Mediator Of Migration Research Articles

Identification of potential biomarkers of leprosy: A study based on GEO datasets.

Leprosy has a high rate of cripplehood and lacks available early effective diagnosis methods for prevention and treatment, thus novel effective molecule markers are urgently required. In this study, we conducted bioinformatics analysis with leprosy and normal samples acquired from the GEO database(GSE84893, GSE74481, GSE17763, GSE16844 and GSE443). Through WGCNA analysis, 85 hub genes were screened(GS > 0.7 and MM > 0.8). Through DEG analysis, 82 up-regulated and 3 down-regulated genes were screened(|Log2FC| > 3 and FDR < 0.05). Then 49 intersection genes were considered as crucial and subjected to GO annotation, KEGG pathway and PPI analysis to determine the biological significance in the pathogenesis of leprosy. Finally, we identified a gene-pathway network, suggesting ITK, CD48, IL2RG, CCR5, FGR, JAK3, STAT1, LCK, PTPRC, CXCR4 can be used as biomarkers and these genes are active in 6 immune system pathways, including Chemokine signaling pathway, Th1 and Th2 cell differentiation, Th17 cell differentiation, T cell receptor signaling pathway, Natural killer cell mediated cytotoxicity and Leukocyte transendothelial migration. We identified 10 crucial gene markers and related important pathways that acted as essential components in the etiology of leprosy. Our study provides potential targets for diagnostic biomarkers and therapy of leprosy.

Cross‐border mobility, inequality and migration intermediaries: Labour migration from Nepal to Malaysia

AbstractThis article aims to contribute to labour recruitment policy by demonstrating the relations between cross‐border mobility and inequality through the lens of migration intermediaries. Drawing on thematic analysis of the MIDEQ project's in‐depth interviews with Nepalese labour migrants (n = 20) in Malaysia, this research reveals the range of migration intermediaries along the recruitment chain, and shows contradictory roles played by migration intermediaries: they help migrant workers access employment and other opportunities thus overcoming inequality in mobility, whilst simultaneously reproducing socio‐economic inequalities and the unequal power relations experienced by migrants. Hence, we identify a “middle space effect” that links migration processes with migration outcomes, reconstructing socio‐economic inequalities in mediated migration. We highlight the role of state policies regarding migration and labour in co‐producing such inequalities, and the embeddedness of middle space intermediaries in unequal global power dynamics, and we offer policy suggestions on regulation of labour recruitment and employment.

LncRNA CARMN suppresses EMT through inhibiting transcription of MMP2 activated by DHX9 in breast cancer.

Long non-coding RNAs (lncRNAs) have been shown to drive cancer progression. However, the function of lncRNAs and the underlying mechanism in early-stage breast cancer(BC) have rarely been investigated. Datasets of pre-invasive ductal carcinoma in situ (DCIS), invasive ductal BC (IDC) and normal breast tissue from TCGA and GEO databases were used to conduct bioinformatics analysis. LncRNA CARMN was identified as a tumor suppressor in early-stage BC and related to a better prognosis. CARMN over-expression inhibited MMP2 mediated migration and EMT in BC. Further analysis showed that CARMN was located in the nucleus and functioned as an enhancer RNA (eRNA) in mammary epithelial cell. Mechanically, CARMN binding protein DHX9 was identified by RNA pull-down and mass spectrometry (MS) assays and it also bound to the MMP2 promoter to activate its transcription. As a decoy, CARMN competitively bound to DHX9 and blocked MMP2 transcriptional activation, thereby inhibiting metastasis and EMT of BC cells. These findings reveal the important role of CARMN as a tumor suppressor in the metastasis and a potential biomarker for progression in early-stage BC.

Tumor-associated macrophage-derived exosomal miR-513b-5p is a target of jianpi yangzheng decoction for inhibiting gastric cancer

Ethnopharmacological relevanceJianpi Yangzheng decoction (JPYZ) possesses a potential anti-tumor activity in gastric cancer. However, potential effect of JPYZ on regulating tumor-associated macrophage (TAM)-derived exosomes to affect gastric cancer is still unclear. Aim of studyWe aimed to clarify the role of tumor-associated macrophage derived exosomes (TAM-exos) in invasive and metastasis of gastric cancer and the mechanism of JPYZ regulate TAM-exos against gastric cancer. Materials and methodsFlow cytometry was performed to demonstrate whether JPYZ involved in TAM polarization. After JPYZ treatment, TAM conditioned medium (TAM-CM)/TAM-exos were co-cultured with gastric cancer cells and were detected by wound healing and transwell assay. Transcriptome sequencing and bioinformatics analysis predicted the exosomal miRNA after JPYZ intervention in TAM. miRNA mimic and inhibitor were used to verify the effect of miRNA in exosomes on gastric cancer cells. Q-PCR and luciferase reporter assay were employed to clarify the targeting relationship between miRNA and target gene. Western blot assay detected the expression levels of epithelial-mesenchymal transition (EMT) markers and related signaling pathways proteins. ResultsWe firstly demonstrated that TAM-CM intervened by JPYZ significantly inhibited the invasion and migration of gastric cancer. Furthermore, exosomes in TAM supernatants play a key role in migration of gastric cancer. Meanwhile, transcriptome sequencing and q-PCR revealed that miR-513b-5p expression was significantly reduced in TAM-exos intervened by JPYZ. And miR-513b-5p in TAM aggravated TAM-exos mediated invasion and migration of gastric cancer cells, the inhibitor of miR-513b-5p reversed TAM-exos mediated promotion. Bioinformatics analysis and luciferase reporter assay confirmed that PTEN was a direct target of miR-513b-5p in gastric cancer. MiR-513b-5p inhibited PTEN to activate AKT/mTOR signaling pathway thus promoting gastric cancer invasion and metastasis in vivo and in vitro. Importantly, JPYZ inhibited TAM derived exosomal miR-513b-5p, and alleviated AKT/mTOR activation by PTEN depended manner in gastric cancer. ConclusionTAM-exos containing miR-513b-5p lead to gastric cancer invasion and migration. Our findings clarify a novel TAM-exos mechanism of JPYZ for inhibiting gastric cancer progression.

Exosomes from tannic acid-stimulated macrophages accelerate wound healing through miR-221-3p mediated fibroblasts migration by targeting CDKN1b

Tannic acid (TA) and its extraction were traditionally used for treatment of traumatic bleeding in China, and in the previous study we have demonstrated that TA could accelerate cutaneous wound healing in rats. We attempted to decipher the mechanism of TA in promoting wound healing. In this study, we found that TA could enhance the growth of macrophages and inhibit the release of inflammatory cytokines (IL-1β, IL-6, TNF-α, IL-8 and IL-10) through inhibition of NF-κB/JNK pathway. TA activated Erk1/2 pathway, leading to increased expressions of growth factors, bFGF and HGF. Scratch study revealed that TA did not directly regulate the migration function of fibroblasts, but could indirectly enhance fibroblasts migration by the supernatant of TA-treated macrophages. Transwell study further proved that TA stimulates macrophages to secrete exosomes enriched in miR-221-3p by activating the p53 signaling pathway, and the exosomes entered into the fibroblast cytoplasm and bound to 3’UTR of target gene CDKN1b which induced decreased expression level of CDKN1b, leading to promoting fibroblast migration. This study provided new insights into how TA accelerates wound healing in the inflammatory and proliferative phases of wound healing.

Mn(OAc)3-Mediated Unexpected Cycloannulative Sulfonyl Migration Cascade using (E)-β-Iodovinyl Sulfones and ortho-Alkynylphenols for Direct Synthesis of Chromene-Derived Vinyl Sulfones.

Cycloannulative sulfonyl migration has received much attention; however, a carbon-to-carbon sulfonyl group shift still needs to be discovered. We hereby report a base-mediated oxa-Michael addition-elimination of (E)-β-iodovinyl sulfones with ortho-alkynylphenols, followed by cycloisomerization and unique stereoselective sulfonyl migration in one-pot, is realized under the influence of Mn(OAc)3·2H2O. A broad range of vinyl sulfone-tethered chromenes were readily accessed in moderate to high yields with good functional group compatibility. Notably, the reaction was robust at the gram scale, and postsynthetic transformations were successfully uncovered. Moreover, plausible mechanistic pathways were rationalized on the basis of existing experimental results.

Isolation controls reestablishment mechanisms and post-drying community structure in an intermittent stream.

Biota in disturbance-prone landscapes have evolved a variety of strategies to persist long term, either locally (resistance) or by regional recolonization (resilience). Habitat fragmentation and isolation can limit the availability of recolonization pathways, and thus the dynamics of post-disturbance community reestablishment. However, empirical studies on how isolation may control the mechanisms that enable community recovery remain scarce. Here, we studied a pristine intermittent stream (Chalone Creek, Pinnacles National Park, California) to understand how isolation (distance from a perennial pool) alters invertebrate community recolonization after drying. We monitored benthic invertebrate reestablishment during the rewetting phase along a ~2-km gradient of isolation, using mesh traps that selected for specific recolonization pathways (i.e., drift, flying, swimming/crawling, and vertical migration from the hyporheic). We collected daily emigration samples, surveyed the reestablished benthic community after 6 weeks, and compared assemblages across trap types and sites. We found that isolation mediated migration dynamics by delaying peak vertical migration from the hyporheic by ca. 1 day on average per 250 m of dry streambed. The relative importance of reestablishment mechanisms varied longitudinally-with more resistance strategists (up to 99.3% of encountered individuals) in the upstream reaches, and increased drift and aerial dispersers in the more fragmented habitats (up to 17.2% and 18%, respectively). Resistance strategists persisting in the hyporheic dominated overall (88.2% of individuals, ranging 52.9%-99.3% across sites), but notably most of these organisms subsequently outmigrated downstream (85.6% on average, ranging 52.1%-96% across sites). Thus, contrary to conventional wisdom, resistance strategists largely contributed to downstream resilience as well as to local community recovery. Finally, increased isolation was associated with a general decrease in benthic invertebrate diversity, and up to a 3-fold increase in the relative abundance of drought-resistant stoneflies. Our results advance the notion that understanding spatial context is key to predicting post-disturbance community dynamics. Considering the interaction between disturbance and fragmentation may help inform conservation in ecosystems that are subject to novel environmental regimes.

The Association between IL10 rs1800896 A/G and rs1800871 T/C Polymorphisms and Cancer Susceptibility

Background: The significance of interleukin-10(IL-10) on the susceptibility of malignant tumor is one of the hot spots of current research. 1082A &gt; G (rs1800896) and -819C &gt; T (rs1800871) are two genetic variants of IL-10, and their effects on malignancy need to be further explored. Therefore, in order to further explore the relationship between IL-10 polymorphisms and cancer susceptibility and the role of IL-10 in the occurrence and development of malignant tumors, in this paper, we use of odds ratios (ORs), corresponding 95% confidence intervals (CIs), and in silico tools. analysis to study the relationship between the two. Furthermore, GSEA was used to analyze the expression of IL-10 in renal cell carcinoma, bladder cancer and prostate cancer. We conducted a systematic analysis of 50 controlled trials involving 15,418 cancer patients and 18,597 controls. The analysis showed that the -1082A&gt;G (rs1800896) and -819C&gt;T (rs1800871) polymorphism were associated with the risk of bladder cancer. GSEA showed that IL-10 was highly expressed through the Cytokine-Cytokine-receptor-interaction pathway, JSK-STAT-signaling pathway, Natural killer cell mediated cytotoxicity pathway and Leukocyte transendothelial migration pathway.

IP10 is a predictor of successful vaccine protection against paratuberculosis infection in sheep.

The cell mediated immune response and ability of immune cells to migrate to the site of infection are both key aspects of protection against many pathogens. Mycobacterium avium subsp. paratuberculosis (MAP) is an intracellular pathogen and the causative agent of paratuberculosis, a chronic wasting disease of ruminants. Current commercial vaccines for paratuberculosis reduce the occurrence of clinical disease but not all animals are protected from infection. Therefore, there is a need to understand the immune responses triggered by these vaccines at the site of infection, in circulating immune cells and their relationships to vaccine-mediated protection. The magnitude and location of gene expression related to the cell mediated immune response and cellular migration were studied in the ileum of sheep. In addition, longitudinal IP10 (also known as IP10) secretion by circulating immune cells was examined in the same sheep. Animals were grouped based on vaccination status (vaccinated vs non-vaccinated) and MAP exposure (experimentally exposed vs unexposed). Vaccination of unexposed sheep increased the expression of IP10, CCL5 and COR1c. Sheep that were successfully protected by vaccination (uninfected following experimental exposure) had significantly reduced expression of IP10 in the ileum at 12months post exposure compared to vaccine non-responders (those that became infected) and non-vaccinated infected sheep. Successfully protected sheep also had significantly increased secretion of IP10 in in vitro stimulated immune cells from whole blood compared to vaccine non responders at 4months post exposure. Therefore, the IP10 recall response has the potential to be used as marker for infection status in vaccinated sheep and could be a biomarker for a DIVA test in sheep.

Intrinsic epigenetic control of angiogenesis in induced pluripotent stem cell-derived endothelium regulates vascular regeneration

Human-induced pluripotent stem cell-derived endothelial cells (iECs) provide opportunities to study vascular development and regeneration, develop cardiovascular therapeutics, and engineer model systems for drug screening. The differentiation and characterization of iECs are well established; however, the mechanisms governing their angiogenic phenotype remain unknown. Here, we aimed to determine the angiogenic phenotype of iECs and the regulatory mechanism controlling their regenerative capacity. In a comparative study with HUVECs, we show that iECs increased expression of vascular endothelial growth factor receptor 2 (VEGFR2) mediates their highly angiogenic phenotype via regulation of glycolysis enzymes, filopodia formation, VEGF mediated migration, and robust sprouting. We find that the elevated expression of VEGFR2 is epigenetically regulated via intrinsic acetylation of histone 3 at lysine 27 by histone acetyltransferase P300. Utilizing a zebrafish xenograft model, we demonstrate that the ability of iECs to promote the regeneration of the amputated fin can be modulated by P300 activity. These findings demonstrate how the innate epigenetic status of iECs regulates their phenotype with implications for their therapeutic potential.

Deacetylated Sialic Acids Increases Selectin‐binding in Lung Cancer Cells

Cancers utilize glycans to evade the immune system via the Sialic acid‐ Selectin pathway. Sialic acid specifically uses E‐ selectins, P‐ selectins, and L‐ selectins which each have different properties and preferred ligands. Here, we focused on modulating 9‐O and 7, 9‐O‐acetylation of Neu5Ac, via CRISPR‐ Cas9 gene editing, a functional group that is absent from Sias on many types of cancer cells. The two genes that are responsible for regulating the level of acetylation on Neu5Ac, are Sialic acid acetylesterase (SIAE) and Sialic acid acetyltransferase (CASD1). These genes modulated Selectin binding in lung cancer cells. In the absence of SIAE, Neu5Ac is acetylated, and binding of selectins is slightly increased whereas binding was greatly increased when the ability to acetylate was removed via CASD1 knock out. In addition to modulation Selectin binding, the absence of CASD1 knock out showed a greater expression of both PSGL‐1 (P‐selectin glycoprotein ligand) and Sialyl‐Lewisx. These glycans are essential ligands for P‐ and L‐ selectins, respectively. We are currently working on migration data to see how the modulation of Sialic acid contributes to the metastatic property of lung cancer. Uncovering how functional group alterations on Neu5Ac contribute mechanistically to both Selectin receptor binding, the Sialic Acid‐Selectin immune evasion pathway, Selectin‐receptor mediated migration, and the production of cancer‐associated selectin ligands—offers a promising avenue for targeted cancer immune therapies in the future.

Contribution of CD4+ T cell-mediated inflammation to diarrhea in patients with COVID-19

ObjectivesThis study aimed to explore the role of CD4+ T cells in the mechanisms of COVID-19 related diarrhea. MethodsWe analyzed lymphocyte subsets in patients with COVID-19 and the expression of angiotensin-converting enzyme 2 (ACE2), the transmembrane protease serine 2, and CD4+ T cell-related indicators in the colon were compared between patients with and without diarrhea. Correlation analyses were performed for ACE2 and other indicators to identify the relationship between SARS-CoV-2 infection and CD4+ mediated inflammation. The expression and distribution of CD4+ T cell-associated chemokines and their receptors were detected to determine the possibility of migration of CD4+ T cells to inflammation sites. ResultsThe CD4+ T cell counts and percentages and CD4/CD8 ratio showed the most significant differences between the 2 groups. The diarrhea group expressed higher levels of ACE2, T-box expressed in T cells (Tbet), and tumor necrosis factor-alpha (TNFα) at both the mRNA and protein levels, with no difference from the nondiarrhea group for the percentage of ACE2+TNFα+ cells, indicating an indirect association between ACE2 and TNFα. The mRNA expression of CXCL10, CXCL11, and CXCR3 and the number of CD4+CXCR3+T cells were increased in the diarrhea group. ConclusionsCD4+ T cell-mediated inflammation may contribute to COVID-19 related diarrhea. CXCR3+ mediated migration of CD4+ T cells into the gut may perpetuate inflammation.

In Vitro Characterization of Sphingosine 1-Phosphate Receptor 1 (S1P1) Expression and Mediated Migration of Primary Human T and B Cells in the Context of Cenerimod, a Novel, Selective S1P1 Receptor Modulator.

Cenerimod is a potent, selective sphingosine 1-phosphate receptor 1 (S1P1) modulator currently investigated in a Phase IIb study in patients with systemic lupus erythematosus (SLE) (NCT03742037). S1P1 receptor modulators sequester circulating lymphocytes within lymph nodes, thereby reducing pathogenic autoimmune cells (including T and B lymphocytes) in the bloodstream and inflamed tissues, making them an effective therapeutic concept for autoimmune disorders. Although the effect of S1P receptor modulators in reducing circulating lymphocytes is well documented, the precise molecular role of the S1P1 receptor on these cell types is not fully understood. In this study, the mode of action of cenerimod on human primary lymphocytes in different activation states was investigated focusing on their chemotactic behavior towards S1P in real-time, concomitant to S1P1 receptor expression and internalization dynamics. Here, we show that cenerimod effectively prevents T and B cell migration in a concentration-dependent manner. Interestingly, while T cell activation led to strong S1P1 re-expression and enhanced migration; in B cells, an enhanced migration capacity and S1P1 receptor surface expression was observed in an unstimulated state. Importantly, concomitant treatment with glucocorticoids (GCs), a frequently used treatment for autoimmune disorders, had no impact on the inhibitory activity of cenerimod on lymphocytes.

Abstract 10451: A Potential Therapeutic Antibody to Induce Collateral Formation in Cardiovascular Diseases

Introduction: Lack of efficient collateralisation during vascular occlusion leads to tissue ischemia in coronary, peripheral and cerebrovascular disease. Patients with peripheral, coronary, and cerebrovascular disease have elevated levels of the anti-angiogenic isoform of VEGF (VEGF-A 165 b), which correlate with poorer outcomes. In experimental animals, VEGF-A 165 b neutralisation improves blood flow and collateralisation after femoral or coronary artery ligation. Hypothesis: We tested the hypothesis that a potent, high affinity, humanised neutralising antibody to VEGF-A 165 b could have therapeutic potential in models of cardiovascular disease. Methods: A mouse monoclonal antibody to VEGF-A 165 b was humanised by cloning and site directed mutagenesis. Multiple clones were screened, and one with high affinity (measured by biolayer interferometry) was amplified. The efficacy in vitro was tested using endothelial cell migration assays and in vivo using the hindlimb ischemia (HLI) model in C57Bl6 mice fed a high fat high sucrose (HFHS) diet, and in Zucker Diabetic Fatty rats. Results: One clone (HC4LC2) had a VEGF-A 165 b affinity of 600pM. 0.3μg/ml of this clone reversed the inhibitory effect of recombinant human VEGF-A 165 b (31±4%, N=6 of VEGF-A 165 a alone) on migration of endothelial cells to 40ng/ml rhVEGF-A 165 a (89±9% N=3). Human monocyte dependent inhibition of VEGF-A 165 a mediated migration was dose dependently reversed by HC4LC2 (EC50, 55ng/ml, N=9 per concentration). HLI in HFHS mice impaired blood flow after 28 days in IgG treated mice (70±7.7% of pre-ischemic blood flow, N=6), which was restored to normal (93.3±5.5, p&lt;0.05, N=8) by intraperitoneal injection of 1mg/kg HC4LC2. Blood flow recovery after HLI was also seen in ZDF rats treated with HC4LC2 (106±16% of pre-ischemic flow, N=5) compared with IgG treated animals (76±.9%, N=5, p&lt;0.05, two-way ANOVA, all values mean ±SEM). Conclusions: These results indicate that HC4LC2 is a humanised, high affinity neutralising antibody to VEGF-A 165 b that could have therapeutic potential for patients with cardiovascular disease, by enhancing collateral formation.

ICAM-1 and ICAM-2 Are Differentially Expressed and Up-Regulated on Inflamed Pulmonary Epithelium, but Neither ICAM-2 nor LFA-1: ICAM-1 Are Required for Neutrophil Migration Into the Airways In Vivo.

Neutrophil migration into the airways is an important process to fight infection and is mediated by cell adhesion molecules. The intercellular adhesion molecules, ICAM-1 (CD54) and ICAM-2 (CD102) are known ligands for the neutrophil integrins, lymphocyte function associated antigen (LFA)-1 (αLβ2; CD11a/CD18), and macrophage-1 antigen (Mac-1;αMβ2;CD11b/CD18) and are implicated in leukocyte migration into the lung. However, it is ill-defined how neutrophils exit the lung and the role for ICAMs in trans-epithelial migration (TEpM) across the bronchial or alveolar epithelium. We found that human and murine alveolar epithelium expressed ICAM-1, whilst the bronchial epithelium expressed ICAM-2, and both were up-regulated during inflammatory stimulation in vitro and in inflammatory lung diseases such as cystic fibrosis. Although β2 integrins interacting with ICAM-1 and -2 mediated neutrophil migration across human bronchial epithelium in vitro, neither ICAM-2 nor LFA-1 binding of ICAM-1 mediated murine neutrophil migration into the lung or broncho-alveolar space during LPS-induced inflammation in vivo. Furthermore, TEpM of neutrophils themselves resulted in increased epithelial junctional permeability and reduced barrier function in vitro. This suggests that although β2 integrins interacting with ICAMs may regulate low levels of neutrophil traffic in healthy lung or early in inflammation when the epithelial barrier is intact; these interactions may be redundant later in inflammation when epithelial junctions are disrupted and no longer limit TEpM.

Inhibition of LOXL1-AS1 alleviates oxidative low-density lipoprotein induced angiogenesis via downregulation of miR-590-5p mediated KLF6/VEGF signaling pathway

ABSTRACT Increasing evidences have confirmed that long non-coding RNA LOXL1-AS1 functions in multiple human diseases. Here, we aim to explore the function and mechanism of LOXL1-AS1 in modulating oxidized low-density lipoprotein (ox-LDL)-induced angiogenesis of endothelial cells (ECs). Presently, we found that LOXL1-AS1 and KLF6 were upregulated in ECs treated by Ox-LDL in a dose- and time-dependent manner while miR-590-5p was downregulated. Overexpression of LOXL1-AS1 aggravated Ox-LDL mediated ECs proliferation and migration, and promoted angiogenesis both in vitro and in vivo. On the contrary, enhancing miR-590-5p or inhibiting LOXL1-AS1 level led to suppressive effects on the proliferation, migration and angiogenesis of ECs. Moreover, LOXL1-AS1 upregulation promoted the expression of vascular endothelial growth factor (VEGF), MMPs (including MMP2, MMP9, and MMP14) and also activated VEGF/VEGFR2/PI3K/Akt/eNOS pathway. Mechanistically, LOXL1-AS1 works as a competitive endogenous RNA (ceRNA) by sponging miR-590-5p, which targeted at the 3ʹ-untranslated region (3ʹUTR) of KLF6. Additionally, the proliferation, migration, and angiogenesis of ECs were elevated following KLF6 upregulation. By detecting the expression of LOXL1-AS1 and miR-590-5p in the serum of healthy donors and atherosclerosis patients, it was found that LOXL1-AS1 was upregulated in atherosclerosis patients (compared with healthy donors) and had a negative relationship with miR-590-5p. Taken together, LOXL1-AS1 promoted Ox-LDL induced angiogenesis via regulating miR-590-5p-modulated KLF6/VEGF signaling pathway. The LOXL1-AS1-miR-590-5p axis exerts a novel role in the progression of atherosclerosis.

Inhibition of LOXL1-AS1 alleviates oxidative low-density lipoprotein induced angiogenesis via downregulation of miR-590-5p mediated KLF6/VEGF signaling pathway

ABSTRACT Increasing evidences have confirmed that long non-coding RNA LOXL1-AS1 functions in multiple human diseases. Here, we aim to explore the function and mechanism of LOXL1-AS1 in modulating oxidized low-density lipoprotein (ox-LDL)-induced angiogenesis of endothelial cells (ECs). Presently, we found that LOXL1-AS1 and KLF6 were upregulated in ECs treated by Ox-LDL in a dose- and time-dependent manner while miR-590-5p was downregulated. Overexpression of LOXL1-AS1 aggravated Ox-LDL mediated ECs proliferation and migration, and promoted angiogenesis both in vitro and in vivo. On the contrary, enhancing miR-590-5p or inhibiting LOXL1-AS1 level led to suppressive effects on the proliferation, migration and angiogenesis of ECs. Moreover, LOXL1-AS1 upregulation promoted the expression of vascular endothelial growth factor (VEGF), MMPs (including MMP2, MMP9 and MMP14) and also activated VEGF/VEGFR2/PI3K/Akt/eNOS pathway. Mechanistically, LOXL1-AS1 works as a competitive endogenous RNA (ceRNA) by sponging miR-590-5p, which targeted at the 3ʹ-untranslated region (3ʹUTR) of KLF6. Additionally, the proliferation, migration and angiogenesis of ECs were elevated following KLF6 upregulation. By detecting the expression of LOXL1-AS1 and miR-590-5p in the serum of healthy donors and atherosclerosis patients, it was found that LOXL1-AS1 was upregulated in atherosclerosis patients (compared with healthy donors) and had a negative relationship with miR-590-5p. Taken together, LOXL1-AS1 promoted Ox-LDL induced angiogenesis via regulating miR-590-5p-modulated KLF6/VEGF signaling pathway. The LOXL1-AS1-miR-590-5p axis exerts a novel role in the progression of atherosclerosis.

PD-L1 reverse signaling in dermal dendritic cells promotes dendritic cell migration required for skin immunity.

Abstract While the function of the extracellular region of programmed death ligand 1 (PD-L1) through its interactions with PD-1 on T cells is well studied, little is understood regarding signaling via the intracellular domain of PD-L1, termed PD-L1 reverse signaling. The objective of this study is to determine how PD-L1 reverse signaling impacts dendritic cell (DC) function during immune responses. We outline a major role for PD-L1 reverse signaling in the control of DC migration from the skin to the draining lymph node (dLN). We find that total loss of PD-L1 on DCs impairs migration to the dLN following an innate immune stimulus. Using a mutant mouse model, we identify a TSS signaling motif within the intracellular domain of PD-L1. This TSS motif proves critical for promoting chemokine mediated DC migration to the dLN during inflammation. The loss of DC migration, in the PD-L1 TSS mutant, leads to a significant decline in T cell priming when DC trafficking is required for antigen delivery to the dLN. We found that the TSS motif is required for chemokine receptor signaling, and disruption of this motif impairs signaling downstream of the Gα subunit of the heterotrimeric G protein complex, leading to impairment in ERK phosphorylation and actin polymerization in DCs. Finally, we demonstrate that ligation of PD-L1 by one or more of the known binding partners of PD-L1, CD80 and PD-1, appears to support migration of DCs to the dLN. These studies identify a novel function for PD-L1 reverse signaling in supporting DC migration during initiation of immune responses, and raises questions about the potential impact of PD-L1 antibody blockade on DC function in patients with cancer.

CCL2‐ Dependent Macrophage Recruitment by Glioblastoma Stem Cells: The Role of Gα12 and YAP Signaling

Glioblastoma multiforme (GBM), the most malignant form of brain tumor, has an average survival rate of less than two years, associated with recurrence despite conventional interventions. GBM tumors contain myeloid cells, recruited in response to inflammatory cytokines which play a role in the tumor progression and may also contribute to immune suppression. Tumor associated macrophages interact with tumor cells and conversely tumor cells contribute to generation of the inflammatory immune cell environment. Gα12 protein-coupled receptors are regulated by inflammatory mediators often generated in the tumor cell environment. Stimulation of these receptors activates the transcriptional co-activator YAP (Yes-associated protein 1) which can in turn induce inflammatory gene expression. Our previous studies showed that knockdown of YAP in GSC-23 PDX cells significantly attenuated in vitro stemness, proliferation, and migration. In vivo experiments showed that YAP knockdown PDX cells formed significantly smaller tumors and had lower lethality than wild-type cells. Our more recent in vivo studies with GSC-23 cells suggested that there is a significant inflammatory response in the tumor cell environment. In order to determine if Gα12/YAP signaling in this glioma stem cell tumor line contributed to macrophage infiltration we utilized an in vitro. Transwell migration assay with human THP-1 macrophages on the top and GSC-23 cells on the bottom. Remarkably, the presence of GSC-23 cells strongly enhanced THP-1 cell migration and this could be mimicked almost fully by replacing the cells with medium in which they were cultured for 24 hours. One of the most efficacious mediators of macrophage migration is CCL2 (MCP-1). The involvement of CCL2 and its receptor CCR2 on THP-1 cell migration was demonstrated by the ability of the CCR2 blocker RS102895 to significantly inhibit the migratory response elicited by GSC-23 cells or cell medium. To understand whether the generation of CCL2 and thus the effect of the tumor cells on macrophage recruitment was specifically regulated, we examined GSC-23 cells in which YAP or Gα12 were deleted. YAP knockout prevented GSC-23 cell mediated migration suggesting that YAP regulates production of CCL2 by the GSC-23 cells. We observed that CCL2 mRNA levels were in fact significantly lower in YAP knockdown compared to WT cells. Notably this appeared to depend on the presence of the THP-1 cells suggesting that macrophage crosstalk to the GSC-23 tumor cells controls CCL2 generation. IL-6 mRNA levels were similarly regulated by THP-1 signaling to GSC-23 cells through YAP. Using a Gliovis tool to analyze data sets of GBM tumors, we determined that there is a highly significant Pearson's correlation between YAP1 and CCL2 gene expression as well as a correlation between YAP1 and IL-6 expression. Further of studies are underway to explore mechanisms responsible for this glioma stem cell /macrophages crosstalk in co-culture experiments. We suggest that YAP mediated cytokine generation by glioma stem cells represents a critical point for therapeutic intervention to disrupt recruitment of macrophages and interfere with their potential role in creating an immunosuppressive myeloid cell tumor microenvironment.

Long non-coding RNA EWSAT1 promoted metastasis and actin cytoskeleton changes via miR-24-3p sponging in osteosarcoma.

Non‐coding RNAs are closely associated with tumorigenesis in multiple malignant tumours, including osteosarcoma (OS). Long non‐coding RNA Ewing sarcoma‐associated transcript 1 (EWSAT1) plays a role in metastasis, and actin cytoskeletal changes in OS remain unclear. In the current study, we showed that EWSAT1 expression was up‐regulated in OS and that an elevation in the EWSAT1 expression level was correlated with poor prognosis in patients with OS. Functionally, we showed that knockdown of EWSAT1 suppressed migration and induced actin stress fibre degradation in MNNG/HOS and 143B cells. Moreover, we found that ROCK1 was a key downstream effector in EWSAT1‐mediated cell migration and actin stress fibre changes. Furthermore, we demonstrated that ROCK1 and EWSAT1 shared a similar microRNA response element of microRNA‐24‐3p (miR‐24‐3p). Moreover, we verified that miR‐24‐3p suppressed ROCK1 and its mediated migration and actin stress fibres change by direct targeting. EWSAT1 promoted ROCK1‐mediated migration and actin stress fibre formation through miR‐24‐3p sponging. Lastly, through an in vivo study, we demonstrated that EWSAT1 promoted lung metastasis in OS. According to the above‐mentioned results, we suggest that EWSAT1 acts as an oncogene and that EWSAT1/miR‐24‐3p/ROCK1 axial could be a new target in the treatment of OS.