Highly sensitive mapping of in vitro type II topoisomerase DNA cleavage sites with SHAN-seq.

Type II topoisomerases (topos) are a ubiquitous and essential class of enzymes that form transient enzyme-bound double-stranded breaks on DNA called cleavage complexes. The location and frequency of these cleavage complexes on DNA is important for cellular function, genomic stability and a number of clinically important anticancer and antibacterial drugs, e.g. quinolones. We developed a simple high-accuracy end-sequencing (SHAN-seq) method to sensitively map type II topo cleavage complexes on DNA in vitro. Using SHAN-seq, we detected Escherichia coli gyrase and topoisomerase IV cleavage complexes at hundreds of sites on supercoiled pBR322 DNA, approximately one site every ten bp, with frequencies that varied by two-to-three orders of magnitude. These sites included previously identified sites and 20-50-fold more new sites. We show that the location and frequency of cleavage complexes at these sites are enzyme-specific and vary substantially in the presence of the quinolone, ciprofloxacin, but not with DNA supercoil chirality, i.e. negative versus positive supercoiling. SHAN-seq's exquisite sensitivity provides an unprecedented single-nucleotide resolution view of the distribution of gyrase and topoisomerase IV cleavage complexes on DNA. Moreover, the discovery that these enzymes can cleave DNA at orders of magnitude more sites than the relatively few previously known sites resolves the apparent paradox of how these enzymes resolve topological problems throughout the genome.

Deacetylation of GLUD1 maintains the survival of lung adenocarcinoma cells under glucose starvation by inhibiting autophagic cell death.

Enhanced glutamine catabolism is one of the main metabolic features of cancer, providing energy and intermediate metabolites for cancer progression. However, the functions of glutamine catabolism in cancer under nutrient deprivation need to be further clarified. Here, we discovered that deacetylation of glutamate dehydrogenase 1 (GLUD1), one of the key enzymes in glutamine catabolism, maintains the survival of lung adenocarcinoma (LUAD) cells under glucose starvation by inhibiting autophagic cell death. We found that glucose starvation increased GLUD1 activity by reducing its acetylation on Lys84 and promoted its active hexamer formation. Besides, deacetylation of GLUD1 induced its cytoplasmic localization, where GLUD1 was ubiquitinated in K63-linkage by TRIM21, leading to the binding of GLUD1 with cytoplasmic glutaminase KGA. These two effects enhanced glutamine metabolism both in mitochondria and cytoplasm, increased the production of alpha-ketoglutarate (α-KG). Meanwhile, cytoplasmic GLUD1 also interacted with p62 and prevented its acetylation, leading to the inhibition of p62 body formation. All these effects blocked autophagic cell death of LUAD cells under glucose starvation. Taken together, our results reveal a novel function of GLUD1 under glucose deprivation in LUAD cells and provide new insights into the functions of glutamine catabolism during cancer progression.

A Fixed-Time Proximal Gradient Neurodynamic Network With Time-Varying Coefficients for Composite Optimization Problems and Sparse Optimization Problems With Log-Sum Function.

This article presents a novel proximal gradient neurodynamic network (PGNN) for solving composite optimization problems (COPs). The proposed PGNN with time-varying coefficients can be flexibly chosen to accelerate the network convergence. Based on PGNN and sliding mode control technique, the proposed time-varying fixed-time proximal gradient neurodynamic network (TVFxPGNN) has fixed-time stability and a settling time independent of the initial value. It is further shown that fixed-time convergence can be achieved by relaxing the strict convexity condition via the Polyak-Lojasiewicz condition. In addition, the proposed TVFxPGNN is being applied to solve the sparse optimization problems with the log-sum function. Furthermore, the field-programmable gate array (FPGA) circuit framework for time-varying fixed-time PGNN is implemented, and the practicality of the proposed FPGA circuit is verified through an example simulation in Vivado 2019.1. Simulation and signal recovery experimental results demonstrate the effectiveness and superiority of the proposed PGNN.

RBM5 induces motor neuron apoptosis in hSOD1G93A-related amyotrophic lateral sclerosis by inhibiting Rac1/AKT pathways.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder distinguished by gradual depletion of motor neurons. RNA binding motif protein 5 (RBM5), an abundantly expressed RNA-binding protein, plays a critical role in the process of cellular death. However, little is known about the role of RBM5 in the pathogenesis of ALS. Here, we found that RBM5 was upregulated in ALS hSOD1G93A-NSC34 cell models and hSOD1G93A mice due to a reduction of miR-141-5p. The upregulation of RBM5 increased the apoptosis of motor neurons by inhibiting Rac1-mediated neuroprotection. In contrast, genetic knockdown of RBM5 rescued motor neurons from hSOD1G93A-induced degeneration by activating Rac1 signaling. The neuroprotective effect of RBM5-knockdown was significantly inhibited by the Rac1 inhibitor, NSC23766. These findings suggest that RBM5 could potentially serve as a therapeutic target in ALS by activating the Rac1 signalling.

Advances in Machine Learning for Wearable Sensors.

Recent years have witnessed tremendous advances in machine learning techniques for wearable sensors and bioelectronics, which play an essential role in real-time sensing data analysis to provide clinical-grade information for personalized healthcare. To this end, supervised learning and unsupervised learning algorithms have emerged as powerful tools, allowing for the detection of complex patterns and relationships in large, high-dimensional data sets. In this Review, we aim to delineate the latest advancements in machine learning for wearable sensors, focusing on key developments in algorithmic techniques, applications, and the challenges intrinsic to this evolving landscape. Additionally, we highlight the potential of machine-learning approaches to enhance the accuracy, reliability, and interpretability of wearable sensor data and discuss the opportunities and limitations of this emerging field. Ultimately, our work aims to provide a roadmap for future research endeavors in this exciting and rapidly evolving area.

Liver regeneration after injury: Mechanisms, cellular interactions and therapeutic innovations.

The liver possesses a distinctive capacity for regeneration within the human body. Under normal circumstances, liver cells replicate themselves to maintain liver function. Compensatory replication of healthy hepatocytes is sufficient for the regeneration after acute liver injuries. In the late stage of chronic liver damage, a large number of hepatocytes die and hepatocyte replication is blocked. Liver regeneration has more complex mechanisms, such as the transdifferentiation between cell types or hepatic progenitor cells mediated. Dysregulation of liver regeneration causes severe chronic liver disease. Gaining a more comprehensive understanding of liver regeneration mechanisms would facilitate the advancement of efficient therapeutic approaches. This review provides an overview of the signalling pathways linked to different aspects of liver regeneration in various liver diseases. Moreover, new knowledge on cellular interactions during the regenerative process is also presented. Finally, this paper explores the potential applications of new technologies, such as nanotechnology, stem cell transplantation and organoids, in liver regeneration after injury, offering fresh perspectives on treating liver disease.

Ethnokinesiology: towards a neuromechanical understanding of cultural differences in movement.

Each individual's movements are sculpted by constant interactions between sensorimotor and sociocultural factors. A theoretical framework grounded in motor control mechanisms articulating how sociocultural and biological signals converge to shape movement is currently missing. Here, we propose a framework for the emerging field of ethnokinesiology aiming to provide a conceptual space and vocabulary to help bring together researchers at this intersection. We offer a first-level schema for generating and testing hypotheses about cultural differences in movement to bridge gaps between the rich observations of cross-cultural movement variations and neurophysiological and biomechanical accounts of movement. We explicitly dissociate two interacting feedback loops that determine culturally relevant movement: one governing sensorimotor tasks regulated by neural signals internal to the body, the other governing ecological tasks generated through actions in the environment producing ecological consequences. A key idea is the emergence of individual-specific and culturally influenced motor concepts in the nervous system, low-dimensional functional mappings between sensorimotor and ecological task spaces. Motor accents arise from perceived differences in motor concept topologies across cultural contexts. We apply the framework to three examples: speech, gait and grasp. Finally, we discuss how ethnokinesiological studies may inform personalized motor skill training and rehabilitation, and challenges moving forward.This article is part of the theme issue 'Minds in movement: embodied cognition in the age of artificial intelligence'.

Disturbed glucose homeostasis and its increased allostatic load in response to individual, joint and fluctuating air pollutants exposure: Evidence from a longitudinal study in prediabetes.

We investigated the effect of individual, joint and fluctuating exposure to air pollution (PM2.5, BC, NO3-, NH4+, OM, SO42-, PM10, NO2, SO2, O3) on glucose metabolisms among prediabetes, and simultaneously explored the modifying effect of lifestyle. We conducted a longitudinal study among prediabetes during 2018-2022. Exposure windows within 60-days moving averages and their variabilities were calculated. FBG, insulin, HOMA-IR, HOMA-B, triglyceride glucose index (TyG), glucose insulin ratio (GI) and allostatic load of glucose homeostasis system (AL-GHS) was included. Linear mixed-effects model and BKMR were adopted to investigate the individual and overall effects, respectively. We also explored the preventive role of lifestyle. Individual air pollutant was associated with increased FBG, insulin, HOMA-IR, HOMA-B, TyG, and decreased GI. People with FBG ≥6.1 mmol/L were more susceptible. Air pollutants mixture were only associated with increased HOMA-B, and constituents have the highest group-PIP. Air pollutants variation also exert harmful effect. We observed similar diabetic effect on AL-GHS. Finally, the diabetic effect of air pollutants disappeared if participants adopt a favorable lifestyle. Our findings highlighted the importance of comprehensively assessing multiple air pollutants and their variations, focusing on metabolic health status in the early prevention of T2D, and adopting healthy lifestyle to mitigate such harmful effect.

Radix Isatidis polysaccharide (RIP) alleviates QX-genotype infectious bronchitis virus-induced interstitial nephritis through the Nrf2/NLRP3/Caspase-3 signaling pathway.

Interstitial nephritis is the primary cause of mortality in IBV-infected chickens. Our previous research has demonstrated that Radix Isatidis polysaccharide (RIP) could alleviate this form of interstitial nephritis. To explore the mechanism, SPF chickens and chicken embryonic kidney cells (CEKs) were pre-treated with RIP and subsequently infected with QX-genotype IBV strain. Kidneys were sampled for transcriptomic and metabolomic analyses, and the cecum contents were collected for 16S rRNA gene sequencing. Results showed that pre-treatment with RIP led to a 50 % morbidity reduction in infected-chickens, along with decreased tissue lesion and viral load in the kidneys. Multi-omics analysis indicated three possible pathways (including antioxidant, anti-inflammatory and anti-apoptosis) which associated with RIP's efficacy against interstitial nephritis. Following further validation both in vivo and in vitro, the results showed that pre-treatment with RIP could activate the antioxidant transcription factor Nrf2, stimulate antioxidant enzyme expression, and consequently inhibit oxidative stress. Pre-treatment with RIP could also significantly reduce the expression of NLRP3 inflammasome and apoptosis-associated proteins (including Bax, Caspase-3, and Caspase-9). Additionally, RIP was also observed to promote the growth of beneficial bacteria in the intestine. Overall, pretreatment with RIP can alleviate QX-genotype IBV-induced interstitial nephritis via the Nrf2/NLRP3/Caspase-3 signaling pathway. This study lays the groundwork for the potential use of RIP in controlling avian infectious bronchitis (IB).

Investigating the filtration performance and service life of vehicle cabin air filters in China.

To protect occupants in vehicle cabin environments from the health risks of high concentrations of particulate matter (PM), it is important to install vehicle cabin air filter (VCAF) to eliminate PM. In this study, we investigated the filtration performance of 22 VCAFs. Results showed that the minimum average filtration efficiency was 56.1 % for particles with a diameter of 0.1-0.3 µm, a pressure drop of 33.2-250 Pa at air velocity of 2.5 m/s, and the dust-holding capacity ranged from 5.8 to 19.4 g. In addition, as the filter area increased from 0.23 m2 to 0.50 m2, the filtration efficiency for particles with a diameter of 0.1-0.3 µm increased from 56.7 % to 77.5 %, the pressure drop decreased from 96.1 to 62.5 Pa, and the dust holding capacity increased 2.7 times. Furthermore, we compared the service life of VCAF from 31 major Chinese cities and found that the service life varied greatly from maximum of 1730 h for Haikou to minimum of 352 h for Shijiazhuang. Considering occupant health risks, Beijing requires that VCAFs have PM2.5 filtration efficiency at least 88.1 %, and Liaoning requires minimum of 97.5 %. Hence, choosing the appropriate VCAF based on the atmospheric environment of different cities deserves our attention.

Best practices in wound care for gastrointestinal stoma and colorectal cancer patients from a nursing perspective: A meta-analysis.

Colorectal cancer, a type of colon or bowel cancer, poses a major challenge in the treatment of colorectal lesions. Colorectal endoscopic mucosal resection (EMR) is a minimally invasive technique, but the risk of wound infections remains a significant concern. These infections can impede the healing process, affecting daily activities and patient satisfaction. To mitigate the risk of wound infections, various prophylactic measures have been explored, including medication, vaccines, lifestyle adjustments and hygiene practices. This study aims to investigate the prevention of wound infections through prophylactic measures in colorectal EMR. A comprehensive literature review was conducted to identify prophylactic measures that can prevent wound infections. A systematic literature search was conducted using both free words and search terms. The data extraction was performed after a comprehensive literature screening. The meta-analysis was performed using the metabin function of the meta library in R to evaluate the infection incidences in intervention and control groups. A total of 599 infection incidences were considered, with 267 in intervention and 332 in the control group. The results of meta analysis demonstrated significant reduction of wound incidences following the prophylactic measures (risk ratio [RR] = 0.77, 95% confidence interval [CI]: 0.6747; 0.9016, I2 = 78.5%, p < 0.01). The wound infection ratio analysis also exhibited an approximate 6.6% less infection rate in the intervention group, demonstrating significantly less wound infection following the implementation of prophylactic measures. This study highlights the crucial significance of prevention of wound infections by prophylactic measures in colorectal EMR.

The Proteomic Landscape of Monocytes in Response to Colorectal Cancer Cells.

Colorectal cancer (CRC) involves a complex interaction between tumor cells and immune cells, notably monocytes, leading to immunosuppression. This study explored these interactions using in vitro coculture systems of THP-1 cells and CRC cell lines, employing quantitative proteomics to analyze protein changes in monocytes. Multiple analytical methods were utilized to delineate the altered proteomic landscape, identify key proteins, and their associated functional pathways for comprehensive data analysis. Differentially expressed proteins (DEPs) were selected and validated by cross-referencing them with publicly available TCGA and GEO data sets to explore their potential clinical significance. Our analysis identified 161 up-regulated and 130 down-regulated DEPs. The enrichment results revealed impairments in adhesion and innate immune functions in monocytes, potentially facilitating cancer progression. The down-regulation of FN1, THSB1, and JUN may contribute to these impairments. Furthermore, the overexpression of ADAMTSL4, PRAM1, GPNMB, and NPC2 on monocytes was associated with unfavorable prognostic outcomes in CRC patients, suggesting potential biomarkers or therapeutic targets. This study illustrated the proteomic landscape of monocytes in response to CRC cells, providing clues for future investigations of the crosstalk between cancer cells and monocytes within the tumor microenvironment.

RemixFormer++: A Multi-modal Transformer Model for Precision Skin Tumor Differential Diagnosis with Memory-efficient Attention.

Diagnosing malignant skin tumors accurately at an early stage can be challenging due to ambiguous and even confusing visual characteristics displayed by various categories of skin tumors. To improve diagnosis precision, all available clinical data from multiple sources, particularly clinical images, dermoscopy images, and medical history, could be considered. Aligning with clinical practice, we propose a novel Transformer model, named Remix-Former++ that consists of a clinical image branch, a dermoscopy image branch, and a metadata branch. Given the unique characteristics inherent in clinical and dermoscopy images, specialized attention strategies are adopted for each type. Clinical images are processed through a top-down architecture, capturing both localized lesion details and global contextual information. Conversely, dermoscopy images undergo a bottom-up processing with two-level hierarchical encoders, designed to pinpoint fine-grained structural and textural features. A dedicated metadata branch seamlessly integrates non-visual information by encoding relevant patient data. Fusing features from three branches substantially boosts disease classification accuracy. RemixFormer++ demonstrates exceptional performance on four single-modality datasets (PAD-UFES-20, ISIC 2017/2018/2019). Compared with the previous best method using a public multi-modal Derm7pt dataset, we achieved an absolute 5.3% increase in averaged F1 and 1.2% in accuracy for the classification of five skin tumors. Furthermore, using a large-scale in-house dataset of 10,351 patients with the twelve most common skin tumors, our method obtained an overall classification accuracy of 92.6%. These promising results, on par or better with the performance of 191 dermatologists through a comprehensive reader study, evidently imply the potential clinical usability of our method.

Chloroplast and whole-genome sequencing shed light on the evolutionary history and phenotypic diversification of peanuts.

Cultivated peanut (Arachis hypogaea L.) is a widely grown oilseed crop worldwide; however, the events leading to its origin and diversification are not fully understood. Here by combining chloroplast and whole-genome sequence data from a large germplasm collection, we show that the two subspecies of A. hypogaea (hypogaea and fastigiata) likely arose from distinct allopolyploidization and domestication events. Peanut genetic clusters were then differentiated in relation to dissemination routes and breeding efforts. A combination of linkage mapping and genome-wide association studies allowed us to characterize genes and genomic regions related to main peanut morpho-agronomic traits, namely flowering pattern, inner tegument color, growth habit, pod/seed weight and oil content. Together, our findings shed light on the evolutionary history and phenotypic diversification of peanuts and might be of broad interest to plant breeders.

Correlation of Apo B/A1 ratio with hemodynamics and hearing impairment degree in elderly patients with sudden sensorineural hearing loss.

Objective: To investigate the correlation of apolipoprotein B/A1 (Apo B/A1) ratio with hemodynamics and degree of hearing impairment in elderly patients with sudden sensorineural hearing loss (SSNHL). Methods: A total of 82 elderly patients with SSNHL diagnosed and treated in our hospital from July 2019 to September 2022 were retrospectively selected as the research group. The patients were divided into the mild group (22 cases), the moderate group (45 cases), and the severe group (15 cases) according to the degree of hearing impairment. 82 elderly people who underwent physical examination in our hospital during the same period were selected as the control group. The ApoB/A1 ratio and hemodynamic [whole blood low-shear viscosity (LSV), whole blood high-shear viscosity (HSV) and plasma viscosity (PV)] were measured in the two groups. The correlation of ApoB/A1 ratio with hemodynamics and degree of hearing impairment was analyzed. The predictive value of ApoB/A1 ratio and hemodynamics for the severity of SSNHL in elderly patients was analyzed. Results: Compared with the control group, the ApoB/A1 ratio, and the levels of LSV, HSV and PV were higher in the research group (P < 0.001). The ApoB/A1 ratio and content of LSV, HSV and PV in the moderate group were significantly increased compared with these in the mild group (P < 0.05). Compared with the moderate group, the ApoB/A1 ratio and the levels of LSV, HSV and PV in the severe group were significantly increased (P < 0.05). Pearson correlation analysis showed that ApoB/A1 was positively correlated with LSV, HSV and PV (r = 0.303, 0.312, 0.228, P < 0.01). Logistic regression analysis showed that the ApoB/A1 ratio, LSV, HSV and PV levels were independent risk factors for the degree of hearing impairment in elderly patients with SSNHL (P < 0.05). The area under the curve (AUC) of ApoB/A1, LSV, HSV and PV for predicting the severity of SSNHL in elderly patients was 0.701, 0.817, 0.838, and 0.765, respectively. The AUC of combined prediction was 0.926, the sensitivity was 86.67 %, and the specificity was 90.06 %. The sensitivity and specificity of combined detection were higher than those of single detection. Conclusion: The contents of ApoB/A1, HSV, LSV and PV were significantly increased in elderly patients with SSNHL, and their levels are significantly related to the degree of hearing impairment. The combined detection has high value in evaluating the severity of the disease.

Super-Durable, Tough Shape-Memory Polymeric Materials Woven from Interlocking Rigid-Flexible Chains.

Developing advanced engineering polymers that combine high strength and toughness represents not only a necessary path to excellence but also a major technical challenge. Here for the first time a rigid-flexible interlocking polymer (RFIP) is reported featuring remarkable mechanical properties, consisting of flexible polyurethane (PU) and rigid polyimide (PI) chains cleverly woven together around the copper(I) ions center. By rationally weaving PI, PU chains, and copper(I) ions, RFIP exhibits ultra-high strength (twice that of unwoven polymers, 91.4 ± 3.3 MPa), toughness (448.0 ± 14.2 MJ m-3), fatigue resistance (recoverable after 10 000 cyclic stretches), and shape memory properties. Simulation results and characterization analysis together support the correlation between microstructure and macroscopic features, confirming the greater cohesive energy of the interwoven network and providing insights into strengthening toughening mechanisms. The essence of weaving on the atomic and molecular levels is fused to obtain brilliant and valuable mechanical properties, opening new perspectives in designing robust and stable polymers.

IL-32 regulates trophoblast invasion through miR-205-NFκB-MMP2/9 axis contributing to the pregnancy-induced hypertension.

Interleukin-32 is a species-specific cytokine that plays an important role in inflammation, cancer, and other diseases; however, its role in reproductive and pregnancy-related diseases remains unknown. This study aimed to investigate the role of interleukin-32 in reproductive and pregnancy-related diseases. Placental tissues from patients with pregnancy-induced hypertension, healthy pregnant women, and trophoblast lines were analysed. Interleukin-32 expression was quantified via polymerase chain reaction and immunohistochemistry, and functional assays were performed after interleukin-32 modulation. Interleukin-32 was identified only in placental mammals, such as Carnivora, Cetartiodactyla, Chiroptera, Dermoptera, Lagomorpha, Perissodactyla, and Primates via bioinformatics. Immunohistochemistry and polymerase chain reaction revealed that interleukin-32 was highly expressed in human placental villi, poorly expressed in decidua and endometrial tissues, and was not detected in mouse tissues. Second, interleukin-32 upregulates miR-205 expression by increasing DROSHA expression, and miR-205 promotes interleukin-32 expression by targeting its promoter region. Interleukin-32 and miR-205 significantly enhanced the invasion ability of HTR8/SVneo cells (a trophoblast cell line) and the tube formation ability of human umbilical vein endothelial cells. Through quantitative reverse transcription polymerase chain reaction and western blotting, the interleukin-32/miR-205 loop increased MMP2 and MMP9 expression in HTR-8/SVneo cells via the nuclear factor kappa B signalling pathway. Finally, using quantitative reverse transcription polymerase chain reaction, interleukin-32 and miR-205 expression levels were significantly lower in the placentas of patients with pregnancy-induced hypertension than in women with normal pregnancies. In conclusion, interleukin-32 regulates trophoblast invasion through the miR-205-nuclear factor kappa B-MMP2/9 pathway, which is involved in pregnancy-induced hypertension.

Correction: Bo et al. Atg5 Regulates Selective Autophagy of the Parental Macronucleus during Tetrahymena Sexual Reproduction. Cells 2021, 10, 3071.

In the original publication [...].

Single-cell RNA sequencing and cell-cell communication analysis reveal tumor microenvironment associated with chemotherapy responsiveness in ovarian cancer.

BACKGROUND: To investigate the impact of the tumor microenvironment (TME) on the responsiveness to chemotherapy in ovarian cancer (OV). METHODS: We integrated single cell RNA-seq datasets of OV containing chemo-response information, and characterize their clusters based on different TME sections. We focus on analyzing cell-cell communication to elaborate on the mechanisms by which different components of the TME directly influence the chemo-response of tumor cells. RESULTS: scRNA-seq datasets were annotated according to specific markers for different cell types. Differential analysis of malignant epithelial cells revealed that chemoresistance was associated with the TME. Notably, distinct TME components exhibited varying effects on chemoresistance. Enriched SPP1+ tumor-associated macrophages in chemo-resistant patients could promote chemoresistance through SPP1 binding to CD44 on tumor cells. Additionally, the overexpression of THBS2 in stromal cells could promote chemoresistance through binding with CD47 on tumor cells. In contrast, GZMA in the lymphocytes could downregulate the expression of PARD3 through direct interaction with PARD3, thereby attenuating chemoresistance in tumor cells. CONCLUSION: Our study indicates that the non-tumor cell components of the TME (e.g. SPP1+ TAMs, stromal cells and lymphocytes) can directly impact the chemo-response of OV and targeting the TME was potentially crucial in chemotherapy of OV.

Disrupting YAP1-mediated glutamine metabolism induces synthetic lethality alongside ODC1 inhibition in osteosarcoma.

PURPOSE: Osteosarcoma, a highly malignant primary bone tumor primarily affecting adolescents, frequently develops resistance to initial chemotherapy, leading to metastasis and limited treatment options. Our study aims to uncover novel therapeutic targets for metastatic and recurrent osteosarcoma. METHODS: In this study, we proved the potential of modulating the YAP1-regulated glutamine metabolic pathway to augment the response of OS to DFMO. We initially employed single-cell transcriptomic data to gauge the activation level of polyamine metabolism in MTAP-deleted OS patients. This was further substantiated by transcriptome sequencing data from recurrent and non-recurrent patient tissues, confirming the activation of polyamine metabolism in progressive OS. Through high-throughput drug screening, we pinpointed CIL56, a YAP1 inhibitor, as a promising candidate for a combined therapeutic strategy with DFMO. In vivo, we utilized PDX and CDX models to validate the therapeutic efficacy of this drug combination. In vitro, we conducted western blot analysis, qPCR analysis, immunofluorescence staining, and PuMA experiments to monitor alterations in molecular expression, distribution, and tumor metastasis capability. We employed CCK-8 and colony formation assays to assess the proliferative capacity of cells in the experimental group. We used flow cytometry and reactive oxygen probes to observe changes in ROS and glutamine metabolism within the cells. Finally, we applied RNA-seq in tandem with metabolomics to identify metabolic alterations in OS cells treated with a DFMO and CIL56 combination. This enabled us to intervene and validate the role of the YAP1-mediated glutamine metabolic pathway in DFMO resistance. RESULTS: Through single-cell RNA-seq data analysis, we pinpointed a subset of late-stage OS cells with significantly upregulated polyamine metabolism. This upregulation was further substantiated by transcriptomic profiling of recurrent and non-recurrent OS tissues. High-throughput drug screening revealed a promising combination strategy involving DFMO and CIL56. DFMO treatment curbs the phosphorylation of YAP1 protein in OS cells, promoting nuclear entry and initiating the YAP1-mediated glutamine metabolic pathway. This reduces intracellular ROS levels, countering DFMO's anticancer effect. The therapeutic efficacy of DFMO can be amplified both in vivo and in vitro by combining it with the YAP1 inhibitor CIL56 or the glutaminase inhibitor CB-839. This underscores the significant potential of targeting the YAP1-mediated glutamine metabolic pathway to enhance efficacy of DFMO. CONCLUSION: Our findings elucidate YAP1-mediated glutamine metabolism as a crucial bypass mechanism against DFMO, following the inhibition of polyamine metabolism. Our study provides valuable insights into the potential role of DFMO in an "One-two Punch" therapy of metastatic and recurrent osteosarcoma.