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Janes et al. developed an anti-ADAM10 mAb (8C7) that binds to an active form of ADAM10 present in tumors, particularly in stem-like cells. Administration of 8C7 inhibits Notch activity and tumor growth in mouse models, including regrowth after chemotherapy., The transmembrane metalloprotease ADAM10 sheds a range of cell surface proteins, including ligands and receptors of the Notch, Eph, and erbB families, thereby activating signaling pathways critical for tumor initiation and maintenance. ADAM10 is thus a promising therapeutic target. Although widely expressed, its activity is normally tightly regulated. We now report prevalence of an active form of ADAM10 in tumors compared with normal tissues, in mouse models and humans, identified by our conformation-specific antibody mAb 8C7. Structure/function experiments indicate mAb 8C7 binds an active conformation dependent on disulfide isomerization and oxidative conditions, common in tumors. Moreover, this active ADAM10 form marks cancer stem-like cells with active Notch signaling, known to mediate chemoresistance. Importantly, specific targeting of active ADAM10 with 8C7 inhibits Notch activity and tumor growth in mouse models, particularly regrowth after chemotherapy. Our results indicate targeted inhibition of active ADAM10 as a potential therapy for ADAM10-dependent tumor development and drug resistance.

Background Pulmonary hypertension is a heterogeneous disease, and a significant portion of patients at risk for it have CT imaging available. Advanced automated processing techniques could be leveraged for early detection, screening, and development of quantitative phenotypes. Pruning and vascular tortuosity have been previously described in pulmonary arterial hypertension (PAH), but the extent of these phenomena in arterial vs venous pulmonary vasculature and in exercise pulmonary hypertension (ePH) have not been described. Research Question What are the arterial and venous manifestations of pruning and vascular tortuosity using CT imaging in PAH, and do they also occur in ePH? Study Design and Methods A cohort of patients with PAH and ePH and control subjects with available CT angiograms were retrospectively identified to examine the differential arterial and venous presence of pruning and tortuosity in patients with precapillary pulmonary hypertension not confounded by lung or thromboembolic disease. The pulmonary vasculature was reconstructed, and an artificial intelligence method was used to separate arteries and veins and to compute arterial and venous vascular volumes and tortuosity. Results A total of 42 patients with PAH, 12 patients with ePH, and 37 control subjects were identified. There was relatively lower (median [interquartile range]) arterial small vessel volume in subjects with PAH (PAH 14.7 [11.7-16.5; P < .0001]) vs control subjects (16.9 [15.6-19.2]) and venous small vessel volume in subjects with PAH and ePH (PAH 8.0 [6.5-9.6; P < .0001]; ePH, 7.8 [7.5-11.4; P = .004]) vs control subjects (11.5 [10.6-12.2]). Higher large arterial volume, however, was only observed in the pulmonary arteries (PAH 17.1 [13.6-23.4; P < .0001] vs control subjects 11.4 [8.1-15.4]). Similarly, tortuosity was higher in the pulmonary arteries in the PAH group (PAH 3.5 [3.3-3.6; P = .0002] vs control 3.2 [3.2-3.3]). Interpretation Lower small distal pulmonary vascular volume, higher proximal arterial volume, and higher arterial tortuosity were observed in PAH. These can be quantified by using automated techniques from clinically acquired CT scans of patients with ePH and resting PAH., Graphical Abstract

Eph receptor tyrosine kinases play a key role in cell-cell communication. Lack of structural information on the entire multi-domain intracellular region of any Eph receptor has hindered understanding of their signaling mechanisms. Here, we use integrative structural biology to investigate the structure and dynamics of the EphA2 intracellular region. EphA2 promotes cancer malignancy through a poorly understood non-canonical form of signaling involving serine/threonine phosphorylation of the linker connecting its kinase and SAM domains. We show that accumulation of multiple linker negative charges, mimicking phosphorylation, induces cooperative changes in the EphA2 intracellular region from more closed to more extended conformations and perturbs the EphA2 juxtamembrane segment and kinase domain. In cells, linker negative charges promote EphA2 oligomerization. We also identify multiple kinases catalyzing linker phosphorylation. Our findings suggest multiple effects of linker phosphorylation on EphA2 signaling and imply that coordination of different kinases is necessary to promote EphA2 non-canonical signaling., Eph receptor tyrosine kinases and their ephrin ligands mediate cell-cell communication. Here, the authors assess the structure and dynamics of the EphA2 intracellular region and uncover complex effects of phosphorylation within the linker region between EphA2 kinase and SAM domains.

Oncogenic Ras mutations are frequently observed in solid tumor cells and are present in pancreatic cancer, colorectal cancer (CRC), and lung cancer (LC) [1, 2]. Mutational activation of K-Ras in these tissues is sufficient to initiate neoplasia in mice [3–5]. Thus, understanding the mechanisms behind Ras-induced oncogenesis is an important goal in cancer therapy. A significant consequence of Ras-mediated signal transduction is the altered expression of a large number of genes. It is well established that canonical Ras signaling is coupled to transcriptional regulation through the activation of the MAPK cascade, which involves the sequential phosphorylation and activation of the serine/threonine kinases RAF, MEK1/2, and ERK1/2 [6–12]. More recently, new regulatory factors that directly interact with K-Ras were identified and shown to play a crucial role in the full range of K-Ras oncogenic phenotypes [13–19]. Despite decades of effort, many aspects of the molecular mechanism underlying Ras-induced tumorigenesis and possible therapeutic targeting remain difficult to identify. Ephexin1 is a member of the DbI family of guanine nucleotide exchange factors (GEFs) and serves as a direct link between Eph receptors and the Rho-family of GTPases [20, 21]. Ephexin1 is highly expressed in the nervous system during development and is involved in many neurophysiological events [22–26]. It is phosphorylated by the Src family of kinases and by fibroblast growth factor receptor signaling, leading to the regulation of GEF activity, which in turn regulates actin cytoskeletal dynamics [22, 27]. Through extensive analysis of the gene expression patterns in cells with activated forms of Ras and Rho families, it was found that Ephexin1 was highly upregulated by H-RasG12V in NIH3T3 cells [28]. In humans, Ephexin1 is upregulated in papillary thyroid cancers (PTC) and has been identified as the most reliable marker for PTC diagnosis [29]. Therefore, the implication of these results is that Ephexin1 may be involved in tumor proliferation and progression, particularly in cancer cells with oncogenic Ras mutations. However, the functional consequences of Ephexin1 had not yet been addressed. In the present study, we show that Ephexin1 is overexpressed in both CRC and LC tissues and is associated with a poor prognosis for both cancers, and provide evidence for the functional and clinical significance of Ephexin1 and identify a potential therapeutic target for the case of CRC and LC caused by Ras mutations.

The paper is an interpretation of Eph 1:15-23 which is a consequence of the shorter version of Eph 1:15 (without the words: τὴν ἀγάπην). It is an attempt to answer the question of who the “saints” are in this verse and the entire pericope, what background (Hellenistic or Judaic) this concept has, and what was the character of the church community in this city in the post-Pauline period. The method used in this paper consists of historical and contextual analysis of lexicographical end ideological material used in the pericope. The first step is a study of the rhetorical structure of Eph as the instrument for interpretation of the role of the pericope in the meaning of the text. The second part of the paper is presented the binary way of exposition: in the language of Judaism and in the Hellenistic terms. From this perspective the category of “saints” is described. From this analysis it is concluded: “saints” are the group belonging to the Judeo-Christian component of the Church, the political substructure of the Church but not in terms of the separation, but of the pluralistic unity.

The widespread disagreement about where the Ephesian household code begins is largely based on an equally widespread agreement that the original text of Eph 5.22 has no verb. This article addresses the former by challenging the latter. Treating the textual problem as a choice between three rather than two readings means that ὑποτασσέσθωσαν emerges as the reading that is best attested, the more difficult, and the one that best explains the others. The result is a smooth flow throughout this section of Ephesians.

Rapid tumor progression, metastasis, and diagnosis in advanced stages of disease are the main reasons for the short survival time and high mortality rate of patients with hepatocellular carcinoma (HCC). Ephrin A4 (EFNA4), the ligand of the EPH family, participates in the development of blood vessels and epithelium by regulating cell migration and rejection. In our study, based on bioinformatics analyses, we found that EFNA4 was highly expressed and led to poor prognosis in patients with HCC. We demonstrated that overexpression of EFNA4 significantly promoted HCC cell proliferation and migration in vivo or in vitro. In addition, knockdown of EFNA4 inhibited the proliferation and migration of HCC cells. Furthermore, EFNA4 was found to directly interact with EPHA2 and promote its phosphorylation at Ser897, followed by recruitment of phosphoinositide-3-kinase regulatory subunit 2 (PIK3R2) and activation of the glycogen synthase kinase-3beta (GSK3β)/β-catenin signaling pathway. Moreover, overexpression of β-catenin further promoted the expression of PIK3R2, which formed a positive feedback loop. The results revealed that abnormal expression of EFNA4 is the main switch of the PIK3R2/GSK3β/β-catenin loop that influenced the proliferation and migration of HCC cells and suggest that EFNA4 is a potential prognostic marker and a prospective therapeutic target in patients with HCC., Graphical abstract, EFNA4 is an oncogene that negatively relates to the clinical prognosis in HCC patients. Abnormal expression of EFNA4 would contribute to HCC proliferation and migration by activating a GSK3β-β-catenin-PIK3R2 positive feedback loop. Thus, clarification of the mechanism of EFNA4 would be helpful for providing a new therapeutic target for HCC patients.

[Image: see text] Erythropoietin-producing hepatocellular (Eph) receptors are receptor tyrosine kinases involved in cell–cell contact. The EphA2 receptor is associated with cancer proliferation and migration. Therefore, EphA2 receptor imaging has the potential for cancer diagnosis. Here, we synthesized N-(5-((4-((4-ethylpiperazin-1-yl)methyl)-3-(trifluoromethyl)phenyl)carbamoyl)-2-methylphenyl)-5-[(123)I]iodonicotinamide ([(123)I]ETB) and evaluated it as an imaging tracer for single-photon emission computed tomography (SPECT) imaging of the EphA2 receptor. [(123)I]ETB was designed on the basis of ALW-II-41-27, an inhibitor of EphA2 receptor kinase. Nonradioactive ETB was also synthesized and has been shown to efficiently inhibit EphA2 receptor kinase activity in vitro (IC(50): ETB, 90.2 ± 18.9 nM). A cell-binding assay demonstrated that [(125)I]ETB binds specifically to the EphA2 receptor. The ex vivo biodistribution study of [(125)I]ETB in U87MG tumor-bearing mice also revealed tumor uptake (2.2% ID/g at 240 min). In addition, [(123)I]ETB uptake in tumors was visualized via SPECT/CT imaging. On the basis of the above, [(123)I]ETB can be considered a potential SPECT imaging tracer for the EphA2 receptor.

Lipid droplet (LD) accumulation in cancer results from aberrant metabolic reprograming due to increased lipid uptake, diminished lipolysis and/or de novo lipid synthesis. Initially implicated in storage and lipid trafficking in adipocytes, LDs are more recently recognized to fuel key functions associated with carcinogenesis and progression of several cancers, including prostate cancer (PCa). However, the mechanisms controlling LD accumulation in cancer are largely unknown. EPHB2, a tyrosine kinase (TKR) ephrin receptor has been proposed to have tumor suppressor functions in PCa, although the mechanisms responsible for these effects are unclear. Given that dysregulation in TRK signaling can result in glutaminolysis we postulated that EPHB2 might have potential effects on lipid metabolism. Knockdown strategies for EPHB2 were performed in prostate cancer cells to analyze the impact on the net lipid balance, proliferation, triacylglycerol-regulating proteins, effect on LD biogenesis, and intracellular localization of LDs. We found that EPHB2 protein expression in a panel of human-derived prostate cancer cell lines was inversely associated with in vivo cell aggressiveness. EPHB2 silencing increased the proliferation of prostate cancer cells and concurrently induced de novo LD accumulation in both cytoplasmic and nuclear compartments as well as a “shift” on LD size distribution in newly formed lipid-rich organelles. Lipid challenge using oleic acid exacerbated the effects on the LD phenotype. Loss of EPHB2 directly regulated key proteins involved in maintaining lipid homeostasis including, increasing lipogenic DGAT1, DGAT2 and PLIN2 and decreasing lipolytic ATGL and PEDF were observed with EPHB2 silencing. A DGAT1-specific inhibitor abrogated LD accumulation and proliferative effects induced by EPHB2 loss. In conclusion, we highlight a new anti-tumor function of EPHB2 in lipid metabolism through regulation of DGAT1 and ATGL in prostate cancer. Blockade of DGAT1 in EPHB2-deficient tumors appears to be effective in restoring the lipid balance and reducing tumor growth.

In the past two decades, significant progress has been made in the past two decades towards the understanding of the basic mechanisms underlying cancer growth and angiogenesis. In this context, receptor tyrosine kinases (RTKs) play a pivotal role in cell proliferation, differentiation, growth, motility, invasion, and angiogenesis, all of which contribute to tumor growth and progression. Mutations in RTKs lead to abnormal signal transductions in several pathways such as Ras-Raf, MEK-MAPK, PI3K-AKT and mTOR pathways, affecting a wide range of biological functions including cell proliferation, survival, migration and vascular permeability. Increasing evidence demonstrates that multiple kinases are involved in angiogenesis including RTKs such as vascular endothelial growth factor, platelet derived growth factor, epidermal growth factor, insulin-like growth factor-1, macrophage colony-stimulating factor, nerve growth factor, fibroblast growth factor, Hepatocyte Growth factor, Tie 1 & 2, Tek, Flt-3, Flt-4 and Eph receptors. Overactivation of RTKs and its downstream regulation is implicated in tumor initiation and angiogenesis, representing one of the hallmarks of cancer. This review discusses the role of RTKs, PI3K, and mTOR, their involvement, and their implication in pro-oncogenic cellular processes and angiogenesis with effective approaches and newly approved drugs to inhibit their unrestrained action.

Objectives The aim of this study is to investigate the underlying mechanism of the recovery of periodontal ligament cells (PDLCs) sequentially exposed to inflammation and mechanical loading. Materials and methods We divided PDLCs into four groups: control; compressive force (CF) alone (2.0 g/cm2 ); lipopolysaccharides (LPS) pre-treatment (0.1 μg/ml) followed by simultaneous LPS and CF stimulation, simulating uncontrolled periodontitis; and LPS pre-treatment followed by CF exposure, simulating controlled periodontitis. The expression of EphB4-ephrinB2 and EphA2-ephrinA2, and the level of osteoclastogenesis and osteogenesis were evaluated. Results Simultaneous stimulation by LPS and CF, compared with CF alone and sequential LPS and CF exposure, significantly suppressed EphB4 and enhanced ephrinA2 expression. Similarly, the most intense osteoclastic differentiation was observed under simultaneous LPS and CF stimulation, whilst sequential exposure to LPS and CF only slightly increased osteoclastic cell numbers. Both the activation of EphB4 signaling and ephrinA2 silencing lowered osteoclastic differentiation, which had previously been upregulated by simultaneous LPS and CF stimulation. These treatments also increased osteogenic differentiation. Conclusions Simultaneous LPS and CF stimulation critically enhances osteoclastogenesis in PDLCs through the suppression of EphB4 and the induction of ephrinA2 signaling. Sequential LPS and CF exposure partially abolishes the osteolytic effects of simultaneous stimulation.

Objective: This study aimed to evaluate the frequency of episodic primary headaches (EPH) and temporomandibular dysfunction’s (TMD) effect in experienced scuba divers.Methods: A form consisting of ...

Background Ephrin-A2, a member of the Eph receptor subgroup, is used in diagnosing and determining the prognosis of prostate cancer. However, the role of ephrin-A2 in prostate cancer is still unclear. Methods We established stable clones overexpressing or silencing ephrin-A2 from prostate cancer cells. Then, CCK-8 was used in analyzing the proliferation ability of cells. CD31 staining was used in evaluating angiogenesis. Migration and invasion assay were conducted in vivo and in vitro. The expression of EMT-related markers was evaluated in prostate cancer cells through Western blotting. Results We revealed that the ectopic expression of ephrin-A2 in prostate cancer cells facilitated cell migration and invasion in vitro and promoted tumor metastasis and angiogenesis in vivo and that the silencing of ephrin-A2 completely reversed this effect. Although ephrin-A2 did not affect tumor cell proliferation in vitro, ephrin-A2 significantly promoted primary tumor growth in vivo. Furthermore, to determine the biological function of ephrin-A2, we assayed the expression of EMT-related markers in stable established cell lines. Results showed that the overexpression of ephrin-A2 in prostate cancer cells down-regulated the expression of epithelial markers (ZO-1, E-cadherin, and claudin-1) and up-regulated the expression of mesenchymal markers (N-cadherin, β-catenin, vimentin, Slug, and Snail), but the knocking out of ephrin-A2 opposed the effects on the expression of EMT markers. Conclusions These findings indicate that ephrin-A2 promotes prostate cancer metastasis by enhancing angiogenesis and promoting EMT and may be a potentially therapeutic target in metastatic prostate cancer.

To assemble the functional circuits of the nervous system, the neuronal axonal growth cones must be precisely guided to their proper targets, which can be achieved through cell–surface guidance receptor activation by ligand binding in the periphery. We investigated the function of paxillin, a focal adhesion protein, as an essential growth cone guidance intermediary in the context of spinal lateral motor column (LMC) motor axon trajectory selection in the limb mesenchyme. Usingin situmRNA detection, we first show paxillin expression in LMC neurons of chick and mouse embryos at the time of spinal motor axon extension into the limb. Paxillin loss-of-function and gain-of-function usingin ovoelectroporation in chick LMC neurons, of either sex, perturbed LMC axon trajectory selection, demonstrating an essential role of paxillin in motor axon guidance. In addition, a neuron-specific paxillin deletion in mice led to LMC axon trajectory selection errors. We also show that knocking down paxillin attenuates the growth preference of LMC neurites against ephrinsin vitro, and erythropoietin-producing human hepatocellular (Eph)-mediated retargeting of LMC axonsin vivo, suggesting paxillin involvement in Eph-mediated LMC motor axon guidance. Finally, both paxillin knockdown and ectopic expression of a nonphosphorylable paxillin mutant attenuated the retargeting of LMC axons caused by Src overexpression, implicating paxillin as a Src target in Eph signal relay in this context. In summary, our findings demonstrate that paxillin is required for motor axon guidance and suggest its essential role in the ephrin–Eph signaling pathway resulting in motor axon trajectory selection.SIGNIFICANCE STATEMENTDuring the development of neural circuits, precise connections need to be established among neurons or between neurons and their muscle targets. A protein family found in neurons, Eph, is essential at different stages of neural circuit formation, including nerve outgrowth and pathfinding, and is proposed to mediate the onset and progression of several neurodegenerative diseases, such as Alzheimer's disease. To investigate how Ephs relay their signals to mediate nerve growth, we investigated the function of a molecule called paxillin and found it important for the development of spinal nerve growth toward their muscle targets, suggesting its role as an effector of Eph signals. Our work could thus provide new information on how neuromuscular connectivity is properly established during embryonic development.

Objectives Vein graft adaptation (VGA) is a process that vein as a vascular graft conduits in arterial reconstructive surgery; VGA can lead to postoperative vein graft stenosis (VGS) and complications after coronary artery bypass graft and other peripheral artery bypass surgeries. VGA is characterized by vein graft loss the venous features without exhibiting arterial features; furthermore, the activation of ERK inhibited the maintenance of venous properties of the vein graft. We hypothesized that ERK inhibition can affect vein VGS through regulating the expression of EphB4. Methods Rat vein transplantation model was established using wild-type and EphB4+/− Sprague-Dawley rats. Hematoxylin-eosin, Masson, Verhoeff, actin staining, and immunohistochemistry were applied to observe the structure of the vein grafts. Vascular smooth muscle cells (VSMCs) were isolated from the vein and vein grafts. Western blotting was used to determine the expression of p-ERK1/2 and EphB4, and immunofluorescence was applied to detect the expression and location of EphB4. Cell wound scratch assay and CCK8 assay were used to determine the migration and proliferation of VSMCs. Real-time polymerase chain reaction was used to determine the mRNA expression of EphB4. Results Western blotting in vein sample and vein graft sample detected p-ERK1/2 and ERK1/2 expression in both EphB4+/+ and EphB4+/− rats. The expression of p-ERK was increased in vein graft compared to vein. Immunofluorescence in VSMCs form EphB4+/+ and EphB4+/− rats detected EphB4 expression in both cells, and the expression of EphB4 was increased in VSMCs form EphB4+/+ rats. SCH772984 reduces the proliferation and migration of VSMCs. Inhibition of ERK suppressed the increase of vein graft wall thickness, and the expression of collagen fibers, elastic fibers, and α-actin was decreased. Vein graft from EphB4+/− rats reduces the expression of EphB4, and SCH772984 suppressed the decrease of EphB4 in vivo. Vein graft from EphB4+/− rats increased the expression of EphB4, and SCH772984 suppressed the increase of EphB4 in vivo. Conclusions The inhibition of ERK1/2 suppressed the process of VGS by decreasing the proliferation of VSMCs. The ERK-inhibitor SCH772984 suppressed the level of VGS by extending the time of EphB4 expression during the process of VGA, thus maintaining the venousization of vein graft. The mechanism may be that the inhibitor SCH772984 suppresses the level of VGS by extending the time of EphB4 expression during the process of VGA. Therefore, our research provides a new target of VGS treatment by inhibiting the expression of ERK1/2 through the process of VGA.

To investigate the effect of surgical procedure on the operation's results in patients undergoing emergency peripartum hysterectomy (EPH).The records of patients who underwent EPH due to postpartum hemorrhage between 2010 and 2020 in two tertiary centers with a high crude delivery rate were retrospectively analyzed. Surgical data were compared according to the EPH type.During the study period, 115,709 births occurred in these two centers. EPH was administered for 181 (1.6%) of these patients. Sixty-seven (37%) of the EPH cases involved subtotal EPH (SEPH), and 114 (63%) were total EPH (TEPH). Surgical time (107.3 ± 17.6 vs. 134.2 ± 32.3 min,According to the results, if the bleeding in peripartum hemorrhage requiring EPH can be controlled with SEPH, attempting to remove the cervix completely may be associated with increased surgical time, blood transfusion need, and surgical complications.

ErbB2 is overexpressed in approximately 25% of human breast cancers, associated with clinically aggressive disease. No soluble ligand has been identified and the receptor is regulated by heterodimerization with other ErbB family receptors, including EGFR, and other receptor tyrosine kinases including EphA2. EGFR is activated by seven different growth factors including EGF and Amphiregulin. Downstream signaling modules required for ErbB2 induced tumorigenesis in genetically engineered mouse models (GEMM) include the phosphatidylinositol 3-kinase/Akt (PKB) pathway, the Ras/Raf/MEK/ERK1/2 pathway and the phospholipase C (PLCγ) pathways. ErbB2-mediated tumorigenesis involves activation of receptor tyrosine kinases, induction of cyclin D1/CDK activity, and functional restraint by tumor suppressors. The receptor tyrosine kinase EPH receptor A2 (EphA2), a member of the Eph RTK family, is overexpressed in aggressive breast cancer and EphA2 forms a complex with ErbB2 thereby enhancing ErbB2-induced tumor onset and progression. The host immune system participates in the therapeutic response of HER2+ breast cancer. The tumor microenvironment (TME) is regulated by chemokines and their G protein coupled receptors binds several ligands, including Cxcl5 which binds Cxcr2, to augment the pro-tumor immune response, tumor growth and metastasis. Identifying genetic programs that participate in ErbB2-induced tumors may provide the rational basis for co-extinction therapeutic approaches. Peroxisome proliferator-activated receptor γ (PPARγ), which is expressed in a variety of malignancies, governs biological functions through transcriptional programs. Herein, genetic deletion of endogenous Pparγ1 restrained mammary tumor progression, lipogenesis, and induced local mammary tumor F4/80+ tumor-associated macrophage infiltration, without affecting other tissue hematopoietic stem cell pools. Pparγ1 induced peroxisomal target genes in the mammary tumors as evidenced by increased expression of PEX-11, together with PPARGC1 and ESRR induced regulator, muscle 1, Perm1 (PGC-1 and ERR-induced Regulator in Muscle 1). Peroxisomes induced by Pparγ1, activated Type1 interferons (IFNs) and IFN-stimulated gene expression, including Cxcl5. Endogenous Pparγ1 induced expression of both an EphA2-Amphiregulin and an inflammatory INFγ -Cxcl5 signaling module. Pparγ1 bound directly to growth promoting and proinflammatory target genes in the context of chromatin. We conclude Pparγ1 promotes ErbB2-induced tumor growth and inflammation and represents a relevant target for therapeutic coextinction. Citation Format: Richard G Pestell, Xuanmao Jiao, Andrew V Kossenkov, Adam Ertel, Wei Tong, Zhao Zhang, Peter A McCue. Pparg1 induces an EGF-EphA2 receptor tyrosine kinase module to promote ErbB2- mammary adenocarcinoma in mice [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS17-58.

Background A critical and challenging process in immunotherapy is to identify cancer patients who could benefit from immune checkpoint inhibitors (ICIs). Exploration of predictive biomarkers could help to maximize the clinical benefits. Eph receptors have been shown to play essential roles in tumor immunity. However, the association between EPH gene mutation and ICI response is lacking. Methods Clinical data and whole-exome sequencing (WES) data from published studies were collected and consolidated as a discovery cohort to analyze the association between EPH gene mutation and efficacy of ICI therapy. Another independent cohort from Memorial Sloan Kettering Cancer Center (MSKCC) was adopted to validate our findings. The Cancer Genome Atlas (TCGA) cohort was used to perform anti-tumor immunity and pathway enrichment analysis. Results Among fourteen EPH genes, EPHA7-mutant (EPHA7-MUT) was enriched in patients responding to ICI therapy (FDR adjusted P n = 386), significant differences were detected between EPHA7-MUT and EPHA7-wildtype (EPHA7-WT) patients regarding objective response rate (ORR, 52.6% vs 29.1%, FDR adjusted P = 0.0357) and durable clinical benefit (DCB, 70.3% vs 42.7%, FDR adjusted P = 0.0200). In the validation cohort (n = 1144), significant overall survival advantage was observed in EPHA7-MUT patients (HR = 0.62 [95% confidence interval, 0.39 to 0.97], multivariable adjusted P = 0.0367), which was independent of tumor mutational burden (TMB) and copy number alteration (CNA). Notably, EPHA7-MUT patients without ICI therapy had significantly worse overall survival in TCGA cohort (HR = 1.33 [95% confidence interval, 1.06 to 1.67], multivariable adjusted P = 0.0139). Further gene set enrichment analysis revealed enhanced anti-tumor immunity in EPHA7-MUT tumor. Conclusions EPHA7-MUT successfully predicted better clinical outcomes in ICI-treated patients across multiple cancer types, indicating that EPHA7-MUT could serve as a potential predictive biomarker for immune checkpoint inhibitors.

Focal adhesion kinase (FAK), human myofibrillogenesis regulator-1 (MR-1), ephrin receptor type A4 (EphA4), proto-oncogene tyrosine kinase Src (Src), and protein kinase C (PKC) are important markers in proliferation, survival, and migration in some cancers. However, the significance of each is still unclear in different malignancies, including acute myeloid leukemia (AML). Therefore, this study was conducted to investigate their serum levels in Egyptian adult de novo AML patients (n = 70) against healthy volunteers (n = 20). We managed to study the correlation between each pair and to investigate their association with diagnosis, prognosis, and survival. Serum levels were analyzed using enzyme-linked immunosorbent assay (ELISA). We found that FAK, MR-1, Src, and PKC serum levels were significantly higher in AML patients compared to control (p

Ephrin type-A receptor 10 (EPHA10) has been implicated as a potential target for breast and prostate cancer therapy. However, its involvement in oral squamous cell carcinoma (OSCC) remains unclear. We demonstrated that EPHA10 supports in vivo tumor growth and lymphatic metastasis of OSCC cells. OSCC cell migration, epithelial mesenchymal transition (EMT), and sphere formation were found to be regulated by EPHA10, and EPHA10 was found to drive expression of some EMT- and stemness-associated transcription factors. Among EPHA10 ligands, exogenous ephrin A4 (EFNA4) induced the most OSCC cell migration and sphere formation, as well as up-regulation of SNAIL, NANOG, and OCT4. These effects were abolished by extracellular signal-regulated kinase (ERK) inhibition and NANOG knockdown. Also, EPHA10 was required for EFNA4-induced cell migration, sphere formation, and expression of NANOG and OCT4 mRNA. Our microarray dataset revealed that EFNA4 mRNA expression was associated with expression of NANOG and OCT4 mRNA, and OSCC patients showing high co-expression of EFNA4 with NANOG or OCT4 mRNA demonstrated poor recurrence-free survival rates. Targeting forward signaling of the EFNA4-EPHA10 axis may be a promising therapeutic approach for oral malignancies, and the combination of EFNA4 mRNA and downstream gene expression may be a useful prognostic biomarker for OSCC.

"The aim of this paper is to study the cycles of EPH geometries through their omogeneous gradient-type deformations recently introduced by the author. A special topic is the orthogonality between a given cycle $C$ and its deformations as well as between $C$ and its rotated version $R(C)$."

Adolescent alcohol drinking is widely recognized as a significant public health problem, and evidence is accumulating that sufficient levels of consumption during this critical period of brain development have an enduring impact on neural and behavioral function. Recent studies have indicated that adolescent intermittent ethanol (AIE) exposure alters astrocyte function, astrocyte-neuronal interactions, and related synaptic regulation and activity. However, few of those studies have included female animals, and a broader assessment of AIE effects on the proteins mediating astrocyte-mediated glutamate dynamics and synaptic function is needed. We measured synaptic membrane expression of several such proteins in the dorsal and ventral regions of the hippocampal formation (DH, VH) from male and female rats exposed to AIE or adolescent intermittent water. In the DH, AIE caused elevated expression of glutamate transporter 1 (GLT-1) in both males and females, elevated postsynaptic density 95 expression in females only, and diminished NMDA receptor subunit 2A expression in males only. AIE and sex interactively altered ephrin receptor A4 (EphA4) expression in the DH. In the VH, AIE elevated expression of the cystine/glutamate antiporter and the glutamate aspartate transporter 1 (GLAST) in males only. Compared to males, female animals expressed lower levels of GLT-1 in the DH and greater levels of ephrin receptor B6 (EphB6) in the VH, in the absence of AIE effects. These results support the growing literature indicating that adolescent alcohol exposure produces long-lasting effects on astrocyte function and astrocyte-neuronal interactions. The sex and subregion specificity of these effects have mechanistic implications for our understanding of AIE effects generally.

The present study investigated the participation of D-serine and NR2 in antinociception produced by blockade of central erythropoietin-producing hepatocellular carcinoma (Eph) A4 (EphA4) signaling in rats with trigeminal neuropathic pain. Trigeminal neuropathic pain was modeled in male Sprague-Dawley rats using mal-positioned dental implants. The left mandibular second molar was extracted under anesthesia, and a miniature dental implant was placed to induce injury to the inferior alveolar nerve. Our current findings showed that nerve injury induced by malpositioned dental implants significantly produced mechanical allodynia; additionally, the inferior alveolar nerve injury increased the expression of D-serine and NR2 subunits in the ipsilateral medullary dorsal horn (trigeminal subnucleus caudalis). Intracisternal administration of EphA4-Fc, an EphA4 inhibitor, inhibited nerve injury-induced mechanical allodynia and upregulated the expression of D-serine and NR2 subunits. Moreover, intracisternal administration of D-amino acids oxidase, a D-serine inhibitor, inhibited trigeminal mechanical allodynia. These results show that D-serine and NR2 subunit pathways participate in central EphA4 signaling after an inferior alveolar nerve injury. Therefore, blockade of D-serine and NR2 subunit pathways in central EphA4 signaling provides a new therapeutic target for the treatment of trigeminal neuropathic pain.

Ephrins are ligands of Eph receptors (Ephs); both of which are sorted into two classes, A and B. There are five types of ephrin-As (ephrin-A1–5) and three types of ephrin-Bs (ephrin-B1–3). Also, there are 10 types of EphAs (EphA1–10) and six types of EphBs (EphB1–6). Binding of ephrins to the Eph receptors activates signaling cascades that regulate several biological processes such as cellular proliferation, differentiation, migration, angiogenesis, and vascular remodeling. Clarification of their roles in the female reproductive system is crucial to understanding the physiology and pathology of this system. Such knowledge will also create awareness regarding the importance of these molecules in diagnostic, prognostic, and therapeutic medicine. Hence, we have discussed the involvement of these molecules in the physiological and pathological events that occur within the female reproductive system. The evidence so far suggests that the ephrins and the Eph receptors modulate folliculogenesis, ovulation, embryo transport, implantation, and placentation. Abnormal expression of some of these molecules is associated with polycystic ovarian syndrome, ovarian cancer, tubal pregnancy, endometrial cancer, uterine leiomyoma (fibroids), cervical cancer, and preeclampsia, suggesting the need to utilize these molecules in the clinical setting. To enhance a quick development of this gradually emerging field in female reproductive medicine, we have highlighted some “gaps in knowledge” that need prospective investigation.

BACKGROUND Recent studies have revealed that ephrin receptor (EPH) is implicated in important signal transduction of cancer development and progression. EPHB2 is expressed in human cancer, and reported to be related to the prognosis of colorectal, gastric and breast cancer. This meta-analysis was systematically assessed the prognostic roles of EPHB2 expression in patients with cancer. PATIENTS AND METHODS PubMed, Embase and Cochrane library were searched for eligible studies up to May 2020. Pooled hazard ratio (HR) and 95% confidence interval (CI) were calculated to evaluate the relationship of EPHB2 expression with overall and disease-free survival in patients with cancer. RESULTS The pooled HRs for low expression of EPHB2 were 1.65 (95% CI=1.30-2.09, p

The erythropoietin-producing human hepatocellular (Eph) receptors are transmembrane glycoprotein members of the tyrosine kinase receptors family. The Ephs may bind to various ephrin ligands resulting in the phosphorylation of their tyrosine kinase domain and the activation of the Eph receptor. In this review we focus on EphA3, one receptor of the 14 different Ephs, as it carries out both redundant and restricted functions in the germline development of mammals and in the maintenance of various adult tissues. The loss of EphA3 regulation is correlated with various human malignancies, the most notable being cancer. This receptor is overexpressed and/or mutated in multiple tumors, and is also associated with poor prognosis and decreased survival in patients. Here we highlight the role of EphA3 in normal and malignant tissues that are specific to cancer; these include hematologic disorders, gastric cancer, glioblastoma multiforme, colorectal cancer, lung cancer, renal cell carcinoma, and prostate cancer. Moreover, various anticancer agents against EphA3 have been developed to either inhibit its kinase domain activity or to function as agonists. Thus, we examine the most potent small molecule drugs and mAb-based therapeutics against EphA3 that are currently in pre-clinical or clinical stages.

The aggressive nature of glioblastoma multiforme (GBM) may be attributed to the dysregulation of pathways driving both proliferation and invasion. EphrinB2, a membrane-bound ligand for some of the Eph receptors, has emerged as a critical target regulating these pathways. In this study, we investigated the role of ephrinB2 in regulating proliferation and invasion in GBM using intracranial and subcutaneous xenograft models. The Cancer Genome Atlas analysis suggested high transcript and low methylation levels of ephrinB2 as poor prognostic indicators in GBM, consistent with its role as an oncogene. EphrinB2 knockdown, however, increased tumor growth, an effect that was reversed by ephrinB2 Fc protein. This was associated with EphB4 receptor activation, consistent with the data showing a significant decrease in tumor growth with ephrinB2 overexpression. Mechanistic analyses showed that ephrinB2 knockdown has anti-invasive but pro-proliferative effects in GBM. EphB4 stimulation following ephrinB2 Fc treatment in ephrinB2 knockdown tumors was shown to impart strong anti-proliferative and anti-invasive effects, which correlated with decrease in PCNA, p-ERK, vimentin, Snail, Fak, and increase in the E-cadherin levels. Overall, our study suggests that ephrinB2 cannot be used as a sole therapeutic target. Concomitant inhibition of ephrinB2 signaling with EphB4 activation is required to achieve maximal therapeutic benefit in GBM.

In the past decade, there have been extensive efforts to open up the Eph/ephrin subfamily of the receptor tyrosine kinase family for diagnostic and therapeutic applications. Besides classical pharmaceutical developments, which focus either on drugs targeting the extracellular ligand binding domains or on the intracellular tyrosine kinase domains of these receptors, there also have been first radiopharmaceutical approaches. Here the focus is on the development of specific and selective probes for molecular imaging, particularly by means of positron emission tomography, and the functional characterization of the Eph/ephrin subfamily in certain target tissues. The aim of this mini-review is to summarize the different approaches toward Eph-targeting radiotracers by using antibodies, peptides, and small molecules and to discuss their radiopharmacological characterization. With regard to the small molecules, further considerations will focus on the design and synthesis of nonradioactive reference compounds and precursors as well as on radiolabeling strategies.

Background Although the Eph receptor plays an important role in the development of neuropathic pain following nerve injury, there has been no evidence of the participation of the ephrin A4 receptor (EphA4) in the development of trigeminal neuropathic pain. The present study investigated the role of EphA4 in central nociceptive processing in rats with inferior alveolar nerve injury. Materials and methods Male Sprague-Dawley rats were used in all our experiments. A rat model for trigeminal neuropathic pain was produced using malpositioned dental implants. The left mandibular second molar was extracted under anesthesia, followed by the placement of a miniature dental implant to injure the inferior alveolar nerve. Results Our current findings show that nerve injury induced by malpositioned dental implants evokes significant mechanical allodynia and up-regulation of EphA4 expression in the ipsilateral trigeminal subnucleus caudalis. Although daily treatment with EphA4-Fc, an EphA4 antagonist, did not produce prolonged anti-allodynic effects after the chronic neuropathic pain had been already established, an early treatment protocol with repeated EphA4-Fc administration significantly attenuated mechanical allodynia before initiation of chronic neuropathic pain. Finally, we confirmed the participation of the central EphA4 pathway in the development of trigeminal neuropathic pain by reducing EphA4 expression using EphA4 siRNA. This suppression of EphA4 produced significantly prolonged anti-allodynic effects. Conclusion These results suggest that early blockade of central EphA4 signaling provides a new therapeutic target for the treatment of trigeminal neuropathic pain.

The aim of this research is to explore the relationship between intrapersonal conflict among administration employees of the Public Hospital Enterprise (EPH) Houari-Boumadian Kaser El Hirane located in the Wilaya of Laghouat and their individual work performance. Survey data was collected from 59 respondent and analysed using structural equation modelling using PLS methodology. The result of the study after the statistical analysis using the programme (Smart PLS 3.0) revealed that there is a strong impact of intrapersonal conflict and individual work performance.

Serum protein electrophoresis (EPH) is used to assess relative concentrations of blood proteins in clinical and biological studies. Serum EPH fractions have been determined for elasmobranchs using mammalian albumin, alpha 1-, alpha 2-, beta-, and gamma-globulin fractions, and have been deemed fractions 1 through 5, respectively. However, serum EPH fraction concentration reference intervals (RIs) have not been widely established for different elasmobranch species. In this study, RIs for fractions 1 through 5 were determined from 45 wild-caught Nurse Sharks Ginglymostoma cirratum (27 females and 23 males) in South Florida. Serum samples were isolated from whole blood following caudal venipuncture. Body condition was also measured in the field to assess the relative health of the individuals sampled. There was no relationship between body condition and serum EPH fraction concentrations. In addition, there was no difference in body condition or serum EPH fraction concentrations between females and males. Total solids and total protein values were significantly different (P < 0.001). Nurse Shark serum EPH fraction 1 was found within the mammalian albumin migrating band distance and was negligible. Fraction 2 showed no peak in the mammalian alpha 1-globulin range. A thin, medium peak in the mammalian alpha 2-globulin range represented fraction 3. In the mammalian beta-globulin range, fraction 4 consisted of the majority of protein observed. It was represented by a smooth, broad peak. A short, medium broad peak in the mammalian gamma-globulin range represented fraction 5. The Nurse Shark serum EPH fraction RIs provided in this study may be utilized to clinically evaluate the health of Nurse Sharks in captivity and in the wild, and to compare the health of their populations around the world experiencing various anthropogenic stressors and other environmental impacts.

Pseudoenzymes are present within many, but not all, known enzyme families and lack one or more conserved canonical amino acids that help define their catalytically active counterparts. Recent findings in the pseudokinase field confirm that evolutionary repurposing of the structurally defined bilobal protein kinase fold permits distinct biological functions to emerge, many of which rely on conformational switching, as opposed to canonical catalysis. In this analysis, we evaluate progress in evaluating several members of the ‘dark’ pseudokinome that are pertinent to help drive this expanding field. Initially, we discuss how adaptions in erythropoietin‐producing hepatocellular carcinoma (Eph) receptor tyrosine kinase domains resulted in two vertebrate pseudokinases, EphA10 and EphB6, in which co‐evolving sequences generate new motifs that are likely to be important for both nucleotide binding and catalysis‐independent signalling. Secondly, we discuss how conformationally flexible Tribbles pseudokinases, which have radiated in the complex vertebrates, control fundamental aspects of cell signalling that may be targetable with covalent small molecules. Finally, we show how species‐level adaptions in the duplicated canonical kinase protein serine kinase histone (PSKH)1 sequence have led to the appearance of the pseudokinase PSKH2, whose physiological role remains mysterious. In conclusion, we show how the patterns we discover are selectively conserved within specific pseudokinases, and that when they are modelled alongside closely related canonical kinases, many are found to be located in functionally important regions of the conserved kinase fold. Interrogation of these patterns will be useful for future evaluation of these, and other, members of the unstudied human kinome., Here, we evaluate several families of poorly studied 'dark' kinases and pseudokinases using a bioinformatic and structural analysis approach. Our investigation revealed several new features of two erythropoietin‐producing hepatocellular carinoma (Eph) psedudokinases: EphA10 and EphB6. Furthermore, we discuss newly identified features of the Tribbles pseudokinases as well as the unique pseudokinase protein serine kinase histone 2 (PSKH2).

Eph receptors are a family of receptor tyrosine kinases that control directional cell movement during various biological processes, including embryogenesis, neuronal pathfinding, and tumor formation. The biochemical pathways of Eph receptors are context-dependent in part because of the varied composition of a heterotypic, oligomeric, active Eph receptor complex. Downstream of the Eph receptors, little is known about the essential phosphorylation events that define the context and instruct cell movement. Here, we define a pathway that is required for Eph receptor B2 (EphB2)–mediated cell sorting and is conserved among multiple Eph receptors. Utilizing a HEK293 model of EphB2(+)/ephrinB1(+) cell segregation, we found that the scaffold adaptor protein SH2 domain–containing adaptor protein B (Shb) is essential for EphB2 functionality. Further characterization revealed that Shb interacts with known modulators of cytoskeletal rearrangement and cell mobility, including Nck adaptor protein (Nck), p120-Ras GTPase-activating protein (RasGAP), and the α- and β-Chimaerin Rac GAPs. We noted that phosphorylation of Tyr(297), Tyr(246), and Tyr(336) of Shb is required for EphB2–ephrinB1 boundary formation, as well as binding of Nck, RasGAP, and the chimaerins, respectively. Similar complexes were formed in the context of EphA4, EphA8, EphB2, and EphB4 receptor activation. These results indicate that phosphotyrosine-mediated signaling through Shb is essential in EphB2-mediated heterotypic cell segregation and suggest a conserved function for Shb downstream of multiple Eph receptors.

Erythropoietin-producing hepatocellular receptors (Eph) promote the onset and sustain the progression of cancers such as colorectal cancer (CRC), in which the A2 subtype of Eph receptor expression has been shown to correlate with a poor prognosis and has been identified as a promising therapeutic target. Herein, we investigated, in vitro and in vivo, the effects of treatment with GLPG1790, a potent pan-Eph inhibitor. The small molecule has selective activity against the EphA2 isoform in human HCT116 and HCT15 CRC cell lines expressing a constitutively active form of RAS concurrently with a wild-type or mutant form of p53, respectively. GLPG1790 reduced EPHA2 phosphorylation/activation and induced G1/S cell-cycle growth arrest by downregulating the expression of cyclin E and PCNA, while upregulating p21Waf1/Cip1 and p27Cip/Kip. The inhibition of ephrin signaling induced quiescence in HCT15 and senescence in HCT116 cells. While investigating the role of CRC-related, pro-oncogenic p53 and RAS pathways, we found that GLPG1790 upregulated p53 expression and that silencing p53 or inhibiting RAS (human rat sarcoma)/ERKs (extracellular signal-regulated kinase) signaling restrained the ability of GLPG1790 to induce senescence in HCT116 cells. On the other hand, HCT15 silencing of p53 predisposed cells to GLPG1790-induced senescence, whilst no effects of ERK inhibition were observed. Finally, GLPG1790 hindered the epithelial-mesenchymal transition, reduced the migratory capacities of CRC, and affected tumor formation in xenograft models in vivo more efficiently using HCT116 than HCT15 for xenografts. Taken together, our data suggest the therapeutic potential of GLPG1790 as a signal transduction-based therapeutic strategy in to treat CRC.

Early Postpartum Hemorrhage (EPH) is one of the leading causes of postpartum mortality. It is defined as blood loss of at least 500 mL after vaginal or 1000 mL following cesarean delivery within 24 hours postpartum. The following paper includes literature review aimed to estimate the incidence and predictors of early postpartum hemorrhage (EPH). Available prevention and treatment methods were also assessed. The inclusion criteria for the study were met by 52 studies. The exact frequency of EPH in different populations varies from 1.2% to 12.5%. Maternal, pregnancy-associated, laborcorrelated and sociodemographic risk factors seem to be important predictors of EPH. In these cases appropriate prophylaxis should be considered. However, EPH may occur without previous risk factors. The main reason for EPH is uterine atony which contributes to up to 80% of cases of postpartum hemorrhage (PPH). Other common reasons for PPH include genital tract injuries, placenta accreta or coagulopathies. Interestingly, the majority of uterotonics seem to have a similar effect. However, carbetocin seems to be the most effective in certain situations. Appropriate diagnosis of EPH is the most important issue. The treatment should be causative. The first-line treatment should include uterotonics. Surgical interventions, if required, should be performed without delay, although preoperative uterine tamponade should be considered due to its high effectiveness. Medical staff training in medical simulation centers is an important factor that improves the outcomes of EPH treatment. It provides adaptation to hospital protocols, team work improvement, self-confidence building, more accurate blood loss evaluation and reduced perception of stress. The implementation of systematic trainings provides better outcomes in the future.

Eph receptor tyrosine kinases, particularly EphA2 and EphB4, represent promising candidates for molecular imaging due to their essential role in cancer progression and therapy resistance. Xanthine derivatives were identified to be potent Eph receptor inhibitors with IC50 values in the low nanomolar range (1-40 nm). These compounds occupy the hydrophobic pocket of the ATP-binding site in the kinase domain. Based on lead compound 1, we designed two fluorine-18-labelled receptor tyrosine kinase inhibitors ([18F]2/3) as potential tracers for positron emission tomography (PET). Docking into the ATP-binding site allowed us to find the best position for radiolabelling. The replacement of the methyl group at the uracil residue ([18F]3) rather than the methyl group of the phenoxy moiety ([18F]2) by a fluoropropyl group was predicted to preserve the affinity of the lead compound 1. Herein, we point out a synthesis route to [18F]2 and [18F]3 and the respective tosylate precursors as well as a labelling procedure to insert fluorine-18. After radiolabelling, both radiotracers were obtained in approximately 5% radiochemical yield with high radiochemical purity (>98%) and a molar activity of >10 GBq μmol-1. In line with the docking studies, first cell experiments revealed specific, time-dependent binding and uptake of [18F]3 to EphA2 and EphB4-overexpressing A375 human melanoma cells, whereas [18F]2 did not accumulate at these cells. Since both tracers [18F]3 and [18F]2 are stable in rat blood, the novel radiotracers might be suitable for in vivo molecular imaging of Eph receptors with PET.

Investigating the cellular and molecular mechanisms involved in the development of topographically ordered connections in the central nervous system constitutes an important issue in neurobiology because these connections are the base of the central nervous system normal function. The dominant model to study the development of topographic maps is the projection from the retinal ganglion cells to the optic tectum/colliculus. The expression pattern of Eph/ephrin system in opposing gradients both in the retina and the tectum, labels the local addresses on the target and gives specific sensitivities to growth cones according to their topographic origin in the retina. The rigid precision of normal retinotopic mapping has prompted the chemoaffinity hypothesis, positing axonal targeting to be based on fixed biochemical affinities between fibers and targets. However, several lines of evidence have shown that the mapping can adjust to experimentally modified targets with flexibility, demonstrating the robustness of the guidance process. Here we discuss the complex ways the Ephs and ephrins interact allowing to understand how the retinotectal mapping is a precise but also a flexible process. Fil: Medori, Mara Solange. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; Argentina Fil: Spelzini, Gonzalo Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; Argentina Fil: Scicolone, Gabriel Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; Argentina

Purpose: The initial step of cancer metastasis is that cancer cells acquire the capability to migrate and invade. Eph receptors comprise the largest family of receptor tyrosine and display dual role in tumor progression due to unique ephrin cis- or trans- signaling. The roles of EphB1 and its phosphorylation signaling in lung cancer remain to be elucidated. Patients and Methods: We analyzed the expression of EphB1 in both publicly available database and 60 cases of NSCLC patients with or without metastasis. The migration and invasion of lung cancer cells were assessed by a transwell assay. The activation of EphB1 signaling was assessed by western blot and real-time PCR. The EphB1 mutant was used to evaluate the effect of phosphorylation of EphB1. Results: Here, we showed that increased expression of EphB1 was detected in Non-Small-Cell Lung Cancer (NSCLC) biopies compared to non-cancer controls. Significant higher expression of EphB1 in lung biopsies were found in patients with metastasis compared to non-metastatic NSCLC patients. Higher EphB1 expression was correlated with poor patient survival in lung cancer. Overexpression of EphB1 promoted the migration and invasion of lung cancer cells. On the contrast, Ephrin-B2, a transmembrane ligand for EphB1 forward signaling, inhibited migration and invasion of lung cancer cells. TGF-β-activated Smad2 transcriptionally upregulated the endogenous expression of EphB1. Ligand-independent EphB1 promoted Epithelial-mesenchymal transition (EMT) through upregulating CDH2. Conclusion: Our results showed that the effect of EphB1 on the migration and invasion was context-specific and was dependent on EphB1 phosphorylation.

Background/Aim: Breast cancer cell lines consist of bulk tumor cells and a small proportion of stem-like cells. While the bulk cells are known to express a distinct combination of Eph receptors and ephrin ligands, the transcript profiles of stem-like cells in these cell lines have not been adequately characterized. The aim of this study was to determine Eph receptor/ephrin ligand profiles of cancer stem cells specific to a triple negative breast carcinoma cell line. Materials and Methods: The normal breast cell line MCF10A and the invasive breast carcinoma cell line MDA-MB-231 were used to isolate CD24(+)/CD24(–) cell populations. The profiles of Eph receptors and ephrin ligands were determined by real-time PCR and the relative abundance in bulk and stem cells were compared. Results: Based on the mean ∆CT values, the descending order of abundance was as follows. Ephrin-A5 > EPHA2 > (EPHA8, EPHB2) > ephrin-B2 > (EPHA7, EPHB4, ephrin-A4) > ephrin-A3 > ephrin-A1 > (EPHB3, ephrin-B1) > EPHA4 > EPHA1 > EPHA10. EPHA6 and ephrin-A2 transcripts were not detectable in stem cells from either cell line. The expression of EPHA4, EPHA7, EPHA8, and ephrin-A5 in MDA-MB-231 stem cells was up-regulated by 12, 20, ~500, and 6.5-fold respectively. Conclusion: The up-regulation of transcripts for EPHA8 and its cognate ligand, ephrin-A5, in the stem cells isolated from MDA-MB-231, suggest their involvement in the invasiveness of this cell line. Based on literature reports, we propose the role of EPHA8 and ephrin-A5 in MDA-MB-231 stem cells via the PI3K-AKT-mTOR pathway.

Introduction Emergency peripartum hysterectomy (EPH) is a foremost operation and is perpetually implemented in the presence of life intimidating hemorrhage during or immediately after abdominal or vaginal deliveries. The aim of this study was to review cases managed at the Department of Gynecology and Obstetrics at Jordan University Hospital (JUH). Material and methods All women who underwent EPH due to any cause in the period from January 2010, to December 2017 were included in the study. Data were collected retrospectively using the patients' files namelessly. Main measures: age, gravidity, parity, number of previous cesarean sections, previous uterine surgeries, indication for hysterectomy, complications, antepartum bleeding and the need for blood transfusion. Results In total, 74 cases of EPH were managed during the study period. The incidence of EPH ranged from 0.24 to 8.7 per 1000 deliveries. EPH was found to be more common following cesarean sections than vaginal deliveries. The prime indication was abnormal placentation, uterine atony, and uterine rupture. The risk factors included previous cesarean sections, scarred uteruses, multiparity, older age group. Maternal morbidity ranged from 26.5 to 31.5% and mortality from 0 to 12.5% with a mean of 4.8%. Conclusions EPH is the most demanding obstetric surgery performed in very tiresome circumstances of life threatening hemorrhage. The indication for EPH in recent years has changed from outdated uterine atony to abnormal placentation. Antenatal eagerness of the risk factors, engrossment of proficient obstetricians at an early stage of management and a prompt hysterectomy after adequate resuscitation would go a long way in tumbling morbidity and mortality.

Eph (erythropoietin-producing hepatoma) receptors and Ephrin ligands constitute the largest subfamily of receptor tyrosine kinase (RTK), which were first discovered in tumors. Heretofore, Eph protein has been shown to be involved in various tumor biological behaviors including proliferation and progression. The occurrence of specific types of tumor is closely related to the virus infection. Virus entry is a complex process characterized by a series of events. The entry into target cells is an essential step for virus to cause diseases, which requires the fusion of the viral envelope and host cellular membrane mediated by viral glycoproteins and cellular receptors. Integrin molecules are well known as entry receptors for most herpes viruses. However, in recent years, Eph receptors and their Ephrin ligands have been reported to be involved in virus infections. The main mechanism may be the interaction between Eph receptors and conserved viral surface glycoprotein, such as the gH/gL or gB protein of the herpesviridae. This review focuses on the relationship between Eph receptor family and virus infection that summarize the processes of viruses such as EBV, KSHV, HCV, RRV, etc., infecting target cells through Eph receptors and activating its downstream signaling pathways resulting in malignancies. Finally, we discussed the perspectives to block virus infection, prevention, and treatment of viral-related tumors via Eph receptor family.

Several mechanisms of resistance to inhibition of BRAF activity in melanoma cells have been described so far. Genetic studies have shown that mutations in MEK1 kinase (MAP kinase kinase), which result in constitutive activation of ERK kinase, result in resistance to treatment. Another mechanism of the acquired BRAF inhibition resistance is the accumulation of activating mutations in the NRAS oncogene, which drives the activation of CRAF. This in turn leads to a permanent activation of the signal transduction to MEK and ERK . Another important mechanism of resistance is the formation of variants of the BRAF V600E gene splicing, including variants that lack exons 4 to 8 containing the RAS -binding domain. The presence of the p61 BRAF V600E variant leads to the constitutive ERK signal, which is resistant to RAF inhibition. In addition, treatment resistance is affected by hyperactivation of tyrosine kinase receptors such as platelet-derived factor receptor β (PDFRβ), insulin-like growth factor 1 receptor (IGF-1R) and erythropoietin-producing hepatocellular receptors (EPH) – leading to the induction of the 3-phosphoinositol kinase pathway (PI3K) in patients treated with BRAF or MEK inhibitors. Another interesting path of BRAFi/MEKi resistance is over-expression of the epidermal growth factor receptor (EGFR) through ne­gative feedback in patients treated with BRAF inhibitors (BRAFi) – EGFR is not normally expressed in untreated melanomas.

Eph receptor (Eph) and ephrin signaling regulate fundamental developmental processes through both forward and reverse signaling triggered upon cell–cell contact. In vertebrates, they are both classified into classes A and B, and some representatives have been identified in many metazoan groups, where their expression and functions have been well studied. We have extended previous phylogenetic analyses and examined the presence of Eph and ephrins in the tree of life to determine their origin and evolution. We have found that 1) premetazoan choanoflagellates may already have rudimental Eph/ephrin signaling as they have an Eph-/ephrin-like pair and homologs of downstream-signaling genes; 2) both forward- and reverse-downstream signaling might already occur in Porifera since sponges have most genes involved in these types of signaling; 3) the nonvertebrate metazoan Eph is a type-B receptor that can bind ephrins regardless of their membrane-anchoring structure, glycosylphosphatidylinositol, or transmembrane; 4) Eph/ephrin cross-class binding is specific to Gnathostomata; and 5) kinase-dead Eph receptors can be traced back to Gnathostomata. We conclude that Eph/ephrin signaling is of older origin than previously believed. We also examined the presence of protein domains associated with functional characteristics and the appearance and conservation of downstream-signaling pathways to understand the original and derived functions of Ephs and ephrins. We find that the evolutionary history of these gene families points to an ancestral function in cell–cell interactions that could contribute to the emergence of multicellularity and, in particular, to the required segregation of cell populations., This work was supported by grants from the Spanish Ministries of Economy and Competitiveness (BFU2014-53128-R) and of Science, Innovation and Universities (RTI2018-096501-B-I00), Generalitat Valenciana (PROMETEO 2017/150) and the European Research Council (ERC AdG 322694) to M.A.N., who also acknowledges financial support from the Spanish State Research Agency (AEI), through BFU and RTI grants as above plus the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2017-0273). The first three grants (BFU, RTI and PROM) are cofinanced by the European Regional Development Fund, ERDF. D.G.W. was supported by the Francis Crick Institute, which receives its core funding from Cancer Research UK (FC001217), the UK Medical Research Council (FC001217), and the Wellcome Trust (FC001217).

Herpesviruses are ubiquitous viruses, specifically the Epstein Barr virus (EBV). EBV and Kaposi's sarcoma-associated herpesvirus (KSHV) establish their latency for a long period in B-cells and their reactivation instigates dreadful diseases from cancer to neurological modalities. The envelope glycoprotein of these viruses makes an attachment with several host receptors. For instance; glycoprotein 350/220, gp42, gHgL and gB of EBV establish an attachment with CD21, HLA-DR, Ephs, and other receptor molecules to hijack the B- and epithelial cell machinery. Ephs are reported recently as potent receptors for EBV entry into epithelial cells. Eph receptors play a role in the maintenance and control of various cellular processes including morphology, adhesion, proliferation, survival and differentiation. Alterations in the structure and expression of Eph and ephrin (Eph ligands) molecules is entangled with various pathologies including tumours and neurological complications. Along with Eph, integrins, NRP, NMHC are also key players in viral infections as they are possibly involved in viral transmission, replication and persistence. Contrarily, KSHV gH is known to interact with EphA2 and -A4 molecules, whereas in the case of EBV only EphA2 receptors are being reported to date. The ELEFN region of KSHV gH was involved in the interaction with EphA2, however, the interacting region of EBV gH is elusive. Further, the gHgL of KSHV and EBV form a complex with the EphA2 ligand-binding domain (LBD). Primarily by using gL both KSHV and EBV gHgL bind to the peripheral regions of LBD. In addition to γ-herpesviruses, several other viruses like Nipah virus, Cedar virus, Hepatitis C virus and Rhesus macaque rhadinovirus (RRV) also access the host cells via Eph receptors. Therefore, we summarise the possible roles of Eph and ephrins in virus-mediated infection and these molecules could serve as potential therapeutic targets., Highlights • Crucial understanding of human γ-herpesviruses entry mechanism. • Eph receptors relate to changed biomolecular profile upon EBV infection. • EBV association with neurological disorders. • Eph receptors could be an elegant drug for human γ-herpesviruses.

A distinct boundary exists between the progenitor cells in the basal limbal epithelium and the more differentiated corneal epithelial basal cells. We have shown that reciprocal expression patterns of EphA2 and Ephrin-A1 are likely to contribute to normal limbal-corneal epithelial compartmentalization as well as play a role in response to injury. How this signaling axis is regulated remains unclear. We have demonstrated that microRNAs (miRNAs) play critical roles in corneal epithelial wound healing and several miRNAs (e.g. miR-210) have been predicted to target Ephrins. Previous expression profiling experiments demonstrated that miR-210 is prominently expressed in corneal epithelial cells. RNA-seq data acquired from miR-210-depleted HCECs showed up-regulation of genes involved in cellular migration. In addition, miR-210 is decreased after corneal injury while EphA2 is increased. Moreover, antago-210-treated HCECs markedly enhanced wound closure in a scratch wound assay. Antago-210 treatment resulted in increased EphA2 protein levels as well as pS897-EphA2, the pro-migratory form of EphA2. As expected, Ephrin-A1 levels were reduced, while levels of a well-known target of miR-210, Ephrin-A3, were increased by antago-210 treatment. The increase in migration with antago-210 could be inhibited by Ephrin-A1 overexpression, Ephrin-A1-Fc treatment or siRNA depletion of EphA2. However, depletion of Ephrin-A3 did not have effects on the antago-210-induced increase in migration. In addition, Ephrin-A1 overexpression and siEphA2 dampened EGFR signaling, which is increased by antago-210. Our data clearly demonstrate a link between miR-210 and EphA2/Ephrin-A1 signaling that regulates, in part, corneal epithelial migration. This interaction might potentially control the limbal-corneal epithelial boundary.

Background Ephrin receptors (Eph) and their ligands, called ephrins, function in various disease processes. However, the expression level and prognostic value of Eph/ephrins in lung adenocarcinoma (LUAD) are still unclear. Methods The Oncomine and GEPIA databases were used to explore the differential expression of Eph/ephrins in LUAD. Kaplan–Meier plotter was selected to explore the prognostic value of Eph/ephrins. The cBioPortal database was used to analyze the genetic variation of the EFNA3 gene. Immunohistochemistry was used to analyze the expression level and clinical value of ephrin-A3 protein in clinical LUAD tissue. Weighted coexpression network analysis (WGCNA) and gene set enrichment analysis (GSEA) identified the potential regulatory mechanism of EFNA3. CCK-8 assays and colony-forming experiments were used to investigate whether EFNA3 can regulate cell proliferation ability in LUAD. Analysis of lactate, ATP, and glucose uptake levels was used to explore the effect of EFNA3 on glycolysis ability. In addition, we investigated the relationship between EFNA3 and tumor infiltrating immune cells (TIICs). Finally, the potential immunotherapy response prediction value of EFNA3 was also explored. Results In this study, we found that EFNA3 expression was significantly correlated with both overall survival (OS) and progression-free survival (PFS) in LUAD patients based on a comprehensive analysis of the Eph/Ephrin family. Next, the expression of the EFNA3 protein was increased in LUAD tissues and was designated an independent prognostic risk factor. Mechanistically, EFNA3 may be involved in nuclear division, synaptic function, and ion channel activity-related pathways. In vitro experiments confirmed the role of EFNA3 in promoting LUAD cells and showed that it could regulate glycolytic capacity. Moreover, EFNA3 was negatively associated with immunity, stromal infiltration, and several TIICs. Finally, EFNA3 was found to be positively related to multiple immunotherapy biomarkers. Conclusions In conclusion, increased EFNA3 in LUAD patients predicted worse clinical prognosis, promoted LUAD cell proliferation and glycolysis ability, and was related to immunotherapy response.

The Eph receptor tyrosine kinases and their ephrin ligands direct axon pathfinding and neuronal cell migration, as well as mediate many other cell–cell communication events. Their dysfunctional signaling has been shown to lead to various diseases, including cancer. The Ephs and ephrins both localize to the plasma membrane and, upon cell–cell contact, form extensive signaling assemblies at the contact sites. The Ephs and the ephrins are divided into A and B subclasses based on their sequence conservation and affinities for each other. The molecular details of Eph–ephrin recognition have been previously revealed and it has been documented that ephrin binding induces higher-order Eph assemblies, which are essential for full biological activity, via multiple, distinct Eph–Eph interfaces. One Eph–Eph interface type is characterized by a homotypic, head-to-tail interaction between the ligand-binding and the fibronectin domains of two adjacent Eph molecules. While the previous Eph ectodomain structural studies were focused on A class receptors, we now report the crystal structure of the full ectodomain of EphB2, revealing distinct and unique head-to-tail receptor–receptor interactions. The EphB2 structure and structure-based mutagenesis document that EphB2 uses the head-to-tail interactions as a novel autoinhibitory control mechanism for regulating downstream signaling and that these interactions can be modulated by posttranslational modifications.

During the neural circuit formation, neuronal growth cones must be guided precisely to their neuronal or muscle targets, which can be achieved by the activation of membrane-bound guidance receptors at the periphery. However, the mechanisms that regulate the temporal availability of these receptors remain largely unknown. TAR DNA binding protein-43 (TDP-43) has been proposed to bind with the mRNAs of guidance receptors, thus prompting us to investigate its role in axon guidance of the spinal lateral motor column (LMC) neurons into the limb mesenchyme. We first identified the TDP-43 expression in the LMC neurons at the stage of axons growth into the limb using in situ mRNA hybridization. The loss and gain of TDP-43 function in chick LMC neurons redirected their axon trajectory with opposite effects. In mice, a spinal motor neuron-specific TDP-43 deletion led to the misrouting of LMC axons. Further, ectopic TDP-43 expression increased EphB protein levels in LMC neurons, suggesting that TDP-43 mediates LMC pathfinding by regulating EphB expression. Finally, TDP-43 levels influenced the growth preference of LMC neurites against ephrin-B, but not Netrin-1 and Semaphorin ligands. Our results demonstrate that TDP-43 is essential for the ephrinB:EphB signaling-mediated axon trajectory selection of LMC subtypes into the limb.

The emergence of multicellularity is strongly correlated with the expansion of tyrosine kinases, a conserved family of signaling enzymes that regulates pathways essential for cell-to-cell communication. Although tyrosine kinases have been classified from several model organisms, a molecular-level understanding of tyrosine kinase evolution across all holozoans is currently lacking. Using a hierarchical sequence constraint-based classification of diverse holozoan tyrosine kinases, we construct a new phylogenetic tree that identifies two ancient clades of cytoplasmic and receptor tyrosine kinases separated by the presence of an extended insert segment in the kinase domain connecting the D and E-helices. Present in nearly all receptor tyrosine kinases, this fast-evolving insertion imparts diverse functionalities, such as post-translational modification sites and regulatory interactions. Eph and EGFR receptor tyrosine kinases are two exceptions which lack this insert, each forming an independent lineage characterized by unique functional features. We also identify common constraints shared across multiple tyrosine kinase families which warrant the designation of three new subgroups: Src module (SrcM), insulin receptor kinase-like (IRKL), and fibroblast, platelet-derived, vascular, and growth factor receptors (FPVR). Subgroup-specific constraints reflect shared autoinhibitory interactions involved in kinase conformational regulation. Conservation analyses describe how diverse tyrosine kinase signaling functions arose through the addition of family-specific motifs upon subgroup-specific features and coevolving protein domains. We propose the oldest tyrosine kinases, IRKL, SrcM, and Csk, originated from unicellular premetazoans and were coopted for complex multicellular functions. The increased frequency of oncogenic variants in more recent tyrosine kinases suggests that lineage-specific functionalities are selectively altered in human cancers.

Motor neuron disease (MND) comprises a group of fatal neurodegenerative diseases with no effective cure. As progressive motor neuron cell death is one of pathological characteristics of MND, molecules which protect these cells are attractive therapeutic targets. Accumulating evidence indicates that EphA4 activation is involved in MND pathogenesis, and inhibition of EphA4 improves functional outcomes. However, the underlying mechanism of EphA4’s function in MND is unclear. In this review, we first present results to demonstrate that EphA4 signalling acts directly on motor neurons to cause cell death. We then review the three most likely mechanisms underlying this effect.