Identification of diagnostic biomarks and immune cell infiltration in ulcerative colitis.

We aimed to explore diagnostic biomarks and immune cell infiltration characteristics in ulcerative colitis (UC). We used the dataset GSE38713 as the training set and dataset GSE94648 as the test set. A total of 402 differentially expressed genes (DEGs) were obtained from GSE38713. Annotating, visualizing, and integrating discovery of these differential genes was performed using Gene Ontology (GO), Kyoto Gene and Genome Encyclopedia Pathway (KEGG), and Gene Set Enrichment Analysis (GSEA). Protein-protein interaction networks were constructed from the STRING database, and protein functional modules were identified using the CytoHubba plugin of Cytoscape. Random forest and LASSO regression were used to screen for UC-related diagnostic markers, and ROC curves were generated to validate their diagnostic value. The composition of 22 immune cells was analyzed, and the immune cell infiltration in UC was analyzed using CIBERSORT. Results: Seven diagnostic markers associated with UC were identified: TLCD3A, KLF9, EFNA1, NAAA,WDR4, CKAP4, and CHRNA1. Immune cell infiltration assessment revealed that macrophages M1, activated dendritic cells, and neutrophil cells infiltrated relatively more compared to normal control samples. Our results suggest a new functional feature of UC and suggest potential biomarkers for UC through comprehensive analysis of integrated gene expression data.

Pharmacological characterization of second generation FXR agonists as effective EphA2 antagonists: A successful application of target hopping approach.

It is well demonstrated the key role of Eph-ephrin system, specifically of EphA2 receptor, in supporting tumor growth, invasion, metastasis and neovascularization. We previously identified FXR agonists as eligible antagonists of Eph-ephrin system. Herein we characterize new commercially available FXR (Farnesoid X Receptor) agonists as potential Eph ligands including Cilofexor, Nidufexor, Tropifexor, Turofexorate isopropyl and Vonafexor. Our exploration based on molecular modelling investigations and binding assays shows that Cilofexor binds specifically and reversibly to EphA2 receptor with a Ki value in the low micromolar range. Furthermore, Cilofexor interferes with the phosphorylation of EphA2 and the cell retraction and rounding in PC3 prostate cancer cells, both events depending on EphA2 activation. In conclusion, we can confirm that target hopping can be a successful approach to discover new moiety of protein-protein inhibitors.

The Functions of EphA1 Receptor Tyrosine Kinase in Several Tumors.

BACKGROUND: Eph receptors tyrosine kinase (RTK) were identified in 1987 from hepatocellular carcinoma cell lines and were the largest known subfamily of RTK. Eph receptors can be divided into two categories, EphA and EphB, based on their structure and receptor-ligand specificity. EphA can be divided into 10 species (EphA 1-10) and EphB into 6 species (EphB1-6). Similarly, the ligands of Eph receptors are Ephrins. Ephrins also can be divided into Ephrin A and Ephrin B, of which there are five species(Ephrin-A1-5) and three species(Ephrin-B1-3). Among the Eph receptors, EphA1 has been the least studied so far. As far as we know, Eph receptors are involved in multiple pathologies, including cancer progression, tumor angiogenesis, intestinal environmental stability, the lymph node system, neurological disease, and inhibition of nerve regeneration after injury. There is a link between EphA1, integrin and ECM- related signal pathways. Ephrin-A1 is a ligand of the EphA1 receptor. EphA1 and ephrin-A1 functions are related to tumor angiogenesis. EphA1 and ephrin-A1 also play roles in gynecological diseases. Ephrin-A1 and EphA1 receptors regulate the follicular formation, ovulation, embryo transport, implantation and placental formation, which are of great significance for the occurrence of gynecological tumor diseases. EphA1 has been identified as an oncoprotein in various tumors and has been associated with the prognosis of various tumors in recent years. EphA1 is considered a driver gene in tumor genomics. There are significant differences in EphA1 expression levels in different types of normal tissues and tumors and even in different stages of tumor development, suggesting its functional diversity. Changes at the gene level in cell biology are often used as biological indicators of cancer, known as biomarkers, which can be used to provide diagnostic or prognostic information and are valuable for improving the detection, monitoring and treatment of tumors. However, few prognostic markers can selectively predict clinically significant tumors with poor prognosis. These malignancies are more likely to progress and lead to death, requiring more aggressive treatment. Currently available treatments for advanced cancer are often ineffective, and treatment options are mainly palliative. Therefore, early identification and treatment of those at risk of developing malignant tumors are crucial. Although pieces of evidence have shown the role of EphA1 in tumorigenesis and development, its specific mechanism is still unknown to a great extent. OBJECTIVE: This review reveals the changes and roles of EphA1 in many tumors and cancers. The change of EphA1 expression can be used as a biological marker of cancer, which is valuable for improving tumor detection, monitoring and treatment and can be applied to imaging. Studies have shown that structural modification of EphA1 could make it an effective new drug. EphA1 is unique in that it can be considered a prognostic marker in many tumors and is of important meaning for clinical diagnosis and operative treatment. At the same time, the study of the specific mechanism of EphA1 in tumors can provide a new way for targeted therapy. METHODS: Relevant studies were retrieved and collected through the PubMed system. After determining EphA1 as the research object, by analyzing research articles on EphA1 in the PubMed system in recent 10 years, we found that EphA1 was closely connected with the occurrence and development of tumors and further determined the references according to the influencing factors for review and analysis. RESULTS: EphA1 has been identified as a cancer protein in various tumors, such as hepatocellular carcinoma, nasopharyngeal carcinoma, ovarian cancer, gastric cancer, colorectal cancer, clear cell renal cell carcinoma, esophageal squamous cell carcinoma, breast cancer, prostate cancer and uveal melanoma. EphA1 is abnormally expressed in these tumor cells, which mainly plays a role in cancer progression, tumor angiogenesis, intestinal environmental stability, the lymph node system, nervous system diseases and gynecological diseases. In a narrow sense, EphA1 is especially effective in breast cancer in terms of gynecological diseases. However, the specific mechanism of EphA1 leading to the change of cancer cells in some tumors is not clear, which needs further research and exploration. CONCLUSION: RTK EphA1 can be used as a biomarker for tumor diagnosis (especially a prognostic marker), an indispensable therapeutic target for new anti-tumor therapies, and a novel anti-tumor drug.

A genome-wide association study with tissue transcriptomics identifies genetic drivers for classic bladder exstrophy.

Classic bladder exstrophy represents the most severe end of all human congenital anomalies of the kidney and urinary tract and is associated with bladder cancer susceptibility. Previous genetic studies identified one locus to be involved in classic bladder exstrophy, but were limited to a restrict number of cohort. Here we show the largest classic bladder exstrophy genome-wide association analysis to date where we identify eight genome-wide significant loci, seven of which are novel. In these regions reside ten coding and four non-coding genes. Among the coding genes is EFNA1, strongly expressed in mouse embryonic genital tubercle, urethra, and primitive bladder. Re-sequence of EFNA1 in the investigated classic bladder exstrophy cohort of our study displays an enrichment of rare protein altering variants. We show that all coding genes are expressed and/or significantly regulated in both mouse and human embryonic developmental bladder stages. Furthermore, nine of the coding genes residing in the regions of genome-wide significance are differentially expressed in bladder cancers. Our data suggest genetic drivers for classic bladder exstrophy, as well as a possible role for these drivers to relevant bladder cancer susceptibility.

Single-Cell Transcriptomics of Endothelial Cells in Upper and Lower Human Esophageal Squamous Cell Carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a type of progressive and distant metastatic tumor. Targeting anti-angiogenic genes could effectively hinder ESCC development and metastasis, whereas ESCC locating on the upper or the lower esophagus showed different response to the same clinical treatment, suggesting ESCC location should be taken into account when exploring new therapeutic targets. In the current study, to find novel anti-angiogenic therapeutic targets, we identified endothelial cell subsets in upper and lower human ESCC using single-cell RNA sequencing (scRNA-seq), screened differentially expressed genes (DEGs), and performed gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The results showed that common DEGs shared in the upper and the lower endothelial cells mainly are involved in vessel development, angiogenesis, and cell motility of endothelial cells by regulating PI3K-AKT, Rap1, Ras, TGF-beta, and Apelin signaling pathways. The critical regulatory genes were identified as ITGB1, Col4A1, Col4A2, ITGA6, LAMA4, LAMB1, LAMC1, VWF, ITGA5, THBS1, PDGFB, PGF, RHOC, and CTNNB1. Cell metabolism-relevant genes, e.g., MGST3, PNP, UPP1, and HYAL2 might be the prospective therapeutic targets. Furthermore, we found that DEGs only in the upper endothelial cells, such as MAPK3, STAT3, RHOA, MAPK11, HIF1A, FGFR1, GNG5, GNB1, and ARHGEF12, mainly regulated cell adhesion, structure morphogenesis, and motility through Phospholipase D, Apelin, and VEGF signaling pathways. Moreover, DEGs only in the lower endothelial cells, for instance PLCG2, EFNA1, CALM1, and RALA, mainly regulated cell apoptosis and survival by targeting calcium ion transport through Rap1, Ras, cAMP, Phospholipase D, and Phosphatidylinositol signaling pathways. In addition, the upper endothelial cells showed significant functional diversity such as cytokine-responsive, migratory, and proliferative capacity, presenting a better angiogenic capacity and making it more sensitive to anti-angiogenic therapy compared with the lower endothelial cells. Our study has identified the potential targeted genes for anti-angiogenic therapy for both upper and lower ESCC, and further indicated that anti-angiogenic therapy might be more effective for upper ESCC, which still need to be further examined in the future.

Multiomics analysis reveals that hepatocyte nuclear factor 1ß regulates axon guidance genes in the developing mouse kidney.

The transcription factor hepatocyte nuclear factor 1ß (HNF-1ß) is essential for normal development of the kidney and other epithelial organs. In the developing mouse kidney, HNF-1ß is required for the differentiation and patterning of immature nephrons and branching morphogenesis of the ureteric bud (UB). Here, we used ChIP-sequencing (ChIP-seq) and RNA sequencing (RNA-seq) to identify genes that are regulated by HNF-1ß in embryonic mouse kidneys. ChIP-seq revealed that HNF-1ß binds to 8284 sites in chromatin from E14.5 mouse kidneys. Comparison with previous ATAC-seq and histone modification studies showed that HNF-1ß binding peaks colocalized with open chromatin and epigenetic marks of transcriptional activation (H3K27 acetylation, H3K4 trimethylation, H3K4 monomethylation), indicating that the binding sites were functional. To investigate the relationship between HNF-1ß binding and HNF-1ß-dependent gene regulation, RNA-seq was performed on UB cells purified from wild-type and HNF-1ß mutant embryonic kidneys. A total of 1632 genes showed reduced expression in HNF-1ß-deficient UB cells, and 485 genes contained nearby HNF-1ß binding sites indicating that they were directly activated by HNF-1ß. Conversely, HNF-1ß directly repressed the expression of 526 genes in the UB. Comparison with snATAC-seq analysis of UB-derived cells showed that both HNF-1ß-dependent activation and repression correlated with chromatin accessibility. Pathway analysis revealed that HNF-1ß binds near 68 axon guidance genes in the developing kidney. RNA-seq analysis showed that Nrp1, Sema3c, Sema3d, Sema6a, and Slit2 were activated by HNF-1ß, whereas Efna1, Epha3, Epha4, Epha7, Ntn4, Plxna2, Sema3a, Sema4b, Slit3, Srgap1, Unc5c and Unc5d were repressed by HNF-1ß. RNAscope in situ hybridization showed that Nrp1, Sema3c, Sema3d, Sema6a, and Slit2 were expressed in wild-type UB and were dysregulated in HNF-1ß mutant UB. These studies show that HNF-1ß directly regulates the expression of multiple axon guidance genes in the developing mouse kidney. Dysregulation of axon guidance genes may underlie kidney defects in HNF-1ß mutant mice.

Role of EFNA1 SNP (rs12904) in Tumorigenesis and Metastasis of Colorectal Cancer: A Bioinformatic Analysis and HRM SNP Genotyping Verification.

OBJECTIVE: Colorectal cancer is a prevalent disease with a poor prognosis and is known as a heterogeneous disease with many differences in clinical Symptoms and molecular profiles. The present study aimed to systematically evaluate the association of SNPs in miRNA binding sites of target genes that are involved in CRC angiogenesis, epithelial to mesenchymal transition, and cytoskeleton organization with tumorigenesis and metastasis of CRC. METHODS: A case-control study was performed on 146 samples of CRC patients and 132 healthy samples. After that, the DNA of all samples was isolated by the salting-out method. Finally, the genotypes for EFNA1 SNP (rs12904) were identified by HRM (High-resolution melting analysis) method. In order to evaluate the results of genotyping, two samples from each genotype were sequenced using the sanger sequencing method. RESULT: The frequency of AA genotype and the frequency of GG for rs12904 in satge4 and other stages are different from each other (P-value <0.0001) (P-value = 0.008). Also, the frequency of AA genotype in patients with different grades is different from each other (P-value = 0.035), while the frequency of AG   genotype and the frequency of GG   genotype is not significantly different in patients with different grades (P-value = 0.377) (P-value = 0.284). CONCLUSION: Results of this study indicated that patients carrying the GA and GG genotypes reduced the risk of disease progression compared to the AA genotype. As a result, this polymorphism plays a key role in CRC pathogenesis and metastasis and could be used as a biomarker in molecular diagnosis and metastatic state prediction in the near future after further study of its signaling pathways and molecular mechanism.

The efficacy of receptor tyrosine kinase EphA2 autophosphorylation increases with EphA2 oligomer size.

The receptor tyrosine kinase (RTK) EphA2 is expressed in epithelial and endothelial cells and controls the assembly of cell-cell junctions. EphA2 has also been implicated in many diseases, including cancer. Unlike most RTKs, which signal predominantly as dimers, EphA2 readily forms high-order oligomers upon ligand binding. Here, we investigated if a correlation exists between EphA2 signaling properties and the size of the EphA2 oligomers induced by multiple ligands, including the widely used ephrinA1-Fc ligand, the soluble monomeric m-ephrinA1, and novel engineered peptide ligands. We used fluorescence intensity fluctuation (FIF) spectrometry to characterize the EphA2 oligomer populations induced by the different ligands. Interestingly, we found that different monomeric and dimeric ligands induce EphA2 oligomers with widely different size distributions. Our comparison of FIF brightness distribution parameters and EphA2 signaling parameters reveals that the efficacy of EphA2 phosphorylation on tyrosine 588, an autophosphorylation response contributing to EphA2 activation, correlates with EphA2 mean oligomer size. However, we found that other characteristics, such as the efficacy of AKT inhibition and ligand bias coefficients, appear to be independent of EphA2 oligomer size. Taken together, this work highlights the utility of FIF in RTK signaling research and demonstrates a quantitative correlation between the architecture of EphA2 signaling complexes and signaling features.

H4 acetylation by the NuA4 complex is required for plastid transcription and chloroplast biogenesis.

Chloroplast biogenesis is crucial in plant development, as it is essential for the transition to autotrophic growth. This process is light-induced and relies on the orchestrated transcription of nuclear and plastid genes, enabling the effective assembly and regulation of the photosynthetic machinery. Here we reveal a new regulation level for this process by showing the involvement of chromatin remodelling in the nuclear control of plastid gene expression for proper chloroplast biogenesis and function. The two Arabidopsis homologues of yeast EPL1 protein, components of the NuA4 histone acetyltransferase complex, are essential for plastid transcription and correct chloroplast development and performance. We show that EPL1 proteins are light-regulated and necessary for concerted expression of nuclear genes encoding most components of chloroplast transcriptional machinery, directly mediating H4K5ac deposition at these loci and promoting the expression of plastid genes required for chloroplast biogenesis. These data unveil a NuA4-mediated mechanism regulating chloroplast biogenesis that links the transcription of nuclear and plastid genomes during chloroplast development.

Exosomal EPHA2 derived from highly metastatic breast cancer cells promotes angiogenesis by activating the AMPK signaling pathway through Ephrin A1-EPHA2 forward signaling.

Rationale: Angiogenesis is a fundamental process of tumorigenesis, growth, invasion and metastatic spread. Extracellular vesicles, especially exosomes, released by primary tumors promote angiogenesis and cancer progression. However, the mechanism underlying the pro-angiogenic potency of cancer cell-derived exosomes remains poorly understood. Methods: Exosomes were isolated from breast cancer cells with high metastatic potential (HM) and low metastatic potential (LM). The pro-angiogenic effects of these exosomes were evaluated by in vitro tube formation assays, wound healing assays, rat arterial ring budding assays and in vivo Matrigel plug assays. Subsequently, RNA sequencing, shRNA-mediated gene knockdown, overexpression of different EPHA2 mutants, and small-molecule inhibitors were used to analyze the angiogenesis-promoting effect of exosomal EPHA2 and its potential downstream mechanism. Finally, xenograft tumor models were established using tumor cells expressing different levels of EPHA2 to mimic the secretion of exosomes by tumor cells in vivo, and the metastasis of cancer cells were monitored using the IVIS Spectrum imaging system and Computed Tomography. Results: Herein, we demonstrated that exosomes produced by HM breast cancer cells can promote angiogenesis and metastasis. EPHA2 was rich in HM-derived exosomes and conferred the pro-angiogenic effect. Exosomal EPHA2 can be transferred from HM breast cancer cells to endothelial cells. Moreover, it can stimulate the migration and tube-forming abilities of endothelial cells in vitro and promote angiogenesis and tumor metastasis in vivo. Mechanistically, exosomal EPHA2 activates the AMPK signaling via the ligand Ephrin A1-dependent canonical forward signaling pathway. Moreover, inhibition of the AMPK signaling impairs exosomal EPHA2-mediated pro-angiogenic effects. Conclusion: Our findings identify a novel mechanism of exosomal EPHA2-mediated intercellular communication from breast cancer cells to endothelial cells in the tumor microenvironment to provoke angiogenesis and metastasis. Targeting the exosomal EPHA2-AMPK signaling may serve as a potential strategy for breast cancer therapy.

Competition for shared downstream signaling molecules establishes indirect negative feedback between EGFR and EphA2.

Cells sense a variety of extracellular growth factors and signaling molecules through numerous distinct receptor tyrosine kinases (RTKs) on the cell surface. In many cases, the same intracellular signaling molecules interact with more than one type of RTK. How signals from different RTKs retain the identity of the triggering receptor and how (or if) different receptors may synergize or compete remain largely unknown. Here we utilize an experimental strategy, combining microscale patterning and single-molecule imaging, to measure the competition between ephrin-A1:EphA2 and epidermal growth factor (EGF):EGF receptor (EGFR) ligand-receptor complexes for the shared downstream signaling molecules, Grb2 and SOS. The results reveal a distinct hierarchy, in which newly formed EGF:EGFR complexes outcompete ephrin-A1:EphA2 for Grb2 and SOS, revealing a type of negative crosstalk interaction fundamentally controlled by chemical mass action and protein copy number limitations.

An integrated analysis of single-cell and bulk transcriptomics reveals EFNA1 as a novel prognostic biomarker for cervical cancer.

Cervical cancer is a serious threat to women's health and lives worldwide. The recovery and survival of cervical cancer can be improved by customizing therapy strategies based on individual-specific gene expression patterns. EFNA1 was reported to be dysregulated in many cancers and associated with their overall survivals, but its prognostic value in cervical cancer is still unclear. In this study, we performed analyses on the single-cell and bulk RNA sequencing data to study the role of EFNA1 in cervical cancer. EFNA1 was found to be significantly upregulated in cervical cancer tissue, especially the cancer cell subgroup within tumors, which was verified by immunohistochemistry. Through Cox regressions, we found that high EFNA1 expression is an independent risk factor for cervical cancer. Nomogram analysis indicated that EFNA1 could be a predicting factor for the survival probabilities of cervical cancer. Gene ontology and pathway analyses showed that EFNA1 was involved in many tumorigenesis pathways, protein, and virus productions. These findings suggested that EFNA1 could be a prognostic biomarker and potential therapeutic target for cervical cancer.

NuA4 and H2A.Z control environmental responses and autotrophic growth in Arabidopsis.

Nucleosomal acetyltransferase of H4 (NuA4) is an essential transcriptional coactivator in eukaryotes, but remains poorly characterized in plants. Here, we describe Arabidopsis homologs of the NuA4 scaffold proteins Enhancer of Polycomb-Like 1 (AtEPL1) and Esa1-Associated Factor 1 (AtEAF1). Loss of AtEAF1 results in inhibition of growth and chloroplast development. These effects are stronger in the Atepl1 mutant and are further enhanced by loss of Golden2-Like (GLK) transcription factors, suggesting that NuA4 activates nuclear plastid genes alongside GLK. We demonstrate that AtEPL1 is necessary for nucleosomal acetylation of histones H4 and H2A.Z by NuA4 in vitro. These chromatin marks are diminished genome-wide in Atepl1, while another active chromatin mark, H3K9 acetylation (H3K9ac), is locally enhanced. Expression of many chloroplast-related genes depends on NuA4, as they are downregulated with loss of H4ac and H2A.Zac. Finally, we demonstrate that NuA4 promotes H2A.Z deposition and by doing so prevents spurious activation of stress response genes.

May EPH/Ephrin Targeting Revolutionize Lung Cancer Treatment?

Lung cancer (LC) is the leading cause of cancer death in the United States. Erythropoietin-producing hepatocellular receptors (EPHs) comprise the largest receptor tyrosine kinases (RTKs) family in mammals. EPHs along with their ligands, EPH-family receptor-interacting proteins (ephrins), have been found to be either up- or downregulated in LC cells, hence exhibiting a defining role in LC carcinogenesis and tumor progression. In their capacity as membrane-bound molecules, EPHs/ephrins may represent feasible targets in the context of precision cancer treatment. In order to investigate available therapeutics targeting the EPH/ephrin system in LC, a literature review was conducted, using the MEDLINE, LIVIVO, and Google Scholar databases. EPHA2 is the most well-studied EPH/ephrin target in LC treatment. The targeting of EPHA2, EPHA3, EPHA5, EPHA7, EPHB4, EPHB6, ephrin-A1, ephrin-A2, ephrin-B2, and ephrin-B3 in LC cells or xenograft models not only directly correlates with a profound LC suppression but also enriches the effects of well-established therapeutic regimens. However, the sole clinical trial incorporating a NSCLC patient could not describe objective anti-cancer effects after anti-EPHA2 antibody administration. Collectively, EPHs/ephrins seem to represent promising treatment targets in LC. However, large clinical trials still need to be performed, with a view to examining the effects of EPH/ephrin targeting in the clinical setting.

Association of Epidermal Growth Factor 61A>G, Survivin -31G>C, and EFNA1 -1732G>A Polymorphisms with Susceptibility to Colorectal Cancer.

BACKGROUND: Genetic polymorphisms play an important role in the development of colorectal cancer (CRC). Functional variants in the epidermal growth factor (EGF), survivin, and Ephrin A1 (EFNA1) genes have been previously reported to play a potential role in susceptibility to CRC, but these polymorphisms have not been well replicated. The aim of this study was to assess the association of the EGF 61A>G, Survivin -31G>C, and EFNA1 -1732G>A polymorphisms with the susceptibility to CRC in an Iranian population. METHODS: A total of 148 cases diagnosed with CRC and 160 healthy subjects were recruited. The EGF 61A>G, survivin -31G>C, and EFNA1 -1732G>A polymorphisms were genotyped using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. RESULTS: Our data revealed that the homozygous mutant genotype (CC: OR = 2.895, 95% CI = 1.092-7.673, p = 0.033) and mutant allele (C: OR = 1.629, 95% CI = 1.152-2.303, p = 0.006) of the survivin -31G>C were associated with an increased risk of CRC in the Iranian population. However, our results failed to show an association between the EGF 61A>G and EFNA1 -1732G>A polymorphisms and CRC risk. CONCLUSION: Our results revealed that the survivin -31G>C polymorphism might play an important role in development of CRC in Iranian population. However, no association of EGF 61A>G and EFNA1 -1732G>A polymorphisms with CRC risk was found.

Replicating infant-specific reactive astrocyte functions in the injured adult brain.

Infants and adults respond differently to brain injuries. Specifically, improved neuronal sparing along with reduced astrogliosis and glial scarring often observed earlier in life, likely contributes to improved long-term outcomes. Understanding the underlying mechanisms could enable the recapitulation of neuroprotective effects, observed in infants, to benefit adults after brain injuries. We reveal that in primates, Eph/ ephrin signaling contributes to age-dependent reactive astrocyte behavior. Ephrin-A5 expression on astrocytes was more protracted in adults, whereas ephrin-A1 was only expressed on infant astrocytes. Furthermore, ephrin-A5 exacerbated major hallmarks of astrocyte reactivity via EphA2 and EphA4 receptors, which was subsequently alleviated by ephrin-A1. Rather than suppressing reactivity, ephrin-A1 signaling shifted astrocytes towards GAP43+ neuroprotection, accounting for improved neuronal sparing in infants. Reintroducing ephrin-A1 after middle-aged focal ischemic injury significantly attenuated glial scarring, improved neuronal sparing and preserved circuitry. Therefore, beneficial infant mechanisms can be recapitulated in adults to improve outcomes after CNS injuries.

EFNA1 is a potential key gene that correlates with immune infiltration in low-grade glioma.

ABSTRACT: EFNA1 is a key gene that is associated with the pathogenesis of several human cancers. However, the prognostic role of EFNA1 in many cancers and the relationship between EFNA1 and tumor-infiltrating lymphocytes in different cancers remain unclear.The expression levels of EFNA1 in 33 types of cancer in the TCGA (The Cancer Genome Atlas) database were collected via the UCSC Xena browser. The clinical data of LGG (low grade glioma) patients were downloaded from the TCGA database. The glioma data from the CGGA (Chinese Glioma Genome Atlas) database were also downloaded to verify the results. Kaplan-Meier and Cox regression analyses were used to investigate the prognostic value of EFNA1 in different cancers using R software. We verified the differential expression of EFNA1 in glioma and normal brain tissue via gene expression profiling interactive analysis. We evaluated the relationship between the expression level of EFNA1 and the clinicopathological features of LGG patients via the Wilcoxon signed-rank test. The immune infiltration levels were evaluated via tumor immune estimation resource (TIMER) and CIBERSORT, and the correlations between EFNA1 and immune cell levels were investigated via TIMER. Finally, we conducted gene set enrichment analysis (GSEA) to explore the potential mechanisms.Data from the TCGA database showed that EFNA1 was differentially expressed in many kinds of cancers when compared with normal tissues. Upregulated EFNA1 expression in esophageal carcinoma (ESCA), cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC), and LGG correlated with shorter patient overall survival (OS) times. The Cox regression analysis revealed that the expression of EFNA1 was also a risk factor for the disease-specific survival (DSS) and progression-free interval (PFI) of LGG patients. The multiple Cox regression analysis revealed that EFNA1 was an independent prognostic factor for LGG patients. In addition, EFNA1 expression was increased in the WHO grade III group and the 1p19q non-codeletion group. Moreover, EFNA1 expression was positively correlated with the levels of infiltrating CD4+ T cells, myeloid dendritic cells and neutrophils in LGG. GSEA suggested that several GO and kyoto encyclopedia of genes and genomes (KEGG) items associated with nervous system function and apoptotic pathway were significantly enriched in the EFNA1-low and EFNA1-high expression phenotypes.EFNA1 may play a pivotal role in the development of LGG and may serve as a potential marker for LGG prognosis and therapy.

Drug-resistant cancer cell-derived exosomal EphA2 promotes breast cancer metastasis via the EphA2-Ephrin A1 reverse signaling.

Tumor metastasis induced by drug resistance is a major challenge in successful cancer treatment. Nevertheless, the mechanisms underlying the pro-invasive and metastatic ability of drug resistance remain elusive. Exosome-mediated intercellular communications between cancer cells and stromal cells in tumor microenvironment are required for cancer initiation and progression. Recent reports have shown that communications between cancer cells also promote tumor aggression. However, little attention has been regarded on this aspect. Herein, we demonstrated that drug-resistant cell-derived exosomes promoted the invasion of sensitive breast cancer cells. Quantitative proteomic analysis showed that EphA2 was rich in exosomes from drug-resistant cells. Exosomal EphA2 conferred the invasive/metastatic phenotype transfer from drug-resistant cells to sensitive cells. Moreover, exosomal EphA2 activated ERK1/2 signaling through the ligand Ephrin A1-dependent reverse pathway rather than the forward pathway, thereby promoting breast cancer progression. Our findings indicate the key functional role of exosomal EphA2 in the transmission of aggressive phenotype between cancer cells that do not rely on direct cell-cell contact. Our study also suggests that the increase of EphA2 in drug-resistant cell-derived exosomes may be an important mechanism of chemotherapy/drug resistance-induced breast cancer progression.

Analysis of ADAM12-Mediated Ephrin-A1 Cleavage and Its Biological Functions.

Accumulating evidence indicates that an elevated ephrin-A1 expression is positively correlated with a worse prognosis in some cancers such as colon and liver cancer. The detailed mechanism of an elevated ephrin-A1 expression in a worse prognosis still remains to be fully elucidated. We previously reported that ADAM12-cleaved ephrin-A1 enhanced lung vascular permeability and thereby induced lung metastasis. However, it is still unclear whether or not cleaved forms of ephrin-A1 are derived from primary tumors and have biological activities. We identified the ADAM12-mediated cleavage site of ephrin-A1 by a Matrix-assisted laser desorption ionization mass spectrometry and checked levels of ephrin-A1 in the serum and the urine derived from the primary tumors by using a mouse model. We found elevated levels of tumor-derived ephrin-A1 in the serum and the urine in the tumor-bearing mice. Moreover, inhibition of ADAM-mediated cleavage of ephrin-A1 or antagonization of the EphA receptors resulted in a significant reduction of lung metastasis. The results suggest that tumor-derived ephrin-A1 is not only a potential biomarker to predict lung metastasis from the primary tumor highly expressing ephrin-A1 but also a therapeutic target of lung metastasis.

The Expression of ephrinA1/ephA2 Receptor Increases in Chronic Rhinosinusitis and ephrinA1/ephA2 Signaling Affects Rhinovirus-Induced Innate Immunity in Human Sinonasal Epithelial Cells.

EphA2 receptor and its ephrin ligands are involved in virus infection, epithelial permeability, and chemokine secretion. We hypothesized that ephrinA1/ephA2 signaling participates in rhinovirus (RV)-induced antiviral immune response in sinonasal mucosa of patients with chronic rhinosinusitis (CRS). Therefore, we investigated the expression of ephrinA1/ephA2 in normal and inflamed sinonasal mucosa and evaluated whether they regulate chemokine secretion and the production of antiviral immune mediators including interferons (IFNs) in RV-infected human primary sinonasal epithelial cells. For this purpose, the expression and distribution of ephrinA1/ephA2 in sinonasal mucosa were evaluated with RT-qPCR, immunofluorescence, and western blot. Their roles in chemokine secretion and the production of antiviral immune mediators such as type I and III IFNs, and interferon stimulated genes were evaluated by stimulating ephA2 with ephrinA1 and inactivating ephA2 with ephA2 siRNA or inhibitor in cells exposed to RV and poly(I:C). We found that ephrinA1/ephA2 were expressed in normal mucosa and their levels increased in inflamed sinonasal mucosa of CRS patients. RV infection or poly(I:C) treatment induced chemokine secretion which were attenuated by blocking the action of ephA2 with ephA2 siRNA or inhibitor. The production of antiviral immune mediators enhanced by rhinovirus or poly (I:C) is increased by blocking ephA2 compared with that of cells stimulated by either rhinovirus or poly(I:C) alone. In addition, blocking ephA2 attenuated RV replication in cultured cells. Taken together, these results describe a novel role of ephrinA1/ephA2 signaling in antiviral innate immune response in sinonasal epithelium, suggesting their participation in RV-induced development and exacerbations of CRS.