Cellular Status Research Articles

HPV and p53 status as precision determinants of head and neck cancer response to DNA-PKcs inhibition in combination with irradiation.

Major risk factors of head and neck squamous cell carcinoma (HNSCC) are tobacco use and human papillomavirus (HPV). HPV E6 oncoprotein leads to p53 degradation, whereas HPV-negative cancers are frequently associated with TP53 mutations. Peposertib is a potent and selective, orally administered small-molecule inhibitor of the catalytic subunit of the DNA-dependent kinase (DNA-PKcs), a key regulator of non-homologous end joining (NHEJ). NHEJ inhibition along with irradiation (IR)-induced DNA double-strand breaks has the potential to increase antitumor treatment efficacy. Here, we investigated the responses of a panel of HNSCC models with distinct HPV and p53 status to treatments with IR, DNA-PKcs inhibition, and their combination in-vitro and in-vivo. IR-induced DNA damage combined with peposertib administration shortly before IR results in decreased cell viability and proliferation and causes DNA repair delay in all studied HNSCC cell lines. However, our data confirm that the actual cell fate upon this treatment is determined by cellular p53 and/or HPV status. Cells lacking functional p53 due to its degradation by HPV or due to a loss-of-function mutation are arrested in the G2/M phase of the cell cycle and eliminated by apoptosis whereas p53-proficient HNSCC cell lines preferentially undergo senescence. This is also recapitulated in-vivo, where HPV+ UD-SCC-2 xenografts display stronger and more durable responses to the combined treatment as compared to p53 wild-type UM-SCC-74A tumors. In conclusion, DNA-PKcs inhibitor peposertib should be further studied as a potential radiosensitizer for HNSCCs, taking into consideration the genetic background and the HPV status of a particular tumor.

Immune System Modulation by Extracellular Vesicles: Implications for Disease Treatment

Extracellular vesicles (EVs), including exosomes and microvesicles, have emerged as crucial mediators of intercellular communication, playing a significant role in immune system modulation. These nanosized vesicles transfer bioactive molecules such as proteins, lipids, and nucleic acids, influencing immune responses and contributing to various disease processes, including cancer, autoimmune disorders, and infections. The dual functionality of EVs capable of either activating or suppressing immune responses depending on their origin and cargo highlights their therapeutic potential. This review explores the mechanisms through which EVs modulate immune functions, their implications in disease pathogenesis, and their innovative applications in therapeutic strategies. In oncology, tumor-derived EVs can promote immune evasion, while engineered EVs show promise as vehicles for targeted drug delivery and cancer immunotherapy. In autoimmune diseases, EVs can either exacerbate inflammation or facilitate tolerance, offering new avenues for treatment. Furthermore, EVs hold potential as biomarkers for disease diagnosis and monitoring due to their stability in bodily fluids and ability to reflect cellular states. However, challenges remain in standardizing EV isolation, characterization, and clinical application. Future advancements in bioengineering, along with improved understanding of EV biology, are crucial for harnessing their therapeutic potential. This review emphasizes the importance of EVs in immune modulation and their promising implications for innovative disease treatment strategies. Keywords: Extracellular vesicles, immune modulation, cancer therapy, autoimmune diseases, biomarkers

Exploring heterogeneous cell population dynamics in different microenvironments by novel analytical strategy based on images.

Understanding the dynamic states and transitions of heterogeneous cell populations is crucial for addressing fundamental biological questions. High-content imaging provides rich datasets, but it remains increasingly difficult to integrate and annotate high-dimensional and time-resolved datasets to profile heterogeneous cell population dynamics in different microenvironments. Using hepatic stellate cells (HSCs) LX-2 as model, we proposed a novel analytical strategy for image-based integration and annotation to profile dynamics of heterogeneous cell populations in 2D/3D microenvironments. High-dimensional features were extracted from extensive image datasets, and cellular states were identified based on feature profiles. Time-series clustering revealed distinct temporal patterns of cell shape and actin cytoskeleton reorganization. We found LX-2 showed more complex membrane dynamics and contractile systems with an M-shaped actin compactness trend in 3D culture, while they displayed rapid spreading in early 2D culture. This image-based integration and annotation strategy enhances our understanding of HSCs heterogeneity and dynamics in complex extracellular microenvironments.

BreCML: identifying breast cancer cell state in scRNA-seq via machine learning

Breast cancer is a prevalent malignancy and one of the leading causes of cancer-related mortality among women worldwide. This disease typically manifests through the abnormal proliferation and dissemination of malignant cells within breast tissue. Current diagnostic and therapeutic strategies face significant challenges in accurately identifying and localizing specific subtypes of breast cancer. In this study, we developed a novel machine learning-based predictor, BreCML, designed to accurately classify subpopulations of breast cancer cells and their associated marker genes. BreCML exhibits outstanding predictive performance, achieving an accuracy of 98.92% on the training dataset. Utilizing the XGBoost algorithm, BreCML demonstrates superior accuracy (98.67%), precision (99.15%), recall (99.49%), and F1-score (99.79%) on the test dataset. Through the application of machine learning and feature selection techniques, BreCML successfully identified new key genes. This predictor not only serves as a powerful tool for assessing breast cancer cellular status but also offers a rapid and efficient means to uncover potential biomarkers, providing critical insights for precision medicine and therapeutic strategies.

Interactions between blood lead (Pb) concentration, oxidative stress, cellular immune response and reproductive status in livestock from a mining area

Chronic exposure to lead (Pb) in livestock grazing in abandoned mining areas affects animal welfare and productivity, as well as represents a significant food safety risk. Here, we evaluate the physiological effects of Pb exposure in goats maintained under extensive farming conditions in a non-remediated mining area. We monitored blood, fecal, and milk Pb levels in two groups of goats, pregnant (n=17) and lactating (n=24), kept in different enclosures with high soil Pb concentrations (geometric means of 270 and 143 μg/g, respectively) in Sierra Madrona mining district (Spain). We also studied the influence of Pb exposure on the ability to mount a cellular immune response, and on oxidative stress and biochemical biomarkers measured in blood. Blood Pb concentration was higher in pregnant than in lactating goats, but this difference was not observed in fecal Pb concentration. Pb levels in feces and milk concentrations were correlated with those measured in blood, with 11% of milk samples showing Pb concentrations above the maximum level (ML) for Pb in raw milk established by the EU (0.02 μg/g wet weight). Animals with increased blood Pb levels showed reduced concentrations of retinol in plasma, but these Pb levels did not affect the cellular immune response. The stimulation of the cellular immune response in lactating goats was associated with an increase in blood Pb and calcium (Ca) levels. The reproductive status and age of goats significantly affected several oxidative stress, antioxidants and plasma biochemistry variables. Goats grazing on soils contaminated by past Pb mining activities may be susceptible to detrimental health effects mediated by retinol deficiency. In view of the detected transfer of Pb through milk, special attention should be paid to the food safety of derived products (i.e. cheese).

Single-cell transcriptional mapping reveals genetic and non-genetic determinants of aberrant differentiation in AML.

In acute myeloid leukemia (AML), genetic mutations distort hematopoietic differentiation, resulting in the accumulation of leukemic blasts. Yet, it remains unclear how these mutations intersect with cellular origins and whether they converge upon similar differentiation patterns. Single-cell RNA sequencing (scRNA-seq) has enabled high-resolution mapping of the relationship between leukemia and normal cell states, yet this application is hampered by imprecise reference maps of normal hematopoiesis and small sample sizes among patient cohorts. As a first step we constructed a reference atlas of human bone marrow hematopoiesis from 263,519 single-cell transcriptomes spanning 55 cellular states, that was benchmarked against independent datasets of immunophenotypically pure hematopoietic stem and progenitor cells. Using this reference atlas, we mapped over 1.2 million single-cell transcriptomes spanning 318 AML, mixed phenotype acute leukemia (MPAL), and acute erythroid leukemia (AEL) samples. This large-scale analysis, together with systematic mapping of genotype-to-phenotype associations between driver mutations and differentiation landscapes, revealed convergence of diverse genetic alterations on twelve recurrent patterns of aberrant differentiation in AML. This included unconventional lymphoid and erythroid priming linked to RUNX1 and TP53 mutations, respectively. We also identified non-genetic determinants of AML differentiation such as two subgroups of KMT2A-rearranged AML that differ in the identity of their leukemic stem cells (LSCs), likely reflecting distinct cellular origins. Furthermore, distinct LSC-driven hierarchies can co-exist within individual patients, providing insights into AML evolution. Together, precise mapping of normal and malignant cell states provides a framework for advancing the study and disease classification of hematologic malignancies thereby informing therapy development.

HCMV strain- and cell type-specific alterations in membrane contact sites point to the convergent regulation of organelle remodeling.

Viruses are ubiquitous entities that infect organisms across the kingdoms of life. While viruses can infect a range of cells, tissues, and organisms, this aspect is often not explored in cell culture analyses. There is limited information about which infection-induced changes are shared or distinct in different cellular environments. The prevalent pathogen human cytomegalovirus (HCMV) remodels the structure and function of subcellular organelles and their interconnected networks formed by membrane contact sites (MCSs). A large portion of this knowledge has been derived from fibroblasts infected with a lab-adapted HCMV strain. Here, we assess strain- and cell type-specific alterations in MCSs and organelle remodeling induced by HCMV. Integrating quantitative mass spectrometry, super-resolution microscopy, and molecular virology assays, we compare infections with lab-adapted and low-passage HCMV strains in fibroblast and epithelial cells. We determine that, despite baseline proteome disparities between uninfected fibroblast and epithelial cells, infection induces convergent changes and is remarkably similar. We show that hallmarks of HCMV infection in fibroblasts, mitochondria-endoplasmic reticulum (ER) encapsulations and peroxisome proliferation, are also conserved in infected epithelial and macrophage-like cells. Exploring cell type-specific differences, we demonstrate that fibroblasts rely on endosomal cholesterol transport while epithelial cells rely on cholesterol from the Golgi. Despite these mechanistic differences, infections in both cell types result in phenotypically similar cholesterol accumulation at the viral assembly complex. Our findings highlight the adaptability of HCMV, in that infections can be tailored to the initial cell state by inducing both shared and unique proteome alterations, ultimately promoting a unified pro-viral environment.IMPORTANCEHuman cytomegalovirus (HCMV) establishes infections in diverse cell types throughout the body and is connected to a litany of diseases associated with each of these tissues. However, it is still not fully understood how HCMV replication varies in distinct cell types. Here, we compare HCMV replication with lab-adapted and low-passage strains in two primary sites of infection, lung fibroblasts and retinal epithelial cells. We discover that, despite displaying disparate protein compositions prior to infection, these cell types undergo convergent alterations upon HCMV infection, reaching a more similar cellular state late in infection. We find that remodeling of the subcellular landscape is a pervasive feature of HCMV infection, through alterations to both organelle structure-function and the interconnected networks they form via membrane contact sites. Our findings show how HCMV infection in different cell types induces both shared and divergent changes to cellular processes, ultimately leading to a more unified state.

Overexpression of Chromatin Remodeling Factor SRG3 Down-Regulates IL1β-Expressing M1 Macrophages and IL17-Producing T Cells in Adipose Tissues.

The SWItch3-related gene (SRG3) is a core component of ATP-dependent SWI/SNF complexes, which are crucial for regulating immune cell development and function (e.g., macrophages and CD4+ T cells), embryonic development, and non-immune cell differentiation. Notably, SRG3 overexpression has been shown to polarize macrophages in the central nervous system toward an anti-inflammatory M2 phenotype, thereby protecting against the development of experimental autoimmune encephalomyelitis in mice. However, the effect of SRG3 on immune responses in adipose tissues remains unclear. To address this issue, we examined the cellularity and inflammatory status of adipose tissue in B10.PL mice overexpressing the SRG3 gene under the ubiquitous β-actin promoter (SRG3β-actin). Interestingly, SRG3 overexpression significantly reduced adipocyte size in both white and brown adipose tissues, without affecting the overall adipose tissue weight. Such phenotypic effects might be associated with the improved glucose tolerance observed in SRG3β-actin B10.PL mice. Moreover, we found that SRG3 overexpression down-regulates IL1β-expressing M1 macrophages, leading to a significant decrease in the M1/M2 macrophage ratio. Additionally, SRG3β-actin B10.PL mice showed a dramatic reduction in neutrophils as well as IL1β- and IL17-producing T cells in adipose tissues. Taken together, our results indicate that SRG3 plays a vital role in maintaining immune homeostasis within adipose tissues.

Comparative Analysis of Pretreatment Methods for Fruit Waste Valorization in Euglena gracilis Cultivation: Impacts on Biomass, β-1,3-Glucan Production, and Photosynthetic Efficiency.

This study explored the sustainable valorization of fruit waste extracts from sugarcane bagasse (SB), banana peel (BP), and watermelon rind (WR) for Euglena gracilis biomass and β-1,3-glucan production. The extracts were prepared using water extraction (WE), high-temperature and pressure treatment (HTP), and dilute sulfuric acid treatment (DSA). The DSA-treated extracts consistently yielded the best results. E. gracilis cultured in SB-DSA showed the highest cell density with a 2.08-fold increase compared to the commercial HUT medium, followed by BP-DSA (1.35-fold) and WR-DSA (1.70-fold). Photosynthetic pigment production increased significantly, with chlorophyll a yield being highest in SB-DSA (1.90-fold increase). The chlorophyll a/b ratio and total carotenoid content also improved, indicating enhanced light-harvesting capacity and photoprotection. Photosynthetic efficiency, measured by chlorophyll fluorescence, notably improved. The maximum quantum yield of PSII (Fv/Fm) increased by up to 25.88% in SB-DSA, suggesting reduced stress and improved overall photosynthetic health. The potential photochemical efficiency (Fv/F0) showed even greater improvements: up to 40.53% in SB-DSA. Cell morphology analysis revealed larger cell aspect ratios, implying a more active cellular physiological state. β-1,3-glucan yield also increased by 23.99%, 12.92%, and 23.38% in SB-DSA, BP-DSA, and WR-DSA, respectively. This study demonstrates the potential of pretreated fruit waste as a cost-effective and sustainable medium for E. gracilis cultivation, offering the dual benefits of waste valorization and high-value compound production. These findings contribute to the development of more efficient biorefinery processes and align with the circular economy principles in food biotechnology.

Restoration of autophagy reduces diabetes-induced endothelial dysfunction

Abstract Introduction Diabetes leads to endothelial dysfunction, a main determinant of several cardiovascular diseases. The molecular mechanisms underlying the effects of hyperglycemia in endothelial cells are not fully characterized. Autophagy, the intracellular process by which the cell digests and recycles senescent or damaged cytoplasmic elements, exerts cardiovascular protective effects, limiting cardiac and vascular injury in the presence of stress. However, it is unclear how hyperglycemia modulates autophagy in endothelial cells. Purpose In this study, we elucidated the role of autophagy in vascular damage induced by diabetes. We also tested whether the restoration autophagy attenuates diabetes-induced endothelial damage. Methods We evaluated the effects of high-glucose (HG, 30 mM for 6 and 24 hours) on markers of endothelial function, autophagy, autophagic flux, and mitophagy in human umbilical endothelial cells (HUVEC) in vitro and in mesenteric arteries from wild-type mice (WT) ex vivo. We tested the effects of autophagy reactivation using the natural polyamine spermidine or ATG7 overexpression (ATG7ov) on apoptosis and angiogenesis in HUVEC treated with HG. Vascular reactivity experiments in the presence of autophagy activation were performed in HG-treated mouse mesenteric arteries and human saphenous veins from patients with peripheral artery disease. Finally, we evaluated the level of autophagy in the mammary arteries of newly discovered diabetic patients undergoing coronary artery bypass graft surgery. Results We found that HG reduces autophagy (0.6 fold p<0.05) and mitophagy (1.5 fold p<0.001) in HUVECs. We also demonstrated that endothelial cells undergoing hyperglycemia fail to activate autophagy under hypoxic conditions (0.6 fold p<0.05). Reactivation of autophagy by ATG7ov rescues apoptosis (0.52 fold p<0.05) and angiogenesis (2.3 fold p<0.05) in HUVEC treated with HG. We further observed that HG exacerbates endothelial dysfunction in a mouse model of genetic inhibition (Beclin 1 +/- mice), compared to WT mice (-19.16 % +-4.97 SEM vs -48.39 % +-2.18 SEM p<0.001). Mechanistically, HG increases cellular acetylation status (0.7 fold p<0.05) and activates p300 (1 fold p<0.05), an autophagy inhibitor. ATG7ov or spermidine, a p300 inhibitor, rescue endothelial-dependent relaxation in mesenteric arteries of WT mice treated with HG (ATG7ov -62.48 % +-5.16 SEM; SP -63.01 +-3.22 SEM; HG -40.67 % +-3.82 p<0.001). Finally, we observed reduced levels of autophagy in mammary arteries from diabetic patients and demonstrated that SP improves vascular function in human saphenous veins (-37.6 % +-12.76 SEM vs -12.52 % +-5.6 SEM p<0.001). Conclusion Our results suggest that the impairment of autophagy is a strong contributor of diabetes induced-endothelial dysfunction. Targeting autophagy may represent a valid therapeutic strategy to counteract the cardiovascular consequences of metabolic stress.

Non-genetic differences underlie variability in proliferation among esophageal epithelial clones.

Individual cells grown in culture exhibit remarkable differences in their growth, with some cells capable of forming large clusters, while others are limited or fail to grow at all. While these differences have been observed across cell lines and human samples, the growth dynamics and associated cell states remain poorly understood. In this study, we performed clonal tracing through imaging and cellular barcoding of an in vitro model of esophageal epithelial cells (EPC2-hTERT). We found that about 10% of clones grow exponentially, while the remaining have cells that become non-proliferative leading to a halt in the growth rate. Using mathematical models, we demonstrate two distinct growth behaviors: exponential and logistic. Further, we discovered that the propensity to grow exponentially is largely heritable through four doublings and that the less proliferative clones can become highly proliferative through increasing plating density. Combining barcoding with single-cell RNA-sequencing (scRNA-seq), we identified the cellular states associated with the highly proliferative clones, which include genes in the WNT and PI3K pathways. Finally, we identified an enrichment of cells resembling the highly proliferative cell state in the proliferating healthy human esophageal epithelium.

Collapsible tree: interactive web app to present collapsible hierarchies.

A crucial component of intuitive data visualization is presenting a hierarchical tree structure with interactive functions. For example, single-cell transcriptomics studies may generate gene expression values with developmental trajectories or cell lineage structures. Two common visualization methods, t-SNE and UMAP, require two separate figures to depict the distribution of cell types and gene expression data, with low-dimension projections that may not capture the hierarchical structures among cells. Here, we present a JavaScript framework and an interactive web app named Collapsible Tree, which presents values jointly with interactive, expandable, and collapsible lineage structures. For example, the Collapsible Tree presents cellular states and gene expression from single-cell transcriptomics within a single hierarchical plot, enabling comparisons of gene expression across lineages and subtle patterns between sub-lineages. Our framework can facilitate the exploration of complicated value patterns that are not evident in UMAP or t-SNE plots. The Collapsible Tree web interface is available at https://collapsibletree.data2in.net. The JavaScript library source code is available at https://github.com/data2intelligence/collapsible_tree.

The role of immuno-mediated dysregulation in the progression of allergic pathology in military personnel under occupational stress

In order to identify clinical and immunological predictors of the progression of allergopathology in military personnel participating in special operations under conditions of professional stress, 43 military personnel participating in special operations divided into two groups were examined. Group 1 consisted of officers with allergopathology or who first debuted symptoms of allergic diseases during or within 6 months after participating in special operations (n = 13, average age 36.4±4.5 years). Group 2 included officers participating in special operations who did not have symptoms of allergic diseases (n = 13, average age 36.4±4.5 years). The analysis of complaints and medical documentation were carried out. Clinical and laboratory examination was performed without exacerbation of somatic pathology. The immune status was assessed by the expression of CD3+, CD4+, CD8+, CD16+, CD19+, HLA-DR+, intracellular FoxP3 content in CD4+CD25+T cells, granzyme B in CD3-CD16+ and CD3+CD8+ lymphocytes using appropriate monoclonal antibodies (Beckman Coulter) and taking into account the results on the cytofluorometer “FC 500”. Immunological monitoring was performed before participation in hostilities and 6 months after return. A comparative assessment of the cellular and humoral state of military personnel of both comparison groups before leaving for an area with an unfavorable operational situation revealed the following differences. In the group of military personnel with allergic manifestations, significantly fewer CD4+ lymphocytes were noted, as well as significantly fewer CD3+CD4+CD25+FoxP3 regulatory lymphocytes and an increase in the number of circulating B lymphocytes were recorded. When dynamically monitoring the parameters of the cellular and humoral immune response in military personnel participating in hostilities, 6 months after returning from a business trip to areas with an unfavorable operational situation, unidirectional changes in the immune status were recorded in the form of a violation of the differentiation processes of the T cell link of the immune system. In the group of servicemen suffering from allergic diseases, the revealed changes were accompanied by a weakening of the processes of physiological immunosuppression in the form of a persistent decrease in the content of regulatory T lymphocytes in the dynamics of observation for 6 months.

Tobacco smoke exposure is a driver of altered oxidative stress response and immunity in head and neck cancer.

Exposomes are critical drivers of carcinogenesis. However, how they modulate tumor behavior remains unclear. Extensive clinical data link cigarette smoke as a key exposome that promotes aggressive tumors, higher rates of metastasis, reduced response to chemoradiotherapy, and suppressed anti-tumor immunity. We sought to determine whether smoke itself can modulate aggressive tumor behavior in head and neck squamous cell carcinoma (HNSCC) through reprogramming the cellular reductive state. Using established human and murine HNSCC cell lines and syngeneic mouse models, we utilized conventional western blotting, steady state and flux metabolomics, RNA sequencing, quantitative proteomics and flow cytometry to analyze the impact of smoke exposure on HNSCC tumor biology. Cigarette smoke persistently activated Nrf2 target genes essential for maintenance of the cellular reductive state and survival under conditions of increased oxidative stress in HNSCC regardless of HPV status. In contrast to e-cigarette vapor, conventional cigarette smoke mobilizes cellular metabolism toward oxidative stress adaptation, resulting in development of cross-resistance to cisplatin. In parallel, smoke exposure modulates both expression of PDL1 and the secretory phenotype of HNSCC cells through activation of NF-κB resulting in an altered tumor immune microenvironment (TIME) in syngeneic mouse models and altered PBMC differentiation that includes downregulated expression of antigen presentation and costimulatory genes in myeloid cells. Cigarette smoke exposome is a potent activator of the Nrf2 pathway and is a likely primary trigger for the tripartite phenotype of aggressive HNSCC consisting of: 1) reduced chemotherapy sensitivity, 2) enhanced metastatic potential and 3) suppressed anti-tumor immunity. The smoke exposome drives aggressive tumor behavior, treatment resistance and suppressed immunity through coordinated metabolic reprogramming. Successfully targeting this adaptation is critical to improving survival in smokers with head and neck cancer.

Metabolomic signature of sperm in men with obesity-associated asthenozoospermia.

Obese men have a significantly increased risk of developing asthenozoospermia. Sperm motility is directly related to cellular energy supply and metabolic status. Sperm metabolomics research based on Gas chromatography-mass spectrometry (GC-MS) technology can provide useful information for the pathological mechanism, diagnosis, and treatment of obesity-associated asthenozoospermia. Sperm samples were obtained from a healthy control group (n = 49) and patients with obesity-associated asthenozoospermia (n = 40). After the analysis of sperm samples using GC-MS, various multivariate statistical methods such as principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and orthogonal partial least squares-discriminant analysis (OPLS-DA) were conducted. A total of 56 metabolites were identified in the sperm samples. Among them, 19 differential metabolites were found between the two groups. Metabolites such as glutamic acid, fumaric acid, and cysteine were significantly downregulated in the sperm of patients with obesity-associated asthenozoospermia, while metabolites like palmitic acid, stearic acid, and alanine were significantly upregulated. The differential metabolites were enriched in D-glutamine and D-glutamate metabolism; proline, aspartate, and glutamate metabolism; glutathione metabolism and the other metabolic pathways. Obesity may influence the composition of metabolic products in sperm, and metabolomic analysis proves beneficial for the future diagnosis and treatment of obesity-associated asthenozoospermia.

Secreted Apoe rewires melanoma cell state vulnerability to ferroptosis.

A major therapeutic barrier in melanoma is the coexistence of diverse cellular states marked by distinct metabolic traits. Transitioning from a proliferative to an invasive melanoma phenotype is coupled with increased ferroptosis vulnerability. However, the regulatory circuits controlling ferroptosis susceptibility across melanoma cell states are unknown. In this work, we identified Apolipoprotein E (APOE) as the top lipid-metabolism gene segregating the melanoma MITFhigh/AXLlow proliferative/ferroptosis-resistant from MITFlow/AXLhigh invasive/ferroptosis-sensitive state. Mechanistically, ApoE secreted by the MITFhigh/AXLlow cells protects the invasive phenotype from ferroptosis-inducing agents by reducing the content of peroxidation-prone polyunsaturated fatty acids and boosting GPX4 levels both in vitro and in vivo. Whole-exome sequencing indicates that APOEhigh expression in patients with melanoma is associated with resistance to ferroptosis, regardless of APOE germline status. In aggregate, we found a ferroptosis-resistance mechanism between melanoma cell states relying on secreted ApoE and APOEhigh expression as a potential biomarker for poor ferroptosis response in melanoma.

Autophagy is required for mammary tumor recurrence by promoting dormant tumor cell survival following therapy

BackgroundMortality from breast cancer is principally due to tumor recurrence. Recurrent breast cancers arise from the pool of residual tumor cells, termed minimal residual disease, that survive treatment and may exist in a dormant state for 20 years or more following treatment of the primary tumor. As recurrent breast cancer is typically incurable, understanding the mechanisms underlying dormant tumor cell survival is a critical priority in breast cancer research. The importance of this goal is further underscored by emerging evidence suggesting that targeting dormant residual tumor cells in early-stage breast cancer patients may be a means to prevent tumor recurrence and its associated mortality. In this regard, the role of autophagy in dormant tumor cell survival and recurrence remains unresolved, with conflicting reports of both pro-survival/recurrence-promoting and pro-death/recurrence-suppressing effects of autophagy inhibition in dormant tumor cells. Resolving this question has important clinical implications.MethodsWe used genetically engineered mouse models that faithfully recapitulate key features of human breast cancer progression, including minimal residual disease, tumor dormancy, and recurrence. We used genetic and pharmacological approaches to inhibit autophagy, including treatment with chloroquine, genetic knockdown of ATG5 or ATG7, or deletion of BECN and determined their effects on dormant tumor cell survival and recurrence.ResultsWe demonstrate that the survival and recurrence of dormant mammary tumor cells following therapy is dependent upon autophagy. We find that autophagy is induced in vivo following HER2 downregulation and remains activated in dormant residual tumor cells. Using genetic and pharmacological approaches we show that inhibiting autophagy by chloroquine administration, ATG5 or ATG7 knockdown, or deletion of a single allele of the tumor suppressor Beclin 1 is sufficient to inhibit mammary tumor recurrence, and that autophagy inhibition results in the death of dormant mammary tumor cells in vivo.ConclusionsOur findings demonstrate a pro-tumorigenic role for autophagy in tumor dormancy and recurrence following therapy, reveal that dormant tumor cells are uniquely reliant upon autophagy for their survival, and indicate that targeting dormant residual tumor cells by inhibiting autophagy impairs tumor recurrence. These studies identify a pharmacological target for a cellular state that is resistant to commonly used anti-neoplastic agents and suggest autophagy inhibition as an approach to reduce dormant minimal residual disease in order to prevent lethal tumor recurrence.

Therapeutic targeting of differentiation-state dependent metabolic vulnerabilities in diffuse midline glioma

H3K27M diffuse midline gliomas (DMG), including diffuse intrinsic pontine gliomas (DIPG), exhibit cellular heterogeneity comprising less-differentiated oligodendrocyte precursors (OPC)-like stem cells and more differentiated astrocyte (AC)-like cells. Here, we establish in vitro models that recapitulate DMG-OPC-like and AC-like phenotypes and perform transcriptomics, metabolomics, and bioenergetic profiling to identify metabolic programs in the different cellular states. We then define strategies to target metabolic vulnerabilities within specific tumor populations. We show that AC-like cells exhibit a mesenchymal phenotype and are sensitized to ferroptotic cell death. In contrast, OPC-like cells upregulate cholesterol biosynthesis, have diminished mitochondrial oxidative phosphorylation (OXPHOS), and are accordingly more sensitive to statins and OXPHOS inhibitors. Additionally, statins and OXPHOS inhibitors show efficacy and extend survival in preclinical orthotopic models established with stem-like H3K27M DMG cells. Together, this study demonstrates that cellular subtypes within DMGs harbor distinct metabolic vulnerabilities that can be uniquely and selectively targeted for therapeutic gain.

Functional Conservation of the DDP1-type Inositol Pyrophosphate Phosphohydrolases in Land Plant.

Inositol pyrophosphates (PP-InsPs) are eukaryote-specific second messengers that regulate diverse cellular processes, including immunity, nutrient sensing, and hormone signaling pathways in plants. These energy-rich messengers exhibit high sensitivity to the cellular phosphate status, suggesting that the synthesis and degradation of PP-InsPs are tightly controlled within the cells. Notably, the molecular basis of PP-InsP hydrolysis in plants remains largely unexplored. In this study, we report the functional characterization of MpDDP1, a diadenosine and diphosphoinositol polyphosphate phosphohydrolase encoded by the genome of the liverwort, Marchantia polymorpha. We show that MpDDP1 functions as a PP-InsP phosphohydrolase in different heterologous organisms. Consistent with this finding, M. polymorpha plants defective in MpDDP1 exhibit elevated levels of 1/3-InsP7 and 1/3,5-InsP8, highlighting the contribution of MpDDP1 in regulating PP-InsP homeostasis in planta. Furthermore, our study reveals that MpDDP1 controls thallus development and vegetative reproduction in M. polymorpha. Collectively, this study provides insights into the regulation of specific PP-InsP messengers by DDP1-type phosphohydrolases in land plants.

Effect of gut microbiota intervention on inflammatory responses and cellular immune function in hepatocellular carcinoma patients undergoing radiotherapy

ObjectiveTo analyze the changes in nutritional status, inflammatory response and cellular immune status of Hepatocellular Carcinoma (HCC) patients who received radiotherapy under GMB intervention and to clarify the effect of GMB intervention on HCC. MethodsNinety-two patients with HCC receiving radiotherapy were randomized into study and observation groups, 46 in each group. The control group used conventional radiotherapy, and the study group used the gut microbiota intervention. The gut microbiota before and after radiotherapy, and the liver function, clinical efficacy, inflammatory response, cellular immunity, and nutritional status before and after treatment were compared. ResultsCompared with the control group, the number of lactobacillus and Bifidobacterium increased significantly, the clinical efficacy was significantly enhanced, the liver function, cellular immunity and nutritional status were significantly improved, and the inflammatory response was significantly reduced, with statistically significant differences (P < 0.05). Conclusiongut microbiota intervention can improve the effect of radiotherapy and improve liver function in patients, and the mechanism is related to regulating cellular immune function of patients and inhibiting inflammatory response in patients.