Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

RASSF1A is a major tumor suppressor gene located at 3p21.3. We investigated the role of aberrant promoter region hypermethylation of RASSF1A in a large series of adult gliomas. RASSF1A was frequently methylated in both primary tumors (36/63; 57%) and tumor cell lines (7/7; 100%). Hypermethylation of RASSF1A in glioma cell lines correlated with loss of expression and treatment with a demethylating agent-reactivated RASSF1A gene expression. Furthermore, re-expression of RASSF1A suppressed the growth of glioma cell line H4 in vitro. Next, we investigated whether other members of the RASSF gene family were also inactivated by methylation. NORE1B and RASSF3 were not methylated in gliomas, while NORE1A and RASSF5/AD037 demonstrated methylation in glioma cell lines but not in primary tumors. We then investigated the methylation status of three other candidate 3p21.3 tumor suppressor genes. CACNA2D2 and SEMA3B were not frequently methylated, but the BLU gene located just centromeric to RASSF1 was frequently methylated in glioma cell lines (7/7) and in 80% (35/44) of glioma tumors. In these tumor cell lines, BLU expression was restored after treatment with a demethylating agent. Loss of BLU gene expression in glioma tumors correlated with BLU methylation. There was no association between RASSF1A and BLU methylation. RASSF1A methylation increased with tumor grade, while BLU methylation was seen at similar frequencies in all grades. Our data implicate RASSF1A and BLU promoter methylation in the pathogenesis of adult gliomas, while other RASSF family members and CACNA2D2 and SEMA3B appear to have only minor roles. In addition, RASSF1A and BLU methylation appear to be independent and specific events and not due to region-wide changes in DNA methylation.
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PMID:Frequent epigenetic inactivation of RASSF1A and BLU genes located within the critical 3p21.3 region in gliomas. 1474 9

Gliomas are characterised by local infiltration, migration of tumour cells across long distances and sustained angiogenesis; therefore, proteins involved in these processes are most likely important. Such candidates are semaphorins involved in axon guidance and cell migration. In addition, semaphorins regulate tumour progression and angiogenesis. For cell signalling, class-4 semaphorins bind directly to plexins, whereas class-3 semaphorins require additional neuropilin (NRP) receptors that also bind VEGF(165). The anti-angiogenic activity of class-3 semaphorins can be explained by competition with VEGF(165) for NRP binding. In this study, we analysed the expressions of seven semaphorins of class-3, SEMA4D, VEGF and the NRP1 and NRP2 receptors in 38 adult glial tumours. In these tumours, SEMA3B, SEMA3G and NRP2 expressions were related to prolonged survival. In addition, SEMA3D expression was reduced in high-grade as compared with low-grade gliomas. In contrast, VEGF correlated with higher grade and poor survival. Thus, our data suggest a function for a subset of class-3 semaphorins as inhibitors of tumour progression, and the prognostic value of the VEGF/SEMA3 balance in adult gliomas. Moreover, in multivariate analysis, SEMA3G was found to be the only significant prognostic marker.
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PMID:Semaphorin, neuropilin and VEGF expression in glial tumours: SEMA3G, a prognostic marker? 1878 Nov 79

The aim of the current study was to explore mechanisms of SEMA3B gene expression and its clinical significance in glioma, and provide a theoretical foundation for investigating individualized treatment in glioma. Paraffin-embedded tissues from 43 patients with a confirmed clinical diagnosis of glioma following neurosurgery at the First Affiliated Hospital of Zhengzhou University from December 2013 to April 2014 were selected randomly. An additional three normal brain tissues were obtained following encephalic decompression excision due to acute craniocerebral injury in the same period, which were used as the control group. Immunohistochemical staining for vascular endothelial growth factor was performed on the glioma tissues from the 43 patients. Genomic DNA was extracted for bisulfate conversion and sequencing. SEMA3B was fully expressed in the three normal brain tissues, and incompletely expressed in the 43 glioma tissues, with a lack of expression in 48.8% (21/43) of samples. Moreover, 58% of high-grade gliomas (grade III and IV) lacked SEMA3B expression, which was significantly more than those that lacked expression (20%) in low-grade gliomas (grade I and II), indicating that, as the clinical pathological grade increased, SEMA3B expression decreased. The occurrence and development of malignant tumors is a product of multiple genes and other factors. Here, we provide theoretical basis for glioma development and prognosis involving DNA-methylation driven silencing of SEMA3B, and thus, SEMA3B is a potential target for directed treatments against glioma.
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PMID:Mechanism of SEMA3B gene silencing and clinical significance in glioma. 2705 Sep 58

In the present study, a series of studies were conducted to explore the function of miR-374b in glioma and the regulatory relationship among miR-374b, GATA3 and SEMA3B. In the present study, miR-374b mimics and inhibitors were employed to regulate miR-374b expression. Besides, qRT-PCR assay was used for detecting the expression level of miR-374b, GATA3 and SEMAB mRNAs. To verify the targeting relationship between miR-374b and GATA3, dual luciferase analysis was utilized. Moreover, chromatin immunoprecipitationn (ChIP) assay was performed for identify the correlation of GATA3 with SEMA3B. Furthermore, si1-GATA3, si2-GATA3 and pc-GATA3 were used to regulate GATA3 expression, and pc-SEMA3B was taken advantage for dysregulating SEMA3B. For assessing the significance of miR374b alone or co-operated with GATA3 or SEMA3B in cell viability, migration and apoptosis, CCK-8, transwell and FCM assay were performed, respectively. We found that overexpression of miR-374b, which was identified in glioma tissues and cell lines, U251, LN-299 and GOS-3, promoting cell migration and enhancing cell viability but inhibiting cell apoptosis were suggested in this research. Besides, GATA3 contributed to increase in cell viability and migration and decrease in cell apoptosis targeted by miR-374b as evidenced by dual luciferase assay. Moreover, GATA3 binding to the promoter of SEMA3B involved in regulating SEMA3B was revealed. Further, a series of studies demonstrated that miR-374b targeting GATA3 regulating SMEA3B resulted in elevation in cell viability and migration but suppression in cell apoptosis. But the promotion effects of miR-374 in glioma process were reversed by co-transfecting pc-GATA3 or pc-SEMA3B. In conclusion, miR-374b promotes glioma process in vitro through suppressing SEMA3B via targeting GATA3. The result of this study provides an important clue to the optimal treatment schedule for glioblastoma.
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PMID:MiR-374b targets GATA3 to promote progression and development of glioblastoma via regulating SEMA3B. 3086 92