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Background and Aims: Tumor growth and progression are affected by interactions between tumor cells and stromal cells within the tumor microenvironment. We previously showed that the expression of an integral membrane protein, called stomatin, was increased in cancer cells following their association with stromal cells. Additionally, stomatin impaired the Akt signaling pathway to suppress tumor growth. However, it remains unclear how stomatin expression is regulated. To explore this, we examined the cell surface molecules that can transduce the intercellular communication signals between cancer cells and stromal cells., Results: Among these molecules, EphA3 and EphA7 receptors and their ligand ephrin-A5 were found to be expressed in prostate cancer cells, but not in prostate stromal cells. Cell-to-cell contact of prostate cancer cells through the EphA-ephrin-A interaction suppressed stomatin expression, while knockdown of EphA3/7 or ephrin-A5 increased stomatin expression. This increase contributed to an inhibition of prostate cancer cell proliferation. Intracellularly, the binding of ephrin-A to EphA attenuated extracellular signaling-regulated kinase (ERK) activation that promoted stomatin expression. Furthermore, ELK1 and ELK4, which are Ets family transcription factors phosphorylated by ERK, were involved in the induction of stomatin expression. We also found that higher Gleason score prostate cancer tissue samples had increased activation of EphA, while the stomatin expression and activated ERK and ELK levels were all low. In the mouse xenograft tumor samples generated by implantation of prostate cancer cells, EphA3 phosphorylation was attenuated and the ERK-ELK signaling and stomatin expression were enhanced in the area where stromal cells infiltrated the tumor., Conclusion: The EphA-mediated signaling suppresses the ERK-ELK pathway, leading to the reduction of stomatin expression that affects prostate cancer malignancy., (© 2024 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)

Ephrin receptor A7 (EphA7) is a member of the Eph receptor family. It is widely involved in signal transduction between cells, regulates cell proliferation and differentiation, and participates in developing neural tubes and brain. In addition, EphA7 also has a dual role of tumor promoter and tumor suppressor. It can participate in cell proliferation, migration and apoptosis through various mechanisms, and affect tumor differentiation, staging and prognosis. EphA7 may be a potential diagnostic marker and tumor treatment target. This article reviews the effects of EphA7 on a variety of tumor biological processes and pathological characteristics, as well as specific effects and regulatory mechanisms., (© 2022. The Author(s), under exclusive licence to Federación de Sociedades Españolas de Oncología (FESEO).)

Background: Aberrant methylation of EphA7 has been reported in the process of carcinogenesis but not in cervical cancer. Therefore, an integration study was performed to explore the association between EphA7 hypermethylation and cervical cancer and validate the potential value of EphA7 hypermethylation in the diagnosis of cervical cancer., Methods: We performed an integration study to identify and validate the association between EphA7 methylation and cervical cancer. First, data on EphA7 methylation and expression in cervical cancer were extracted and analyzed via bioinformatics tools. Subsequently, CRISPR-based methylation perturbation tools (dCas9-Tet1/DNMT3a) were constructed to further demonstrate the association between DNA methylation and EphA7 expression. Ultimately, the clinical value of EphA7 methylation in cervical cancer was validated in cervical tissues and Thinprep cytologic test (TCT) samples by methylation-specific PCR (MSP) and quantitative methylation-specific PCR (QMSP), respectively., Results: Pooled analysis showed that EphA7 promoter methylation levels were significantly increased in cervical cancer compared to normal tissues (P < 0.001) and negatively correlated with EphA7 expression. These prediction results were subsequently confirmed in cell lines; moreover, CRISPR-based methylation perturbation tools (dCas9-Tet1/DNMT3a) demonstrated that DNA methylation participates in the regulation of EphA7 expression directly. Consistent with these findings, the methylation level and the positive rate of EphA7 gradually increased with severity from normal to cancer stages in TCT samples (P < 0.01)., Conclusions: EphA7 hypermethylation is present in cervical cancer and is a potential biomarker for the diagnosis of cervical cancer., (© 2022. The Author(s).)

Basal cell carcinoma (BCC) is the most common malignancy worldwide, with increasing incidence. BCCs present low mortality but high morbidity, and its pathogenesis remains unclear. Eph receptors have been implicated in tumorigenesis. EphA7 plays a role as a tumor suppressor in certain cancers. We checked EphA7 expression levels and methylation status in a set of BCCs, benign skin diseases, and compound nevus tissue samples using immunohistochemistry. EphA7 protein was positively expressed in normal basal cells, benign skin diseases, and compound nevus cells, but lost in areas of BCC tissues. We detected hypermethylation in BCC tissue samples with reduced expression of EphA7. There is a significant relationship between the expression level of EphA7 receptor protein and the methylation status of CpG islands in the EphA7 promoter region ( P < 0.001). To our knowledge, this is the first study to report the EphA7 expression profile and hypermethylation of EphA7 in BCC. The role of the EphA7 gene and the status of hypermethylation in tumorigenesis and treatment of BCC warrant further investigation., Competing Interests: The authors declare that no conflict of interest exists., (Copyright © 2022 Jie Liu et al.)

Background: Triple-negative breast cancer (TNBC) represents about 19% of all breast cancer cases in the Chinese population. Lack of targeted therapy contributes to the poorer outcomes compared with other breast cancer subtypes. Comprehensive genomic profiling helps to explore the clinically relevant genomic alterations (CRGAs) and potential therapeutic targets in very-early-relapsed TNBC patients., Methods: Formalin-fixed paraffin-embedded (FFPE) tumour tissue specimens from 23 patients with very-early-relapsed TNBC and 13 patients with disease-free survival (DFS) more than 36 months were tested by FoundationOne CDx (F1CDx) in 324 genes and select gene rearrangements, along with genomic signatures including microsatellite instability (MSI) and tumour mutational burden (TMB)., Results: In total, 137 CRGAs were detected in the 23 very-early-relapsed TNBC patients, averaging six alterations per sample. The mean TMB was 4 Muts/Mb, which was higher than that in non-recurrence patients, and is statistically significant. The top-ranked altered genes were TP53 (83%), PTEN (35%), RB1 (30%), PIK3CA (26%) and BRCA1 (22%). RB1 mutation carriers had shorter DFS. Notably, 100% of these patients had at least one CRGA, and 87% of patients had at least one actionable alteration. In pathway analysis, patients who carried a mutation in the cell cycle pathway were more likely to experience very early recurrence. Strikingly, we detected one patient with ERBB2 amplification and one patient with ERBB2 exon20 insertion, both of which were missed by immunohistochemistry (IHC). We also detected novel alterations of ROS1-EPHA7 fusion for the first time, which has not been reported in breast cancer before., Conclusions: The comprehensive genomic profiling can identify novel treatment targets and address the limited options in TNBC patients. Therefore, incorporating F1CDx into TNBC may shed light on novel therapeutic opportunities for these very-early-relapsed TNBC patients.

Ephrin receptor and their ligands, the ephrins, are widely expressed in the developing brain. They are implicated in several developmental processes that are crucial for brain development. Deletions in genes encoding for members of the Eph/ephrin receptor family were reported in several neurodevelopmental disorders. The ephrin receptor A7 gene (EPHA7) encodes a member of ephrin receptor subfamily of the protein-tyrosine kinase family. EPHA7 plays a role in corticogenesis processes, determines brain size and shape, and is involved in development of the central nervous system. One patient only was reported so far with a de novo deletion encompassing EPHA7 in 6q16.1. We report 12 additional patients from nine unrelated pedigrees with similar deletions. The deletions were inherited in nine out of 12 patients, suggesting variable expressivity and incomplete penetrance. Four patients had tiny deletions involving only EPHA7, suggesting a critical role of EPHA7 in a neurodevelopmental disability phenotype. We provide further evidence for EPHA7 deletion as a risk factor for neurodevelopmental disorder and delineate its clinical phenotype., (© 2021 John Wiley & Sons A/S . Published by John Wiley & Sons Ltd.)

Erythropoietin producing hepatocellular (Eph) forms the largest family of receptor tyrosine kinases (RTK). As a family, Eph regulates physiological events such as cell-cell interaction, cell migration, and adhesion. The Kinase domain is the catalytic core of the Eph receptor and is highly conserved sequentially. EphA7 has been recently regarded as a cancer driver gene and comprises several clinically important mutations. Three of the EphA7 mutations Gly656Glu, Gly656Arg, and Asp751His, present in the kinase domain, are predicted to be highly pathogenic. Furthermore, Gly656Glu and Gly656Arg are reported to be hotspot mutations. Considering the importance of mutations, crystals structure of EphA7 Gly656Glu, Gly656Arg, and Asp751His mutants has been explored. Changes in folding pattern and intramolecular interactions were observed in mutant structures. Secondary structural changes were observed in the hinge region of EphA7 Gly656Arg and Asp751His structure, affecting the transition of kinase domain between open and closed conformations. EphA7 Asp751His mutant structure shows a distorted nucleotide-binding groove. Differences were observed in hydrogen bonding and hydrophobic interactions between the catalytic and highly conserved DFG motif in the EphA7 mutants, which may influence the catalytic activity of kinase domain., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Micro (mi)RNAs serve crucial roles in cancer development although little is known about their cellular mechanisms in the pathogenesis of melanoma. The present study explored the regulatory roles of miR‑18a‑5p in melanoma cell proliferation, apoptosis and autophagy, in addition to its target gene in melanoma cells. miRNA and ephrin receptor A7 (EPHA7) mRNA were analyzed by reverse transcription‑quantitative PCR. Cell Counting Kit‑8 and colony formation assays were performed to examine the cell proliferation rate. Hoechst staining and flow cytometry were performed to investigate cell apoptosis. Western blotting was used to estimate the abundance of proteins. Dual-luciferase reporter assay verified the binding of miRNA with target gene sequences. Melanoma tissues and cell lines exhibited markedly elevated miR‑18a‑5p expression. miR‑18a‑5p inhibitor inhibited proliferation rates, and triggered apoptosis and autophagy marker protein expression in WM266‑4 and A375 cells. It also negatively regulated EPHA7 expression in WM266‑4 and A375 cells by directly binding at the 3'‑untranslated region of EPHA7. miR‑18a‑5p mimics reversed the EPHA7 overexpression‑induced suppression of proliferation, and the EPHA7 overexpression‑induced promotion of apoptosis and autophagy. miR‑18a‑5p triggered proliferation of melanoma cells and inhibited apoptosis and autophagy by directly targeting and inhibiting EPHA7 expression. Thus, the present study aided our understanding of miRNA‑mediated melanoma pathogenesis.

We have previously shown that systemic injection of erythropoietin-producing hepatocellular receptor A7 (EPHA7)-Fc raises serum luteinizing hormone (LH) levels before ovulation in female rats, indicating the induction of EPHA7 in ovulation. In this study, we aimed to identify the mechanism and hypothalamus-pituitary-ovary (HPO) axis level underlying the promotion of LH secretion by EPHA7. Using an ovariectomized (OVX) rat model, in conjunction with low-dose 17β-estradiol (E 2 ) treatment, we investigated the association between EPHA7-ephrin (EFN)A5 signaling and E 2 negative feedback. Various rat models (OVX, E 2 -treated OVX, and abarelix treated) were injected with the recombinant EPHA7-Fc protein through the caudal vein to investigate the molecular mechanism underlying the promotion of LH secretion by EPHA7. Efna5 was observed strongly expressed in the arcuate nucleus of the female rat by using RNAscope in situ hybridization. Our results indicated that E 2 , combined with estrogen receptor (ER)α, but not ERβ, inhibited Efna5 and gonadotropin-releasing hormone 1 ( Gnrh1) expressions in the hypothalamus. In addition, the systemic administration of EPHA7-Fc restrained the inhibition of Efna5 and Gnrh1 by E 2 , resulting in increased Efna5 and Gnrh1 expressions in the hypothalamus as well as increased serum LH levels. Collectively, our findings demonstrated the involvement of EPHA7-EFNA5 signaling in the regulation of LH and the E 2 negative feedback pathway in the hypothalamus, highlighting the functional role of EPHA7 in female reproduction.

Objective: Non-small cell lung cancer (NSCLC) is a primary subtype of lung cancers which has a high morbidity and poor prognosis. Emerging evidence has demonstrated that aberrantly expressed microRNAs (miRNAs) were implicated in the regulatory functions of multiple processes during tumorigenesis. In the current study, we explored the functional roles and underlying mechanisms of miR-448 in NSCLC., Patients and Methods: Quantitative real-time polymerase chain reaction assays were conducted to measure miR-448 expressions in 51 pairs of NSCLC tissues and corresponding normal tissues. Moreover, the relationship between miR-448 expressions and clinicopathological characteristics of NSCLC patients was also determined. We then performed transwell assays to explore the functions of miR-448 in NSCLC cell invasion and migration. As we had identified EPHA7 as a functional target of miR-448 in NSCLC cells, the clinical significance of EPHA7 in NSCLC patients was further investigated. Finally, we detected the influence of miR-448 on tumor growth rate and tumor size of NSCLC using tumor xenografts., Results: Underexpressed miR-448 was identified in NSCLC, and low miR-448 expression was confirmed to be associated with the poor prognosis and adverse clinicopathologic features of NSCLC patients. Moreover, functional assays demonstrated that miR-448 overexpression suppressed NSCLC cell proliferation, invasion and migration. EPHA7 was identified as a direct target of miR-448. Additionally, miR-448 restoration suppressed in vivo NSCLC cell growth. Finally, our studies also indicated that miR-448 exerted anti-NSCLC functions via regulating PI3K/AKT signaling pathway and EMT., Conclusions: These results showed that miR-448/EPHA7 axis maybe one of the useful diagnostic and prognostic biomarkers for NSCLC patients.

Receptor tyrosine kinase EphA7 is specifically expressed in otic region in Xenopus early development. However, its role in otocyst development remains unknown. Knockdown of EphA7 by a specific morpholino oligonucleotide (MO) reduced the size of the otocyst and triggered otic epithelial cell extrusion. Interestingly, EphA7 depletion attenuated the membrane level of the tight junction protein Claudin6 (CLDN6). Utilizing the Cldn6 MO, we further confirmed that CLDN6 attenuation also led to otic epithelial cell extrusion. Our work suggested that EphA7 modulates the otic epithelial homeostasis through stabilizing the CLDN6 membrane level., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi's sarcoma and is associated with two B cell malignancies, primary effusion lymphoma (PEL) and the plasmablastic variant of multicentric Castleman's disease. On several adherent cell types, EphA2 functions as a cellular receptor for the gH/gL glycoprotein complex of KSHV. KSHV gH/gL also has previously been found to interact weakly with other members of the Eph family of receptor tyrosine kinases (Ephs), and other A-type Ephs have been shown to be able to compensate for the absence of EphA2 using overexpression systems. However, whether these interactions are of functional consequence at endogenous protein levels has remained unclear so far. Here, we demonstrate for the first time that endogenously expressed EphA7 in BJAB B cells is critical for the cell-to-cell transmission of KSHV from producer iSLK cells to BJAB target cells. The BJAB lymphoblastoid cell line often serves as a model for B cell infection and expresses only low levels of all Eph family receptors other than EphA7. Endogenous EphA7 could be precipitated from the cellular lysate of BJAB cells using recombinant gH/gL, and knockout of EphA7 significantly reduced transmission of KSHV into BJAB target cells. Knockout of EphA5, the second most expressed A-type Eph in BJAB cells, had a similar, although less pronounced, effect on KSHV infection. Receptor function of EphA7 was conserved for cell-free infection by the related rhesus monkey rhadinovirus (RRV), which is relatively even more dependent on EphA7 for infection of BJAB cells. IMPORTANCE Infection of B cells is relevant for two KSHV-associated malignancies, the plasmablastic variant of multicentric Castleman's disease and PEL. Therefore, elucidating the process of B cell infection is important for the understanding of KSHV pathogenesis. While the high-affinity receptor for the gH/gL glycoprotein complex, EphA2, has been shown to function as an entry receptor for various types of adherent cells, the gH/gL complex can also interact with other Eph receptor tyrosine kinases with lower avidity. We analyzed the Eph interactions required for infection of BJAB cells, a model for B cell infection by KSHV. We identified EphA7 as the principal Eph receptor for infection of BJAB cells by KSHV and the related rhesus monkey rhadinovirus. While two analyzed PEL cell lines exhibited high EphA2 and low EphA7 expression, a third PEL cell line, BCBL-1, showed high EphA7 and low EphA2 expression, indicating a possible relevance for KSHV pathology., (Copyright © 2019 American Society for Microbiology.)

Tumour sequencing identifies highly recurrent point mutations in cancer driver genes, but rare functional mutations are hard to distinguish from large numbers of passengers. We developed a novel computational platform applying a multi-modal approach to filter out passengers and more robustly identify putative driver genes. The primary filter identifies enrichment of cancer mutations in CATH functional families (CATH-FunFams) - structurally and functionally coherent sets of evolutionary related domains. Using structural representatives from CATH-FunFams, we subsequently seek enrichment of mutations in 3D and show that these mutation clusters have a very significant tendency to lie close to known functional sites or conserved sites predicted using CATH-FunFams. Our third filter identifies enrichment of putative driver genes in functionally coherent protein network modules confirmed by literature analysis to be cancer associated. Our approach is complementary to other domain enrichment approaches exploiting Pfam families, but benefits from more functionally coherent groupings of domains. Using a set of mutations from 22 cancers we detect 151 putative cancer drivers, of which 79 are not listed in cancer resources and include recently validated cancer associated genes EPHA7, DCC netrin-1 receptor and zinc-finger protein ZNF479.

Background: The ovulatory dysfunction mechanisms underlying polycystic ovary syndrome (PCOS) are not completely understood. And the roles of EPHA7 and EPHA7-regulated pathway factors in the pathogenesis of anovulation remain to be elucidated., Methods: We used human granulosa cells (hGCs) of PCOS and non-PCOS patients to measure EPHA7 and other target gene expressions. We performed in vitro experiments in KGN cells to verify the molecular mechanisms. Additionally, we conducted in vivo loss- and gain-of-function studies using EPHA7 shRNA lentivirus and recombinant EPHA7-Fc protein injection to identify the ovulation effects of EPHA7., Findings: EPHA7 functions as a critically positive upstream factor for the expression of ERK1/2-mediated C/EBPβ. This protein, in turn, induced the expression of KLF4 and then ADAMTS1. Moreover, decreased abundance of EPHA7 was positively correlated with that of its downstream factors in hGCs of PCOS patients. Additionally, a 1-week functional EPHA7 shRNA lentivirus in rat ovaries contributed to decreased numbers of retrieved oocytes, and a 3-week functional lentivirus led to menstrual disorders and morphological polycystic changes in rat ovaries. More importantly, we found that EPHA7 triggered ovulation in rats, and it improved polycystic ovarian changes induced by DHEA in PCOS rats., Interpretation: Our findings demonstrate a new role of EPHA7 in PCOS, suggesting that EPHA7 is an effective target for the development of innovative medicines to induce ovulation. FUND: National Key Research and Development Program of China, National Natural Science Foundation, Shanghai Municipal Education Commission--Gaofeng Clinical Medicine, and Shanghai Commission of Science and Technology., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Eph/ephrin molecules are widely expressed during embryonic development, and function in a variety of developmental processes. Here we studied the roles of the Eph receptor EphA7 and its soluble form in Xenopus pronephros development. EphA7 is specifically expressed in pronephric tubules at tadpole stages and knockdown of EphA7 by a translation blocking morpholino led to defects in tubule cell differentiation and morphogenesis. A soluble form of EphA7 (sEphA7) was also identified. Interestingly, the membrane level of claudin6 (CLDN6), a tetraspan transmembrane tight junction protein, was dramatically reduced in the translation blocking morpholino injected embryos, but not when a splicing morpholino was used, which blocks only the full length EphA7. In cultured cells, EphA7 binds and phosphorylates CLDN6, and reduces its distribution at the cell surface. Our work suggests a role of EphA7 in the regulation of cell adhesion during pronephros development, whereas sEphA7 works as an antagonist., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The downregulation of receptor tyrosine kinase EphA7 is frequent in epithelial cancers and linked to tumor progression. However, the detailed mechanism of EphA7-mediated prostate tumor progression remains elusive. To test the role of EphA7 receptor in prostate cancer (PCa) progression directly, we generated EphA7 receptor variants that were either lacking the cytoplasmic domain or carrying a point mutation that inhibits its phosphorylation by site-directed mutagenesis. Overexpression of wild-type (WT) EphA7 in PCa cells resulted in decreased tumor volume and increased tumor apoptosis in primary tumors. In addition, ectopic expression of WT EphA7 both can delay PCa cell proliferation and could inhibit PCa cell migration and invasion. This protein can also induce PCa cell apoptosis that correlated with increasing the protein expression levels of Bax, elevating the caspase-3 activities, reducing the protein expression levels of Bcl-2 and facilitating the dephosphorylation of Akt, which is further increased by the stimulation of ephrinA5-Fc. However, expression of these EphA7 mutants in PCa cells has no effect in vivo and in vitro. The expression of EphA7 and ephrinA5 was significantly decreased in PCa specimens compared with BPH tissues or paired normal tissues. Moreover, the phosphorylation of EphA7 was positively related with ephrinA5 expression in human prostate tissues. In sum, receptor phosphorylation of EphA7, at least in part, suppress PCa tumor malignancy through targeting PI3K/Akt signaling pathways.

Human induced pluripotent stem-cell-derived cardiomyocytes (hiPSC CMs) may be used in regenerative medicine for individualized tissue transplants in the future. For application in patients, the generated CMs have to be highly pure and well characterized. In order to overcome the prevalent scarcity of CM-specific markers, we quantitatively assessed cell-surface-exposed sialo-glycoproteins and N-glycans of hiPSCs, CM progenitors, and CMs. Applying a combination of metabolic labeling and specific sialo-glycoprotein capture, we could highly enrich and quantify membrane proteins during cardiomyogenic differentiation. Among them we identified a number of novel, putative biomarkers for hiPSC CMs. Analysis of the N-glycome by capillary gel electrophoresis revealed three novel structures comprising β1,3-linked galactose, α2,6-linked sialic acid and complex fucosylation; these were highly specific for hiPSCs. Bisecting GlcNAc structures strongly increased during differentiation, and we propose that they are characteristic of early, immature CMs., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Osteosarcoma is the most common type of malignant bone tumor, often affecting adolescents and children. MicroRNAs (miRNAs) are a group of small, non-protein coding, endogenous RNAs that play critical roles in osteosarcoma tumorigenesis. In our study, we demonstrated that miR-448 expression was downregulated in osteosarcoma tissues and cell lines. Overexpression of miR-448 suppressed osteosarcoma cell proliferation, colony formation and migration. Moreover, we found that EPHA7 was a direct target gene of miR-448 in osteosarcoma cells. We further demonstrated that the EPHA7 expression level was upregulated in osteosarcoma tissues. Interestingly, the expression level of EPHA7 was inversely correlated with the expression level of miR-448 in osteosarcoma tissues. In addition, elevated expression of miR-448 suppressed osteosarcoma cell proliferation and invasion through targeting EPHA7. Taken together, these findings suggest that miR-448 functioned as a tumor suppressor gene in the development of osteosarcoma through targeting EPHA7.

The proliferation, differentiation, adhesion, and migration of hematopoietic stem and progenitor cells (HSPCs) are dependent upon bone marrow stromal cells (BMSCs). In this study, we found that human primitive HSPCs (CD34 + CD38 - ), but not lineage-committed hematopoietic cell populations, express the tyrosine kinase receptors EphA5 and EphA7. Moreover, we found that the ephrinA5 ligand, the high-affinity binding partner of EphA5 and EphA7, is highly expressed by primary human BMSCs. Previous studies have reported that interactions between EphA and ephrinA play important roles in hematopoietic cell trafficking; however, their role in BMSC support of hematopoiesis had not been described previously. Herein, we show that stimulating EphA5 and/or EphA7 forward signaling in HSPCs using soluble ephrinA5-Fc molecules promoted human HSPC-derived colony formation significantly and was associated with increased expression of granulocyte macrophage colony-stimulating factor receptor on HSPCs. Studies using functional blocking peptides to EphA5/7 found that disruption of EphA5/ephrinA5 and/or EphA7/ephrinA5 interactions inhibited HSPC function in BMSC-dependent long-term culture-initiating cell assays. Furthermore, the adhesion and migration of HSPCs was increased significantly in the presence of ephrinA5-Fc molecules compared with human immunoglobulin G-treated controls. Conversely, blocking EphA5 activation led to a reduction of HSPC adhesion, whereas inhibiting EphA5 and/or EphA7 activation hindered HSPC migration. Analysis of HSPC cultured in the presence of ephrinA5-Fc showed that EphA forward signaling stimulated Rac1 gene and protein expression and the Rac1 target molecule WAVE1. Moreover, a significant reduction of ephrinA5-mediated HSPC adhesion and migration was observed in the presence of Rac1 inhibitor. These findings suggest that interactions between EphA and ephrinA5 are important in maintaining the HSPC niche mediated in part by activation of Rac1 signaling., (Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.)

Eph receptor tyrosine kinases (RTKs) and their ephrin ligands play multiple roles in the developing nervous system, including cell segregation, axon guidance and synaptic plasticity. Here we report the expression and function of EphA7 in Xenopus hindbrain development. EphA7 is specifically expressed in the hindbrain throughout neurulation in Xenopus embryos. Knockdown of EphA7 by specific morpholino oligonucleotide (MO) disrupted cranial neural tube closure and disturbed apical constriction of hindbrain neuroepithelial cells, indicating weakened cell surface tension. In neural plate explants, EphA7 knockdown inhibited apical filamentous actin (F-actin) accumulation. We further showed that EphA7 is involved in the phosphorylation and activation of focal adhesion kinase (FAK) in vivo and in vitro, a key regulator of actin assembly. Our findings reveal that EphA7 functions as a critical regulator of apical constriction of hindbrain neuroepithelial cells., (Copyright © 2016. Published by Elsevier Inc.)

Bmi1 was originally identified as a gene that contributes to the development of mouse lymphoma by inhibiting MYC-induced apoptosis through repression of Ink4a and Arf. It codes for the Polycomb group protein BMI-1 and acts primarily as a transcriptional repressor via chromatin modifications. Although it binds to a large number of genomic regions, the direct BMI-1 target genes described so far do not explain the full spectrum of BMI-1-mediated effects. Here we identify the putative tumor suppressor gene EphA7 as a novel direct BMI-1 target in neural cells and lymphocytes. EphA7 silencing has been reported in several different human tumor types including lymphomas, and our data suggest BMI1 overexpression as a novel mechanism leading to EphA7 inactivation via H3K27 trimethylation and DNA methylation., Competing Interests: The authors declare no conflicts of interest.

Neuronal transmission is regulated by the local circuitry which is composed of principal neurons targeted at different subcellular compartments by a variety of interneurons. However, mechanisms that contribute to the subcellular localisation and maintenance of GABAergic interneuron terminals are poorly understood. Stabilization of GABAergic synapses depends on clustering of the postsynaptic scaffolding protein gephyrin and its interaction with the guanine nucleotide exchange factor collybistin. Lentiviral knockdown experiments in adult rats indicated that the receptor tyrosine kinase EphA7 is required for the stabilisation of basket cell terminals on proximal dendritic and somatic compartments of granular cells of the dentate gyrus. EphA7 deficiency and concomitant destabilisation of GABAergic synapses correlated with impaired long-term potentiation and reduced hippocampal learning. Reduced GABAergic innervation may be explained by an impact of EphA7 on gephyrin clustering. Overexpression or ephrin stimulation of EphA7 induced gephyrin clustering dependent on the mechanistic target of rapamycin (mTOR) which is an interaction partner of gephyrin. Gephyrin interactions with mTOR become released after mTOR activation while enhanced interaction with the guanine nucleotide exchange factor collybistin was observed in parallel. In conclusion, EphA7 regulates gephyrin clustering and the maintenance of inhibitory synaptic connectivity via mTOR signalling.

Deciphering the molecular basis for guiding specific aspects of neocortical development remains a challenge because of the complexity of histogenic events and the vast array of protein interactions mediating these events. The Eph family of receptor tyrosine kinases is implicated in a number of neurodevelopmental activities. Eph receptors have been known to be capable of responding to several ephrin ligands within their subgroups, often eliciting similar downstream effects. However, several recent studies have indicated specificity between receptor-ligand pairs within each subfamily, the functional relevance of which is not defined. Here we show that a receptor of the EphA subfamily, EphA4, has effects distinct from those of its close relative, EphA7, in the developing brain. Both EphA4 and EphA7 interact similarly with corresponding ligands expressed in the developing neocortex. However, only EphA7 shows strong interaction with ligands in the somatosensory thalamic nuclei; EphA4 affects only cortical neuronal migration, with no visible effects on the guidance of corticothalamic (CT) axons, whereas EphA7 affects both cortical neuronal migration and CT axon guidance. Our data provide new evidence that Eph receptors in the same subfamily are not simply interchangeable but are functionally specified through selective interactions with distinct ligands in vivo. J. Comp. Neurol. 524:2080-2092, 2016. © 2015 Wiley Periodicals, Inc., (© 2015 Wiley Periodicals, Inc.)

During the development of periphery auditory circuitry, spiral ganglion neurons (SGNs) form a spatially precise pattern of innervation of cochlear hair cells (HCs), which is an essential structural foundation for central auditory processing. However, molecular mechanisms underlying the developmental formation of this precise innervation pattern remain not well understood. Here, we specifically examined the involvement of Eph family members in cochlear development. By performing RNA-sequencing for different types of cochlear cell, in situ hybridization, and immunohistochemistry, we found that EphA7 was strongly expressed in a large subset of SGNs. In EphA7 deletion mice, there was a reduction in the number of inner radial bundles originating from SGNs and projecting to HCs as well as in the number of ribbon synapses on inner hair cells (IHCs), as compared with wild-type or heterozygous mutant mice, attributable to fewer type I afferent fibers. The overall activity of the auditory nerve in EphA7 deletion mice was also reduced, although there was no significant change in the hearing intensity threshold. In vitro analysis further suggested that the reduced innervation of HCs by SGNs could be attributed to a role of EphA7 in regulating outgrowth of SGN neurites as knocking down EphA7 in SGNs resulted in diminished SGN fibers. In addition, suppressing the activity of ERK1/2, a potential downstream target of EphA7 signaling, either with specific inhibitors in cultured explants or by knocking out Prkg1, also resulted in reduced SGN fibers. Together, our results suggest that EphA7 plays an important role in the developmental formation of cochlear innervation pattern through controlling SGN fiber ontogeny. Such regulation may contribute to the salience level of auditory signals presented to the central auditory system., (© 2015 Wiley Periodicals, Inc.)

Previous studies have demonstrated that ephrin (Eph) family receptor tyrosine kinases and ligands promote cancer growth, invasion and metastasis. In addition, it has been reported that Eph receptor A7 (EphA7) is transcriptionally activated in lung cancer; however, the effects of silencing EphA7 expression on the growth of lung cancer cells, and the underlying molecular mechanisms, have yet to be determined. Therefore, the present study aimed to investigate whether silencing EphA7 with small interfering (si)RNA could induce apoptosis in non‑small cell lung cancer (NSCLC) cells. Furthermore, the effects of siEphA7 on cell migration and invasion were evaluated using Transwell assays. The mechanisms underlying the effects of siEphA7 on the tumorigenic properties of A549 cells were also examined. The results of the present study demonstrated that transfection with siEphA7 inhibited the proliferation, migration and invasion of A549 cells. In addition, siEphA7 significantly increased the protein expression levels of B‑cell lymphoma 2 (Bcl‑2)‑associated X protein and caspase‑3, and decreased the protein expression levels of Bcl‑2, thus suggesting that siEphA7 was able to induce apoptosis via the intrinsic apoptotic pathway. In addition, the expression levels of phosphatase and tensin homolog (PTEN) were significantly upregulated, and the expression levels of total AKT were not altered, whereas the levels of phosphorylated‑AKT were reduced. These findings indicated that EphA7 may have an important role in the pathogenesis of NSCLC by regulating PTEN expression via the PTEN/AKT pathway. Silencing EphA7 may provide a novel approach for the treatment of NSCLC.

EphA7 is a key molecule in regulating the development of the dien- and mesencephalon. To get insight into the mechanism of how EphA7 gene expression is regulated during the dorsal specification of the dien- and mesencephalon, we investigated the cis-acting regulatory sequence driving EphA7 to the dorsal midline of the dien- and mesencephalon. Transgenic LacZ reporter analysis, using overlapping EphA7 BACs, was used to narrow down the dorsal midline-specific enhancer, revealing the 25.3 kb genomic region as the enhancer candidate. Strikingly, this genomic DNA was located far downstream of the EphA7 transcription start site, +302.6 kb to +327.9 kb. Further enhancer mapping, using comparative genomic analysis and transgenic methods, showed that the 187 bp genomic DNA alone, approximately 305 kb downstream of the EphA7 transcription start site, was sufficient to act as the dorsal midline-specific enhancer of EphA7. Importantly, our results indicate that the 187 bp dorsal midline-specific enhancer is critically regulated by homeobox transcription factors during the development of the dien- and mesencephalon.

The role of secreted molecules in cellular reprogramming has been poorly understood. Here we identify a truncated form of ephrin receptor A7 (EPHA7) as a key regulator of reprogramming. Truncated EPHA7 is prominently upregulated and secreted during reprogramming. EPHA7 expression is directly regulated by OCT3/4. EphA7 knockdown results in marked reduction of reprogramming efficiency, and the addition of truncated EPHA7 is able to restore it. ERK activity is markedly reduced during reprogramming, and the secreted, truncated EPHA7 is responsible for ERK activity reduction. Remarkably, treatment of EphA7-knockdown MEFs with the ERK pathway inhibitor restores reprogramming efficiency. Analyses show that truncated EPHA7-induced ERK activity reduction plays an important role in the middle phase of reprogramming. Thus, our findings uncover the importance of secreted EPHA7-induced ERK activity reduction in reprogramming., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Members of the Eph/ephrin gene families act as key regulators of cerebellar development during embryogenesis. Aberrant signaling of Eph family of receptor tyrosine kinases and their ephrin ligands has also been implicated in human cancers. Medulloblastoma is an aggressive primitive neuroectodermal tumor that originates from granule neuron precursors in the cerebellum. Previous studies have suggested a role for the ephrin-A5 ligand and its receptors, EphA4 and EphA7, in granule cell-precursor formation and in guiding cell migration. In the present study, we investigated the effects of genetic loss of ephrin-A5, EphA4, and EphA7 on the spatiotemporal development of medulloblastoma tumors in the context of the smoothened transgenic mouse model system., Findings: Radiographic magnetic resonance imaging (MRI) was performed to monitor tumor growth in a genetically engineered mouse model of medulloblastoma. Tumor tissue was harvested to determine changes in the expression of phosphorylated Akt by Western blotting. This helped to establish a correlation between genotype and/or tumor size and survival. Our in vivo data establish that in ND2-SmoA1 transgenic mice, the homozygous deletion of ephrin-A5 resulted in a consistent pattern of tumor growth inhibition compared to their ephrin-A5 wild-type littermate controls, while the loss of EphA4/EphA7 failed to produce consistent effects versus EphA4/EphA7 wild-type mice. A positive correlation was evident between tumor size, p-Akt, and proliferating cell nuclear antigen (PCNA) expression in our transgenic mouse model system, regardless of genotype., Conclusions: Taken together, our findings underscore the importance of targeting specific members of the Eph/ephrin families in conjunction with the Akt pathway in order to inhibit medulloblastoma tumor growth and progression.

The aim of this study was to identify potential microRNAs and genes associated with drug resistance in ovarian cancer through web-available microarrays. The drug resistant-related microRNA microarray dataset GS54665 and mRNA dataset GSE33482, GSE28646, and GSE15372 were downloaded from the Gene Expression Omnibus database. Dysregulated microRNAs/genes were screened with GEO2R and were further identified in SKOV3 (SKOV3/DDP) and A2780 (A2780/DDP) cells by real-time quantitative PCR (qRT-PCR), and then their associations with drug resistance was analyzed by comprehensive bioinformatic analyses. Nine microRNAs (microRNA-199a-5p, microRNA-199a-3p, microRNA-199b-3p, microRNA-215, microRNA-335, microRNA-18b, microRNA-363, microRNA-645 and microRNA-141) and 38 genes were identified to be differentially expressed in drug-resistant ovarian cancer cells, with seven genes (NHSL1, EPHA3, USP51, ZSCAN4, EPHA7, SNCA and PI15) exhibited exactly the same expression trends in all three microarrays. Biological process annotation and pathway enrichment analysis of the 9 microRNAs and 38 genes identified several drug resistant-related signaling pathways, and the microRNA-mRNA interaction revealed the existence of a targeted regulatory relationship between the 9 microRNAs and most of the 38 genes. The expression of 9 microRNAs and the 7 genes by qRT-PCR in SKOV3/DDP and A2780/DDP cells indicating a consistent expression profile with the microarrays. Among those, the expression of EPHA7 and PI15 were negatively correlated with that of microRNA-141, and they were also identified as potential targets of this microRNA via microRNA-mRNA interaction. We thus concluded that microRNA-141, EPHA7, and PI15 might jointly participate in the regulation of drug resistance in ovarian cancer and serve as potential targets in targeted therapies.

Aims: This study aimed to investigate the expression of EphA7 in human laryngeal squamous cell carcinoma (LSCC) tissues and disclose the potential roles and molecular mechanisms of EphA7 in LSCC., Methods: In the present study, we examined EphA7 expression and its function and mechanism in LSCC. EphA7 expression levels were investigated by quantitative real-time PCR (qRT-PCR), western blotting, and immunohistochemistry in a panel of 35 LSCC patient cases. To investigate the potential mechanism of EphA7 in human laryngeal cancer, we employed EphA7 siRNA to knockdown EphA7 expression in LSCC cell line Hep-2 and AMC-HN-8. Subsequently, MTT, TUNEL, qRT-PCR, and western blotting were performed to disclose the roles of EphA7 on proliferation, invasion and migration, and apoptosis in LSCC cell line Hep-2 and AMC-HN-8., Results: Depletion of EphA7 remarkably inhibited the proliferation and invasion of Hep-2 and AMC-HN-8 cells in comparison to control and EphA7 siRNA negative control (NC)-transfected cells. TUNEL staining assay demonstrated that, compared with the control group, the rate of apoptosis in the EphA7 siRNA group was significantly increased. In addition, knockdown of EphA7 in Hep-2 or AMC-HN-8 cells markedly decreased the expression of EphA7 and PTEN, which could contribute to apoptosis. However, the bpV(phen), a PTEN inhibitor, could attenuate anti-proliferation and pro-apoptotic effects of EphA7 siRNA in Hep-2 and AMC-HN-8 cells., Conclusion: Up-regulation of EphA7 was observed in human LSCC samples and down-regulation of EphA7 effectively suppressed laryngeal carcinoma cell growth and promoted its apoptosis. Thus, EphA7 has a critical role in modulating cell growth and apoptosis, which serves as a potential therapeutic target in human LSCC., (© 2015 S. Karger AG, Basel.)

MicroRNAs (miRNAs) are short non-coding RNAs, which negatively regulate gene expression. Post‑transcriptional regulation by miRNAs is important for organism development. In addition, endothelial cells are key regulators of angiogenesis. By using the 3-(4,5-dimethylthiazol-2-yl)‑2,5‑diphenyltetrazolium bromide (MTT), migration and gelatin sponge-chorioallantoic membrane assays, it was demonstrated that when miR-137 was overexpressed, cell viability and migration decreased. In addition, it was observed that blocking endogenous miR-137 increased cell viability and migration. Bioinformatics analysis indicated that the 3'‑untranslated region (3'UTR) of the ephrin type-A receptor 7 (EPHA7) has a putative binding site for miR-137. miR-137 is able to directly bind to the EPHA7 3'UTR and negatively regulate the expression of EPHA7. miR-137 is also able to decrease the growth and migration of human umbilical vein endothelial cells (HUVECs). The identification of the function of miR-137 and its target gene EPHA7 in HUVECs may provide novel insights into the mechanisms of angiogenesis.

The first genome-wide association study of dental caries focused on primary teeth in children aged 3 to 12 yr and nominated several novel genes: ACTN2, EDARADD, EPHA7, LPO, MPPED2, MTR, and ZMPSTE24. Here we interrogated 156 single-nucleotide polymorphisms (SNPs) within these candidate genes for evidence of association with dental caries experience in 13 race- and age-stratified samples from 6 independent studies (n = 3600). Analysis was performed separately for each sample, and results were combined across samples via meta-analysis. MPPED2 was significantly associated with caries via meta-analysis across the 5 childhood samples, with 4 SNPs showing significant associations after gene-wise adjustment for multiple comparisons (p < .0026). These results corroborate the previous genome-wide association study, although the functional role of MPPED2 in caries etiology remains unknown. ACTN2 also showed significant association via meta-analysis across childhood samples (p = .0014). Moreover, in adults, genetic association was observed for ACTN2 SNPs in individual samples (p < .0025), but no single SNP was significant via meta-analysis across all 8 adult samples. Given its compelling biological role in organizing ameloblasts during amelogenesis, this study strengthens the hypothesis that ACTN2 influences caries risk. Results for the other candidate genes neither proved nor precluded their associations with dental caries., (© International & American Associations for Dental Research.)

Mutations leading to activation of proto-oncogenic protein kinases (PKs) are a type of drivers crucial for understanding tumorogenesis and as targets for antitumor drugs. However, bioinformatics tools so far developed to differentiate driver mutations, typically based on conservation considerations, systematically fail to recognize activating mutations in PKs. Here, we present the first comprehensive analysis of the 407 activating mutations described in the literature, which affect 41 PKs. Unexpectedly, we found that these mutations do not associate with conserved positions and do not directly affect ATP binding or catalytic residues. Instead, they cluster around three segments that have been demonstrated to act, in some PKs, as "molecular brakes" of the kinase activity. This finding led us to hypothesize that an auto inhibitory mechanism mediated by such "brakes" is present in all PKs and that the majority of activating mutations act by releasing it. Our results also demonstrate that activating mutations of PKs constitute a distinct group of drivers and that specific bioinformatics tools are needed to identify them in the numerous cancer sequencing projects currently underway. The clustering in three segments should represent the starting point of such tools, a hypothesis that we tested by identifying two somatic mutations in EPHA7 that might be functionally relevant., (© 2013 WILEY PERIODICALS, INC.)

Synpolydactyly 1(SPD1) is a dominantly inherited distal limb anomaly that is characterized by incomplete digit separation and increased number of digits. SPD1 is most commonly caused by polyalanine repeat expansions and mutations in the homeodomain of the HOXD13. We report a splice donor site mutation in HOXD13 associated in most cases with cortical bone thinning. In vitro study of transcripts and truncated protein analysis indicated that c.781+1G>A mutation results in truncated HOXD13 protein p.G190fsX4. Luciferase assay indicated that the truncated HOXD13 protein failed to bind to DNA. The mechanism for this phenotype was truncated protein loss of function., (© 2013.)

Prior studies have identified two anatomically and neurochemically distinct cellular compartments within the mammalian striatum, termed striosomes and matrix, which express μ-opioid receptors (μOR) and EphA4, respectively. Here we identify and characterize an additional compartment in the rat striatum composed of neurons that express EphA7. In situ hybridization and immunohistochemical data indicate that neurons expressing EphA7 mRNA and protein are arranged in a banded "matrisome-like" pattern confined to the matrix in the dorsal striatum. Within the ventral striatum, EphA7-positive (+) neurons have a less organized mosaic pattern that partially overlaps areas expressing μOR. Immunolabeling data demonstrate that EphA7+ striatofugal axons form distinct fascicles leaving the striatum. Within the globus pallidus, EphA7+ axons terminate primarily within ventromedial areas of the nucleus and along its striatal border. EphA7+ axons avoid regions containing dopamine neurons within the substantia nigra and preferentially innervate areas near the rostral and caudal margins of the nucleus. Within both nuclei, EphA7+ axons have similar but more restricted terminal fields than the entire population of EphA4+ matrix axons, indicating that EphA7+ axons comprise a subpopulation of matrix axons. Ligand binding data demonstrate that ephrin-A5 selectively binds areas of the striatum, globus pallidus, and substantia nigra containing EphA7+ neurons and axons, but not areas expressing only EphA4. Our findings demonstrate that EphA7 expression identifies a novel "matrisome" compartment within the matrix that binds ephrin-A5 and possesses unique axonal projections. Our findings also suggest that EphA7 and ephrin-A5 may participate in the formation of this matrisome subcompartment and its striatofugal projections., (Copyright © 2013 Wiley Periodicals, Inc., A Wiley Company.)

Recent technological advances allow analysis of genomic changes in cancer in unprecedented detail. The next challenge is to prioritize the multitude of genetic aberrations found and identify therapeutic opportunities. We recently completed a study that illustrates the use of unbiased genetic screens and murine cancer models to find therapeutic targets among complex genomic data. We genetically dissected the common deletion of chromosome 6q and identified the ephrin receptor A7 (EPHA7) as a tumor suppressor in lymphoma. Notably, EPHA7 encodes a soluble splice variant that acts as an extrinsic tumor suppressor. Accordingly, we developed an antibody-based strategy to specifically deliver EPHA7 back to tumors that have lost this gene. Recent sequencing studies have implicated EPHA7 in lung cancer and other tumors, suggesting a broader therapeutic potential for antibody-mediated delivery of this tumor suppressor for cancer therapy. Together, our comprehensive approach provides new insights into cancer biology and may directly lead to the development of new cancer therapies., (© 2013 New York Academy of Sciences.)

A previous study showed that the EphA7 receptor regulates apoptotic cell death during early brain development. In this study, we provide evidence that the EphA7 receptor interacts with death receptors such as tumor necrosis factor receptor 1 (TNFR1) to decrease cell viability. We showed that ephrinA5 stimulates EphA7 to activate the TNFR1-mediated apoptotic signaling pathway. In addition, a pull-down assay using biotinylated ephrinA5-Fc revealed that ephrinA5-EphA7 complexes recruit TNFR1 to form a multi-protein complex. Immunocytochemical staining analysis showed that EphA7 was co-localized with TNFR1 on the cell surface when cells were incubated with ephrinA5 at low temperatures. Finally, both the internalization motif and death domain of TNFR1 was important for interacting with an intracytoplasmic region of EphA7; this interaction was essential for inducing the apoptotic signaling cascade. This result suggests that a distinct multi-protein complex comprising ephrinA5, EphA7, and TNFR1 may constitute a platform for inducing caspase-dependent apoptotic cell death.

Auditory stimulus representations are dynamically maintained by ascending and descending projections linking the auditory cortex (Actx), medial geniculate body (MGB), and inferior colliculus. Although the extent and topographic specificity of descending auditory corticofugal projections can equal or surpass that of ascending corticopetal projections, little is known about the molecular mechanisms that guide their development. Here, we used in utero gene electroporation to examine the role of EphA receptor signaling in the development of corticothalamic (CT) and corticocollicular connections. Early in postnatal development, CT axons were restricted to a deep dorsal zone (DDZ) within the MGB that expressed low levels of the ephrin-A ligand. By hearing onset, CT axons had innervated surrounding regions of MGB in control-electroporated mice but remained fixed within the DDZ in mice overexpressing EphA7. In vivo neurophysiological recordings demonstrated a corresponding reduction in spontaneous firing rate, but no changes in sound-evoked responsiveness within MGB regions deprived of CT innervation. Structural and functional CT disruption occurred without gross alterations in thalamocortical connectivity. These data demonstrate a potential role for EphA/ephrin-A signaling in the initial guidance of corticofugal axons and suggest that "genetic rewiring" may represent a useful functional tool to alter cortical feedback without silencing Actx.

Homeodomain-containing transcription factors Dlx5 and Msx2 are able to form a heterodimer, and together can regulate embryonic development including skeletogenesis. Dlx5 functions as a transcriptional activator and Msx2 a transcriptional repressor, and they share common target genes. During mouse digit development, the expression domains of Dlx5 and Msx2 overlap at the distal region of the developing terminal phalange, although digit formation and regeneration are not altered in the Dlx5 and Msx2 null mutant embryos. Interestingly, we observed a high rate of defects in neural tube formation in Dlx5 and Msx2 double null mutants. In the absence of both Dlx5 and Msx2, a high occurrence of exencephaly and severe defects in craniofacial morphology are observed. Additionally, Dlx5 and Msx2 expression domain analysis showed overlap of the genes at the apex of the neural folds just prior to neural fold fusion. The expression patterns of ephrinA5 and two isoforms of EphA7 were tested as downstream targets of Dlx5 and Msx2. Results show that EphrinA5 and the truncated isoform of EphA7 are regulated by Dlx5 and Msx2 together, although the full length isoform of EphA7 expression is not altered. Overall, these data show that Dlx5 and Msx2 play a critical role in controlling cranial neural tube morphogenesis by regulating cell adhesion via the ephrinA5 and EphA7 pathway., (© 2013 The Authors Development, Growth & Differentiation © 2013 Japanese Society of Developmental Biologists.)

Introduction: Pulpitis has been associated with abundant inflammatory cells, dilated blood vessels, and thickening nerve fibers histopathologically with or without severe pain clinically. On the basis of EphA7 receptor expression in inflammatory cells, the developing mouse dental pulp, and trigeminal nerve system, EphA7 may possibly be involved in local inflammatory response and sensory innervation of adult dental pulp as well as odontogenic pain conducted through the trigeminal system. The purpose of the study was to analyze the expression of EphA7 gene in healthy and inflamed human dental pulps and to elucidate the roles of EphA7 gene in dental pulp inflammation response and odontogenic pain., Methods: Twelve healthy controls, 5 acute pulpitis from dental trauma, 21 symptomatic, and 20 asymptomatic irreversible pulpitis human dental pulps were involved in the study. The protein expression, subcellular localization, and mRNA level of EphA7 gene were detected by immunohistochemistry and real-time reverse transcriptase-polymerase chain reaction, respectively., Results: In healthy samples, immunohistochemical staining showed positive EphA7 expression only in vascular endothelial cells and odontoblasts with cytoplasm staining. Under inflammatory conditions, in addition to the above cells, EphA7 staining began to occur in fibroblasts, nerve fiber tissues, and inflammatory cells. Compared with healthy samples, EphA7 expressions at both mRNA and protein levels increased significantly in acute and irreversible pulpitis samples. In asymptomatic irreversible pulpitis samples, EphA7 expressions were significantly lower than those in symptomatic ones but still higher than those in healthy ones. There was no significant difference between acute and symptomatic irreversible pulpitis groups., Conclusions: The results suggest that EphA7 gene may be a marker reflecting inflammatory activity and pain state for human dental pulp., (Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

The functional annotation of the cancer genome can reveal new opportunities for cancer therapies. The wealth of genomic data on various cancers has not yet been mined for clinically and therapeutically useful information. We use cross-comparisons of genomic data with the results of unbiased genetic screens to prioritize genomic changes for further study. In this manner, we have identified a soluble variant of the ephrin receptor A7 (EPHA7 (TR) ) as a tumor suppressor that is lost in lymphoma. We also developed antibody-based delivery to restore this tumor suppressor to the cancer cells in situ. We will discuss our strategy of screening genomic data, specific findings concerning EPHA7 and the potential for future discoveries.

Cryptic deletions at chromosome 6q are common cytogenetic abnormalities in T-cell lymphoblastic leukemia/lymphoma (T-LBL), but the target genes have not been formally identified. Our results build on detection of specific chromosomal losses in a mouse model of γ-radiation-induced T-LBLs and provide interesting clues for new putative susceptibility genes in a region orthologous to human 6q15-6q16.3. Among these, Epha7 emerges as a bona fide candidate tumor suppressor gene because it is inactivated in practically all the T-LBLs analyzed (100% in mouse and 95.23% in human). We provide evidence showing that Epha7 downregulation may occur, at least in part, by loss of heterozygosity (19.35% in mouse and 12.5% in human) or promoter hypermethylation (51.61% in mouse and 43.75% in human) or a combination of both mechanisms (12.90% in mouse and 6.25% in human). These results indicate that EPHA7 might be considered a new tumor suppressor gene for 6q deletions in T-LBLs. Notably, this gene is located in 6q16.1 proximal to GRIK2 and CASP8AP2, other candidate genes identified in this region. Thus, del6q seems to be a complex region where inactivation of multiple genes may cooperatively contribute to the onset of T-cell lymphomas.

A hallmark of mammalian evolution is the structural and functional complexity of the cerebral cortex. Within the cerebral cortex, the neocortex, or isocortex, is a 6-layered complexly organized structure that is comprised of multiple interconnected sensory and motor areas. These areas and their precise patterns of connections arise during development, through a process termed arealization. Intrinsic, activity-independent and extrinsic, activity-dependent mechanisms are involved in the development of neocortical areas and their connections. The intrinsic molecular mechanisms involved in the establishment of this sophisticated network are not fully understood. In this report (I) and the companion report (II), we present the first lifespan analysis of ipsilateral intraneocortical connections (INCs) among multiple sensory and motor regions, from the embryonic period to adulthood in the mouse. Additionally, we characterize the neocortical expression patterns of several developmentally regulated genes that are of central importance to studies investigating the molecular control of arealization from embryonic day 13.5 to postnatal day (P) 3 (I) and P6 to 50 (II). In this analysis, we utilize novel methods to correlate the boundaries of gene expression with INCs and developing areal boundaries, in order to better understand the nature of gene-areal relationships during development.

The mammalian neocortex contains an intricate processing network of multiple sensory and motor areas that allows the animal to engage in complex behaviors. These anatomically and functionally unique areas and their distinct connections arise during early development, through a process termed arealization. Both intrinsic, activity-independent and extrinsic, activity-dependent mechanisms drive arealization, much of which occurs during the areal patterning period (APP) from late embryogenesis to early postnatal life. How areal boundaries and their connections develop and change from infancy to adulthood is not known. Additionally, the adult patterns of sensory and motor ipsilateral intraneocortical connections (INCs) have not been thoroughly characterized in the mouse. In this report and its companion (I), we present the first lifespan analysis of ipsilateral INCs among multiple sensory and motor regions in mouse. We describe the neocortical expression patterns of several developmentally regulated genes that are of central importance to studies investigating the molecular regulation of arealization, from postnatal day (P) 6 to P50. In this study, we correlate the boundaries of gene expression patterns with developing areal boundaries across a lifespan, in order to better understand the nature of gene-areal relationships from early postnatal life to adulthood.

Previous studies suggest that EphA7 plays a critical role in neural tube closure or cortical progenitor apoptosis. In this report, enhancer trap assay was used to modify various EphA7 BAC clones and screen a large genomic region spanning 570 kb downstream of the EphA7 gene. We found that the dorsal midline-specific EphA7 enhancer resides on the 457D20 EphA7 BAC clone and is localized to a 35 kb genomic region in between +345.7 kb to +379.8 kb downstream of the EphA7 transcription start site. Identification of the EphA7 BAC clone containing a long-range dorsal midline enhancer may constitute a useful tool for investigating the biological functions of EphA7 in vivo.

Pre-clinical studies provide compelling evidence that Eph family receptor tyrosine kinases (RTKs) and ligands promote cancer growth, neovascularization, invasion, and metastasis. Tumor suppressive roles have also been reported for the receptors, however, creating a potential barrier for clinical application. Determining how these observations relate to clinical outcome is a crucial step for translating the biological and mechanistic data into new molecularly targeted therapies. We investigated eph and ephrin expression in human breast cancer relative to endpoints of overall and/or recurrence-free survival in large microarray datasets. We also investigated protein expression in commercial human breast tissue microarrays (TMA) and Stage I prognostic TMAs linked to recurrence outcome data. We found significant correlations between ephA2, ephA4, ephA7, ephB4, and ephB6 and overall and/or recurrence-free survival in large microarray datasets. Protein expression in TMAs supported these trends. While observed no correlation between ephrin ligand expression and clinical outcome in microarray datasets, ephrin-A1 and EphA2 protein co-expression was significantly associated with recurrence in Stage I prognostic breast cancer TMAs. Our data suggest that several Eph family members are clinically relevant and tractable targets for intervention in human breast cancer. Moreover, profiling Eph receptor expression patterns in the context of relevant ligands and in the context of stage may be valuable in terms of diagnostics and treatment.

Recent genome-wide association studies (GWASs) have identified candidate genes contributing to cancer risk through low-penetrance mutations. Many of these genes were unexpected and, intriguingly, included well-known players in carcinogenesis at the somatic level. To assess the hypothesis of a germline-somatic link in carcinogenesis, we evaluated the distribution of somatic gene labels within the ordered results of a breast cancer risk GWAS. This analysis suggested frequent influence on risk of genetic variation in loci encoding for "driver kinases" (i.e., kinases encoded by genes that showed higher somatic mutation rates than expected by chance and, therefore, whose deregulation may contribute to cancer development and/or progression). Assessment of these predictions using a population-based case-control study in Poland replicated the association for rs3732568 in EPHB1 (odds ratio (OR) = 0.79; 95% confidence interval (CI): 0.63-0.98; P(trend) = 0.031). Analyses by early age at diagnosis and by estrogen receptor α (ERα) tumor status indicated potential associations for rs6852678 in CDKL2 (OR = 0.32, 95% CI: 0.10-1.00; P(recessive) = 0.044) and rs10878640 in DYRK2 (OR = 2.39, 95% CI: 1.32-4.30; P(dominant) = 0.003), and for rs12765929, rs9836340, rs4707795 in BMPR1A, EPHA3 and EPHA7, respectively (ERα tumor status P(interaction)<0.05). The identification of three novel candidates as EPH receptor genes might indicate a link between perturbed compartmentalization of early neoplastic lesions and breast cancer risk and progression. Together, these data may lay the foundations for replication in additional populations and could potentially increase our knowledge of the underlying molecular mechanisms of breast carcinogenesis.

Gastrointestinal stromal tumours (GISTs) are sarcomas arising in the gastrointestinal tract. They are characterised by a gain in function mutation of the KIT oncogene and the majority express the receptor tyrosine kinase KIT, which can be detected by the immunohistochemical stain CD117. Patients with a GIST present with symptoms such as abdominal pain or gastrointestinal bleeding, or may be asymptomatic. We describe the clinical history and pathological features of a patient with a GIST who presented with a paratesticular mass which, to our knowledge, has never previously been reported. With the development of new drugs to treat GISTs, the knowledge of the type of mutations may in the future prove helpful in determining optimal treatment strategies and prognosis.

EphA7 is a member of Eph/ephrins family and play diverse roles in carcinogenesis. The aim of our study was to investigate functional and structural alterations of EphA7 in prostate cancer and determine if those findings correlate with the clinicopathologic features of prostate cancer. Forty-eight prostate carcinomas, 31 benign prostate hyperplasias, 5 normal prostate tissues and 3 prostate cell lines (LNCaP, DU145 and PC-3) were examined with quantitative RT-PCR, methylation-specific PCR and immunohistochemistry. Downregulation or loss of EphA7 mRNA expression was detected in 23 of 48 (47.9%) prostate carcinomas, and 2 of 31 (6.5%) hyperplasias. Methylation of the EphA7 promoter region was present in 20 of 48 (41.7%) of carcinomas and 6 of 31 (19.3%) hyperplasias, respectively. Immunostaining analysis showed EphA7 protein was absent in 10 of 30 (33.3%) carcinoma samples available and 8 of them (80.0%) exhibited hypermethylation. The frequency of EphA7 methylation was higher in cancer patients with higher Gleason score. Treatment of DU145 cells harboring methylation with 5-aza-2'-deoxycytidine reactivated expression of EphA7. Ectopic expression of EphA7 in DU145 cells did not suppress cell growth but inhibited colony formation. Our study provides evidence that epigenetic inactivation of EphA7 may be involved in prostate carcinogenesis.