wide sampling of the potential parameter space (52 ensemble parameters for climate forcing and process uncertainties), we find two modes of Hudson Strait ice streaming: classic binge–purge versus near-continuous ice streaming with occasional shutdowns and subsequent surge onset overshoot. Our model results indicate that large ice shelves covering the Labrador Sea during the last glacial cycle only occur when extreme calving restrictions are applied. The otherwise minor ice shelves provide insignificant buttressing for the Hudson Strait ice stream. While sub-surface ocean temperature forcing leads to minor differences regarding surge characteristics, glacial isostatic adjustment does have a significant impact. Given input uncertainties, the strongest controls on ice stream surge cycling are the poorly constrained deep geothermal heat flux under Hudson Bay and Hudson Strait and the basal drag law. Decreasing the geothermal heat flux within available constraints and/or using a Coulomb sliding law instead of a Weertman-type power law leads to a shift from the near-continuous streaming mode to the binge–purge mode.

Abstract 4122650: 1-year comparison of quadruple therapy sequencing strategies for heart failure with reduced ejection fraction using an individual-based state-transition microsimulation model

Introduction: Guidelines recommend quadruple therapy (angiotensin receptor blocker-neprilysin inhibitor [ARNI]), beta-blocker, mineralocorticoid receptor antagonist (MRA), and sodium-glucose co-transporter 2 inhibitor [SGLT2I]) as the cornerstone of heart failure (HF) with reduced ejection fraction (HFrEF) management. Yet, guidelines do not propose a specific order of initiation and titration (or “sequencing strategy”) of these agents, due to the absence of trial evidence. Aims: To model the 1-year efficacy and harms of proposed HFrEF quadruple therapy sequencing strategies using a microsimulation model. Methods: We conducted an individual-based state-transition microsimulation modeling study to compare the 1-year cumulative incidence of death, total HF hospitalization, and adverse events with 6 different HFrEF medication sequencing strategies (emulating 2 different traditional strategies, 2 two-drug combinations, a "cluster" strategy, and four-drug "simultaneous" strategy), each with two versions (weekly or biweekly medication adjustments), applied to treatment-naïve outpatients with HFrEF. We modeled death as an incidence at 1 year, and total HF hospitalization (first and recurrent events) and adverse events (bradycardia, hyperkalemia, hypotension, and renal impairment) as incidence rates per 100 patient-years. Results: At 1 year, an estimated 15.5% died without treatment compared to 6.9% with the traditional sequence adjusted biweekly, and 5.2-6.3% with other sequencing strategies. Similarly, the HF hospitalization rate decreased from 32.8 per 100 patient-years with no treatment to 11.1 per 100 patient-years traditional sequencing adjusted biweekly, and 6.9-9 per 100 patient-years with other strategies. The incidence rates of medication-related adverse events per 100 patient-years were: hypotension (5.8-6.9), renal impairment (4.6-6.0), bradycardia (2.9-3.2), and hyperkalemia (approximately 0.5). Conclusions: For treatment-naïve outpatients with HFrEF, pharmacotherapy sequencing strategies that started 2 to 4 medications on the first visit reduced the risk of death and hospitalization at 1 year compared to a traditional sequencing strategy. Weekly medication adjustments did not outperform biweekly adjustments when >=2 medications were started on the initial visit. These findings can inform clinicians and policymakers in developing HFrEF medication optimization programs with sequencing strategy protocols that fit the local practical context.

Projecting atmospheric N2O rise until the end of the 21st century: an Earth System Model study

Abstract Nitrous Oxide (N2O) is a potent greenhouse gas with a centennial-scale lifetime that contributes significantly to global warming. It is emitted from natural and anthropogenic sources. In nature, N2O is released mainly from nitrification and denitrification from the ocean and terrestrial systems. The use of agricultural fertilizers has significantly increased the emission of N2O in the past century. Here we present, to our knowledge, the first coupled ocean and terrestrial N2O modules within an Earth System Model. The coupled modules were used to simulate the six Shared Socioeconomic Pathways (SSPs) scenarios with available nitrogen fertilizer inputs. Our results are compared to projections of atmospheric N2O concentrations used for SSPs scenario experiments. Additionally, an extra set of simulations were prescribed with emulated N2O concentrations available as input in Shared Socioeconomic Pathways scenarios. We report four main drivers for terrestrial N2O uncertainties: atmospheric temperature, agricultural fertilizer input, soil denitrification and agricultural model dynamics. We project an atmospheric N2O concentration range from 401 to 418 ppb in six SSPs simulations with a robust lack of sensitivity to equilibrium climate sensitivity. We found a large difference between our low emission scenarios N2O concentrations by 2100 compared to the concentration provided for SSPs experiments. This divergence is likely explained by strong mitigation assumptions that were not accounted for in this study, which would require a substantial decrease of agricultural N2O emissions. The coupled model and the simulations prescribed with N2O concentrations showed a difference between −0.02 and 0.09 ∘C by 2100. Our model simulation shows a lack of sensitivity to climate mitigation efforts projecting similar N2O concentration in low and high mitigation scenarios, that could indicate the need of further development of agricultural model dynamics. Further improvements in Earth system models should focus on the impact of oxygen decline on N2O dynamics in the ocean and the representation of anaerobic soils and agricultural dynamics on land, including mitigation methods on nitrogen fertilizers.

Gastric Cancer Risk among Immigrants and Socioeconomic Groups in the Netherlands.

Identification of groups at a high-risk of gastric cancer (GC) could facilitate targeted screening in countries with a low GC incidence. Our aim was to identify such high-risk groups, based on individual-level population data on migration history and socioeconomic status (SES) in the Netherlands. In this retrospective cohort study, patient data from the Netherlands cancer registry were linked to demographic data of Statistics Netherlands in the period 2010-2022. GC incidence rates in the 14 largest immigrant populations were compared to those born in the Netherlands. Odds ratios (ORs) were computed per birthplace and controlled for age, sex and SES. Additionally, we investigated GC risk among second-generation immigrants and by SES. Immigrant populations at a significantly higher GC risk compared to the general population were identified. Specifically, foreign-born first-generation immigrants from Bosnia-Herzegovina (OR: 2.42), Turkey (OR: 2.22) and China (OR: 1.92) showed elevated risk. While low SES increased the odds of developing GC, first-generation immigrants remained at higher risk even after controlling for SES. Second-generation immigrants did not have a significantly higher risk of developing GC. Certain first-generation immigrants remain at an elevated risk for GC despite migration to a low-risk region. Identification of these high-risk groups should be used to facilitate targeted GC prevention. Potential benefits of targeted Helicobacter pylori test-and-treat policy in immigrant populations should be explored in clinical and modelling studies. Primary care physicians should be cognizant of high-risk groups, facilitating the early-detection of cancer within these populations.

EXTH-65. EXPLORING ANTIHISTAMINES TO TREAT GLIOBLASTOMA

Abstract BACKGROUND Glioblastoma (GBM) is an aggressive and lethal primary malignant brain tumor with a 5-year survival of 6.8%. Interestingly, people with allergies, atopy, or asthma are less likely to develop GBM. A recent study recognized that high histamine receptor 1 (HRH1) expression is inversely related to overall and progression-free survival. METHODS We used a bioinformatics tool, iLINCS, which, after analyzing 99 GBM and 38 healthy samples, identified 36 drugs that can reverse GBM signatures. Based on the concordance score and blood-brain barrier permeability, we selected brompheniramine (Brom), a first-generation HRH1 antagonist, as a potential candidate. HRH1 expression analysis was done on human and mouse GBM cell lines by immunoblotting. The effect of Brom alone or in combination with temozolomide (TMZ) was investigated on proliferation, DNA damage and apoptosis in human (U118 and U251) and three syngeneic (EGFRvIII, p16-/- & GFAP Cre, PTEN+/-, p53R172H+/-, EGFRvIII & GFAP Cre, PTEN-/-, p53R172H-/- & GFAP Cre) cell lines. GBM orthograft mouse models were used to test the efficacy of combination therapy. RESULTS HRH1 is highly expressed in human and syngeneic GBM cells. This expression is further increased in TMZ-resistant cells. Interestingly, the addition of histamine, induced TMZ resistance in GBM cells. TMZ with Brom decreases proliferation in mouse and human GBM cells, and Brom is non-toxic to non-transformed cells. Combination treatment increases DNA damage and decreases the DNA repair mechanism, possibly by downregulating the expression of O6methylguanine-DNA methyltransferase (MGMT). In the GBM orthograft mouse model, the combination therapy reduced tumor volume and significantly increased survival compared to single-agent treatment. CONCLUSIONS Brom is non-toxic; Brom, in combination with TMZ, enhanced the anti-tumor efficacy of TMZ both in in vitro and in vivo GBM models. Further studies in spontaneous mouse models are planned.

NCMP-13. EXPLORING THE PATHOPHYSIOLOGY OF HYDROCEPHALUS IN CHOROID PLEXUS PAPILLOMA

Abstract BACKGROUND Choroid plexus papilloma (CPP) is a benign intraventricular lesion associated with hydrocephalus and ventricular outflow obstruction. However, the molecular mechanism by which cerebrospinal fluid (CSF) is produced by choroid plexus (CP), or by which CSF production is altered in the setting of CPP to cause hydrocephalus, is unknown. METHODS A PRISMA systematic literature review was conducted to identify gene targets associated with CSF production. Primary tissue samples of CP and CPP from the same patient were obtained, and expression of target genes was assessed using immunohistochemistry and quantified using QuPath software H-scoring. Single-nucleus sequencing of both CP and CPP was also completed, and differential expression of identified target genes was evaluated by calculating log fold change. RESULTS Systematic literature review yielded 25 studies in animal models and 18 unique gene targets. 16 targets were expressed in primary CP and CPP tissue samples upon immunohistochemistry staining. 11 of 18 targets revealed significant differential expression between CP and CPP on single-nucleus sequencing. Genes with notable expression increases in CPP included ion transporters NKCC1 (Na-K-Cl cotransporter) and TRPV4 (non-selective cation channel), as well as carbonic anhydrase II. CONCLUSIONS We present evidence that choroid plexus papilloma has altered expression of genes previously implicated in CSF production. Upregulation of membrane transporters and cytoplasmic enzymes involved in Na+, K+, Cl-, and HCO3- transport may provide a mechanistic explanation for the development of hydrocephalus in CPP. Pharmacologic inhibition of CSF production may offer a route for non-surgical management of CPP, as well as other pathologies causing hydrocephalus.

Thymoquinone-Incorporated CollaGee Biomatrix: A Promising Approach for Full-Thickness Wound Healing

Wound infection is the leading cause of delayed wound healing. Despite ongoing research, the ideal treatment for full-thickness skin wounds is yet to be achieved. Skin tissue engineering provides an alternative treatment, with the potential for skin regeneration. Background/Objectives: Previously, we characterized a collagen–gelatin–elastin (CollaGee) acellular skin substitute and evaluated its cytocompatibility. The assessments revealed good physicochemical properties and cytocompatibility with human dermal fibroblasts (HDF). This study aimed to incorporate thymoquinone (TQ) as the antibacterial agent into CollaGee biomatrices and evaluate their cytocompatibility in vitro. Methods: Briefly, dose–response and antibacterial studies were conducted to confirm the antimicrobial activity and identify the suitable concentration for incorporation; 0.05 and 0.1 mg/mL concentrations were selected. Then, the cytocompatibility was evaluated quantitatively and qualitatively. Results: Cytocompatibility analysis revealed no toxicity towards HDFs, with 81.5 + 0.7% cell attachment and 99.27 + 1.6% cell viability. Specifically, the 0.05 mg/mL TQ concentration presented better viability, but the differences were not significant. Immunocytochemistry staining revealed the presence of collagen I, vinculin, and alpha smooth muscle actin within the three-dimensional biomatrices. Conclusions: These results suggest that TQ-incorporated CollaGee biomatrices are a promising candidate for enhancing the main key player, HDF, to efficiently regenerate the dermal layer in full-thickness skin wound healing. Further investigations are needed for future efficiency studies in animal models.

Artificial Ex Utero Systems to Treat Severe Periviable Fetal Growth Restriction—A Possible Future Indication?

Fetal growth restriction, or intrauterine growth restriction, is a common gestational condition characterized by reduced intrauterine growth. However, severe periviable fetal growth restriction is still associated with elevated perinatal mortality and morbidity. The current literature advises delivery once it is deemed that fetal compromise is evident. As uteroplacental insufficiency is the most common etiology of this condition, we hypothesize that the use of artificial ex utero systems to provide adequate nutrition and recreate the uterine environment may be a viable treatment option in this situation, even with the possibility of treating severe fetal growth restriction and prevent sequelae. There are promising experimental studies in sheep models investigating the artificial ex utero system for potential prenatal conditions, but future additional investigation is needed before translating to clinical trials in humans.

NCOG-26. THERAPEUTIC POTENTIAL OF FECAL MICROBIOME TRANSPLANT TO IMPROVE COGNITIVE DYSFUNCTION INDUCED BY CRANIAL IRRADIATION IN MICE

Abstract Radiation therapy (RT) is a crucial treatment for brain tumors, but radiation-induced cognitive dysfunction (RICD) affects 50-90% of patients, significantly impacting their quality of life. Evidence suggests that gut microbiome dysfunction may contribute to progressive cognitive dysfunction (CD). Prior studies in aging and stroke models show that fecal microbiome transplants (FMT) from healthy hosts can promote recovery and improve cognition. To investigate the link between RICD and the gut microbiome, we subjected mice to Sham/9Gy/15Gy cranial irradiation, followed by cognitive tests using the Y-maze and Novel Object Recognition Test (NORT) at various time points. Both 9Gy and 15Gy irradiation resulted in significant cognitive dysfunction, as indicated by altered performance in both tests at 7 and 30 days post-irradiation. Fecal samples were collected before irradiation and at 10 and 30 days post-RT. Microbial DNA was extracted, and the 16S rRNA gene was sequenced and analyzed using the bioinformatics visualization toolkit, ATIMA. Significant gut dysbiosis was observed in both 9Gy and 15Gy irradiated mice compared to pre-irradiation samples, with the 15Gy group showing more pronounced and consistent changes in fecal microbiome diversity, particularly at 30 days post-RT. We hypothesized that FMT from healthy hosts (non-radiated mice) could prevent or ameliorate RICD by modulating microbial, metabolomic, and immunologic profiles. To test this, a separate cohort of mice received 15Gy cranial irradiation and FMT via oral gavage. After a 20-day post-irradiation period, cognitive and gut permeability tests were conducted. The FMT group exhibited significantly improved gut permeability and cognitive performance compared to controls. Our findings suggest that gut dysbiosis plays a crucial role in RICD and that FMT may be a potential strategy to mitigate RICD and improve the quality of life in brain tumor patients undergoing cranial RT.

Molecular modeling and cytotoxic activity studies of oxirane-2-carboxylate derivatives

In this study, five 3-aryloxirane-2-carboxylate derivatives were prepared, and the antiproliferative activities of molecules were screened in lung and colon cancer cell lines. The results showed that molecules had antiproliferative activity on cancerous cells with IC50 values under 100 µM. Furthermore, all of the molecules were found to have a much higher cytotoxic effect than cisplatin in colon cancer cells. The interactions of the relatively active compounds to the crucial enzyme in cancer cell proliferation, cyclin-dependent kinase 1 (CDK1), were investigated using molecular docking. The stability of the resulting CDK1-compound complexes procured from the docking was also assessed through molecular dynamics (MD) simulations. Then, the binding affinity of compounds 2-3a and 2-3c to the target enzyme was computed by MMPBSA. The molecular docking study demonstrated that the two most active compounds could bind to the enzyme. The binding potential of 2-3a is anticipated to be higher as it had one more conventional hydrogen bond and a slightly lower binding energy than compound 2-3c. The MD simulation study exhibited that the two compounds formed a stable complex with the enzyme. On the other hand, the MMPBSA energy computation implicated a slightly higher binding affinity for compound 2-3c toward the enzyme. Furthermore, electrical and frontier molecular orbital analysis of all of the tested compounds was conducted by density functional theory (DFT) studies. Compound 2-3a is anticipated to be the most chemically stable as it gave the highest energy gap value in the DFT analysis.

Unveiling the impact of hypodermis on gene expression for advancing bioprinted full-thickness 3D skin models.

3D skin models have been explored as an alternative method to the use of animals in research and development. Usually, human skin equivalents comprise only epidermis or epidermis/dermis layers. Herein, we leverage 3D bioprinting technology to fabricate a full-thickness human skin equivalent with hypodermis (HSEH). The collagen hydrogel-based structure provides a mimetic environment for skin cells to adhere, proliferate and differentiate. The effective incorporation of the hypodermis layer is evidenced by scanning electron microscopy, immunofluorescence, and hematoxylin and eosin staining. The transcriptome results underscore the pivotal role of the hypodermis in orchestrating the genetic expression of a multitude of genes vital for skin functionality, including hydration, development and differentiation. Accordingly, we evidence the paramount significance of full-thickness human skin equivalents with hypodermis layer to provide an accurate in vitro platform for disease modeling and toxicology studies.

TMOD-02. PATIENT-DERIVED GLIOBLASTOMA ORGANOIDS AS REAL-TIME AVATARS FOR ASSESSING RESPONSES TO CLINICAL CAR-T CELL THERAPY

Abstract Patient-derived tumor organoids have been increasingly leveraged for disease modeling and preclinical studies, but rarely in real-time to aid with the interpretation of patient treatment responses in the clinical setting. Whether tumor organoids can be applied to mirror clinical activity in patients and even to predict responses for personalized medicine remains uncertain. We recently demonstrated promising early efficacy signals in a first-in-human, phase 1 study of dual-targeting chimeric antigen receptor T cells (EGFR-IL13Rα2 CAR-T cells) in patients with recurrent glioblastoma (clinical trial identifier: NCT05168423). Determination of meaningful clinical efficacy, in particular for CAR-T cell therapy, may take months to manifest. Given this challenge, real-time analysis of patient-derived glioblastoma organoids (GBOs) could help to provide early assessment of clinical efficacy and guide patient management. We analyzed six sets of GBOs generated on the same timeline as the production of patients’ CAR-T cell products. GBOs demonstrated the presence and retention of both targeted tumor-associated antigens EGFR and IL13Rα2 by immunohistochemistry. These GBOs were then treated with the same autologous CAR-T cell products received by patients in our phase 1 study in parallel with patient treatment. CAR-T cell treatment led to target antigen reduction assessed by immunohistochemistry and flow cytometry. Furthermore, we confirmed cytolysis of tumor cells in GBOs by cleaved caspase-3 immunostaining and by co-culture in the Axion Maestro Cellular Impedance platform. Importantly, the degree of cytolysis ex vivo significantly correlated with CAR-T cell engraftment detected in patients’ cerebrospinal fluid (CSF) for all six patients. Furthermore, cytotoxic activity of CAR-T cells as measured by TNFα, IL-2, and IFNγ release kinetics in GBOs mirrored cytokine levels in patient CSF samples over time. Our findings highlight a unique trial design and suggest GBOs as a valuable platform for real-time assessment of CAR-T cell bioactivity and for insights into immunotherapy efficacy.

CTNI-17. A PHASE 2 STUDY OF SAFETY AND EFFICACY OF CONCURRENT ACT001 AND RADIATION TREATMENT FOLLOWED BY ACT001 MAINTENANCE THERAPY IN NEWLY DIAGNOSED PEDIATRIC PATIENTS WITH DIFFUSE INTRINSIC PONTINE GLIOMA (DIPG)

Abstract BACKGROUND ACT001, an oral parthenolide derivative targeting NF-κB and STAT3 pathways, has shown activity in preclinical DIPG model and dose-finding study in patients with diffuse midline glioma. We further evaluated safety and activity of ACT001 in newly diagnosed DIPG patients and presented the interim data from exploratory stage of this phase 2 study. METHODS Eligible patients ≥ 5 and ≤ 15 years old were treated with concurrent ACT001 and standard radiation followed by ACT001 single agent treatment in this single arm, open label, multicenter phase 2 study. Tumor lesions were evaluated at baseline, 4 weeks and then every 8 weeks after the end of radiation therapy per RAPNO criteria with ORR as primary endpoint. Interim data analysis was performed when data from approximately 20 efficacy evaluable patients became available during the exploratory stage of this study. RESULTS Among 30 patients enrolled since Sept, 2023, 27 took at least one dose of ACT001 by April 30th, 2024, the data cutoff date (with exception for May 15th as the MRI cutoff date). While 3 patients were quickly taken off study due to a disease progression or consent withdrawal, 17 out of 27 patients finished at least one post-radiation MRI exam whereas MRI results are pending for 7 other patients by this interim analysis. Median age was 8 years old and male to female patient ratio is 17:10. The median LPS score is 70.0. Among 17 efficacy evaluable subjects, 8 patients exhibited partial response (6 confirmed) including one with a deep tumor reduction (-91.7%) noted three months after end of radiation. Among 9 other evaluable patients, 5 and 4 exhibited ongoing stable disease and progressive disease respectively. Subject 05001 was considered PD despite confirmed objective response for the target lesion upon development of new lesions. Two patients withdrew consent after finishing first post-radiation MRI scans despite initial tumor burden reduction which were both close to PR criteria. Patients tolerated concurrent ACT001 and radiation well. In total, 289 TEAE and 184 TRAE events were reported in 23 and 22 patients respectively. There were two ACT001-related grade 3 or 4 adverse events including one grade 4 hemorrhagic tumor necrosis (a SUSAR event and the only ACT001 related SAE) likely due to a therapeutic effect of ACT001 and one clinically insignificant grade 3 decreased lymphocyte count. Most common TRAE were manageable grade 1 or 2 events such as weight loss (15/184), vomiting (71/184), decreased lymphocyte count (13/184) and abdominal bloating (7/184). No study discontinuation occurred due to ACT001 or radiation related TRAEs. Conclusion. Concurrent ACT001 and radiation treatment was well tolerated. Preliminary evidence of anti-tumor activity was shown in about 50% efficacy evaluable DIPG patients. It is worthwhile to explore ACT001 and temozolomide combination in future study based on safety and efficacy signal from DIPG and recurrent GBM studies. The confirmatory stage of this study is in planning to further evaluate the anti-tumor efficacy signal of this NF-κB and STAT3 dual inhibitor.