Identifying and characterizing drug sensitivity-related lncRNA-TF-gene regulatory triplets.

Recently, many studies have shown that lncRNA can mediate the regulation of TF-gene in drug sensitivity. However, there is still a lack of systematic identification of lncRNA-TF-gene regulatory triplets for drug sensitivity. In this study, we propose a novel analytic approach to systematically identify the lncRNA-TF-gene regulatory triplets related to the drug sensitivity by integrating transcriptome data and drug sensitivity data. Totally, 1570 drug sensitivity-related lncRNA-TF-gene triplets were identified, and 16 307 relationships were formed between drugs and triplets. Then, a comprehensive characterization was performed. Drug sensitivity-related triplets affect a variety of biological functions including drug response-related pathways. Phenotypic similarity analysis showed that the drugs with many shared triplets had high similarity in their two-dimensional structures and indications. In addition, Network analysis revealed the diverse regulation mechanism of lncRNAs in different drugs. Also, survival analysis indicated that lncRNA-TF-gene triplets related to the drug sensitivity could be candidate prognostic biomarkers for clinical applications. Next, using the random walk algorithm, the results of which we screen therapeutic drugs for patients across three cancer types showed high accuracy in the drug-cell line heterogeneity network based on the identified triplets. Besides, we developed a user-friendly web interface-DrugSETs (http://bio-bigdata.hrbmu.edu.cn/DrugSETs/) available to explore 1570 lncRNA-TF-gene triplets relevant with 282 drugs. It can also submit a patient's expression profile to predict therapeutic drugs conveniently. In summary, our research may promote the study of lncRNAs in the drug resistance mechanism and improve the effectiveness of treatment.

DEC1 is involved in circadian rhythm disruption-exacerbated pulmonary fibrosis.

BACKGROUND: The alveolar epithelial type II cell (AT2) and its senescence play a pivotal role in alveolar damage and pulmonary fibrosis. Cell circadian rhythm is strongly associated with cell senescence. Differentiated embryonic chondrocyte expressed gene 1 (DEC1) is a very important circadian clock gene. However, the role of DEC1 in AT2 senescence and pulmonary fibrosis was still unclear. RESULTS: In this study, a circadian disruption model of light intervention was used. It was found that circadian disruption exacerbated pulmonary fibrosis in mice. To understand the underlying mechanism, DEC1 levels were investigated. Results showed that DEC1 levels increased in lung tissues of IPF patients and in bleomycin-induced mouse fibrotic lungs. In vitro study revealed that bleomycin and TGF-ß1 increased the expressions of DEC1, collagen-I, and fibronectin in AT2 cells. Inhibition of DEC1 mitigated bleomycin-induced fibrotic changes in vitro and in vivo. After that, cell senescence was observed in bleomycin-treated AT2 cells and mouse models, but these were prevented by DEC1 inhibition. At last, p21 was confirmed having circadian rhythm followed DEC1 in normal conditions. But bleomycin disrupted the circadian rhythm and increased DEC1 which promoted p21 expression, increased p21 mediated AT2 senescence and pulmonary fibrosis. CONCLUSIONS: Taken together, circadian clock protein DEC1 mediated pulmonary fibrosis via p21 and cell senescence in alveolar epithelial type II cells.

BMAL1/p53 mediating bronchial epithelial cell autophagy contributes to PM2.5-aggravated asthma.

BACKGROUND: Fine particulate matter (PM2.5) is associated with increased incidence and severity of asthma. PM2.5 exposure disrupts airway epithelial cells, which elicits and sustains PM2.5-induced airway inflammation and remodeling. However, the mechanisms underlying development and exacerbation of PM2.5-induced asthma were still poorly understood. The aryl hydrocarbon receptor nuclear translocator-like protein 1 (BMAL1) is a major circadian clock transcriptional activator that is also extensively expressed in peripheral tissues and plays a crucial role in organ and tissue metabolism. RESULTS: In this study, we found PM2.5 aggravated airway remodeling in mouse chronic asthma, and exacerbated asthma manifestation in mouse acute asthma. Next, low BMAL1 expression was found to be crucial for airway remodeling in PM2.5-challenged asthmatic mice. Subsequently, we confirmed that BMAL1 could bind and promote ubiquitination of p53, which can regulate p53 degradation and block its increase under normal conditions. However, PM2.5-induced BMAL1 inhibition resulted in up-regulation of p53 protein in bronchial epithelial cells, then increased-p53 promoted autophagy. Autophagy in bronchial epithelial cells mediated collagen-I synthesis as well as airway remodeling in asthma. CONCLUSIONS: Taken together, our results suggest that BMAL1/p53-mediated bronchial epithelial cell autophagy contributes to PM2.5-aggravated asthma. This study highlights the functional importance of BMAL1-dependent p53 regulation during asthma, and provides a novel mechanistic insight into the therapeutic mechanisms of BMAL1. Video Abstract.

GPRASP1 is a candidate anti-oncogene and correlates with immune microenvironment and immunotherapeutic efficiency in head and neck cancer.

BACKGROUND: G-protein-coupled receptor-associated sorting protein 1 (GPRASP1) plays an important role in tumorigenesis. However, GPRASP1 specific role has not been clarified in head and neck cancer (HNC). METHODS: HNC RNA sequencing (RNA-seq) datasets, DNA methylation data, somatic mutation data, copy number variation (CNV) data, and corresponding clinicopathologic information were acquired from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. A comprehensive evaluation was performed to explore the relationship of GPRASP1 expression with clinicopathologic characteristics, CNV, and DNA methylation. Additionally, we employed HNC tissue microarray (TMA) to further confirm the relation between GPRASP1 expression and clinical features. Then, we systematically associated the GPRASP1 with immunological properties from numerous perspectives, such as immune cell infiltration, immune-related pathways, immune checkpoint inhibitors (ICIs), immunomodulators, immunogenicity, and immunotherapy. RESULTS: Analyzing TCGA, GEO, and TMA datasets, GPRASP1 is significantly down-regulated in HNC compared to normal tissues. The expression of GPRASP1 is significantly negatively correlated with clinical features (perineural invasion, histologic grade, T stage, and TNM stage), and is an independent predictor of favorable prognosis, regardless of other clinicopathological features (HR: 0.42, 95% CI 0.20-0.91, p = 0.028). The etiological investigation found that the abnormal expression of GPRASP1 was related to DNA methylation, not CMV. Subsequently, the high expression of GPRASP1 was significantly correlated with immune cell infiltration (CD8+  T cell, tumor infiltrating lymphocyte), immune-related pathways (cytolytic activity, check-point, human leukocyte antigen), ICIs (CTLA4, HAVCR2, LAG3, PDCD1, and TIGIT), immunomodulators (CCR4/5, CXCL9, CXCR3/4/5), and immunogenicity (immune score, neoantigen, tumor mutation burden). Finally, immunophenoscore and tumor immune dysfunction and exclusion analysis demonstrated that GPRASP1 expression levels can accurately predict the immunotherapeutic response. CONCLUSION: GPRASP1 is a promising candidate biomarker that plays a role in the occurrence, development, and prognosis of HNC. Evaluating GPRASP1 expression will aid in the characterization of tumor microenvironment infiltration and orient more efficient immunotherapy strategies.

Bleomycin induced apical-basal polarity loss in alveolar epithelial cell contributes to experimental pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a fatal fibrosing interstitial lung disease with limited therapeutic options and a median survival of 3 years after diagnosis. Dysregulated epithelial regeneration is key event involved in initiating and sustaining IPF. The type II alveolar epithelial cells (AECIIs) play a crucial role for epithelial regeneration and stabilisation of alveoli. Loss of cell apical-basal polarity contributes to fibrosis. AECII has apical-basal polarity, but it is poorly understood whether AECII apical-basal polarity loss is involved in fibrosis. Bleomycin is a traditional inducer of pulmonary fibrosis. Here firstly we observed that bleomycin induced apical-basal polarity loss in cultured AECIIs. Next, cell polarity proteins lethal (2) giant larvae 1 (Lgl1), PAR-3A, aPKC and PAR-6B were investigated. We found bleomycin induced increases of Lgl1 protein and decreases of PAR-3A protein, and bleomycin-induced PAR-3A depression was mediated by increased-Lgl1. Then Lgl1 siRNA was transfected into AECIIs. Lgl1 siRNA prevented apical-basal polarity loss in bleomycin-treated AECIIs. At last, Lgl1-conditional knockout mice were applied in making animal models. Bleomycin induced pulmonary fibrosis, but this was attenuated in Lgl1-conditional knockout mice. Together, these data indicated that bleomycin mediated AECII apical-basal polarity loss which contributed to experimental pulmonary fibrosis. Inhibition of Lgl1 should be a potential therapeutic strategy for the disease.

Preparation of FA-targeted magnetic nanocomposites co-loading TFPI-2 plasmid and cis-platinum and its targeted therapy effects on nasopharyngeal carcinoma.

The majority of patients diagnosed with nasopharyngeal carcinoma (NPC) present with advanced-stage disease. The main treatment for these patients is concurrent chemoradiotherapy, which has various side effects. To improve the therapeutic effects and reduce the side effects of NPC chemoradiotherapy, we constructed a multifunctional folic acid (FA)-targeted magnetic nanocomposite codelivering tissue factor pathway inhibitor-2 (TFPI-2) and cisplatin (CDDP). This novel nanocomposite (FA-MNP/CDDP/TFPI-2) was obtained by amidation and electrostatic adsorption between FA-methoxypolyethylene glycol-polyethyleneimine (FA-MPEG-PEI) containing the TFPI-2 plasmid and magnetic nanoparticles modified by aldehyde sodium alginate loaded with CDDP. Transmission electron microscopy (TEM) images showed that the size of the individual magnetite particle core was approximately 11.5 nm. The structure and composition of the nanocomposites were identified and examined by 1H nuclear magnetic resonance (NMR) spectroscopy and ultraviolet (UV) spectrophotometry. The fluorescence analysis, Prussian blue iron staining, magnetic resonance (MR) imaging and whole-body fluorescence imaging results demonstrated that FA-MNP/CDDP/TFPI-2 showed high gene transfection efficiency and could target tumor cells via folate receptor (FR)-mediated delivery. The codelivery analysis showed that the obtained FA-MNP/CDDP/TFPI-2 composite could cause significantly more apoptosis than treatment with CDDP or TFPI-2 alone. The results showed that the FA-MNP/CDDP/TFPI-2 composites were successfully synthesized and indicated to be a specific molecular target for the FR with significant inhibitory effects on the growth of HNE-1 cells.

Overexpression of a wheat phospholipase D gene, TaPLDα, enhances tolerance to drought and osmotic stress in Arabidopsis thaliana.

Phospholipase D (PLD) is crucial for plant responses to stress and signal transduction, however, the regulatory mechanism of PLD in abiotic stress is not completely understood; especially, in crops. In this study, we isolated a gene, TaPLDα, from common wheat (Triticum aestivum L.). Analysis of the amino acid sequence of TaPLDα revealed a highly conserved C2 domain and two characteristic HKD motifs, which is similar to other known PLD family genes. Further characterization revealed that TaPLDα expressed differentially in various organs, such as roots, stems, leaves and spikelets of wheat. After treatment with abscisic acid (ABA), methyl jasmonate, dehydration, polyethylene glycol and NaCl, the expression of TaPLDα was up-regulated in shoots. Subsequently, we generated TaPLDα-overexpressing transgenic Arabidopsis lines under the control of the dexamethasone-inducible 35S promoter. The overexpression of TaPLDα in Arabidopsis resulted in significantly enhanced tolerance to drought, as shown by reduced chlorosis and leaf water loss, higher relative water content and lower relative electrolyte leakage than the wild type. Moreover, the TaPLDα-overexpressing plants exhibited longer roots in response to mannitol treatment. In addition, the seeds of TaPLDα-overexpressing plants showed hypersensitivity to ABA and osmotic stress. Under dehydration, the expression of several stress-related genes, RD29A, RD29B, KIN1 and RAB18, was up-regulated to a higher level in TaPLDα-overexpressing plants than in wild type. Taken together, our results indicated that TaPLDα can enhance tolerance to drought and osmotic stress in Arabidopsis and represents a potential candidate gene to enhance stress tolerance in crops.

Targeted delivery of cisplatin magnetic nanoparticles for diagnosis and treatment of nasopharyngeal carcinoma.

Rapid advances in nanotechnology are paving the way for innovative breakthroughs in overcoming the current limitations in the clinical treatment of cancer and other prevalent diseases plaguing mankind. Magnetic nanoparticles composed of iron oxide (Fe3O4) are a novel class of nanoparticles that are receiving increasing attention in the field of cancer therapy. To address the inherent limitations, bare Fe3O4 can be functionalized, polymerized, assembled, or combined with other functional materials to produce a range of smart nanoplatforms suitable for tumor therapy. In this paper, we present a unique multifunctional therapeutic nanoplatform centered on aldehyde-oxidized sodium alginate-stabilized iron oxide nanoparticles (NPs) designed for T2-weighted magnetic resonance (MR) imaging. Sodium alginate oxide and ferric oxide nanoparticles were prepared respectively, and the two particles were mixed in a certain molar ratio to form a complex, which was coupled to target polypeptide GE11 by Schiff base reaction, and finally supported by cisplatin through coordination complexation. The prepared magnetic nanoparticles (hereinafter referred to as GE11-CDDP-ASA@Fe3O4) have an average diameter of 152.9 nm, and have good colloidal stability and cytocompatibility. The distinctive structure and composition of GE11-CDDP-ASA@Fe3O4 contribute to its excellent MRI imaging performance, positioning it as a nano platform suitable for enhancing the efficacy of combination therapy in tumor treatment. This is of great significance for translational nanomedicine applications.

Epigenetically upregulated NSUN2 confers ferroptosis resistance in endometrial cancer via m5C modification of SLC7A11 mRNA.

Endometrial cancer (EC) is a prevalent gynecological malignancy worldwide, and 5-methylcytosine (m5C) modification of mRNA is a crucial epigenetic modification associated with the development and occurrence of several cancers. However, the precise function of m5C modification in EC remains elusive. This study aimed to investigate the expression and clinical significance of the primary m5C modification writer, NSUN2, in EC. Our findings indicated that NSUN2 exhibited a substantial up-regulation in EC as a result of an epigenetic augmentation in H3K4me3 levels within the promoter region, which was triggered by the down-regulation of KDM5A. Moreover, gain- and loss-of-function experiments revealed the role of NSUN2 in enhancing m5C modification of mRNA, thereby promoting EC cell proliferation. RNA bisulfite sequencing and transcriptomic sequencing were employed to elucidate the involvement of NSUN2 in the regulation of ferroptosis. Subsequent in vitro experiments confirmed that the knockdown of NSUN2 significantly up-regulated the levels of lipid peroxides and lipid ROS in EC cells, thereby augmenting the susceptibility of EC to ferroptosis. Mechanistically, NSUN2 stimulated the m5C modification of SLC7A11 mRNA, and the m5C reader YBX1 exhibited direct recognition and binding to the m5C sites on SLC7A11 mRNA via its internal cold shock domain (CSD), leading to an increase in SLC7A11 mRNA stability and elevated levels of SLC7A11. Additionally, rescue experiments showed that NSUN2 functioned as a suppressor of ferroptosis, which was dependent on SLC7A11. Overall, targeting the NSUN2/SLC7A11 axis inhibited tumor growth by increasing lipid peroxidation and ferroptosis of EC cells both in vitro and in vivo. Therefore, our study provides new insight into the role of NSUN2, suggesting that NSUN2 may serve as a prognostic biomarker and therapeutic target in patients with EC.

METTL3 regulates M6A methylation-modified EBV-pri-miR-BART3-3p to promote NK/T cell lymphoma growth.

OBJECTIVE: N6-methyladenosine (M6A) is the most prevalent epigenetic alteration. Methyltransferase-like 3 (METTL3) is a key player in the control of M6A modification. Methyltransferase promote the processing of mature miRNA in an M6A-dependent manner, thereby participating in disease occurrence and development. However, the regulatory mechanism of M6A in NK/T cell lymphoma (NKTCL) remains unclear. PATIENTS AND METHODS: We determined the expression of METTL3 and its correlation with clinicopathological features using qRT-PCR and immunohistochemistry. We evaluated the effects of METTL3 on NKTCL cells using dot blot assay, CCK8 assay and subcutaneous xenograft experiment. We then applied M6A sequencing combined with gene expression omnibus data to screen candidate targets of METTL3. Finally, we investigated the regulatory mechanism of METTL3 in NKTCL by methylated RNA immunoprecipitation and RNA immunoprecipitation (RIP) assays. RESULTS: We demonstrated that METTL3 was highly expressed in NKTCL cells and tissues and indicated poor prognosis. The METTL3 expression was associated with NKTCL survival. Functionally, METTL3 promoted the proliferation capability of NKTCL cells in vitro and in vivo. Furthermore, EBV-miR-BART3-3p was identified as the downstream effector of METTL3, and silencing EBV-miR-BART3-3p inhibited the proliferation of NKTCL. Finally, we confirmed that PLCG2 as a target gene of EBVmiR-BART3-3p by relative assays. CONCLUSIONS: We identified that METTL3 is significantly up-regulated in NKTCL and promotes NKTCL development. M6A modification contributes to the progression of NKTCL via the METTL3/EBV-miR-BART3-3p/PLCG2 axis. Our study is the first to report that M6A methylation has a critical role in NKTCL oncogenesis, and could be a potential target for NKTCL treatment.

PM2.5 exposure-induced senescence-associated secretory phenotype in airway smooth muscle cells contributes to airway remodeling.

Fine particulate matter (PM2.5) has been linked to increased severity and incidence of airway diseases, especially chronic obstructive pulmonary disease (COPD) and asthma. Airway remodeling is an important event in both COPD and asthma, and airway smooth muscle cells (ASMCs) are key cells which directly involved in airway remodeling. However, it was unclear how PM2.5 affected ASMCs. This study investigates the effects of PM2.5 on airway smooth muscle and its mechanism. We first showed that inhaled particulate matter was distributed in the airway smooth muscle bundle, combined with increased airway smooth muscle bundle and collagen deposition in vivo. Then, we demonstrated that PM2.5 induced up-regulation of collagen-I and alpha-smooth muscle actin (α-SMA) expression in rat and human ASMCs in vitro. Next, we found PM2.5 led to rat and human ASMCs senescence and exhibited senescence-associated secretory phenotype (SASP) by autophagy-induced GATA4/TRAF6/NF-κB signaling, which contributed to collagen-I and α-SMA synthesis as well as airway smooth muscle remodeling. Together, our results provided evidence that SASP induced by PM2.5 in airway smooth muscle cells prompted airway remodeling.

Research on the Vitality Evaluation of Parks and Squares in Medium-Sized Chinese Cities from the Perspective of Urban Functional Areas.

Medium-sized cities are increasingly committed to the planning and construction of urban public spaces to meet people's demand for high-quality urban life. Parks and squares are important parts of urban public spaces, and their vitality represents the quality of public spaces to a certain extent and reflects the happiness index of urban residents. At present, the functional areas and transportation networks of medium-sized cities are still developing. Due to the influence of urban construction, the planning of parks and squares in medium-sized cities has not yet caught up to that in larger cities. This study analyzed a medium-sized city, Jiaozuo, as an example, with the help of point of interest (POI) data, OpenStreetMap road network density data and WorldPop population data. The vitality of parks and squares in different functional spaces in the main urban area in Jiaozuo was quantitatively evaluated in terms of the four following aspects: urban space functional area characteristics, travel vitality index of urban residents, park and square attractiveness and the regional service levels of parks and squares. The effects of functional mixing, traffic network density, population density and spatial distribution on the vitality of parks and squares in medium-sized cities were also studied. The results showed that (1) the functional mixing in the main urban area in Jiaozuo was characterized by a spatial distribution of high in the center and low in the surrounding areas, with the highest functional mixing in the central part of the Jiefang District; (2) the travel dynamics of urban residents were characterized by a clear development of concentric circles radiating in a circular pattern; (3) the levels of service in parks and squares were particularly high in Jiefang District, with a spatial distribution of Jiefang District > Shanyang District > Macun District > Zhongzhan District; (4) under the condition that the service levels of each district were the same, the vitality values of the existing parks and squares in each district were compared and, from high to low, were Jiefang District (1.0-3.5), Shanyang District (0.2-2.0), Macun District (0-1.4) and Zhongzhan District (0-1.2). Functional mixing, road networks and population density had significant impacts on the vitality of parks and squares. Based on our study on the division of urban functional areas, we expanded the study to include urban microspaces. By evaluating the vitality of existing parks and squares and analyzing the influencing factors of spatial vitality, we found that it would be helpful to adopt targeted strategies to improve spatial vitality. Considering the spatial layouts of parks and squares, planning and constructing high-vitality parks and squares would be conducive to the future development of medium-sized cities. The existence of high-vitality spaces could also help to realize the sustainable development of cities.

A Novel Secreted Protein-Related Gene Signature Predicts Overall Survival and Is Associated With Tumor Immunity in Patients With Lung Adenocarcinoma.

Secreted proteins are important proteins in the human proteome, accounting for approximately one-tenth of the proteome. However, the prognostic value of secreted protein-related genes has not been comprehensively explored in lung adenocarcinoma (LUAD). In this study, we screened 379 differentially expressed secretory protein genes (DESPRGs) by analyzing the expression profile in patients with LUAD from The Cancer Genome Atlas database. Following univariate Cox regression and least absolute shrinkage and selection operator method regression analysis, 9 prognostic SPRGs were selected to develop secreted protein-related risk score (SPRrisk), including CLEC3B, C1QTNF6, TCN1, F2, FETUB, IGFBP1, ANGPTL4, IFNE, and CCL20. The prediction accuracy of the prognostic models was determined by Kaplan-Meier survival curve analysis and receiver operating characteristic curve analysis. Moreover, a nomogram with improved accuracy for predicting overall survival was established based on independent prognostic factors (SPRrisk and clinical stage). The DESPRGs were validated by quantitative real-time PCR and enzyme-linked immunosorbent assay by using our clinical samples and datasets. Our results demonstrated that SPRrisk can accurately predict the prognosis of patients with LUAD. Patients with a higher risk had lower immune, stromal, and ESTIMATE scores and higher tumor purity. A higher SPRrisk was also negatively associated with the abundance of CD8+ T cells and M1 macrophages. In addition, several genes of the human leukocyte antigen family and immune checkpoints were expressed in low levels in the high-SPRrisk group. Our results provided some insights into assessing individual prognosis and choosing personalized treatment modalities.

Graphene quantum dots-based targeted nanoprobes detecting drug delivery, imaging, and enhanced chemotherapy of nasopharyngeal carcinoma.

One of the main clinical treatments for advanced nasopharyngeal carcinoma is chemotherapy, but systemic administration can cause serious adverse reactions. New type of nanomaterial which can actively targeting, imaging, and treating nasopharyngeal carcinoma at the same time to enhance the effect of chemotherapy, meanwhile monitoring the intracellular drug release process at the level of single cancer cell was urgently needed. GE11, an EGFR antagonist peptide, was used to target nasopharyngeal carcinoma which has positive expression of EGFR on its nucleus. GE11-modified graphene quantum dots (GQDs@GE11) were used as drug carriers for clinical chemotherapeutics cisplatin (CDDP) and doxorubicin (DOX). The emission spectrum of GQDs (460 nm) and the excitation spectrum of DOX (470 nm) have a good overlap, thus the transfer and release process of DOX can be sensitively detected by the fluorescence resonance energy transfer (FRET). CDDP was used to enhance the chemotherapy effect of nanoprobe, and the loading amount of DOX and CDDP on GQDs@GE11 nanoprobe were up to 67 and 50 mg/g, respectively. In vivo experiments have confirmed that GQDs@GE11/CDDP/DOX nanoprobe can be enriched to tumor site through specific targeting effect, and significantly inhibit tumor cell proliferation. This new type of targeted therapy fluorescent probe provides new ideas for the study of drug release process and the treatment of nasopharyngeal carcinoma.

CircRAPGEF5 interacts with RBFOX2 to confer ferroptosis resistance by modulating alternative splicing of TFRC in endometrial cancer.

Endometrial cancer (EC) is one of the most common gynecological cancers. Ferroptosis is a newly identified form of cell death characterized by iron-dependent lipid peroxide accumulation. Circular RNAs (circRNAs) have emerged as critical regulators for cancer development. However, circRNA-mediated modulation of ferroptosis in EC is yet to be clarified. In this study, we found that circRAPGEF5 expression was elevated in EC tissues compared to the normal endometrial tissues. In vitro and in vivo functional analysis demonstrated that circRAPGEF5 facilitates rapid proliferation of EC cells. RNA binding protein fox-1 homolog 2 (RBFOX2), a splicing regulator, was identified as the protein interacts with circRAPGEF5. Further studies revealed that circRAPGEF5 can bind to the Fox-1 C-terminal domain of RBFOX2 and induces specific exon exclusion of TFRC through obstructing the binding of RBFOX2 to pre-mRNA. As a result, elevated levels of circRAPGEF5 lead to ferroptosis resistance via the decreased labile iron pool and attenuated lipid peroxide production in EC cells. Additionally, a series of gain- and loss-of-function experiments demonstrated that knocking down or overexpressing RBFOX2 reversed the effects of knocking down or overexpressing circRAPGEF5 in EC cells. Finally, it is revealed that circRAPGEF5 promote the formation of TFRC with exon-4 skipping and confer ferroptosis resistance in EC cells through the interaction with RBFOX2. Collectively, these findings provide new insight into the molecular mechanism in which circRNAs mediate mediates ferroptosis via modulating alternative splicing, and circRAPGEF5/RBFOX2 splicing axis could be a promising therapeutic target for treating EC.

Blockade of phosphotyrosine pathways suggesting SH2 superbinder as a novel therapy for pulmonary fibrosis.

Background: Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible fibrotic disease with high mortality. Currently, pirfenidone and nintedanib are the only approved drugs for IPF by the U.S. Food and Drug Administration (FDA), but their efficacy is limited. The activation of multiple phosphotyrosine (pY) mediated signaling pathways underlying the pathological mechanism of IPF has been explored. A Src homology-2 (SH2) superbinder, which contains mutations of three amino acids (AAs) of natural SH2 domain has been shown to be able to block phosphotyrosine (pY) pathway. Therefore, we aimed to introduce SH2 superbinder into the treatment of IPF. Methods: We analyzed the database of IPF patients and examined pY levels in lung tissues from IPF patients. In primary lung fibroblasts obtained from IPF patient as well as bleomycin (BLM) treated mice, the cell proliferation, migration and differentiation associated with pY were investigated and the anti-fibrotic effect of SH2 superbinder was also tested. In vivo, we further verified the safety and effectiveness of SH2 superbinder in multiple BLM mice models. We also compared the anti-fibrotic effect and side-effect of SH2 superbinder and nintedanib in vivo. Results: The data showed that the cytokines and growth factors pathways which directly correlated to pY levels were significantly enriched in IPF. High pY levels were found to induce abnormal proliferation, migration and differentiation of lung fibroblasts. SH2 superbinder blocked pY-mediated signaling pathways and suppress pulmonary fibrosis by targeting high pY levels in fibroblasts. SH2 superbinder had better therapeutic effect and less side-effect compare to nintedanib in vivo. Conclusions: SH2 superbinder had significant anti-fibrotic effects both in vitro and in vivo, which could be used as a promising therapy for IPF.

Splicing factor SRSF6 mediates pleural fibrosis.

Pleural fibrosis is defined as an excessive deposition of extracellular matrix that results in destruction of the normal pleural tissue architecture and compromised function. Tuberculous pleurisy, asbestos injury, and rheumatoid pleurisy are main causes of pleural fibrosis. Pleural mesothelial cells (PMCs) play a key role in pleural fibrosis. However, detailed mechanisms are poorly understood. Serine/arginine-rich protein SRSF6 belongs to a family of highly conserved RNA-binding splicing-factor proteins. Based on its known functions, SRSF6 should be expected to play a role in fibrotic diseases. However, the role of SRSF6 in pleural fibrosis remains unknown. In this study, SRSF6 protein was found to be increased in cells of tuberculous pleural effusions (TBPE) from patients, and decellularized TBPE, bleomycin, and TGF-ß1 were confirmed to increase SRSF6 levels in PMCs. In vitro, SRSF6 mediated PMC proliferation and synthesis of the main fibrotic protein COL1A2. In vivo, SRSF6 inhibition prevented mouse experimental pleural fibrosis. Finally, activated SMAD2/3, increased SOX4, and depressed miRNA-506-3p were associated with SRSF6 upregulation in PMCs. These observations support a model in which SRSF6 induces pleural fibrosis through a cluster pathway, including SRSF6/WNT5A and SRSF6/SMAD1/5/9 signaling. In conclusion, we propose inhibition of the splicing factor SRSF6 as a strategy for treatment of pleural fibrosis.

Crosstalk between pleural mesothelial cell and lung fibroblast contributes to pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a specific form of chronic, progressive and fibrosing interstitial pneumonia of unknown cause. The main feature of IPF is a heterogeneous appearance with areas of sub-pleural fibrosis. However, the mechanism of sub-pleural fibrosis was poorly understood. In this study, our in vivo study revealed that pleural mesothelial cells (PMCs) migrated into lung parenchyma and localized alongside lung fibroblasts in sub-pleural area in mouse pulmonary fibrosis. Our in vitro study displayed that cultured-PMCs-medium induced lung fibroblasts transforming into myofibroblast, cultured-fibroblasts-medium promoted mesothelial-mesenchymal transition of PMCs. Furthermore, these changes in lung fibroblasts and PMCs were prevented by blocking TGF-ß1/Smad2/3 signaling with SB431542. TGF-ß1 neutralized antibody attenuated bleomycin-induced pulmonary fibrosis. Similar to TGF-ß1/Smad2/3 signaling, wnt/ß-catenin signaling was also activated in the process of PMCs crosstalk with lung fibroblasts. Moreover, inhibition of CD147 attenuated cultured-PMCs-medium induced collagen-I synthesis in lung fibroblasts. Blocking CD147 signaling also prevented bleomycin-induced pulmonary fibrosis. Our data indicated that crosstalk between PMC and lung fibroblast contributed to sub-pleural pulmonary fibrosis. TGF-ß1, Wnt/ß-catenin and CD147 signaling was involved in the underling mechanism.

Separation of polyvinylchloride and acrylonitrile-butadiene-styrene combining advanced oxidation by S2O82-/Fe2+ system and flotation.

A combining technology of advanced oxidation by S2O82-/Fe2+ system and flotation was proposed for separating polyvinyl chloride (PVC) and acrylonitrile butadiene styrene (ABS). In this research, sodium persulfate was activated by heating and ferrous ions. The separation efficiency of PVC/ABS oxidized by S2O82-/Fe2+ was higher than that by sodium persulfate. The mechanism of this process was investigated through contact angle, Fourier transform infrared spectroscopy (FT-IR) inductively coupled plasma (ICP), nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS). The floatability of ABS reduced owing to the introduction of oxygen-containing functional groups such as carbonyl (OCO) and hydroxyl (OH), which was a result of oxidation by sulfate radicals (SO4·-). The optimal conditions for separating PVC and ABS were: Na2S2O8 concentration 0.1 M, molar ratio (S2O82-/Fe2+) 200, treatment time 10 min, flotation time 4 min, frother concentration 14.7 mg L-1 and airflow rate 6.8 mL min-1. Novel kinetics of pretreatment time and flotation were proposed and researched in this work. The max rate constant of PVC/ABS flotation was 0.64 min-1. In addition, the pretreatment solution can be reused for three times with superior performance. The recovery and purity of PVC reached 100% and 99.7%, respectively. According to reasonable evaluation, the combination of S2O82-/Fe2+ advanced oxidation and flotation is a practical and efficient technology for separating PVC and ABS.

Combination of sodium hypochlorite pretreatment and flotation towards separation of polycarbonate from waste plastic mixtures.

This study developed a novel method, surface pretreatment using sodium hypochlorite along with flotation, to facilitate separation of waste polycarbonate from plastic mixtures for recycling. Surface pretreatment was observed that has an obviously negative effect on the floating ratio of polycarbonate and the floating ratio of poly-methyl-methacrylate, polystyrene, and polyvinylchloride was not affected in flotation, and this difference in floating ratio can be expected to separate polycarbonate from plastic mixtures. The optimum conditions obtained included sodium hypochlorite concentration of 0.05 M, pretreatment temperature of 70.0 °C, pretreatment time of 60.0 min, frother dosage of 10.8 mg/L, and flotation time of 4.0 min. Under optimum conditions, polycarbonate was separated effectively from multiple plastic mixtures, and the purity and recovery were 99.8% and 100.0%, respectively. The major mechanism of surface pretreatment was ascertained by the aid of Fourier transform infrared, scanning electron microscope, energy dispersive spectrometer, and X-ray photoelectron spectroscopy, and the hydrophilic groups, pitting, and protuberances introduced on polycarbonate surface caused the reduced floating ratio of polycarbonate. Accordingly, this method can be expected to improve the recycling quality of waste plastics, and provides technological insights in the environmentally friendly disposal of waste plastics.