ABSTRACT
Due to boron's metalloid properties, aromatic boron reagents are prevalent synthetic intermediates. The direct borylation of aryl C-H bonds for producing aromatic boron compounds offers an appealing, one-step solution. Despite significant advances in this field, achieving regioselective aryl C-H bond borylation using simple and readily available starting materials still remains a challenge. In this work, we attempted to enhance the reactivity of the electron-donor-acceptor (EDA) complex by selecting different bases to replace the organic base (NEt3) used in our previous research. To our delight, when using NH4HCO3 as the base, we have achieved a mild visible-light-mediated aromatic C-H bond borylation reaction with exceptional regioselectivity (rr > 40:1 to single isomers). Compared with our previous borylation methodologies, this protocol provides a more efficient and broader scope for aryl C-H bond borylation through the use of N-Bromosuccinimide. The protocol's good functional-group tolerance and excellent regioselectivity enable the functionalization of a variety of biologically relevant compounds and novel cascade transformations. Mechanistic experiments and theoretical calculations conducted in this study have indicated that, for certain arenes, the aryl C-H bond borylation might proceed through a new reaction mechanism, which involves the formation of a novel transient EDA complex.
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As a plant-specific endoreplication regulator, the SIAMESE-RELATED (SMR) family (a cyclin-dependent kinase inhibitor) plays an important role in plant growth and development and resistance to stress. Although the genes of the maize (Zea mays) SMR family have been studied extensively, the ZmSMR10 (Zm00001eb231280) gene has not been reported. In this study, the function of this gene was characterized by overexpression and silencing. Compared with the control, the transgenic plants exhibited the phenotypes of early maturation, dwarfing, and drought resistance. Expression of the protein in prokaryotes demonstrates that ZmSMR10 is a small protein, and the results of subcellular localization suggest that it travels functionally in the nucleus. Unlike ZmSMR4, yeast two-hybrid experiments demonstrated that ZmSMR10 does not interact strongly with with some cell cycle protein-dependent protein kinase (CDK) family members ZmCDKA;1/ZmCDKA;3/ZmCDKB1;1. Instead, it interacts strongly with ZmPCNA2 and ZmCSN5B. Based on these results, we concluded that ZmSMR10 is involved in the regulation of endoreplication through the interaction of ZmPCNA2 and ZmCSN5B. These findings provide a theoretical basis to understand the mechanism of the regulation of endoreplication and improve the yield of maize through the use of molecular techniques.
Subject(s)
Arabidopsis , Endoreduplication , Arabidopsis/genetics , Cell Cycle Proteins/metabolism , Cyclin-Dependent Kinase Inhibitor Proteins/metabolism , Plants, Genetically Modified/metabolism , Gene Expression Regulation, Plant , Zea mays/genetics , Zea mays/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Stress, Physiological/genetics , DroughtsABSTRACT
Cancer is a significant global health concern, and finding effective methods to treat it has been a focus of scientific research. It has been discovered that the growth, invasion, and metastasis of tumors are closely related to the environment in which they exist, known as the tumor microenvironment (TME). The immune response interacting with the tumor occurring within the TME constitutes the tumor immune microenvironment, and the immune response can lead to anti-tumor and pro-tumor outcomes and has shown tremendous potential in immunotherapy. A channel called the P2X7 receptor (P2X7R) has been identified within the TME. It is an ion channel present in various immune cells and tumor cells, and its activation can lead to inflammation, immune responses, angiogenesis, immunogenic cell death, and promotion of tumor development. This article provides an overview of the structure, function, and pharmacological characteristics of P2X7R. We described the concept and components of tumor immune microenvironment and the influence immune components has on tumors. We also outlined the impact of P2X7R regulation and how it affects the development of tumors and summarized the effects of drugs targeting P2X7R on tumor progression, both past and current, assisting researchers in treating tumors using P2X7R as a target.
Subject(s)
Neoplasms , Receptors, Purinergic P2X7 , Tumor Microenvironment , Humans , Neoplasms/metabolism , Receptors, Purinergic P2X7/metabolism , AnimalsABSTRACT
Purpose: Eosinophils have pivotal roles in the development of allergic rhinitis (AR) through the release of cytotoxic substances. Apolipoprotein A-I (Apo-AI) exhibits a strong inhibitory effect on eosinophil infiltration in allergic diseases. Nevertheless, the precise impact of Apolipoprotein A-I on eosinophils remains uncertain. Methods: Our study recruited a total of 15 AR children and 15 controls. The correlation between Apo-AI expression and the counts of blood eosinophils was examined. Flow cytometry was employed to assess the role of Apo-AI in eosinophil apoptosis and adhesion. The Transwell system was performed to conduct the migration assay. An animal model using AR mice was established to test the effect of Apo-AI on eosinophils. Results: Serum Apo-AI were negatively related to eosinophils counts and eosinophil chemotactic protein levels in AR. Apo-AI exerts a pro-apoptotic effect while also impeding the processes of adhesion, migration, and activation of eosinophils. The apoptosis triggered by Apo-AI was facilitated through the phosphoinositide 3-kinase (PI3K) pathway. The chemotaxis and activation of eosinophils, which are influenced by Apolipoprotein A-I, are regulated through the PI3K and MAPK signaling pathways. Apo-AI treated mice presented with decreased blood and nasal eosinophilic inflammation as well as down-regulated eosinophil related cytokines. Conclusion: Our findings provide confirmation that Apo-AI exhibits inhibitory effects on the function of eosinophils in allergic rhinitis. This suggests that Apo-AI holds potential as a therapeutic target for future treatment strategies.
ABSTRACT
Background: Group 2 innate lymphoid cells (ILC2s) have been found to take part in type 2 inflammation by secreting TH2 cytokines. Apolipoprotein A-I (Apo-AI), a major structural and functional protein of high-density lipoproteins, has anti-inflammatory effects on neutrophils, monocytes, macrophages, and eosinophils. However, its effects on ILC2s are not well characterized. Objective: We aimed to investigate the effect of Apo-AI on the proliferation and function of ILC2s as well as its possible mechanism. Methods: The protein expression of Apo-AI and the percentage of ILC2s in peripheral blood between 20 allergic rhinitis patients and 20 controls were detected by ELISA and flow cytometry. The effect of Apo-AI and miR-155 on ILC2 proliferation and function was detected by tritiated thymidine incorporation and ELISA. Anima models were adopted to verify the effect of Apo-AI in vivo. Results: Elevated expression of Apo-AI was observed in allergic rhinitis patients. Apo-AI promotes ABCA1 expression by ILC2s, which can be inhibited by anti-Apo-AI. Apo-AI decreased ILC2 proliferation and the microRNA levels of GATA3 and RORα from ILC2s. The miR-155 overexpression promoted the upregulation of GATA3 and type II cytokines from ILC2s, while the addition of Apo-AI or miR-155 inhibitor significantly inhibited expression of GATA3 and type II cytokines by ILC2s. Apo-AI-/- mice showed as enhanced allergen-induced airway inflammation. The miR-155 inhibitor can reverse the enhanced allergen-induced airway inflammation in Apo-AI-/- mice, while miR-155 mimics can reverse the decreased allergen-induced airway inflammation in Apo-AI-treated mice. Conclusion: Apo-AI suppressed the proliferation and function of ILC2s through miR-155 in allergic rhinitis. Our data provide new insights into the mechanism of allergen-induced airway inflammation.
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Despite growing prevalence and incidence, the management of gout remains suboptimal. The intermittent nature of the gout makes the long-term urate-lowering therapy (ULT) particularly important for gout management. However, patients are reluctant to take medication day after day to manage incurable occasional gout flares, and suffer from possible long-term toxicity. Therefore, a safe and easy-to-operate drug delivery system with simple preparation for the long-term management of gout is very necessary. Here, a chitosan-containing sustained-release microneedle system co-loaded with colchicine and uricase liposomes were fabricated to achieve this goal. This microneedle system was confirmed to successfully deliver the drug to the skin and maintain a one-week drug retention. Furthermore, its powerful therapeutic potency to manage gout was investigated in both acute gouty and chronic gouty models. Besides, the drug co-delivery system could help avoid long-term daily oral colchicine, a drug with a narrow therapeutic index. This system also avoids mass injection of uricase by improving its stability, enhancing the clinical application value of uricase. In general, this two-drug system reduces the dosage of uricase and colchicine and improves the patient's compliance, which has a strong clinical translation.
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Piezo channels are critical cellular sensors of mechanical forces. Despite their large size, ubiquitous expression, and irreplaceable roles in an ever-growing list of physiological processes, few Piezo channel-binding proteins have emerged. In this work, we found that MyoD (myoblast determination)-family inhibitor proteins (MDFIC and MDFI) are PIEZO1/2 interacting partners. These transcriptional regulators bind to PIEZO1/2 channels, regulating channel inactivation. Using single-particle cryogenic electron microscopy, we mapped the interaction site in MDFIC to a lipidated, C-terminal helix that inserts laterally into the PIEZO1 pore module. These Piezo-interacting proteins fit all the criteria for auxiliary subunits, contribute to explaining the vastly different gating kinetics of endogenous Piezo channels observed in many cell types, and elucidate mechanisms potentially involved in human lymphatic vascular disease.
Subject(s)
Ion Channels , Myogenic Regulatory Factors , Humans , Cryoelectron Microscopy , HEK293 Cells , Ion Channel Gating , Ion Channels/chemistry , Ion Channels/genetics , Ion Channels/metabolism , Kinetics , Lymphatic Diseases/genetics , Mutation , Myogenic Regulatory Factors/chemistry , Myogenic Regulatory Factors/genetics , Myogenic Regulatory Factors/metabolism , Protein Domains , Myoblasts/metabolism , Animals , MiceABSTRACT
Background: Allergen-specific immunotherapy, including subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT), improves the disease progression of allergic rhinitis (AR). SCIT and SLIT exhibit similar efficacy, but SLIT has less systemic reactions. However, few studies have investigated the underlying mechanisms of SLIT treatment. In this study, we explored the efficacy of SLIT under different treatment durations and immunological changes. Methods: This retrospective study was conducted from August 2017 to August 2022 in our hospital. A total of 314 children who underwent SLIT were divided into the following groups based on their treatment duration: the 1 year group (6 months-1 year), the 2 years group (1-2 years), and the 3 years group (2-3 years). The treatment efficacy was confirmed using a combined symptom and medication score (SMS). Multiple serum cytokines were measured using Luminex. Various immune cells in PBMCs were determined using flow cytometry. Results: The total nasal symptom score (TNSS), rescue medication score (RMS), and SMS of the 3 years group was significantly different from those of the 1 years and 2 years groups. At the end of the 2 years following cessation of SLIT, the following results were observed in the 3 years group: 1) the TNSS, RMS, and SMS had significantly improved, 2) the serum IL-10, TGF-beta, and IL-35 levels had increased significantly, and 3) the percentages of regulatory T cell, regulatory B cell, and follicular regulatory T cell increased significantly. Conclusion: Our results suggest that 3 years of SLIT is necessary for long-term effects and continued immunological changes.
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AIM: To explore whether 14, 15-EET regulates mitochondrial dynamics to exert neuroprotective effects after cerebral ischemia-reperfusion and its underlying mechanisms. METHODS: The mouse middle cerebral artery occlusion reperfusion model was used to observe brain infarct volume and neuronal apoptosis by TTC staining and Tunel assay, modified neurological severity score to detect neurological impairment, HE staining and Nissl staining to observe neuron damage, western blot and immunofluorescence methods to detect the expression of mitochondrial dynamics-related proteins, transmission electron microscopy, and Golgi-Cox staining to detect mitochondrial morphology and neuronal dendritic spines. RESULTS: 14, 15-EET reduced the neuronal apoptosis and cerebral infarction volume induced by middle cerebral artery occlusion reperfusion (MCAO/R), inhibited the degradation of dendritic spines, maintained the structural integrity of neurons, and alleviated neurological impairment. Cerebral ischemia-reperfusion induces mitochondrial dynamics disorders, upregulates the expression of the mitochondrial division protein Fis 1, and inhibits the expression of mitochondrial fusion proteins MFN1, MFN2, and OPA1, while 14, 15-EET treatment reverses this process. Mechanistic studies have shown that 14, 15-EET promotes the phosphorylation of AMPK, upregulates the expression of SIRT1 and phosphorylation of FoxO1, thereby inhibiting mitochondrial division and promoting mitochondrial fusion, preserving mitochondrial dynamics, maintaining neuronal morphological and structural integrity, and alleviating neurological impairment induced by middle cerebral artery occlusion reperfusion. Compound C treatment diminishes the neuroprotective effect of 14, 15-EET following MCAO/R in mice. CONCLUSION: This study elucidates the novel neuroprotective mechanism of 14, 15-EET, providing a novel approach for the development of drugs based on mitochondrial dynamics.
Subject(s)
Brain Ischemia , Neuroprotective Agents , Reperfusion Injury , Mice , Animals , Mitochondrial Dynamics , AMP-Activated Protein Kinases/metabolism , Infarction, Middle Cerebral Artery/drug therapy , Infarction, Middle Cerebral Artery/metabolism , Sirtuin 1/metabolism , Reperfusion Injury/drug therapy , Reperfusion Injury/metabolism , Brain Ischemia/drug therapy , Brain Ischemia/metabolism , Apoptosis , Signal Transduction , Reperfusion , Neuroprotective Agents/pharmacologyABSTRACT
Background: Interleukin-37b is a fundamental inhibitor of innate and acquired immunity. Type 2 innate lymphoid cells (ILC2s) can secret type 2 cytokines and regulate allergic rhinitis (AR). However, the role of IL-37b in ILC2s in children with AR was not clear. Methods: We recruited 15 AR children and controls. The serum IL-37b levels and its relation with the frequency and functional phenotype of ILC2s. The regulation of IL-37b on ILC2s proliferation and function was confirmed using flow cytometry and enzyme-linked immunosorbent assay (ELISA). The mRNA expression of IL-1R8, IL-18Rα, and ICOSL was examined using RCR. The change of IL-37b protein level in serum during subcutaneous allergen immunotherapy (SCIT) was determined by ELISA. Results: We have demonstrated that both of the frequencies of blood ILC2s, IL-5+ILC2s, and IL-13+ILC2s in AR children were elevated compared with controls. The serum protein level of IL-37b was downregulated in AR, and it was negatively related to the frequency of ILC2s, IL-5+ILC2s, and IL-13+ILC2s. IL-37b increased the mRNA levels of IL-1R8, IL-18Rα, and ICOSL expressed by ILC2s. IL-37b suppressed the proliferation of ILC2s and the secretion of IL-5 and IL-13 from ILC2s. Finally, we found that IL-37b was increased in AR children after 3 years' SLIT, especially in the good response group. Conclusion: Our findings highlight the role of IL-37b in the suppression of ILC2s and establish a new therapeutic target in AR.
Subject(s)
Immunity, Innate , Rhinitis, Allergic , Humans , Interleukin-13/metabolism , Interleukin-5/metabolism , Lymphocytes/metabolism , Interleukins/metabolism , Cytokines/metabolismABSTRACT
Bivariate flow cytometry (FC) sorting with forward scatter (FSC) and side scatter (SSC) is a recently established novel technique to separate starch granules. However, the forming mechanism of starch FC-dependent population patterns (i.e. the number of subgroups (NS) and FSC/SSC-dependent distribution patterns) remain partly elusive. For this, the correlation of granular size and multi-scale structure of native starches and FC-dependent population patterns was investigated through employing a wide range of native starches originating from different species involving cereal-, pulse-, and tuber crops. Results showed NS was pertinent with particle size, amylose content (AC), amylopectin chains length distribution, lamellar structure, short-range ordered structure. The distinct NS was determined by impacts of native starch FSC / SSC-dependent distribution patterns. Specifically, starch granular size significantly correlated with both FSC and SSC-dependent distribution patterns. The proportion of chains with DP 6-12 was the intra-molecular decisive factor to influence short-range ordered structure, finally leading to FSC-dependent distribution patterns. By contrast, AC was another intra-molecular index to determine SSC-dependent distribution patterns through affecting lamellar structure and short-range ordered structure.
Subject(s)
Amylopectin , Starch , Starch/chemistry , Flow Cytometry , Amylopectin/chemistry , Amylose/chemistry , Particle SizeABSTRACT
BACKGROUND AND OBJECTIVE: The major contributing risk factors to airflow obstruction (AO) in China remain largely unknown. We examined the environmental and lifestyle risk factors of unrecognized AO in the baseline of a population-based cohort drawn from 115 urban and rural communities across 12 provinces in China. METHODS: Amongst 46,285 adults recruited from 2005 to 2009, 3686 were identified with AO on spirometry (defined by the ratio of forced expiratory volume in the first second to forced vital capacity <0.7) and without known chronic lung disease. These cases were age- and sex-matched to 11,129 controls with normal spirometry and no chronic lung disease from the same community. Conditional multivariable adjusted OR and population attributable fraction (PAF) were calculated for each identified risk factor and their combined effect. RESULTS: Compared to controls, smoking initiation age <20 years (OR 1.22 [95% CI 1.01-1.48]), smoking duration ≥40 years (OR 1.82 [1.50-2.22]), low vegetables (OR 1.86 [1.67-2.07]) and fruits (OR 1.14 [1.02-1.29]) intake, cooking with biomass fuels (OR 2.54 [2.32-2.78]) and poor kitchen ventilation (OR 1.37 [1.19-1.58]) were significantly associated with elevated risks of unrecognized AO. The combined effect of these lifestyle factors significantly elevated the odds by 25 fold (18.6-34.3). The addition of prior tuberculosis and low socioeconomic status further increased the odds to 40.1 (28.2-57.0) and the PAF to 66.7% (51.1-78.1). CONCLUSION: Smoking, unhealthy diet, biomass cooking fuels and low socioeconomic status are strongly associated with AO. Addressing these risk factors could substantially reduce the burden of AO in China.
Subject(s)
Pulmonary Disease, Chronic Obstructive , Adult , Humans , Young Adult , Pulmonary Disease, Chronic Obstructive/epidemiology , Pulmonary Disease, Chronic Obstructive/etiology , Case-Control Studies , Prevalence , Forced Expiratory Volume , Vital Capacity , Spirometry , Cooking , Smoking/adverse effects , Smoking/epidemiology , China/epidemiology , Risk Factors , Diet/adverse effectsABSTRACT
Mechanosensing is an integral part of many physiological processes including stem cell differentiation, fibrosis, and cancer progression. Two major mechanosensing systems-focal adhesions and mechanosensitive ion channels-can convert mechanical features of the microenvironment into biochemical signals. We report here unexpectedly that the mechanosensitive calcium-permeable channel Piezo1, previously perceived to be diffusive on plasma membranes, binds to matrix adhesions in a force-dependent manner, promoting cell spreading, adhesion dynamics, and calcium entry in normal but not in most cancer cells tested except some glioblastoma lines. A linker domain in Piezo1 is needed for binding to adhesions, and overexpression of the domain blocks Piezo1 binding to adhesions, decreasing adhesion size and cell spread area. Thus, we suggest that Piezo1 is a previously unidentified component of focal adhesions in nontransformed cells that catalyzes adhesion maturation and growth through force-dependent calcium signaling, but this function is absent in most cancer cells.
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The chemical stability of the anion exchange membranes (AEMs) is determinative towards the engineering applications of anion exchange membrane fuel cells (AEMFCs) and other AEM-based electrochemical devices, yet remains a challenge due to deficiencies in the structural design of cations. In this work, an effective design strategy for ultra-stable piperidinium cations is presented based on the systematic investigation of the chemical stability of piperidinium in harsh alkaline media. Firstly, benzyl-substituted piperidinium was degraded by about 23% in a 7 M KOH solution at 100 °C after 1436 h, which was much more stable than pyrrolidinium due to its lower ring strain. The introduction of substituent effects at the α-C position was proved to be an effective strategy for enhancing the chemical stability of the piperidinium functional group. As a result, the butyl-substituted piperidinium cation showed no obvious structural changes after being treated in the 7 M KOH solution at 100 °C for 1050 h. Afterwards, GC-MS and NMR analysis indicated that the α-C atoms in the substituents of piperidinium are fragile to the nucleophilic attack of OH-. Based on the above results, the electronic and steric effects of different alkyl substitutions were analyzed. This work provides critical insights into the structural design of chemically stable piperidinium functional groups for the AEM and boosts its application in electrochemical devices, such as fuel cells and alkaline water electrolysis.
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Since the colorimetric method has the characteristics of being simple and low cost, the fluorescence spectrum has the characteristics of a strong signal, and Surface-enhanced Raman scattering (SERS) detection has the characteristics of high sensitivity and strong specificity, people usually use these three methods for detection, but the detection of a single sample takes more time. If multiple samples can be tested at the same time, the detection efficiency and sensitivity can be improved, and the selectivity and reliability will be greatly improved. Multiplex sensing also provides a new direction for researchers. To fully understand the research of multiplex sensing based on the plasmonic optics of noble metal nanostructures, this review summarizes all the results previously reported in this field. It also discusses the principles of various detection methods and the biochemical application of multiple detections and finally summarizes the challenges and prospects.
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Acute myeloid leukemia (AML) is a highly heterogeneous hematological malignancy that imposes great challenges in terms of drug resistance and relapse. Previous studies revealed heterogeneous leukemia cells and their relevant gene markers, such as CRIP1 as clinically prognostic in t (8;21) AML patients. However, the expression and role of CRIP1 in AML are poorly understood. We used the single-cell RNA sequencing and gene expression data from t (8;21) AML patients to analyze the immune and regulation networks of CRIP1. Two independent cohorts from GSE37642 and The Cancer Genome Atlas (TCGA) datasets were employed as validation cohorts. In addition, the methylation data from TCGA were used to analyze the methylation effect of the CRIP1 expression. Gene expression profile from t (8;21) AML patients showed that the CRIP1-high group exhibited an enrichment of immune-related pathways, including tumor necrosis factor (TNF)α signaling via nuclear factor kappa B (NFκB) pathways. Further studies using CIBERSORT showed that the CRIP1-high group had a significantly higher infiltration of exhausted CD8 T cells and activated mast cells. The CRIP1 expression was validated in the GSE37642-GPL96, GSE37642-GPL570, and TCGA datasets. In addition, with the methylation data, four CpG probes of CRIP1 (cg07065217, cg04411625, cg25682097, and 11763800) were identified as negatively associated with the CRIP1 gene expression in AML patients. Our data provide a comprehensive overview of the regulation of CRIP1 expression in AML patients. The evaluation of the TNFα-NFκB signaling pathway as well as the immune heterogeneity might provide new insights for exploring improvements in AML treatment.
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Objectives: Intestinal epithelial barrier function is an important mechanical barrier to maintain intestinal homeostasis and resist the invasion of intestinal pathogens and microorganisms. However, intestinal epithelial barrier function is vulnerable to damage under intestinal ischemia-reperfusion (I/R) injury. Under a category of pathophysiological conditions, including I/R, autophagy plays a crucial role. This study is aimed at discussing the role of autophagy inhibitors and activators in intestinal epithelial barrier function after intestinal I/R by changing autophagy levels. Methods: Mice with intestinal IR underwent 45 minutes of surgery for superior mesenteric artery occlusion. The autophagy inhibitor 3-MA and the autophagy inducer rapamycin (RAP) were used to change the level of autophagy, and then, the expressions of tight junction proteins and intestinal barrier function were detected. Results: The results showed that the autophagy inhibitor 3-MA aggravated intestinal epithelial barrier dysfunction, while the autophagy inducer RAP attenuated intestinal epithelial barrier dysfunction. In addition, promoting autophagy may promote occludin expression by inhibiting claudin-2 expression. Conclusion: Upregulation of autophagy levels by autophagy inducers can enhance intestinal epithelial barrier function after intestinal I/R.
Subject(s)
Autophagy , Reperfusion Injury , Animals , Intestinal Mucosa/metabolism , Ischemia , Mice , Reperfusion , Reperfusion Injury/metabolism , Tight Junction Proteins/metabolismABSTRACT
Coronavirus disease 2019 (COVID-19), which is known to be caused by the virus severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is characterized by pneumonia, cytokine storms, and lymphopenia. Patients with malignant tumors may be particularly vulnerable to SARS-CoV-2 infection and possibly more susceptible to severe complications due to immunosuppression. Recent studies have found that CD209 (DC-SIGN) might be a potential binding receptor for SARS-CoV-2 in addition to the well-known receptor ACE2. However, pan-cancer studies of CD209 remain unclear. In this study, we first comprehensively investigated the expression profiles of CD209 in malignancies in both pan-carcinomas and healthy tissues based on bioinformatic techniques. The CD209 expression declined dramatically in various cancer types infected by SARS-CoV-2. Remarkably, CD209 was linked with diverse immune checkpoint genes and infiltrating immune cells. These findings indicate that the elevation of CD209 among specific cancer patients may delineate a mechanism accounting for a higher vulnerability to infection by SARS-CoV-2, as well as giving rise to cytokine storms. Taken together, CD209 plays critical roles in both immunology and metabolism in various cancer types. Pharmacological inhibition of CD209 antigen (D-mannose), together with other anti-SARS-CoV-2 strategies, might provide beneficial therapeutic effects in specific cancer patients.
ABSTRACT
5Fluorouracil (5FU) is the preferred chemotherapeutic drug used in the treatment of colon cancer; however, drug resistance affects its clinical efficacy. Visfatin, an adipokine that promotes tumour development, has the potential to increase resistance to chemotherapy. The present study aimed to verify the effects of visfatin on the sensitivity of colon cancer cells to 5FU and to elucidate the potential mechanisms involved. Tissue microarrays (TMAs) were used to analyse visfatin differential expression in normal colon and colon cancer tissues, and the data were further validated in vitro. Cell Counting Kit8, clone formation, caspase3/7 activity assays, as well as other analyses were used to verify the effects of visfatin on sensitivity to 5FU. TMA and correlation analyses were used to predict and verify the correlation between visfatin and stromal cellderived factor1 (SDF1). Rescue experiments and PI3K/Akt inhibitors were used to verify the role of the visfatin/SDF1/Akt axis in the sensitivity of colon cancer cells to 5FU. Visfatin was found to be highly expressed in colon cancer tissues and cell lines. Moreover, visfatin knockdown increased apoptosis, reduced cell proliferation and enhanced the chemosensitivity of DLD1 and SW48 cells to 5FU. A positive correlation between visfatin and SDF1 was observed, with the knockdown of visfatin enhancing cell sensitivity to 5FU chemotherapy by targeting the SDF1/CXC chemokine receptor type 4 (CXCR4) axis. Furthermore, the Akt signalling pathway downstream of SDF1/CXCR4 proved to be critical in the decreased sensitisation of colon cancer cells to 5FU induced by visfatin. On the whole, the present study demonstrates that visatin can potentially decrease colon cancer cell apoptosis, promote proliferation and decrease colon cancer cell sensitivity to 5FU via the visfatin/SDF1/Akt axis.