ABSTRACT
Polypyrimidine tract-binding protein 1 (PTBP1) plays an essential role in splicing and post-transcriptional regulation. Moreover, PTBP1 has been implicated as a causal factor in tumorigenesis. However, the involvement of PTBP1 in cellular senescence, a key biological process in aging and cancer suppression, remains to be clarified. Here, it is shown that PTBP1 is associated with the facilitation of tumor growth and the prognosis in lung adenocarcinoma (LUAD). PTBP1 exhibited significantly increased expression in various cancer types including LUAD and showed consistently decreased expression in multiple cellular senescence models. Suppression of PTBP1 induced cellular senescence in LUAD cells. In terms of molecular mechanisms, the silencing of PTBP1 enhanced the skipping of exon 3 in F-box protein 5 (FBXO5), resulting in the generation of a less stable RNA splice variant, FBXO5-S, which subsequently reduces the overall FBXO5 expression. Additionally, downregulation of FBXO5 was found to induce senescence in LUAD. Collectively, these findings illustrate that PTBP1 possesses an oncogenic function in LUAD through inhibiting senescence, and that targeting aberrant splicing mediated by PTBP1 has therapeutic potential in cancer treatment.
ABSTRACT
Abnormal transcription initiation from alternative first exon has been reported to promote tumorigenesis. However, the prevalence and impact of gene expression regulation mediated by alternative tandem transcription initiation were mostly unknown in cancer. Here, we developed a robust computational method to analyze alternative tandem transcription start site (TSS) usage from standard RNA sequencing data. Applying this method to pan-cancer RNA sequencing datasets, we observed widespread dysregulation of tandem TSS usage in tumors, many of which were independent of changes in overall expression level or alternative first exon usage. We showed that the dynamics of tandem TSS usage was associated with epigenomic modulation. We found that significant 5' untranslated region shortening of gene TIMM13 contributed to increased protein production, and up-regulation of TIMM13 by CRISPR-mediated transcriptional activation promoted proliferation and migration of lung cancer cells. Our findings suggest that dysregulated tandem TSS usage represents an addtional layer of cancer-associated transcriptome alterations.
Subject(s)
Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Neoplasms , Transcription Initiation Site , Transcriptome , Humans , Gene Expression Profiling/methods , Neoplasms/genetics , Cell Line, Tumor , Cell Proliferation/geneticsABSTRACT
Recent research has revealed that N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) constitutes a significant risk factor in the development of esophageal cancer. Several investigations have elucidated the beneficial impact of folic acid (FA) in safeguarding esophageal epithelial cells against MNNG-induced damage. Therefore, we hypothesized that FA might prevent MNNG-induced proliferation of esophageal epithelial cells by interfering with the PI3K/AKT/mTOR signaling pathway. In vivo experiments, we found that FA antagonized MNNG-induced proliferation of rat esophageal mucosal epithelial echinocytes and activation of the PI3K/AKT/mTOR signaling pathway. In our in vitro experiments, it was observed that acute exposure to MNNG for 24 h led to a decrease in proliferative capacity and inhibition of the PI3K/AKT/mTOR signaling pathway in an immortalized human normal esophageal epithelial cell line (Het-1A), which was also ameliorated by supplementation with FA. We successfully established a Het-1A-T-cell line by inducing malignant transformation in Het-1A cells through exposure to MNNG. Notably, the PI3K/AKT2/mTOR pathway showed early suppression followed by activation during this transition. Next, we observed that FA inhibited cell proliferation and activation of the PI3K/AKT2/mTOR signaling pathway in Het-1A-T malignantly transformed cells. We further investigated the impact of 740Y-P, a PI3K agonist, and LY294002, a PI3K inhibitor, on Het-1A-T-cell proliferation. Overall, our findings show that FA supplementation may be beneficial in safeguarding normal esophageal epithelial cell proliferation and avoiding the development of esophageal cancer by decreasing the activation of the MNNG-induced PI3K/AKT2/mTOR signaling pathway.
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OBJECTIVE: To construct the deep learning convolution neural network (CNN) model and machine learning support vector machine (SVM) model of bone remodeling of chronic maxillary sinusitis (CMS) based on CT image data to improve the accuracy of image diagnosis. METHODS: Maxillary sinus CT data of 1000 samples in 500 patients from January 2018 to December 2021 in our hospital was collected. The first part is the establishment and testing of chronic maxillary sinusitis detection model by 461 images. The second part is the establishment and testing of the detection model of chronic maxillary sinusitis with bone remodeling by 802 images. The sensitivity, specificity and accuracy and area under the curve (AUC) value of the test set were recorded, respectively. RESULTS: Preliminary application results of CT based AI in the diagnosis of chronic maxillary sinusitis and bone remodeling. The sensitivity, specificity and accuracy of the test set of 93 samples of CMS, were 0.9796, 0.8636 and 0.9247, respectively. Simultaneously, the value of AUC was 0.94. And the sensitivity, specificity and accuracy of the test set of 161 samples of CMS with bone remodeling were 0.7353, 0.9685 and 0.9193, respectively. Simultaneously, the value of AUC was 0.89. CONCLUSION: It is feasible to use artificial intelligence research methods such as deep learning and machine learning to automatically identify CMS and bone remodeling in MSCT images of paranasal sinuses, which is helpful to standardize imaging diagnosis and meet the needs of clinical application.
Subject(s)
Bone Remodeling , Deep Learning , Maxillary Sinusitis , Sensitivity and Specificity , Support Vector Machine , Tomography, X-Ray Computed , Humans , Maxillary Sinusitis/diagnostic imaging , Tomography, X-Ray Computed/methods , Chronic Disease , Female , Male , Middle Aged , Adult , Neural Networks, Computer , Aged , Artificial IntelligenceABSTRACT
Intronic polyadenylation (IPA) is an RNA 3' end processing event which has been reported to play important roles in cancer development. However, the comprehensive landscape of IPA events across various cancer types is lacking. Here, we apply IPAFinder to identify and quantify IPA events in 10,383 samples covering all 33 cancer types from The Cancer Genome Atlas (TCGA) project. We totally identify 21,835 IPA events, almost half of which are ubiquitously expressed. We identify 2761 unique dynamically changed IPA events across cancer types. Furthermore, we observe 8855 non-redundant clinically relevant IPA events, which could potentially be used as prognostic indicators. Our analysis also reveals that dynamic IPA usage within cancer signaling pathways may affect drug response. Finally, we develop a user-friendly data portal, IPACancer Atlas (http://www.tingni-lab.com/Pancan_IPA/), to search and explore IPAs in cancer.
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Methylation quantitative trait loci (mQTLs) are essential for understanding the role of DNA methylation changes in genetic predisposition, yet they have not been fully characterized in East Asians (EAs). Here we identified mQTLs in whole blood from 3,523 Chinese individuals and replicated them in additional 1,858 Chinese individuals from two cohorts. Over 9% of mQTLs displayed specificity to EAs, facilitating the fine-mapping of EA-specific genetic associations, as shown for variants associated with height. Trans-mQTL hotspots revealed biological pathways contributing to EA-specific genetic associations, including an ERG-mediated 233 trans-mCpG network, implicated in hematopoietic cell differentiation, which likely reflects binding efficiency modulation of the ERG protein complex. More than 90% of mQTLs were shared between different blood cell lineages, with a smaller fraction of lineage-specific mQTLs displaying preferential hypomethylation in the respective lineages. Our study provides new insights into the mQTL landscape across genetic ancestries and their downstream effects on cellular processes and diseases/traits.
Subject(s)
DNA Methylation , East Asian People , Quantitative Trait Loci , Female , Humans , Male , East Asian People/genetics , Genetic Predisposition to Disease , Genome-Wide Association Study/methods , Multifactorial Inheritance , Polymorphism, Single NucleotideABSTRACT
In the challenging tumor microenvironment (TME), tumors coexist with diverse stromal cell types. During tumor progression and metastasis, a reciprocal interaction occurs between cancer cells and their environment. These interactions involve ongoing and evolving paracrine and proximal signaling. Intrinsic signal transduction in tumors drives processes such as malignant transformation, epithelial-mesenchymal transition, immune evasion, and tumor cell metastasis. In addition, cancer cells embedded in the tumor microenvironment undergo metabolic reprogramming. Their metabolites, serving as signaling molecules, engage in metabolic communication with diverse matrix components. These metabolites act as direct regulators of carcinogenic pathways, thereby activating signaling cascades that contribute to cancer progression. Hence, gaining insights into the intrinsic signal transduction of tumors and the signaling communication between tumor cells and various matrix components within the tumor microenvironment may reveal novel therapeutic targets. In this review, we initially examine the development of the tumor microenvironment. Subsequently, we delineate the oncogenic signaling pathways within tumor cells and elucidate the reciprocal communication between these pathways and the tumor microenvironment. Finally, we give an overview of the effect of signal transduction within the tumor microenvironment on tumor metabolism and tumor immunity.
Subject(s)
Neoplasms , Signal Transduction , Tumor Microenvironment , Humans , Neoplasms/metabolism , Neoplasms/pathology , Animals , Epithelial-Mesenchymal TransitionABSTRACT
Alternative polyadenylation plays an important role in cancer initiation and progression; however, current transcriptome-wide association studies mostly ignore alternative polyadenylation when identifying putative cancer susceptibility genes. Here, we perform a pan-cancer 3' untranslated region alternative polyadenylation transcriptome-wide association analysis by integrating 55 well-powered (n > 50,000) genome-wide association studies datasets across 22 major cancer types with alternative polyadenylation quantification from 23,955 RNA sequencing samples across 7,574 individuals. We find that genetic variants associated with alternative polyadenylation are co-localized with 28.57% of cancer loci and contribute a significant portion of cancer heritability. We further identify 642 significant cancer susceptibility genes predicted to modulate cancer risk via alternative polyadenylation, 62.46% of which have been overlooked by traditional expression- and splicing- studies. As proof of principle validation, we show that alternative alleles facilitate 3' untranslated region lengthening of CRLS1 gene leading to increased protein abundance and promoted proliferation of breast cancer cells. Together, our study highlights the significant role of alternative polyadenylation in discovering new cancer susceptibility genes and provides a strong foundational framework for enhancing our understanding of the etiology underlying human cancers.
Subject(s)
Neoplasms , Transcriptome , Humans , Polyadenylation/genetics , Genome-Wide Association Study , 3' Untranslated Regions/genetics , Gene Expression Profiling , Neoplasms/geneticsABSTRACT
Natural gas distributed energy is recognized as a pivotal means to enhance energy efficiency and mitigate carbon dioxide emissions through localized energy cascading. Positioned as a key option for advancing the Sustainable Development Goals, this system optimizes energy utilization near end-users. While maximizing energy efficiency, it is imperative to address potential environmental challenges. A thorough, comprehensive environmental assessment, facilitated by the life cycle assessment method, proves instrumental in meeting this standard. Employing this method enables an intuitive grasp of the environmental strengths and weaknesses inherent in natural gas distributed energy within the power structure. This insight serves as a foundation for informed project decision-making, fostering the growth of the industry. We selected six environmental impact assessment categories based on the CML 2001 method, and conducted the life cycle analysis across four stages. China's inaugural natural gas distributed energy demonstration project was chosen as a model case, and an environmental impact assessment inventory was established, utilizing survey data and literature for comprehensive data collection and analysis. Results from case testing yield environmental impact assessment outcomes, with a specific sensitivity analysis for stages with notable environmental impact factors. The study underscores that the operation phase has the highest environmental impact, comprising 78.37% of the total combined environmental impact, followed by the fuel production phase. Comparative analyses with coal-fired and conventional natural gas power generation, based on dimensionless literature data, reveal that abiotic resources depletion potential is the primary contributor to the environmental impact of 1 kWh of electricity product, constituting 52.76% of the total impact value, followed by global warming potential. Concrete strategies have been outlined for decision-making in both the operational and planning phases of natural gas distributed energy projects. The strengthening of policies is pinpointed towards grid connection and scale expansion.
ABSTRACT
BACKGROUND: The 5´ untranslated region (5´ UTR) plays a key role in regulating translation efficiency and mRNA stability, making it a favored target in genetic engineering and synthetic biology. A common feature found in the 5´ UTR is the poly-adenine (poly(A)) tract. However, the effect of 5´ UTR poly(A) on protein production remains controversial. Machine-learning models are powerful tools for explaining the complex contributions of features, but models incorporating features of 5´ UTR poly(A) are currently lacking. Thus, our goal is to construct such a model, using natural 5´ UTRs from Kluyveromyces marxianus, a promising cell factory for producing heterologous proteins. RESULTS: We constructed a mini-library consisting of 207 5´ UTRs harboring poly(A) and 34 5´ UTRs without poly(A) from K. marxianus. The effects of each 5´ UTR on the production of a GFP reporter were evaluated individually in vivo, and the resulting protein abundance spanned an approximately 450-fold range throughout. The data were used to train a multi-layer perceptron neural network (MLP-NN) model that incorporated the length and position of poly(A) as features. The model exhibited good performance in predicting protein abundance (average R2 = 0.7290). The model suggests that the length of poly(A) is negatively correlated with protein production, whereas poly(A) located between 10 and 30 nt upstream of the start codon (AUG) exhibits a weak positive effect on protein abundance. Using the model as guidance, the deletion or reduction of poly(A) upstream of 30 nt preceding AUG tended to improve the production of GFP and a feruloyl esterase. Deletions of poly(A) showed inconsistent effects on mRNA levels, suggesting that poly(A) represses protein production either with or without reducing mRNA levels. CONCLUSION: The effects of poly(A) on protein production depend on its length and position. Integrating poly(A) features into machine-learning models improves simulation accuracy. Deleting or reducing poly(A) upstream of 30 nt preceding AUG tends to enhance protein production. This optimization strategy can be applied to enhance the yield of K. marxianus and other microbial cell factories.
Subject(s)
Kluyveromyces , 5' Untranslated Regions , Base Sequence , Kluyveromyces/genetics , Kluyveromyces/metabolism , RNA, Messenger/geneticsABSTRACT
Alternative splicing can produce transcripts that affect cancer development and thus shows potential for cancer diagnosis and treatment. However, intron retention (IR), a type of alternative splicing, has been studied less in cancer biology research. Here, we generated a pan-cancer IR landscape for more than 10,000 samples across 33 cancer types from The Cancer Genome Atlas (TCGA). We characterized differentially retained introns between tumor and normal samples and identified retained introns associated with survival. We discovered 988 differentially retained introns in 14 cancers, some of which demonstrated diagnostic potential in multiple cancer types. We also inferred a large number of prognosis-related introns in 33 cancer types, and the associated genes included well-known cancer hallmarks such as angiogenesis, metastasis, and DNA mutations. Notably, we discovered a novel intron retention inside the 5'UTR of STN1 that is associated with the survival of lung cancer patients. The retained intron reduces translation efficiency by producing upstream open reading frames (uORFs) and thereby inhibits colony formation and cell migration of lung cancer cells. Besides, the IR-based prognostic model achieved good stratification in certain cancers, as illustrated in acute myeloid leukemia. Taken together, we performed a comprehensive IR survey at a pan-cancer level, and the results implied that IR has the potential to be diagnostic and prognostic cancer biomarkers, as well as new drug targets.
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The occurrence and development of tumors require the metabolic reprogramming of cancer cells, namely the alteration of flux in an autonomous manner via various metabolic pathways to meet increased bioenergetic and biosynthetic demands. Tumor cells consume large quantities of nutrients and produce related metabolites via their metabolism; this leads to the remodeling of the tumor microenvironment (TME) to better support tumor growth. During TME remodeling, the immune cell metabolism and antitumor immune activity are affected. This further leads to the escape of tumor cells from immune surveillance and therefore to abnormal proliferation. This review summarizes the regulatory functions associated with the abnormal biosynthesis and activity of metabolic signaling molecules during the process of tumor metabolic reprogramming. In addition, we provide a comprehensive description of the competition between immune cells and tumor cells for nutrients in the TME, as well as the metabolites required for tumor metabolism, the metabolic signaling pathways involved, and the functionality of the immune cells. Finally, we summarize current research targeted at the development of tumor immunotherapy. We aim to provide new concepts for future investigations of the mechanisms underlying the metabolic reprogramming of tumors and explore the association of these mechanisms with tumor immunity.
Subject(s)
Metabolic Reprogramming , Neoplasms , Humans , Signal Transduction , Immunologic Surveillance , Immunotherapy , Tumor MicroenvironmentABSTRACT
Salmonella, a Gram-negative bacterium that infects humans and animals, causes diseases ranging from gastroenteritis to severe systemic infections. Here, we discuss various strategies used by Salmonella against host cell defenses. Epithelial cell invasion largely depends on a Salmonella pathogenicity island (SPI)-1-encoded type 3 secretion system, a molecular syringe for injecting effector proteins directly into host cells. The internalization of Salmonella into macrophages is primarily driven by phagocytosis. After entering the host cell cytoplasm, Salmonella releases many effectors to achieve intracellular survival and replication using several secretion systems, primarily an SPI-2-encoded type 3 secretion system. Salmonella-containing vacuoles protect Salmonella from contacting bactericidal substances in epithelial cells and macrophages. Salmonella modulates the immunity, metabolism, cell cycle, and viability of host cells to expand its survival in the host, and the intracellular environment of Salmonella-infected cells promotes its virulence. This review provides insights into how Salmonella subverts host cell defenses for survival.
Subject(s)
Salmonella enterica , Type III Secretion Systems , Animals , Humans , Type III Secretion Systems/genetics , Type III Secretion Systems/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Salmonella typhimurium/metabolism , Salmonella enterica/metabolism , VirulenceABSTRACT
Myocardial infarction (MI) is a leading cause of heart failure (HF), associated with morbidity and mortality worldwide. As an essential part of gene expression regulation, the role of alternative polyadenylation (APA) in post-MI HF remains elusive. Here, we revealed a global, APA-mediated, 3' untranslated region (3' UTR)-lengthening pattern in both human and murine post-MI HF samples. Furthermore, the 3' UTR of apoptotic repressor gene, AVEN, is lengthened after MI, contributing to its downregulation. AVEN knockdown increased cardiomyocyte apoptosis, whereas restoration of AVEN expression substantially improved cardiac function. Mechanistically, AVEN 3' UTR lengthening provides additional binding sites for miR-30b-5p and miR-30c-5p, thus reducing AVEN expression. Additionally, PABPN1 (poly(A)-binding protein 1) was identified as a potential regulator of AVEN 3' UTR lengthening after MI. Altogether, our findings revealed APA as a unique mechanism regulating cardiac injury in response to MI and also indicated that the APA-regulated gene, AVEN, holds great potential as a critical therapeutic target for treating post-MI HF.
Subject(s)
Heart Injuries , MicroRNAs , Myocardial Infarction , Animals , Humans , Mice , 3' Untranslated Regions/genetics , Adaptor Proteins, Signal Transducing/metabolism , Apoptosis/genetics , Apoptosis Regulatory Proteins/metabolism , Down-Regulation , Heart Injuries/genetics , Membrane Proteins/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Myocytes, Cardiac/metabolism , Poly(A)-Binding Protein IABSTRACT
Single-cell RNA sequencing (scRNA-seq) has emerged as a powerful tool for uncovering cellular heterogeneity. However, the high costs associated with this technique have rendered it impractical for studying large patient cohorts. We introduce ENIGMA (Deconvolution based on Regularized Matrix Completion), a method that addresses this limitation through accurately deconvoluting bulk tissue RNA-seq data into a readout with cell-type resolution by leveraging information from scRNA-seq data. By employing a matrix completion strategy, ENIGMA minimizes the distance between the mixture transcriptome obtained with bulk sequencing and a weighted combination of cell-type-specific expression. This allows the quantification of cell-type proportions and reconstruction of cell-type-specific transcriptomes. To validate its performance, ENIGMA was tested on both simulated and real datasets, including disease-related tissues, demonstrating its ability in uncovering novel biological insights.
Subject(s)
Gene Expression Profiling , Transcriptome , Humans , Gene Expression Profiling/methods , Software , RNA-Seq/methods , Sequence Analysis, RNA/methodsABSTRACT
Recently, the International Energy Agency (IEA) released a comprehensive roadmap for the global energy sector to achieve net-zero emission by 2050. Considering the sizeable share of (Sub-Sahara) Africa in the global population, the attainment of global energy sector net-zero emission is practically impossible without a commitment from African countries. Therefore, it is important to study and analyze feasible/sustainable ways to solve the energy/electricity poverty in Africa. In this paper, the energy poverty in Africa and the high renewable energy (RE) potential are reviewed. Beyond this, the generation of electricity from the abundant RE potential in this region is analyzed in hourly timestep. This study is novel as it proposes a Sub-Sahara Africa (SSA) central grid as one of the fastest/feasible solutions to the energy poverty problem in this region. The integration of a sizeable share of electric vehicles with the proposed central grid is also analyzed. This study aims to determine the RE electricity generation capacities, economic costs, and supply strategies required to balance the projected future electricity demand in SSA. The analysis presented in this study is done considering 2030 and 2040 as the targeted years of implementation. EnergyPLAN simulation program is used to simulate/analyze the generation of electricity for the central grid. The review of the energy poverty in SSA showed that the electricity access of all the countries in this region is less than 100%. The analysis of the proposed central RE grid system is a viable and sustainable option, however, it requires strategic financial planning for its implementation. The cheapest investment cost from all the case scenarios in this study is $298 billion. Considering the use of a single RE technology, wind power systems implementation by 2030 and 2040 are the most feasible options as they have the least economic costs. Overall, the integration of the existing/fossil-fueled power systems with RE technologies for the proposed central grid will be the cheapest/easiest pathway as it requires the least economic costs. While this does not require the integration of storage systems, it will help the SSA countries reduce their electricity sector carbon emission by 56.6% and 61.8% by 2030 and 2040 respectively.
ABSTRACT
BACKGROUND: Immune checkpoint inhibitors (ICIs) shed new light on triple-negative breast cancer (TNBC), but only a minority of patients demonstrate response. Therefore, adaptive immune resistance (AIR) needs to be further defined to guide the development of ICI regimens. METHODS: Databases, including The Cancer Genome Atlas, Gene Ontology Resource, University of California Santa Cruz Genome Browser, and Pubmed, were used to screen epigenetic modulators, regulators for CD8+ T cells, and transcriptional regulators of programmed cell death-ligand 1 (PD-L1). Human peripheral blood mononuclear cell (Hu-PBMC) reconstruction mice were adopted for xenograft transplantation. Tumor specimens from a TNBC cohort and the clinical trial CTR20191353 were retrospectively analyzed. RNA-sequencing, Western blotting, qPCR and immunohistochemistry were used to assess gene expression. Coculture assays were performed to evaluate the regulation of TNBC cells on T cells. Chromatin immunoprecipitation and transposase-accessible chromatin sequencing were used to determine chromatin-binding and accessibility. RESULTS: The epigenetic modulator AT-rich interaction domain 1A (ARID1A) gene demonstrated the highest expression association with AIR relative to other epigenetic modulators in TNBC patients. Low ARID1A expression in TNBC, causing an immunosuppressive microenvironment, promoted AIR and inhibited CD8+ T cell infiltration and activity through upregulating PD-L1. However, ARID1A did not directly regulate PD-L1 expression. We found that ARID1A directly bound the promoter of nucleophosmin 1 (NPM1) and that low ARID1A expression increased NPM1 chromatin accessibility as well as gene expression, further activating PD-L1 transcription. In Hu-PBMC mice, atezolizumab demonstrated the potential to reverse ARID1A deficiency-induced AIR in TNBC by reducing tumor malignancy and activating anti-tumor immunity. In CTR20191353, ARID1A-low patients derived more benefit from pucotenlimab compared to ARID1A-high patients. CONCLUSIONS: In AIR epigenetics, low ARID1A expression in TNBC contributed to AIR via the ARID1A/NPM1/PD-L1 axis, leading to poor outcome but sensitivity to ICI treatment.
Subject(s)
Immune Checkpoint Inhibitors , Triple Negative Breast Neoplasms , Humans , Animals , Mice , Immune Checkpoint Inhibitors/pharmacology , Immune Checkpoint Inhibitors/therapeutic use , CD8-Positive T-Lymphocytes/metabolism , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/pathology , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/pathology , B7-H1 Antigen , Retrospective Studies , Nuclear Proteins , Tumor Microenvironment/genetics , DNA-Binding Proteins , Transcription FactorsABSTRACT
BACKGROUND: As a chronic mountain sickness(CMS) with the highest incidence and the greatest harm, the pathogenesis of high altitude polycythemia (HAPC) is still not fully understood. METHODS: 37 HAPC patients and 42 healthy subjects were selected from plateau, and peripheral venous blood samples were collected for transcriptome sequencing on Illumina NovaSeq platform. The sequenced data were analyzed by bioinformatics and phenotypic association analysis. RESULTS: The results showed significant differences in multiple clinical indicators including RBC and HGB et al. existed between HAPC and control. Based on the RNA-seq data, 550 genes with significant differential expression were identified in HAPC patients. GO and KEGG pathway enrichment analysis showed that the up-regulated genes were mainly enriched in processes such as erythrocyte differentiation and development and homeostasis of number of cells, while the down-regulated genes were mainly enriched in categories such as immunoglobulin production, classical pathway of complement activation and other biological processes. The coupling analysis of differential expression genes(DEGs) and pathological phenotypes revealed that 91 DEGs were in close correlation with in the phenotype of red blood cell volume distribution (width-CV and width-SD), and they were all up-regulated in HAPC and involved in the process of erythrocyte metabolism. Combined with the functional annotation of DEGs and literature survey, we found that the expression of several potential genes might be responsible for pathogenesis of HAPC. Besides, cell type deconvolution analysis result suggested that the changes in the number of some immune cell types was significantly lower in HAPC patients than control, implying the autoimmune level of HAPC patients was affected to a certain extent. CONCLUSION: This study provides an important data source for understanding the pathogenesis and screening pathogenic genes of HAPC. We found for the first time that there was a significant correlation between HAPC and the pathological phenotype of width-CV and width-SD, wherein the enriched genes were all up-regulated expressed and involved in the process of erythrocyte metabolism. Although the role of these genes needs to be further studied, the candidate genes can provide a starting point for functionally pinning down the underlying mechanism of HAPC.
Subject(s)
Altitude Sickness , Polycythemia , Humans , Altitude Sickness/genetics , Altitude Sickness/complications , Altitude , Polycythemia/genetics , Polycythemia/complications , Erythrocytes/metabolismABSTRACT
HMG protein Tox4 is a regulator of PP1 phosphatases with unknown function in development. Here we show that Tox4 conditional knockout in mice reduces thymic cellularity, partially blocks T cell development, and decreases ratio of CD8 to CD4 through decreasing proliferation and increasing apoptosis of CD8 cells. In addition, single-cell RNA-seq discovered that Tox4 loss also impairs proliferation of the fast-proliferating double positive (DP) blast population within DP cells in part due to downregulation of genes critical for proliferation, notably Cdk1. Moreover, genes with high and low expression level are more dependent on Tox4 than genes with medium expression level. Mechanistically, Tox4 may facilitate transcriptional reinitiation and restrict elongation in a dephosphorylation-dependent manner, a mechanism that is conserved between mouse and human. These results provide insights into the role of TOX4 in development and establish it as an evolutionarily conserved regulator of transcriptional elongation and reinitiation.
Subject(s)
CD8-Positive T-Lymphocytes , Thymus Gland , Animals , Mice , Humans , Cell Differentiation/geneticsABSTRACT
By investigating the contamination status and predicting the exposure risk of mycotoxin in Coicis Semen, we aim to provide guidance for the safety supervision of Chinese medicinal materials and the formulation(revision) of mycotoxin limit standards. The content of 14 mycotoxins in the 100 Coicis Semen samples collected from five major markets of Chinese medicinal materials in China was determined by UPLC-MS/MS. The probability evaluation model based on Monte Carlo simulation method was established after Chi-square test and One-way ANOVA of the sample contamination data. Health risk assessment was performed on the basis of margin of exposure(MOE) and margin of safety(MOS). The results showed that zearalenone(ZEN), aflatoxin B_1(AFB_1), deoxynivalenol(DON), sterigmatocystin(ST), and aflatoxin B_2(AFB_2) in the Coicis Semen samples had the detection rates of 84%, 75%, 36%, 19%, and 18%, and the mean contamination levels of 117.42, 4.78, 61.16, 6.61, and 2.13 µg·kg~(-1), respectively. According to the limit standards in the Chinese Pharmacopoeia(2020 edition), AFB_1, AFs and ZEN exceeded the standards to certain extents, with the over-standard rates of 12.0%, 9.0%, and 6.0%, respectively. The exposure risks of Coicis Semen to AFB_1, AFB2, ST, DON, and ZEN were low, while 86% of the samples were contaminated with two or more toxins, which needs more attention. It is suggested that the research on the combined toxicity of different mycotoxins should be strengthened to accelerate the cumulative exposure assessment of mixed contaminations and the formulation(revision) of toxin limit standards.