Integrin-mediated Signaling Pathway Research Articles

Characterization of IL-6R-expressing monocytes in the lung of patients with chronic obstructive pulmonary disease

BackgroundMonocytes play a crucial role in innate immune responses for host defense, however, their involvement in chronic obstructive pulmonary disease (COPD) remains poorly understood. We previously identified a subset of monocytes in COPD lung tissues characterized by high interleukin-6 receptor (IL-6R) expression. This study aimed to characterize the phenotypes of IL-6Rhi monocytes in the lungs of COPD patients. MethodsUsing flow cytometry, we assessed the abundance of pulmonary CD14+IL-6Rhi cells in never smokers (CNS), control ex-smokers (CES) and COPD patients. IL-6 expression in CD14+ monocytes isolated from the peripheral blood of patients with COPD was also examined. CD45+CD206–CD14+IL-6Rhi and CD45+CD206–CD14+IL-6R–/lo cells were isolated from COPD lung tissues for transcriptome analysis. A monocyte line THP1 cell with constitutive IL-6R expression was stimulated with recombinant IL-6, followed by RNA sequencing to evaluate the IL-6 responsiveness of IL-6R+ monocytes. ResultsThe number of pulmonary CD14+IL-6Rhi monocytes was elevated in COPD patients compared to CNS, whereas CD14+ monocytes in the peripheral blood of COPD patients did not express IL-6R. Upregulated mRNA expression in CD14+IL-6Rhi monocytes was associated with chemotaxis, monocyte differentiation, fatty acid metabolism and integrin-mediated signaling pathway. Stimulation of THP1 cells with recombinant IL-6 induced changes in the expression of genes linked to chemotaxis and organism development. ConclusionIn patients with COPD, CD14+IL-6Rhi monocytes are increased in lung tissues compared to those in CNS. They exhibit a transcriptome profile different from that of CD14+IL-6R–/lo monocytes.

Gene expression profile of human placental villous pericytes in the first trimester – An analysis by single-cell RNA sequencing

Mesenchymal cells within theplacental villi play a crucial role in shaping the morphology of branching structures and driving the development of blood vessels. However, the markers and functions of placental villous pericytes (PVPs) as distinct subgroups of placental villous mesenchymal cells, remain unclear. Therefore, in this study, the markers and functions of PVPs were investigated. Single-cell sequencing data from the first-trimester placental villi was obtained and the Seurat tool was used to identify PVP markers. Gene Ontology (GO) analysis of specific genes was performed using the DAVID database. The Cellchat tool was employed to investigate the interaction signals between the PVPs and other cells. Expression of the PVP markers was confirmed using immunofluorescence. Presence of extracellular vesicles in the placental villous mesenchyme and PVPs was examined by transmission electron microscopy. Our findings revealed that renin (REN) and amphiregulin (AREG)-positive fibroblasts in the placental villi specifically expressed several classic pericyte markers. In the first trimester, certain conserved functions of pericytes were observed and they displayed tissue-specific functions such as in the integrin-mediated signaling pathway and extracellular exosomes. Moreover, the placental villous mesenchyme was found to be rich in extracellular vesicles. AREG is specifically transcribed in the first trimester PVPs, however, its protein was located in syncytiotrophoblasts. These insights contribute to a comprehensive understanding of early placental development and offer new therapeutic targets for placenta-derived pregnancy complications.

Integrative analysis of COL6A3 in lupus nephritis: insights from single-cell transcriptomics and proteomics.

Lupus nephritis (LN), a severe complication of systemic lupus erythematosus (SLE), presents significant challenges in patient management and treatment outcomes. The identification of novel LN-related biomarkers and therapeutic targets is critical to enhancing treatment outcomes and prognosis for patients. In this study, we analyzed single-cell expression data from LN (n=21) and healthy controls (n=3). A total of 143 differentially expressed genes were identified between the LN and control groups. Then, proteomics analysis of LN patients (n=9) and control (SLE patients without LN, n=11) revealed 55 differentially expressed genes among patients with LN and control group. We further utilizes protein-protein interaction network and functional enrichment analyses to elucidate the pivotal role of COL6A3 in key signaling pathways. Its diagnostic value is evaluate through its correlation with disease progression and renal function metrics, as well as Receiver Operating Characteristic Curve (ROC) analysis. Additionally, immunohistochemistry and qPCR experiments were performed to validate the expression of COL6A3 in LN. By comparison of single-cell and proteomics data, we discovered that COL6A3 is significantly upregulated, highlighting it as a critical biomarker of LN. Our findings emphasize the substantial involvement of COL6A3 in the pathogenesis of LN, particularly noting its expression in mesangial cells. Through comprehensive protein-protein interaction network and functional enrichment analyses, we uncovered the pivotal role of COL6A3 in key signaling pathways including integrin-mediated signaling pathways, collagen-activated signaling pathways, and ECM-receptor interaction, suggesting potential therapeutic targets. The diagnostic utility is confirmed by its correlation with disease progression and renal function metrics of the glomerular filtration rate. ROC analysis further validates the diagnostic value of COL6A3, with the area under the ROC values of 0.879 in the in-house cohort, and 0.802 and 0.915 in tubular and glomerular external cohort samples, respectively. Furthermore, immunohistochemistry and qPCR experiments were consistent with those obtained from the single-cell RNA sequencing and proteomics studies. These results proved that COL6A3 is a promising biomarker and therapeutic target, advancing personalized medicine strategies for LN.

Whole Exome Sequencing in Vaccine-Induced Thrombotic Thrombocytopenia (VITT).

Background: In February 2021, a few cases of unusual, severe thrombotic events associated with thrombocytopenia reported after vaccination with ChAdOx1 nCoV-19 (Vaxzevria) or with Johnson & Johnson's Janssen vaccine raise concern about safety. The vaccine-induced thrombotic thrombocytopenia (VITT) has been related to the presence of platelet-activating antibodies directed against platelet Factor 4. Objectives: We investigated VITT subject genetic background by a high-throughput whole exome sequencing (WES) approach in order to investigate VITT genetic predisposition. Methods: Six consecutive patients (females of Caucasian origin with a mean age of 64 years) were referred to the Atherothrombotic Diseases Center (Department of Experimental and Clinical Medicine, Azienda Ospedaliero-Universitaria Careggi, Florence) with a diagnosis of definite VITT underwent WES analysis. WES analysis was performed on the Illumina NextSeq500 platform. Results:WES analysis revealed a total of 140,563 genetic variants. Due to VITT's rare occurrence, we focused attention on rare variants. The global analysis of all high-quality rare variants did not reveal a significant enrichment of mutated genes in biological/functional pathways common to patients analyzed. Afterwards, we focused on rare variants in genes associated with blood coagulation and fibrinolysis, platelet activation and aggregation, integrin-mediated signaling pathway, and inflammation with particular attention to those involved in vascular damage, as well as autoimmune thrombocytopenia. According to ACMG criteria, 47/194 (24.2%) rare variants were classified as uncertain significance variants (VUS), whereas the remaining were likely benign/benign. Conclusion: WES analysis identifies rare variants possibly favoring the prothrombotic state triggered by the exposure to the vaccine. Functional studies and/or extensions to a larger number of patients might allow a more comprehensive definition of these molecular pathways.

Mining host candidate regulators of schistosomiasis-induced liver fibrosis in response to artesunate therapy through transcriptomics approach.

Artesunate (ART) has been reported to have an antifibrotic effect in various organs. The underlying mechanism has not been systematically elucidated. We aimed to clarify the effect of ART on liver fibrosis induced by Schistosoma japonicum (S. japonicum) in an experimentally infected rodent model and the potential underlying mechanisms. The effect of ART on hepatic stellate cells (HSCs) was assessed using CCK-8 and Annexin V-FITC/PI staining assays. The experimental model of liver fibrosis was established in the Mongolian gerbil model infected with S. japonicum cercariae and then treated with 20 mg/kg or 40 mg/kg ART. The hydroxyproline (Hyp) content, malondialdehyde (MDA) content, superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities in liver tissue were measured and histopathological changes of liver tissues were observed. Whole-transcriptome RNA sequencing (RNA-seq) of the liver tissues was performed. Differentially expressed genes (DEGs) were identified using bioinformatic analysis and verified by quantitative PCR (qPCR) and western blot assay. ART significantly inhibited the proliferation and induce the apoptosis of HSCs in a dose-dependent manner. In vivo, Hyp content decreased significantly in the ART-H group compared to the model (MOD) group and GPX activity was significantly higher in the ART-H group than in the MOD group. Besides, ART treatment significantly reduced collagen production (p <0.05). A total of 158 DEGs and 44 differentially expressed miRNAs related to ART-induced anti-schistosomiasis liver fibrosis were identified. The qPCR and western blot results of selected DEGs were consistent with the sequencing results. These DEGs were implicated in key pathways such as immune and inflammatory response, integrin-mediated signaling and toll-like receptor signaling pathways. ART is effective against liver fibrosis using Mongolian gerbil model induced by S. japonicum infection. We identified host candidate regulators of schistosomiasis-induced liver fibrosis in response to ART through transcriptomics approach.

Electroconductive and mechano-competent PUCL@CNT nanohybrid scaffolds guiding neuronal specification of neural stem/progenitor cells

Diseased or injured nervous systems lead to lifelong disability and even death due to their limited self-repair and regenerative capability. For successful neuronal regeneration and functional recovery, it is critical to selectively guide neural stem/progenitor cells (NSPCs) to differentiate into neurons and oligodendrocytes rather than astrocytes. Biomaterial scaffolds with specific properties such as electroconductivity can boost this event and guide the specific differentiation of NSPCs. Here, we prepared electroconductive and mechano-competent scaffolds made of shape-memory polyurethane‐polycaprolactone (PUCL) nanofibers and carbon nanotubes (CNTs) (namely, PUCL@CNT). The CNT-decorated PUCL platforms provided excellent shape-formable and shape-memorable properties for surgical compatibility as well as electroconductivity (∼ 8 S/m) and nanoscale-topography (tens-of-nm), which could promote the initial cell adhesion via the integrin-mediated focal adhesion signaling pathway, and promote neuron and oligodendrocyte differentiation. The potential mechanism of this lineage-specific differentiation of NSPCs upon the PUCL@CNT was evaluated by transcriptome sequencing analysis and pharmacological intervention tests, revealing the involvement of the intracellular calcium levels and the FAK-AKT-β-catenin pathway. When implanted in a rat corticectomy model, PUCL@CNT could induce a larger number of endogenous neural stem cells (both Nestin+ and β-catenin+) and neurons (Tuj1+) near the injured region (vs. PUCL and PBS), demonstrating the in vivo therapeutic role of PUCL@CNT. Taken together, the CNT surface-decoration was effective in driving NSPCs toward neuronal specification and their maturation, and the PUCL@CNT scaffold is potentially useful for neural tissue regeneration that can benefit via the neuronal activation of endogenous NSPCs.

Abstract 1327: Mechanism of tumor microenvironment remodeling and progression based on FAM20C-mediated extracellular kinome network in oral squamous cell carcinoma

Abstract Tumorigenesis and tumor growth are accomplished through the crosstalk between intra- and extracellular molecules, which is often mediated by phosphorylation, and research on intracellular signal transduction has made great progress. Despite the significance of the tumor microenvironment (TME) for tumor progression, relatively few kinome studies have been conducted on phosphorylation cascade in the TME of oral squamous cell carcinoma (OSCC). OSCC is an aggressive cancer with a high recurrence rate of 40-60%, but there are uncertain molecular classification and no identifiable driver mutation genes to be a druggable target. As the presence of extranodal extension (ENE) is currently the most significant risk factor for locoregional recurrence or distant metastasis, differences in molecular profiles between patients with and without ENE may provide insight into regulatory mechanisms that are critical for the recurrence and progression of OSCC. Using LC-MS-based secretome analysis, we examined total and phosphoproteins from ten patients' plasma with or without ENE. Global proteome analysis revealed that the ENE group had higher levels of protein phosphorylation, the ERK 1/2 cascade, signal transduction, phagocytosis, and the integrin-mediated signaling pathway than the without ENE group. Furthermore, 319 phosphosites originating from 165 proteins were discovered, with the majority of phosphorylated proteins having lipid binding, complement system, extracellular matrix, and calcium binding. Interestingly, we discovered 82 proteins with Ser-x-Glu/pSer sites among the phosphorylated proteins, indicating that they could be substrates of the unique extracellular secreted serine kinase, family with sequence similarity 20C (FAM20C). Proteins associated to tumor metastasis, such as insulin-like growth factor-binding proteins (IGFBPs), osteopontin (OPN), and serine protease inhibitors (Serpins), are known as substrates for the FAM20C. In accordance with the proteome results in plasma, gene ontology (GO) term analysis using the NanoString oncology panel revealed that extracellular structure organization-related genes were up-regulated and enzyme inhibitor, kinase regulator, and protein tyrosine kinase activity-related genes were down-regulated in human OSCC cell line, Cal-27, with knockout of FAM20C. Furthermore, we functionally demonstrated that FAM20C depletion inhibited invasion by lowering protein production of Vimentin, TGF-β, and ERK phosphorylation. Collectively, we discovered that the secreted kinase FAM20C controls metastasis by cross-talking with proteins in the TME and propose that this may be the evidence for OSCC prognosis. (This research was supported by National Cancer Center, Korea (No. 2210980) and National Research Foundation of Korea grant funded by the Korea government (No. 2020M3A9A5036362)). Citation Format: Mi Rim Lee, Yu-Sun Lee, Sumin Kang, Hye Won Shon, Jeong Eun Gong, Hye Joo Park, Jung-Ah Hwang, Kyung-Hee Kim, Sung Weon Choi, Yun-Hee Kim. Mechanism of tumor microenvironment remodeling and progression based on FAM20C-mediated extracellular kinome network in oral squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1327.

DOP32 Crohn’s disease stricture matrisome analysis reveals the anti-fibrotic activity of milk-fat globule-epidermal growth factor 8 (MFGE8)

Abstract Background Intestinal fibrosis is considered an inevitable consequence of chronic inflammatory bowel disease (IBD), leading to stricture formation and need for surgery. During the process of fibrogenesis, extracellular matrix (ECM) components critically regulate the function of mesenchymal cells. We characterized the composition and function of the ECM in fibrostenosing Crohn’s disease (CD) and control tissues. Methods Decellularized full thickness intestinal tissue platforms were tested using three different protocols and ECM composition in different tissue phenotypes was explored by proteomics and validated by quantitative polymerase chain reaction (qPCR) and immunohistochemistry. Primary human intestinal myofibroblasts (HIMF) treated with Milk Fat Globule-Epidermal growth factor 8 (MFGE8) were evaluated regarding mechanism of their anti-fibrotic response, and the action of MFGE8 was tested in experimental intestinal fibrosis. Results We established and validated an optimal decellularization protocol for intestinal IBD tissues. Matrisome analysis revealed elevated MFGE8 expression in CD strictured tissue (CDs), which was confirmed at the mRNA and protein levels. Treatment with MFGE8 inhibited ECM production in normal control (NL) HIMF but not CDs HIMF. Next generation sequencing (NGS) uncovered functionally relevant integrin-mediated signaling pathways, and blockade of integrin αvβ5 and focal adhesion kinase rendered HIMF non-responsive to MFGE8. MFGE8 prevented and reversed experimental intestinal fibrosis in vitro and in vivo. Conclusion MFGE8 displays anti-fibrotic effects, and its administration may represent a future therapeutic approach for prevention of IBD-induced intestinal strictures.

Bioinformatics analysis of the potential regulatory mechanisms of renal fibrosis and the screening and identification of factors related to human renal fibrosis.

BackgroundThis paper aimed to identify the key genes and potential mechanisms of renal fibrosis, and provide methods of evaluation and new ideas for the early diagnosis and treatment of renal fibrosis.MethodsThe GSE102515 dataset was searched from the Gene Expression Omnibus (GEO) database was searched, the differential genes were screened out, and the down-regulated and up-regulated genes were identified. Enrichment analysis of differential genes in the development of renal fibrosis was carried out using the DAVID database, differential genes were analyzed using the STRING database, and Cytoscape software was used for visual processing.ResultsEighteen up-regulated genes and ten down-regulated genes were screened. Differential genes are mainly involved in the integrin-mediated signaling pathway and mitotic sister chromatid binding, etc. We found that the molecular functions (MFs) of the differential genes are phospholipid binding and regulatory region DNA binding, etc. Moreover, the cellular components (CCs) of the differential genes are mainly related to low-density lipoprotein (LDL) particles and nuclei. Screening revealed that ADM, ARRB1, AVPR2, CCR1, MTNR1A, PTH, and S1PR2 were core genes in the interaction network of renal fibrosis risk-related proteins.ConclusionsIn this study, the differential genes in the occurrence of renal fibrosis were screened out via dataset analysis. It was found that ADM, ARRB1, AVPR2, CCR1, MTNR1A, PTH, and S1PR2 may be important participants in the development of renal fibrosis, which provides analytical support for the identification of valuable markers of renal fibrosis.

Low expression of integrin signaling pathway genes is associated with abdominal aortic aneurysm: a bioinformatic analysis by WGCNA.

An abdominal aortic aneurysm (AAA) is a potentially fatal disease associated with a high risk of rupture. AAA is pathologically distinguished by atherosclerotic thrombosis, immune cell infiltration, smooth muscle cell apoptosis, and extracellular matrix degradation. Given that there are no effective target treatments, once ruptured, AAA leads to high mortality with few long-term survivors. The goal of this study is to identify novel key pathways and hub genes involved in AAA formation with the aim of providing promising therapeutic targets for AAA. The transcriptome sequencing matrix of GSE47472 and GSE57691 were obtained from the GEO database. These datasets were further merged for differential expression analysis, weighted gene co-expression network analysis (WGCNA), and functional enrichment analysis in R (v4.0.2). A co-expression network was constructed with Cytoscape (v3.8.0) to generate the top 30 hub genes. Hub Genes with high clinical traits and potential values were further verified using a receiver operating characteristic (ROC) curve and qPCR analysis. A total of 745 differentially expressed genes were screened and 14 gene co-expression modules were established. Among these 14 modules, pink modules with a total of 118 genes showed the strongest correlation with AAA pathogenesis. Subsequently, 78 genes associated with a highly relevant clinical trait and the top 30 hub genes were intersected to generate 22 genes. Gene ontology functional enrichment analysis of the 22 genes revealed abnormal expression of genes relating to cell-matrix adhesion and integrin-mediated signaling pathway. LAMA5, ITGA8, ITGA1, and FERMT2 were associated with the integrin-mediated signaling pathway and cell-matrix adhesion while ACTN1 and CX3CL1 were simply associated with the latter. Low expressions of LAMA5, ACTN1, ITGA8, ITGA1, and FERMT2 were further verified through qPCR in a mouse model of AAA. Low expression of partial genes in the integrin signaling pathway was implicated in the function loss of mediated cell-matrix adhesion, which may offer novel targets for therapeutic intervention against AAA.

Placenta-specific 8 (PLAC8) mediates inflammation and mobility of the hPDLCs via MEK/ERK signaling pathway

BackgroundPlacenta-specific 8 (PLAC8) is reported to regulate cellular functions in the progression of various diseases. However, its role in periodontitis is still unclear. MethodsHuman periodontal ligament cells (hPDLCs) were treated with lipopolysaccharide of Porphyromonas Gingivalis (LPS-PG) to mimic periodontitis in vitro. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to measure the mRNA expression levels and western blot was for protein levels. Wound healing and transwell migration assays were performed to assess the cell mobility of hPDLCs. Both mRNA and protein levels of inflammatory cytokines including IFN-γ, IL-17, TNF-α, IL-4, IL-10 and IL-13 were accessed to evaluated process of periodontitis in vitro. Furthermore, the protein expressions of mitogen-activated protein kinase kinase (MEK), extracellular regulated protein kinase (ERK) and their phosphorylated products quantified by western blotting assay were determined to confirm the activation of the MEK/ERK signaling pathway. ResultsThe microarray analysis results showed that PLAC8 was most significantly downregulated in periodontium samples of patients with periodontitis, which participates in blood coagulation and integrin-mediated signaling pathway. PLAC8 was also markedly downregulated in the LPS-PG-treated hPDLCs. Moreover, overexpression of PLAC8 ameliorated inflammation and promoted cell mobility of LPS-PG-treated hPDLCs, while inhibition of PLAC8 exhibited the opposite effects. MEK/ERK was selected based on analyses of the protein-protein interaction (PPI) network as the potential signaling pathway interacted with PLAC8, and PLAC8 showed regulatory function on activation of the MEK/ERK pathway. Additionally, U0126, the inhibitor of MEK, abrogated the effects of PLAC8 on inflammation and cell mobility of LPS-PG-treated hPDLCs. ConclusionOverexpression of PLAC8 protected hPDLCs from dysfunction of inflammation and cell mobility via activating MEK/ERK pathway, indicating a novel therapeutic target for periodontitis.

Genetic interaction study of Alzheimer's disease quantitative biomarkers: A polygenic risk score analysis and evaluation.

Relationship between genetic factors and pathological features of Alzheimer's disease (AD) may be studied with biomarker, using both polygenic risk scores (PRSs), as well as individual genetic variants in genome-wide association studies (GWAS). In the Swedish BioFINDER study, we used a priori PRS for AD based on findings in recent GWAS, and AD related biomarkers in cerebrospinal fluid (CSF) in cognitively unimpaired individuals (n = 751), Mild Cognitive Impairment (n = 212), and AD (n = 150) patients. AD related biomarkers were rank-based inverse normal transformed to be used as dependent variables in linear regression models adjusted for age, gender, education, APOE ε4, ε2 count and significant principal components. We also tested individual genetic variants in GWAS for each biomarker. Analyses were performed in the total sample, and after stratification on MMSE results. The PRS was associated with higher CSF P-tau 181 (p ≤1.2e-05) and T-tau (p ≤ 8.14e-05) and lower CSF Aβ42/40 (p ≤ 0.006) and Aβ42 (p ≤ 0.04) (Figure 1, 2). Gene Enrichment of PRS 5 genes [containing 1850 genetic variants mapped to 1607 genes] for Tau biomarker showed 13 Gene Ontology (GO) Biological Process (BP) terms at p-value < e-03 ("Dendrite Morphogenesis": top hit; p-value ≤ 9.20e-06) and 16 KEGG pathway term enriched for genes of PRS 5 ("Phosphatidylinositol signaling system": top hit; p-value ≤ 5.5e-06) (Figure 3, 4). Gene enrichment of PRS 7 [containing 62 genetic variants mapped to 58 genes] for Aβ biomarker returned 12 GO terms ("Integrin-Mediated Signaling Pathway": top hit; p-value ≤1.20e-03) and 1 term enriched for KEGG pathway (Hematopoietic cell lineage). In our predefined list of genes interacting with MAPT (22 genes) and APP (69 genes) we found 3 genes from MAPT and APP set that were involved in PRS 5 and PRS 7 respectively. We also found 9 genes from APP set that was involved in PRS 5. Elevated levels of AD related biomarkers are associated with polygenic risk scores in AD. These findings further strengthens the link between genetic and biomarker disease predictors and indicate a potential role for these markers in disease prediction and patient stratification in AD.

Whole-exome sequencing reveals novel candidate single nucleotide variations for preventing adverse effects of levonorgestrel implantation.

Aim: To identify novel genes associated with adverse effects of levonorgestrel (LNG) implants based on comparative whole-exome sequencing. Materials & methods: A cohort comprising 104 participants, including 52 controls and 52 women with LNG-related adverse effects, was recruited. Seven cases and eight controls were selected for whole-exome sequencing. We verified 13 single nucleotide variations (SNVs) related with integrin-mediated signaling pathway and cell proliferation using the MassARRAY platform. Results: Finally, we screened 49 cases and 52 controls for analyses. Two SNVs (rs7255721 and rs1042522) were located in ADAMTS10 and TP53, respectively, and significantly different between two groups. These two SNVs lead to changes in protein structure and physicochemical parameters. Conclusion: Here, we defined two pathogenic mutations related to adverse LNG effects.

S1426 Identification of Three Upregulated Genes in Tumor Tissues With Poor Prognosis in Gastric Cancer via Bioinformatical Analysis

Introduction: The purpose of the present academic work was to identify genes with worse prognoses of gastric cancer (GC). Methods: GSE54129 & GSE64951 were extracted from GEO database. Differentially expressed genes (DEGs) between GC and normal specimen were identified via GEO2R online tools with logFC > 1 and adjust P value < 0.05. Raw data were checked in Venn software online to detect the common DEGs. The DEGs with logFC > 1 were considered as up-regulated genes. Gene ontology (GO) analysis and KEGG pathway analysis were conducted and visualized via DAVID and Bioinformatics online tool. PPI network was evaluated by STRING and hub genes were selected via CytoHubba app in Cytoscape. Kaplan Meier-plotter was used to conduct survival analysis. GEPIA website was used to analyze the expression. The best discriminate cut-off points between the high and low expression groups were assessed with the Receiver operating characteristic (ROC) curve and area under the curve (AUC) for overexpressed DEGs by using R software with pROC and ggplot2 packages to analyze data from TCGA-STAD with Log2 transformed FPKM. Results: There are 174 GC & 52 normal tissue samples in the two profile datasets, and 605 and 1,860 up-regulated DEGs from GSE64951 and GSE54129, respectively. Venn diagram detected 62 commonly up-regulated DEGs. GO analysis indicated that they were enriched in integrin-mediated signaling pathway, extracellular matrix organization, and collagen fibril organization for biological processes (BP), and enriched in integrin complex, integrin alpha1-beta1 complex, and endoplasmic reticulum lumen for GO cell component (CC), and enriched in cell adhesion molecule binding, collagen-binding involved in cell-matrix adhesion, and transcription corepressor activity for molecular function (MF). KEGG analysis found that they were enriched in Axon guidance, Cell adhesion molecules (CAMs), and Leishmaniasis. Analysis of PPI network complex found top 10 genes as shown in the PPI network figure. Kaplan Meier plotter identified 3core genes (COL5A1, COL12A1, ITGBL1) associated with a worse prognosis (P < 0.05), and GEPIA found a higher expression level of them in GC tissues than normal tissue. ROC curve showed that AUC of COL5A1, COL12A1, ITGBL1 were 0.813, 0.831, and 0.646, respectively, and their cutoff values were 4.494, 2.789, and 0.900. Conclusion: In GC, COL5A1, COL12A1, and ITGBL1 are associated with poor prognoses that could be potential therapeutic targets., COL5A1 and COL12A1 could be potential diagnostic markers.Figure 1.: A) PRISMA flow chart; B) Forest plot of the overall results; C) Funnel Plot.

Regulation of Myogenic Differentiation by Topologically Microgrooved Surfaces for Skeletal Muscle Tissue Engineering.

Inspired by the natural topological structure of skeletal muscle tissue, the topological surface construction of bionic scaffolds for skeletal muscle repair has attracted great interest. Many previous studies have focused on the effects of the topological structure on myoblasts. However, these studies used only specific repeating sizes and shapes to achieve the myoblast alignment and myotube formation; moreover, the regulatory effects of the size of a topological structure on myogenic differentiation are often neglected, leading to a lack of guidance for the design of scaffolds for skeletal muscle tissue engineering. In this study, we fabricated a series of microgroove topographies with various widths and depths via a combination of soft lithography and melt-casting and studied their effects on the behaviors of skeletal muscle cells, especially myogenic differentiation, in detail. Microgrooved poly(lactic-co-glycolic acid) substrates were found to effectively regulate the proliferation, myogenic differentiation, and myotube formation of C2C12 cells, and the degree of myogenic differentiation was significantly dependent on signals in response to the size of the microgroove structure. Compared with their depth, the width of the microgroove structures can more strongly affect the myogenic differentiation of C2C12 cells, and the degree of myoblast differentiation was enhanced with increasing groove width. Microgroove structures with relatively large groove widths and small groove depths promoted the myogenic differentiation of C2C12 cells. In addition, the integrin-mediated focal adhesion kinase signaling pathway and MAPK signaling pathway were activated in cells in response to the external topological structure, and the size of the topological structure of the material surface effectively regulated the degree of the cellular response to the external topological structure. These results can guide the design of scaffolds for skeletal muscle tissue engineering and the construction of effective bionic scaffold surfaces for skeletal muscle regeneration.

DNMT1 Mediated CAHM Repression Promotes Glioma Invasion via SPAK/JNK Pathway.

Gliomas are the most common and fatal brain tumors worldwide. Abnormal DNA promoter methylation is an important mechanism for gene loss of tumor suppressors. A long non-coding RNA colorectal adenocarcinoma hypermethylated (CAHM) has been reported to be nearly deleted in glioblastomas (GBMs). Nevertheless, the roles of CAHM in gliomas remain unknown up to now. In the present study, 969 glioma samples downloaded from the CGGA and Gravendeel databases were included. We found that CAHM expression was correlated with glioma grades, molecular subtype, IDH mutation status, and 1q/19p codel status. In glioma cells, CAHM is hypermethylated by DNA methyltransferase1 (DNMT1) and the loss of CAHM expression could be reversed by 5-Aza-2'-deoxycytidine (5-Aza), a specific inhibitor of DNA methyltransferases. Besides, the expression of CAHM was negatively associated with overall survival in both primary and recurrent gliomas. Moreover, the result of Gene Ontology (GO) analysis suggested that CAHM participated in negatively regulating cell development, nervous system development, neurogenesis, and integrin-mediated signaling pathway. Overexpression of CAHM inhibited glioma cell proliferation, clone formation, and invasion. Further exploring results showed that CAHM overexpression suppressed glioma migration and invasion through SPAK/MAPK pathway. Collectively, this study disclosed that CAHM might be a suppressor in gliomas.

Agonist-Induced Signaling and Integrin-Mediated Function in Murine Platelets Is Distinctly Regulated By the α Isoform of the Catalytic Subunit of Protein Phosphatase 1

Platelet activation at the site of injury is promoted by agonist-induced inside-out and integrin αIIbβ3-initiated outside-in signaling. Our understanding of the agonist and integrin mediated signaling pathways has largely been driven by studies that have examined the role of protein kinases. As models of signal transduction have been refined to include protein phosphorylation and protein dephosphorylation events, the contribution of the protein phosphatases to platelet signaling and function have garnered fresh attention. This is particularly evident for the catalytic subunit of serine/threonine protein phosphatase 1 (PP1c), wherein, its role in platelet biology has been previously assessed with pharmacological agents like calyculin A and okadaic acid. Although such chemical inhibitors represent a useful tool, it lacks specificity to discriminate the different isoforms of PP1c. PP1cα represents a major platelet expressed isoform and its contribution to platelet function is not known. To explore the potential role of PP1cα isoform in platelet signaling, we generated a platelet specific PP1cα -/- mice by crossing the PP1cα floxed mice with a platelet factor 4 (PF4) cre mice. Immunoblotting studies from PP1cα -/- mice confirmed that PP1cα was lost in platelets but not in lymphocytes. A compensatory upregulation of the PP1cβ but not PP1cγ1 isoform was noticed in PP1cα -/- platelets. Loss of PP1cα decreased platelet aggregation and soluble fibrinogen binding to low dose thrombin, thromboxane analog and convulxin, suggesting that PP1cα promotes agonist-induced inside-out signaling. In contrast, PP1cα -/- platelets displayed enhanced adhesiveness to immobilized fibrinogen and increased fibrin clot retraction, processes that are dependent on integrin-mediated outside-in signaling. In a microfluidic perfusion system, whole blood from PP1cα -/- mice displayed increased thrombus formation on collagen. p38 mitogen activated protein kinase (MAPK) was activated in PP1cα -/- platelets, and p38 inhibitor blocked the increased integrin-mediated PP1cα -/- platelet functions. These observations suggest that PP1cα suppress integrin-mediated function in part by decreasing the activation of p38 MAPK. Thus, unlike the conclusion gathered from generic phosphatase inhibitors that PP1c promotes platelet function, our studies using a genetic approach indicate that PP1cα contributes to platelet signaling in a fashion that is specific to the mode of signaling. Specifically, PP1cα promotes platelet agonist-induced inside-out signaling and suppress integrin-mediated outside-in signaling. This observation suggests that chemical activators of PP1cα isoform could serve as a potential antithrombotic agent. DisclosuresNo relevant conflicts of interest to declare.

Transcriptome Alterations of Prospectively Isolated Bone Marrow Stromal Cells Provide Potential Cues to MGUS and Multiple Myeloma Pathobiology

Multiple myeloma (MM) is the second most common hematopoietic malignancy characterized by the clonal population of plasma cells that invade and destroy adjacent bone tissue. Monoclonal gammopathy of undetermined significance (MGUS) is the premalignant precursor of MM with 1% of patients progressing to MM every year. Although both MGUS and MM plasma cells depend on interactions with bone marrow stromal cells for their survival and growth, little is known about the exact mechanisms of this crosstalk and if specific genetic events in the stromal compartment are correlated with disease state.Primary bone marrow mesenchymal stromal cells (BMSC) are essential components of the hematopoietic microenvironment and they give rise to the hematopoietic stroma in vivo. We have previously reported the phenotype of the bona-fide stroma stem cells in human bone marrow (Li et al., Stem Cell Reports, 3(6):965-74, 2014), and surface marker expression profiling studies on primary lin-CD45-CD71-CD235a-CD31-CD271+ BMSC from patients with MM (n=5), MGUS (n=8) and healthy age-matched controls (n=7) demonstrated clear differences in the expression of signature MSC surface markers, such as CD146, CD105, CD106, CD230, CD51, CD73, and W5C5.Motivated by these striking findings we then went on to transcriptionally interrogate prospectively isolated primary BMSC from MGUS and MM patients using RNAseq. Primary lin-CD45-CD71-CD235a-CD31-CD271+ stromal stem cells from patients undergoing diagnostic bone marrow examination (n=43) and age-matched healthy donors (n=7) were isolated from aspirated bone marrow samples by FACS. Fifteen and five of these patients were diagnosed with MGUS and MM, respectively, and RNA was extracted from bulk sorted populations of primary MM-BMSC, MGUS-BMSC and control-BMSC. The SMART-Seq v4 Ultra Low Input RNA Kit for Sequencing was used for cDNA synthesis. Sequencing libraries were prepared using Nextera XT DNA Library Prep kit (Illumina) and run on a NextSeq500 system (Illumina) using the NextSeq 500/550 High Output Kit v2 (300 cycles).Unsupervised clustering of the data showed that MGUS-BMSC samples clustered partly with healthy controls, but partly also with MM-BMSC or as a distinct and completely separate cluster. Clearly, some MGUS-BMSC showed features of healthy donor BMSC and some exhibited already a transcriptome profile that was more similar to MM-BMSC. In the next step, we therefore restricted the analysis to those BMSC samples that clustered separately and thus represented the MGUS-, MM- and normal BMSC specific transcriptional profiles. Comparison of the transcription patterns of these three distinct groups (MGUS-BMSC, n=3; MM-BMSC, n=5; control-BMSC, n=5) showed that a total of 3,758 genes were differentially expressed between the three groups. Further clustering of the data into 16 non-overlapping subsets of differentially expressed gene groups showed intriguing expression patterns. In one cluster, 78 genes were downregulated only in the MGUS-BMSC group, whereas three clusters contained genes that were downregulated specifically in MM-BMSC, and two clusters showed genes that were upregulated in both, MGUS-BMSC and MM-BMSC compared to control-BMSC. GSEA analysis revealed enrichment of genes reported to be downregulated in MM plasma cells, genes involved in cell adhesion and angiogenesis as well as genes involved in osteoclast differentiation in MM-BMSC versus MGUS-BMSC. Furthermore, MM-BMSCs were enriched for genes involved in integrin-mediated signaling pathway, cell-adhesion, and growth factors and chemokines associated with MM support compared to both control-BMSC and MGUS-BMSC.Taken together, surface marker profiling of prospectively isolated BMSC identified marked differences between these important stromal elements in MGUS, MM, and normal bone marrow. RNAseq of the stroma stem cells identified genes that were specifically upregulated/suppressed in MM-BMSC compared to MGUS-BMSC and control-BMSC. These genes thus represent potential candidates that might be implicated in the disruption of normal stroma function, thus leading to disease development and progression. Accordingly, studies are underway to investigate the effects of selected genes on stroma-myeloma crosstalk (dys)function. DisclosuresNo relevant conflicts of interest to declare.

Enhanced osteogenic differentiation of mesenchymal stem cells on P(VDF‐TrFE) layer coated microelectrodes

Electrical stimulation has been proved to be critical to regulate cell behavior. But, cell behavior is also susceptible to multiple parameters of the adverse interferences such as surface current, electrochemical reaction products, and non-uniform compositions, which often occur during direct electric stimulation. To effectively prevent the adverse interferences, a novel piezoelectric poly(vinylidene fluoride-trfluoroethylene)(P(VDF-TrFE)) layer was designed to coat onto the indium tin oxide (ITO) planar microelectrode. We found the electrical stimulation was able to regulate the osteogenic differentiation of mesenchymal stem cells (MSCs) through calcium-mediated PKC signaling pathway. Meanwhile, the surface charge of the designed P(VDF-TrFE) coating layer could be easily controlled by the pre-polarization process, which was demonstrated to trigger integrin-mediated FAK signaling pathway, finally up-regulating the osteogenic differentiation of MSCs. Strikingly, the crosstalk in the downstream of the two signaling cascades further strengthened the ERK pathway activation for osteogenic differentiation of MSCs. This P(VDF-TrFE) layer coated electrical stimulation microelectrodes therefore provide a distinct strategy to manipulate multiple-elements of biomaterial surface to regulate stem cell fate commitment.

Application of a small molecule inhibitor screen approach to identify CXCR4 downstream signaling pathways that promote a mesenchymal and fulvestrant-resistant phenotype in breast cancer cells.

Chemokine receptor 4 (CXCR4) and its ligand stromal-derived factor 1 (SDF-1) have well-characterized functions in cancer metastasis; however, the specific mechanisms through which CXCR4 promotes a metastatic and drug-resistant phenotype remain widely unknown. The aim of the present study was to demonstrate the application of a phenotypic screening approach using a small molecule inhibitor library to identify potential CXCR4-mediated signaling pathways. The present study demonstrated a new application of the Published Kinase Inhibitor Set (PKIS), a library of small molecule inhibitors from diverse chemotype series with varying levels of selectivity, in a phenotypic medium-throughput screen to identify potential mechanisms to pursue. Crystal violet staining and brightfield microscopy were employed to evaluate relative cell survival and changes to cell morphology in the screens. ‘Hits’ or lead active compounds in the first screen were PKIS inhibitors that reversed mesenchymal morphologies in CXCR4-activated breast cancer cells without the COOH-terminal domain (MCF-7-CXCR4-ΔCTD) and in the phenotypically mesenchymal triple-negative breast cancer cells (MDA-MB-231, BT-549 and MDA-MB-157), used as positive controls. In a following screen, the phenotypic and cell viability screen was used with a positive control that was both morphologically mesenchymal and had acquired fulvestrant resistance. Compounds within the same chemotype series were identified that exhibited biological activity in the screens, the ‘active’ inhibitors, were compared with inactive compounds. Relative kinase activity was obtained using published datasets to discover candidate kinase targets responsible for CXCR4 activity. MAP4K4 and MINK reversed both the mesenchymal and drug-resistant phenotypes, NEK9 and DYRK2 only reversed the mesenchymal morphology, and kinases, including ROS, LCK, HCK and LTK, altered the fulvestrant-resistant phenotype. Oligoarray experiments revealed pathways affected in CXCR4-activated cells, and these pathways were compared with the present screening approach to validate our screening tool. The oligoarray approach identified the integrin-mediated, ephrin B-related, RhoA, RAC1 and ErbB signaling pathways to be upregulated in MCF-7-CXCR4-ΔCTD cells, with ephrin B signaling also identified in the PKIS phenotypic screen. The present screening tool may be used to discover potential mechanisms of targeted signaling pathways in solid cancers.