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1.
BMC Pulm Med ; 22(1): 356, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123678

RESUMO

BACKGROUND: The aim of the study was to investigate predictive value of gene mutation for atezolizumab treatment response from OAK and POPLAR cohorts. METHODS: Several public databases were used for analyzing gene mutation type of EPHA5 and association with alterations of other genes. Survival analysis was performed for patients receiving atezolizumab from OAK and POPLAR cohorts. RESULTS: EPHA5 mutation have high frequency to harbor TP53 and KEAP1 mutations. The bTMB value has significant difference between EPHA5 mutant and wild-type cases. Patients with EPHA5 mutation got worse survival compared to those without gene mutations receiving atezolizumab (P = 0.0186). CONCLUSIONS: EPHA5 mutant NSCLC may represent a subpopulation which showed worse response after treatment of atezolizumab compared to wild-type ones.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Anticorpos Monoclonais Humanizados , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Fator 2 Relacionado a NF-E2/metabolismo , Receptor EphA5/genética , Receptor EphA5/metabolismo
2.
PeerJ ; 10: e13774, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36164608

RESUMO

Purpose: Altered DNA methylation, genetic alterations, and environmental factors are involved in tumorigenesis. As a tumor suppressor gene, abnormal EPHA5 methylation was found in gastric cancer (GC) tissues and was linked to the initiation, progression and prognosis of GC. In this study, the EPHA5 methylation level in peripheral blood leukocytes (PBLs) was detected to explore its relationship with GC risk and prognosis. Methods: A total of 366 GC cases and 374 controls were selected as the subjects of this study to collect their environmental factors, and the EPHA5 methylation status was detected through the methylation-sensitive high-resolution melting method. Logistic regression analysis was utilized to evaluate the associations among EPHA5 methylation, environmental factors and GC risk. Meanwhile, the propensity score (PS) was used to adjust the imbalance of some independent variables. Results: After PS adjustment, EPHA5 Pm (positive methylation) was more likely to increase the GC risk than EPHA5 Nm (negative methylation) (ORb = 1.827, 95% CI [1.202-2.777], P = 0.005). EPHA5 Pm had a more significant association with GC risk in the elderly (ORa = 2.785, 95% CI [1.563-4.961], P = 0.001) and H. pylori-negative groups (ORa = 2.758, 95% CI [1.369-5.555], P = 0.005). Moreover, the combined effects of EPHA5 Pm and H. pylori infection (ORc a = 3.543, 95% CI [2.233-5.621], P < 0.001), consumption of alcohol (ORc a = 2.893, 95% CI [1.844-4.539], P < 0.001), and salty food intake (ORc a = 4.018, 95% CI [2.538-6.362], P < 0.001) on increasing the GC risk were observed. In addition, no convincing association was found between EPHA5 Pm and the GC prognosis. Conclusions: EPHA5 methylation in PBLs and its combined effects with environmental risk factors are related to the GC risk.


Assuntos
Neoplasias Gástricas , Humanos , Idoso , Neoplasias Gástricas/genética , Metilação de DNA/genética , Prognóstico , Risco , Leucócitos/patologia , Receptor EphA5/genética
3.
APMIS ; 130(6): 338-345, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35332588

RESUMO

EPHA5 is a member of the Eph family of tyrosine kinase receptors, which affect carcinogenesis. The expression level of the EPHA5 receptor in a set of lung adenocarcinoma tissue samples was checked using immunohistochemistry. The relationship between EPHA5 expression and clinicopathological parameters, and epidermal growth factor receptor (EGFR) and Braf mutations were analyzed. We also checked the expression level of the EPHA5 receptor in four lung cancer cell lines. High expression of EPHA5 was found in NCI-H460 and H1299 cells, while low expression was observed in A549 and SPC-A1 cells. EPHA5 was knocked down in NCI-H460 and H1299 lung cancer cell lines using siRNAs. The proliferation, clone formation, and invasive ability were analyzed in NCI-H460 and H1299 cells with EPHA5 knockdown. The results show that the EPHA5 receptor is differently expressed in lung adenocarcinoma tissues, in which positive and negative expression of EPHA5 was found in 58.1% and 41.9% of tissues, respectively. Positive expression of EPHA5 was associated with lymph node metastasis (p = 0.002), differentiation (p = 0.020), TNM stage (p = 0.002), and EGFR mutation (p = 0.001). The proliferation, clone formation, and invasive ability were significantly decreased after EPHA5 knockdown in NCI-H460 and H1299 cells. Our data suggest that the EPHA5 receptor plays a role in tumor promotion in lung adenocarcinoma and is a potential target for lung adenocarcinoma treatment.


Assuntos
Adenocarcinoma de Pulmão , Receptores ErbB , Neoplasias Pulmonares , Receptor EphA5 , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Metástase Linfática , Mutação , Receptor EphA5/biossíntese , Receptor EphA5/genética
4.
Mol Cell Endocrinol ; 539: 111490, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655661

RESUMO

Emerging evidence suggests that the shift between osteogenic and adipogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) determines bone mass. Our study was aimed at testing whether a long noncoding RNA called zinc finger antisense 1 (ZFAS1) participates in the differentiation commitment of BMSCs during osteoporosis. We found that ZFAS1 expression was downregulated during osteogenic differentiation and upregulated during adipogenic differentiation. ZFAS1 knockdown facilitated osteogenic differentiation and suppressed adipogenic differentiation. Furthermore, ZFAS1 knockdown suppressed cell senescence and promoted autophagy. Ovariectomized mice injected with a ZFAS1 knockdown construct showed increased bone mass. Mechanismly, ZFAS1 affected the osteogenic and adipogenic differentiation of BMSCs through sponging miR-499 thereby upregulating ephrin type-A receptor 5 (EPHA5). Taken together, our results revealed that the ZFAS1-miR-499-EPHA5 axis may be important for the osteoporosis-related switch between the osteogenesis and adipogenesis of BMSCs, indicating that ZFAS1 represents a plausible therapeutic target for reversing osteoporotic bone loss.


Assuntos
Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , RNA Longo não Codificante/genética , Receptor EphA5/genética , Animais , Células Cultivadas , Senescência Celular , Feminino , Células HEK293 , Humanos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteogênese , Ovariectomia/efeitos adversos
5.
Cancer Med ; 10(18): 6227-6238, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34331411

RESUMO

BACKGROUND: Sarcomatoid hepatocellular carcinoma (HCC) is a rare and highly lethal histological subtype of HCC, with completely unknown genetic etiology and therapeutic targets. METHODS: We included 16 patients with sarcomatoid HCC receiving radical resection among 6731 cases of pathological confirmed HCC in year 2008 to 2018 in our hospital. We compared the clinical features, prognosis and cancer genome between 15 sarcomatoid HCC and propensity score-matched 75 non-sarcomatoid HCC patients. The other concurrent case was analyzed using phylogenetic tree to assess the tumor heterogeneity and evolution. RESULTS: Sarcomatoid HCC group showed larger tumor size, more advanced differentiation grade, lower tumor free survival (p = 0.038) and overall survival (p = 0.001), and sarcomatoid type was an independent risk factor for patient death. Integrating sarcomatoid subtype into AJCC staging could increase the diagnostic curve in predicting patient survival. The cancer genome spectrum showed sarcomatoid HCC group had significant higher mutation rates in CDKN2A, EPHA5, FANCM and MAP3K1. Mutations in CDKN2A significantly reduced tumor-free and overall survival in sarcomatoid HCC patients. Moreover, 46.6% sarcomatoid HCC patients had druggable mutations in cell cycle pathway genes, which were targeted by Abemaciclib, et al. We also found sarcomatoid and non-sarcomatoid lesions might originate from a common progenitor but progress differently. CONCLUSION: Our cancer genome analysis showed a specific genomic profile of sarcomatoid HCC, which were characterized by a high mutation rate in cell cycle genes particularly CDKN2A. The results indicate CDK4/6 inhibitors including abemaciclib, ribociclib and palbociclib as potential therapeutic targets and may help for therapeutic decision making.


Assuntos
Carcinoma Hepatocelular/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Neoplasias Hepáticas/genética , Fígado/patologia , Recidiva Local de Neoplasia/epidemiologia , Idoso , Aminopiridinas/uso terapêutico , Benzimidazóis/uso terapêutico , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/terapia , Quimioterapia Adjuvante , DNA Helicases/genética , Intervalo Livre de Doença , Feminino , Seguimentos , Hepatectomia , Humanos , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/terapia , MAP Quinase Quinase Quinase 1/genética , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/prevenção & controle , Prognóstico , Receptor EphA5/genética , Fatores de Risco , Carga Tumoral
6.
Brief Bioinform ; 22(6)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34109382

RESUMO

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder. Although genome-wide association studies (GWAS) identify the risk ADHD-associated variants and genes with significant P-values, they may neglect the combined effect of multiple variants with insignificant P-values. Here, we proposed a convolutional neural network (CNN) to classify 1033 individuals diagnosed with ADHD from 950 healthy controls according to their genomic data. The model takes the single nucleotide polymorphism (SNP) loci of P-values $\le{1\times 10^{-3}}$, i.e. 764 loci, as inputs, and achieved an accuracy of 0.9018, AUC of 0.9570, sensitivity of 0.8980 and specificity of 0.9055. By incorporating the saliency analysis for the deep learning network, a total of 96 candidate genes were found, of which 14 genes have been reported in previous ADHD-related studies. Furthermore, joint Gene Ontology enrichment and expression Quantitative Trait Loci analysis identified a potential risk gene for ADHD, EPHA5 with a variant of rs4860671. Overall, our CNN deep learning model exhibited a high accuracy for ADHD classification and demonstrated that the deep learning model could capture variants' combining effect with insignificant P-value, while GWAS fails. To our best knowledge, our model is the first deep learning method for the classification of ADHD with SNPs data.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Biomarcadores , Aprendizado Profundo , Predisposição Genética para Doença , Receptor EphA5/genética , Área Sob a Curva , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Biologia Computacional/métodos , Ontologia Genética , Estudo de Associação Genômica Ampla , Humanos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Curva ROC
7.
Aging (Albany NY) ; 13(1): 598-618, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33288738

RESUMO

Eph receptors constitute the largest family of RTKs, and their associations with antitumor immunity and immunotherapy are largely unknown. By integrating genomic, transcriptomic and clinical data from cohorts in public databases, we identified EPHA5 as the most common mutated gene of Eph receptors in lung adenocarcinoma (LUAD). Moreover, compared with EPHA5 wild-type (WT) patients, EPHA5-mutant (Mut) patients exhibited significantly enhanced infiltration of CD8+ T cells and M1 macrophages, reduced recruitment of immunosuppressive regulatory T cells (Tregs) into the tumor site, as well as the increased level of chemokine, interferon-gamma, inhibitory immune checkpoint signatures, tumor mutation burden (TMB) and tumor neoantigen burden (TNB). Additionally, EPHA5 mutation cooccurred with homologous recombination (HR) or mismatch repair (MMR) gene mutations. These data were validated in the LUAD cell line H1299 and a Chinese LUAD cohort. Most importantly, clinical analysis of a Memorial Sloan Kettering Cancer Center (MSKCC) immunotherapy cohort indicated that LUAD patients with EPHA5 mutations who were treated with immunotherapy had markedly prolonged survival times. Our results revealed the correlation of EPHA5 mutations with tumor immune microenvironment and predictive factors for immunotherapy, implying the potential of EPHA5 mutations as a prognostic marker for the prognosis of LUAD patients to immune checkpoint blockade therapy.


Assuntos
Adenocarcinoma de Pulmão/genética , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/genética , Linfócitos do Interstício Tumoral/imunologia , Receptor EphA5/genética , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/imunologia , Idoso , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Estudos de Coortes , Reparo de Erro de Pareamento de DNA/genética , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Reparo de DNA por Recombinação/genética , Taxa de Sobrevida , Linfócitos T Reguladores/imunologia
8.
Mol Cell Probes ; 52: 101566, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32234341

RESUMO

AIM: This study aims to evaluate the role of the EPHA5 mutation in the migration and invasion of non-small cell lung cancer (NSCLC) cells and in modulating the killing effect of natural killer (NK) cells to NSCLC cells. METHODS: EPHA5-wt (wild type) and EPHA5-mut (mutation) plasmids were constructed. EPHA5 was silenced using si-EPHA5. NSCLC cell migration and invasion were determined using Transwell assays. NK cell proliferation and apoptosis were determined using CCK-8 assay and flow cytometry, respectively. The killing effect of NK cells to NSCLC cells was also examined. RESULTS: EPHA5 mutation significantly promoted migration and invasion in NSCLC cells. Furthermore, EPHA5 mutation notably impaired the cytotoxicity of NK cells against NSCLC cells. In contrast, EPHA5-wt overexpression and EPHA5 silencing exerted the opposite effect. CONCLUSION: EPHA5 mutation impairs the NK cell-mediated cytotoxicity against NSCLC cells and promotes migration and invasion in NSCLC cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Movimento Celular/genética , Células Matadoras Naturais/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Mutação/genética , Receptor EphA5/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Morte Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Inativação Gênica , Humanos , Neoplasias Pulmonares/patologia , Invasividade Neoplásica
9.
J Gastrointest Cancer ; 51(2): 579-583, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31407253

RESUMO

PURPOSE: Gastric cancer is an aggressive disease which is the fourth prevalent malignancy in the world. Beside the genetic factors, epigenetic alterations such as promoter CpG island hyper methylation are involved in the emergence of gastric cancer. Herein, we investigated the methylation status of CDH11, EphA5, and HS3ST2 genes in patients with and without gastric adenocarcinoma for the first time. METHODS: In the study 40 paraffin-embedded tissue sections from gastric adenocarcinoma patients and 40 specimens from patients with functional dyspepsia were taken. DNA extraction was performed using a modified salting out method. Epizen DNA methylation kit was used to the bisulfite DNA conversion. The methylation status of CDH11, EphA5, and HS3ST2 genes were analyzed by methylation-specific PCR (MSP) technique. RESULTS: Among the 80 specimens, 71 DNA samples were achieved (34 gastric adenocarcinoma patients and 37 control patients). The results showed that CDH11, EphA5, and HS3ST2 genes are methylated in 28 (82.45%), 19 (55.88%), and 26 (76.47%) of 34 DNA samples from gastric adenocarcinoma patients, respectively, whereas, these genes are methylated in 7 (18.91%), 9 (24.32%) and 7 (18.91%) of 37 samples from noncancerous patients, respectively. Statistical analyses using a chi-squared test showed that there is a statistically significant difference in methylation level of CDH11, EphA5, and HS3ST2 genes between gastric cancer and uncancerous patients (p < 0.05). CONCLUSION: To the best of our knowledge, this is the first report on methylation of CDH11, EphA5, and HS3ST2 promoters' in gastric adenocarcinoma patients using MSP. Identification of novel cancer-related molecular mechanisms can be useful in detection of new treatment strategies.


Assuntos
Adenocarcinoma/genética , Caderinas/genética , Ilhas de CpG , Metilação de DNA , Receptor EphA5/genética , Neoplasias Gástricas/genética , Sulfotransferases/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Caderinas/metabolismo , Estudos de Casos e Controles , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Receptor EphA5/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Sulfotransferases/metabolismo
10.
Dev Neurobiol ; 79(3): 252-267, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30916472

RESUMO

The topographically ordered retinocollicular projection is an excellent system for studying the mechanism of axon guidance. Gradients of EphA receptors in the retina and ephrin-As in the superior colliculus (SC) pattern the anteroposterior axis of the retinocollicular map, but whether they are involved in map plasticity after injury is unknown. Partial damage to the caudal SC at birth creates a compressed, complete retinotopic map in the remaining SC without affecting visual response properties. Previously, we found that the gradient of ephrin-A expression in compressed maps is steeper than normal, suggesting an instructive role in compression. Here we measured EphA5 mRNA and protein levels after caudal SC damage in order to test the hypothesis that changes in retinal EphA5 expression occur that are complementary to the changes in collicular ephrin-A expression. We find that the nasotemporal gradient of EphA5 receptor expression steepens in the retina and overall expression levels change dynamically, especially in temporal retina, supporting the hypothesis. This change in receptor expression occurs after the change in ephrin-A ligand expression. We propose that changes in the retinal EphA5 gradient guide recovery of the retinocollicular projection from early injury. This could occur directly through the change in EphA5 expression instructing retino-SC map compression, or through ephrin-A ligand signaling instructing a change in EphA5 receptor expression that in turn signals the retinocollicular map to compress. Understanding what molecular signals direct compensation for injury is essential to developing rehabilitative strategies and maximizing the potential for recovery.


Assuntos
Plasticidade Neuronal/fisiologia , Receptor EphA5/metabolismo , Retina/metabolismo , Vias Visuais/metabolismo , Animais , Axônios/metabolismo , Cricetinae , Efrinas/genética , Modelos Animais , RNA Mensageiro/metabolismo , Receptor EphA5/genética , Células Ganglionares da Retina/metabolismo , Colículos Superiores/fisiologia
11.
Psychiatr Genet ; 29(3): 86-90, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30724859

RESUMO

About one child in 68 is affected by the autism spectrum disorder (ASD), one of the most common neurodevelopmental disorders linked to intellectual disability, especially in males, intellectual disability being diagnosable in about 60-70% of autistic individuals. The biological bases of ASD are not yet fully known, but they are generally considered multifactorial, although many genes and genomic loci have been proposed to be possibly associated with this condition. In this report, we describe the case of a 14-year-old female Italian proband affected by ASD, carrying a novel ~ 270 kb interstitial microduplication, localized at the distal portion of the 4q13.1 region. The rearrangement was inherited from a mild symptomatic father and included a large part of the single EPHA5 gene, a receptor tyrosine kinase involved in the neural development, already indicated to be linked to ASD by previous Genome Wide Association Studies. This imbalance represents, to the best of our knowledge, the smallest duplication identified to date that only impacts the EPHA5 gene. We hypothesize that the duplication of this gene may alter EPHA5 expression and that this may impact the autistic phenotype of the patient.


Assuntos
Transtorno do Espectro Autista/genética , Receptor EphA5/genética , Adolescente , Transtorno Autístico/genética , Hibridização Genômica Comparativa , Feminino , Duplicação Gênica/genética , Estudo de Associação Genômica Ampla , Genômica , Humanos , Deficiência Intelectual/genética , Itália , Fenótipo , Receptor EphA5/fisiologia
12.
FASEB J ; 33(4): 4851-4865, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30620624

RESUMO

Trastuzumab is a successful, rationally designed therapy that provides significant clinical benefit for human epidermal growth factor receptor-2 (HER2)-positive breast cancer patients. However, about half of individuals with HER2-positive breast cancer do not respond to trastuzumab treatment because of various resistance mechanisms, including but not limited to: 1) shedding of the HER2 extracellular domain, 2) steric hindrance ( e.g., MUC4 and MUC1), 3) parallel pathway activation (this is the general mechanism cited in the quote above), 4) perturbation of downstream signaling events ( e.g., PTEN loss or PIK3CA mutation), and 5) immunologic mechanisms (such as FcR polymorphisms). EPHA5, a receptor tyrosine kinase, has been demonstrated to act as an anticancer agent in several cancer cell types. In this study, deletion of EPHA5 can significantly increase the resistance of HER2-positive breast cancer patients to trastuzumab. To investigate how EPHA5 deficiency induces trastuzumab resistance, clustered regularly interspaced short palindromic repeat technology was used to create EPHA5-deficient variants of breast cancer cells. EPHA5 deficiency effectively increases breast cancer stem cell (BCSC)-like properties, including NANOG, CD133+, E-cadherin expression, and the CD44+/CD24-/low phenotype, concomitantly enhancing mammosphere-forming ability. EPHA5 deficiency also caused significant aggrandized tumor malignancy in trastuzumab-sensitive xenografts, coinciding with the up-regulation of BCSC-related markers and intracellular Notch1 and PTEN/AKT signaling pathway activation. These findings highlight that EPHA5 is a potential prognostic marker for the activity of Notch1 and better sensitivity to trastuzumab in HER2-positive breast cancer. Moreover, patients with HER2-positive breast cancers expressing high Notch1 activation and low EPHA5 expression could be the best candidates for anti-Notch1 therapy.-Li, Y., Chu, J., Feng, W., Yang, M., Zhang, Y., Zhang, Y., Qin, Y., Xu, J., Li, J., Vasilatos, S. N., Fu, Z., Huang, Y., Yin, Y. EPHA5 mediates trastuzumab resistance in HER2-positive breast cancers through regulating cancer stem cell-like properties.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Receptor EphA5/metabolismo , Trastuzumab/uso terapêutico , Antígeno AC133/metabolismo , Animais , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Proteína Homeobox Nanog/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Receptor EphA5/genética , Receptor ErbB-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Trastuzumab/farmacologia
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(12): 1272-1277, 2017 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-29237529

RESUMO

OBJECTIVE: To investigate the changes in the expression of EphA5 and its ligand ephrinA5 in the hippocampus of rats with epilepsy and their role in the pathogenesis of temporal lobe epilepsy (TLE). METHODS: A total of 240 Sprague-Dawley rats were randomly divided into control group and TLE group, with 120 rats in each group. A rat model of lithium-pilocarpine TLE was established, and then the rats were divided into subgroups at 12 and 24 hours and 7, 15, 30, and 60 days after epilepsy was induced. In-situ hybridization was used to measure the mRNA expression of ephrinA5 in the CA3 region and the dentate gyrus of the hippocampus in 9 rats; immunohistochemistry was used to measure the protein expression of EphA5 in the CA3 region and the dentate gyrus of the hippocampus in 9 rats; Neo-Timm silver staining was used to observe mossy fiber sprouting in the CA3 region of the hippocampus in 2 rats. RESULTS: In-situ hybridization showed mRNA expression of ephrinA5 in the CA3 region of the hippocampus, but this was not found in the dentate gyrus. Compared with the control group at the same time point, the TLE group had a significant reduction in the mRNA expression of ephrinA5 in the CA3 region of the hippocampus at 7 and 15 days after epilepsy was induced (P<0.05); at 30 and 60 days after epilepsy was induced, the TLE group had a gradual increase in the mRNA expression of ephrinA5 in the CA3 region of the hippocampus, and there was no significant difference between the TLE and control groups (P>0.05). Immunohistochemistry showed that EphA5 protein was expressed in the CA3 region and the dentate gyrus of the hippocampus and had a similar trend of change as ephrinA5 mRNA. Neo-Timm silver staining showed that the TLE group developed marked mossy fiber sprouting in the CA3 region of the hippocampus at 7 and 15 days after epilepsy was induced. CONCLUSIONS: Downregulation of ephrinA5 and EphA5 in the CA3 region of the hippocampus may participate in the mechanism of mossy fiber sprouting and is closely associated with the development and progression of epilepsy.


Assuntos
Efrina-A5/fisiologia , Epilepsia do Lobo Temporal/etiologia , Hipocampo/química , Receptor EphA5/fisiologia , Animais , Efrina-A5/análise , Efrina-A5/genética , Epilepsia do Lobo Temporal/metabolismo , Masculino , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptor EphA5/análise , Receptor EphA5/genética
14.
Exp Hematol ; 48: 72-78, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27988259

RESUMO

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.


Assuntos
Movimento Celular , Autorrenovação Celular , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Receptor EphA5/metabolismo , Receptor EphA7/metabolismo , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP/metabolismo , Adesão Celular/genética , Comunicação Celular , Diferenciação Celular , Movimento Celular/genética , Autorrenovação Celular/genética , Perfilação da Expressão Gênica , Humanos , Receptor EphA5/genética , Receptor EphA7/genética , Células-Tronco , Células Estromais/metabolismo
15.
Clin Cancer Res ; 23(5): 1227-1235, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27582484

RESUMO

Purpose: Neuropathy is the dose-limiting toxicity of paclitaxel and a major cause for decreased quality of life. Genetic factors have been shown to contribute to paclitaxel neuropathy susceptibility; however, the major causes for interindividual differences remain unexplained. In this study, we identified genetic markers associated with paclitaxel-induced neuropathy through massive sequencing of candidate genes.Experimental Design: We sequenced the coding region of 4 EPHA genes, 5 genes involved in paclitaxel pharmacokinetics, and 30 Charcot-Marie-Tooth genes, in 228 cancer patients with no/low neuropathy or high-grade neuropathy during paclitaxel treatment. An independent validation series included 202 paclitaxel-treated patients. Variation-/gene-based analyses were used to compare variant frequencies among neuropathy groups, and Cox regression models were used to analyze neuropathy along treatment.Results: Gene-based analysis identified EPHA6 as the gene most significantly associated with paclitaxel-induced neuropathy. Low-frequency nonsynonymous variants in EPHA6 were present exclusively in patients with high neuropathy, and all affected the ligand-binding domain of the protein. Accumulated dose analysis in the discovery series showed a significantly higher neuropathy risk for EPHA5/6/8 low-frequency nonsynonymous variant carriers [HR, 14.60; 95% confidence interval (CI), 2.33-91.62; P = 0.0042], and an independent cohort confirmed an increased neuropathy risk (HR, 2.07; 95% CI, 1.14-3.77; P = 0.017). Combining the series gave an estimated 2.5-fold higher risk of neuropathy (95% CI, 1.46-4.31; P = 9.1 × 10-4).Conclusions: This first study sequencing EPHA genes revealed that low-frequency variants in EPHA6, EPHA5, and EPHA8 contribute to the susceptibility to paclitaxel-induced neuropathy. Furthermore, EPHA's neuronal injury repair function suggests that these genes might constitute important neuropathy markers for many neurotoxic drugs. Clin Cancer Res; 23(5); 1227-35. ©2016 AACR.


Assuntos
Paclitaxel/efeitos adversos , Doenças do Sistema Nervoso Periférico/genética , Receptor EphA5/genética , Receptor EphA6/genética , Receptor EphA8/genética , Adulto , Idoso , Biomarcadores Farmacológicos/análise , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Feminino , Estudos de Associação Genética , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/administração & dosagem , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/patologia , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Qualidade de Vida
16.
J Ovarian Res ; 9(1): 83, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27887627

RESUMO

BACKGROUND: Ovarian serous carcinoma (OSC) is the most common ovarian epithelial malignancy. Disregulation of Eph/ephrin signaling has been implicated in oncogenesis and tumor progression. EphA5 receptor is one of large families of Eph tyrosine kinase receptor and is documented in the development of nervous system. Till now, there is no published data about the role of EphA5 in ovarian epithelial neoplasmas. METHODS: This study aims to investigate the expression of EphA5 protein in ovarian serous carcinoma, and its relationship to clinical pathological characteristics. Sixty-one cases of ovarian serous carcinoma, 24 cases of benign ovarian serous tumors, 42 cases of serous borderline tumors and 20 cases of normal fallopian tubes were examined using immunohistochemical staining. The relationship between EphA5 expression and pathological parameters was analyzed. Kaplan-Meier survival function was used to analyze prognosis of patients. RESULTS: Immunostaining analysis demonstrated that the EphA5 protein was highly expressed in 100% (20/20) of normal fallopian tube samples, 100% (24/24) of benign epithelial ovarian tumors, 76% (32/42) of ovarian serous borderline tumors, and 31% (19/61) of ovarian serous carcinomas. Loss of EphA5expression was associated with tumor grade (P < 0.001) and FIGO stage (P = 0.005). The survival analysis showed that patients with negative or weak expression of EphA5 protein had a poor outcome than those with positive expression (P = 0.004). CONCLUSIONS: Our results show that EphA5 may be a potential biomarker for distinguishing high-and low-grade ovarian serous carcinoma and a potential prognostic marker.


Assuntos
Biomarcadores Tumorais , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/patologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Receptor EphA5/metabolismo , Adulto , Idoso , Cistadenocarcinoma Seroso/mortalidade , Tubas Uterinas/metabolismo , Tubas Uterinas/patologia , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Ovarianas/mortalidade , Prognóstico , Receptor EphA5/genética , Adulto Jovem
17.
Restor Neurol Neurosci ; 34(6): 877-895, 2016 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-27858721

RESUMO

BACKGROUND: Cell therapy is a promising approach for Parkinson's disease (PD). Others and we have previously shown that transplantation of ventral mesencephalic fetal cells into substantia nigra (SN) in an animal model of PD enables anatomical and functional repair of the degenerated pathway. However, the molecular basis of this repair is still largely unknown. OBJECTIVE: In this work, we studied the expression of several axon guidance molecules that may be implicated in the repair of the degenerated nigrostriatal pathway. METHODS: The expression of axon guidance molecules was analyzed using qRT-PCR on five specific regions surrounding the nigrostriatal pathway (ventral mesencephalon (VM), thalamus (Thal), medial forebrain bundle (MFB), nucleus accumbens (NAcc) and caudate putamen (CPu)), one and seven days after lesion and transplantation. RESULTS: We showed that mRNA expression of specific axon guidance molecules and their receptors is modified in structures surrounding the nigrostriatal pathway, suggesting their involvement in the axon guidance of grafted neurons. Moreover, we highlight a possible new role for semaphorin 7A in this repair. CONCLUSION: Overall, our data provide a reliable basis to understand how axons of grafted neurons are able to navigate towards their targets and interact with the molecular environment in the adult brain. This should help to improve the efficiency of cell replacement approaches in PD.


Assuntos
Encéfalo/metabolismo , Regulação da Expressão Gênica/fisiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/cirurgia , Transplante de Células-Tronco/métodos , Animais , Modelos Animais de Doenças , Embrião de Mamíferos , Efrina-A2/genética , Efrina-A2/metabolismo , Efrina-A3/genética , Efrina-A3/metabolismo , Feminino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Oxidopamina/toxicidade , Doença de Parkinson/etiologia , RNA Mensageiro/metabolismo , Receptor EphA5/genética , Receptor EphA5/metabolismo , Semaforinas/genética , Semaforinas/metabolismo , Substância Negra/citologia , Simpatolíticos/toxicidade
18.
J Biol Chem ; 291(35): 18084-95, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27402841

RESUMO

Regenerative medicine holds great promise for the treatment of degenerative retinal disorders. Krüppel-like factors (KLFs) are transcription factors that have recently emerged as key tools in regenerative medicine because some of them can function as epigenetic reprogrammers in stem cell biology. Here, we show that KLF16, one of the least understood members of this family, is a POU4F2 independent transcription factor in retinal ganglion cells (RGCs) as early as embryonic day 15. When overexpressed, KLF16 inhibits RGC neurite outgrowth and enhances RGC growth cone collapse in response to exogenous ephrinA5 ligands. Ephrin/EPH signaling regulates RGC connectivity. The EphA5 promoter contains multiple GC- and GT-rich KLF-binding sites, which, as shown by ChIP-assays, bind KLF16 in vivo In electrophoretic mobility shift assays, KLF16 binds specifically to a single KLF site near the EphA5 transcription start site that is required for KLF16 transactivation. Interestingly, methylation of only six of 98 CpG dinucleotides within the EphA5 promoter blocks its transactivation by KLF16 but enables transactivation by KLF2 and KLF15. These data demonstrate a role for KLF16 in regulation of RGC neurite outgrowth and as a methylation-sensitive transcriptional regulator of EphA5 expression. Together, these data identify differential low level methylation as a novel mechanism for regulating KLF16-mediated EphA5 expression across the retina. Because of the critical role of ephrin/EPH signaling in patterning RGC connectivity, understanding the role of KLFs in regulating neurite outgrowth and Eph receptor expression will be vital for successful restoration of functional vision through optic nerve regenerative therapies.


Assuntos
Fatores de Transcrição Kruppel-Like/metabolismo , Neuritos/metabolismo , Receptor EphA5/biossíntese , Elementos de Resposta/fisiologia , Células Ganglionares da Retina/metabolismo , Transdução de Sinais/fisiologia , Ativação Transcricional/fisiologia , Animais , Metilação de DNA , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Camundongos Knockout , Receptor EphA5/genética , Células Ganglionares da Retina/citologia , Transcrição Gênica/fisiologia
19.
Neuron ; 88(5): 848-850, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26637791

RESUMO

Immature neural circuits form excessive synaptic connections that are later refined through pruning of exuberant branches. In this issue, Bornstein et al. identify a role for JNK signaling in selective axon elimination through disassembly of cell adhesion complexes.


Assuntos
Adesão Celular/genética , Sistema de Sinalização das MAP Quinases/genética , Corpos Pedunculados/citologia , Corpos Pedunculados/crescimento & desenvolvimento , Plasticidade Neuronal/genética , Receptor EphA5/genética , Animais
20.
Cancer Treat Rev ; 41(10): 935-50, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26585358

RESUMO

BACKGROUND: Taxanes, including paclitaxel and docetaxel, are indispensable for treatment of cancer. Development of toxicity frequently necessitates dose reduction or discontinuation of therapy, despite clinical response. OBJECTIVE: Pharmacogenetic studies were reviewed for identification of genetic variants possibly underlying individual susceptibility to adverse events. METHOD: We conducted a systematic search in Pubmed and Embase for pharmacogenetic reports with focus on commonly reported taxane-related gastrointestinal, hematological and neurological toxicities in adult patients with solid tumors. The findings from a total of 51 eligible studies are presented in a comprehensive way. RESULTS: Most frequently investigated single nucleotide polymorphisms (SNPs) were located in genes encoding proteins affecting pharmacokinetics, such as drug transporters and genes of the cytochrome P450 family. Inconclusive data for risk of toxicity as well as for effects on drug exposure were reported on variants in ABCB1, CYP3A4, CYP3A5 and, for paclitaxel, CYP2C8. Interest is also dedicated towards genes involved in pharmacodynamics, such as detoxification of reactive oxygen species, DNA repair, neuronal processes and microtubule function. Recent studies include variants in TUBB2A, EPHA5 and EPHA6 for a possible association with neurotoxicity. Variations in methodological approach, sample size, study design, treatment schedule and end-point of toxicity affect consistency of results. CONCLUSION: This review illustrates the complexity to well design pharmacogenetic studies for validation of SNPs that may clarify differences in taxane-induced toxicities among individuals. Novel genes encoding cellular targets of taxanes deserve further analysis by means of robust patient cohorts and definition of objective end-points.


Assuntos
Antineoplásicos/efeitos adversos , Gastroenteropatias/induzido quimicamente , Doenças Hematológicas/induzido quimicamente , Síndromes Neurotóxicas/etiologia , Paclitaxel/efeitos adversos , Taxoides/efeitos adversos , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Citocromo P-450 CYP2C8/genética , Citocromo P-450 CYP3A/genética , Docetaxel , Gastroenteropatias/genética , Doenças Hematológicas/genética , Humanos , Síndromes Neurotóxicas/genética , Farmacogenética , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Receptor EphA5/genética , Receptor EphA6/genética , Tubulina (Proteína)/genética
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