FRK通过FAK信号通路抑制脑胶质瘤细胞迁移与侵袭作用的研究

目的研究酪氨酸相关激酶(fyn-related kinase,FRK)是否通过粘着斑激酶(focal adhesion kinase,FAK)信号通路抑制脑胶质瘤细胞的迁移和侵袭。方法采用Western blot(WB)检测FRK质粒的转染效果,细胞划痕和Transwell侵袭实验检测过表达FRK及下调FAK对胶质瘤U251细胞迁移和侵袭能力的影响;WB检测过表达FRK对FAK、P-FAK蛋白水平的影响以及下调FAK对FRK蛋白水平的影响。结果FRK质粒转染成功。过表达FRK后胶质瘤U251细胞的迁移与侵袭能力下降。FAK siRNA干扰效率达到70%,下调FAK后胶质瘤U251细胞的迁移与侵袭能力下降。过表达FRK后P-FAK的蛋白水平明显下降,而FAK蛋白水平无明显变化,下调FAK对FRK的蛋白水平无明显影响。结论 FRK可能通过抑制FAK的磷酸化来调控胶质瘤的侵袭与迁移。     

Slit2/Robo1 signaling in glioma migration and invasion

Slit2/Robo1 is a conserved ligand-receptor system, which greatly affects the distribution, migration, axon guidance and branching of neuron cells. Slit2 and its transmembrane receptor Robo1 have different distribution patterns in gliomas. The expression of Slit2 is at very low levels in pilocytic astrocytoma, fibrillary astrocytoma and glioblastoma, while Robo1 is highly expressed in different grades of gliomas at both mRNA and protein levels. Acquisition of insidious invasiveness by malignant glioma cells involves multiple genetic alterations in signaling pathways. Although the specific mechanisms of tumor-suppressive effect of Slit2/Robo1 have not been elucidated, it has been proved that Slit2/Robo1 signaling inhibits glioma cell migration and invasion by inactivation of Cdc42-GTP. With the research development on the molecular mechanisms of Slit2/Robo1 signaling in glioma invasion and migration, Slit2/Robo1 signaling may become a potential target for glioma prevention and treatment.     

FRK通过N-cadherin／E-cadherin胶质瘤细胞侵袭和迁移途径抑制

目的探讨抑癌基因FRK（Fyn-relatedkinase）影响胶质瘤细胞侵袭和迁移的机制。方法将真核表达质粒pcDNA3．0-FRK和对照质粒pcDNA3．0转入人胶质瘤U251细胞中,westernblot技术检测FRK／N．cadherin／E—cadherin蛋白表达,细胞划痕试验检测细胞迁移能力,Transwell侵袭实验检测细胞侵袭能力。结果与对照组比较,转染pcl）NA3．0-FRK质粒24h后U251细胞侵袭能力下降47％、迁移能力下降64％,差异均有统计学意义（P〈0．01）;转染pcDNA3．0-FRK可以明显增加N—cadherin／E—cadherin的表达。结论FRK可以通过增加N．cadherin／E—cadherin的表达,进而抑制胶质瘤细胞侵袭和迁移能力。     

Silencing of OTUB1 inhibits migration of human glioma cells in vitro

OTU domain‐containing ubiquitin aldehyde‐binding protein 1 (OTUB1) protein, a deubiquitinating enzyme (DUB) which belongs to the ovarian tumor (OTU) family, was reported to be associated with the development of various malignancies. However, the potential function of OTUB1 in human gliomas was still unclear. In this study, we sought to investigate the function of OTUB1 in the pathological process of gliomas and analyze its related clinical significance. Western blot and immunohistochemistry analyses demonstrated that OTUB1 was overexpressed in glioma tissues, and statistical analysis suggested the expression level of OTUB1 was significantly correlated with the WHO grades of human gliomas (P < 0.05). Moreover, Kaplan–Meier curve also indicated that high expression of OTUB1 was correlated with a poor prognosis. In vitro, silencing OTUB1 retarded the migration ability of glioma cells. Knockdown of OTUB1 increases epithelial‐mesenchymal transition‐related protein E‐cadherin expression, but decreases simultaneously the expression of vimentin and snail. Furthermore, down‐regulated expression of OTUB1 also resulted in decreased expression of some extracellular matrix degradation‐related proteins, such as matrix metallopeptidase (MMP)2 and MMP9. All results suggested that OTUB1 was a valuable marker in the pathogenesis of human gliomas and could be used as a novel biomarker for glioma therapy in the future.     

L1 expressed by glioma cells promotes adhesion but not migration

L1 is an adhesion molecule of the immunoglobulin superfamily expressed by several types of cancer, including gliomas. It has been shown that L1 can act as chemoattractant to glioma cells, while the effects of L1 expressed by glioma cells themselves are unknown to date. We established a C6 rat glioma clone, conditionally expressing murine L1 under control of a tetracycline responsive promoter. In vitro experiments revealed increased adhesion on matrigel as well as increased intercellular adhesion in the presence of L1, whereas no L1-dependent effects on proliferation or migration on either matrigel or myelin were observed. In vivo experiments using transplantation into nude mouse striatum, where L1 expression by glioma cells was regulated by tetracycline via drinking water, did not show effects of L1 on tumor size or brain invasion. Our data suggest that L1 expressed on the surface of glioma cells increases cell-matrix and intercellular adhesion, but has no apparent effects on proliferation and invasion.     

Hax-1对胶质瘤细胞增殖、迁移和侵袭的作用

目的 探讨造血干细胞特异性相关结合蛋白-1(Hax-1)对胶质瘤细胞增殖、迁移和侵袭的影响.方法 选择2018年9月至2019年6月手术切除并得到术后病理证实的胶质瘤组织35例和颅脑损伤内减压术切除的正常脑组织35例,采用qRT-PCR检测Hax-1 mRNA水平;同时检测胶质瘤细胞系(U87、A172、T98及U34...     

上皮间质转化与胶质瘤侵袭迁移的研究进展

胶质瘤是一种恶性程度高、浸润性生长的颅内原发性肿瘤。肿瘤的侵袭和转移是导致患者预后差的主要原因。上皮细胞-间质细胞转换(EMT)是胶质瘤细胞获得高度迁移和侵入表型特征的关键过程。EMT是一个进化上保守的细胞发育程序,和致癌效应密切相关。该文就EMT与胶质瘤侵袭迁移相关作用机制和靶向治疗进行综述,为胶质瘤的诊疗研究提供理论依据。     

Intersectin1‐s,A multidomain adapter protein,Is essential for malignant glioma proliferation

Glioblastomas, the most aggressive form of primary brain tumors with a tendency to invade surrounding healthy brain tissues, remains an incurable disease. Intersectin (ITSN) is a multidomain adapter protein implicated in endocytosis, exocytosis, and multiple signaling pathways. Prior research of ours has shown intersectin1‐S (ITSN1‐S) is critical for the migration and invasion of glioma cells by regulating several key proteins. In this study, we established ITSN1‐S expression patterns in human tumor tissues. We discovered that ITSN1‐S expression was positively correlated with histological grade of gliomas and with poor patient prognosis. We also found that the expression of ITSN1‐S protein was essential to glioblastoma cell proliferation. Furthermore, through a series of expression constructs encoding different ITSN1‐S domains, we identified the critical roles of ITSN1‐S SH3 domains in the regulation of cell proliferation. This study also demonstrates evidence suggesting that the regulation of ITSN1‐S on glioblastoma cells proliferation is through the Raf/MEK/ERK pathway. In conclusion, this study suggests critical roles of ITSN1‐S in malignant glioma proliferation, indicating a potential usage of ITSN1‐S in the therapeutic intervention as a novel molecular target. GLIA 2015;63:1595–1605     

Leptin induces migration and invasion of glioma cells through MMP-13 production

Leptin, the product of the obese gene, plays an important role in the regulation of body weight by coordinating metabolism, feeding behavior, energy balance, and neuroendocrine responses. However, regulation of leptin gene expression in the central nervous system is different from that in the adipocytes. In addition, leptin has been found in many tumor cell lines and has been shown to have mitogenic and angiogenic activity in a number of cell types. Glioma is the most common primary adult brain tumor with poor prognosis because of the spreading of tumor cell to the other regions of brain easily. Here we found that malignant C6 glioma cells expressed more leptin and leptin receptors than nonmalignant astrocytes. Furthermore, it was found that exogenous application of leptin enhanced the migration and invasion of C6 glioma cells. In addition, we found that the expression of matrix metalloproteinase-13 (MMP-13) but not of MMP-2 and MMP-9 was increased in response to leptin stimulation. The leptin-induced increase of cell migration and invasion was antagonized by MMP-13 neutralizing antibody or silencing MMP-13. The up-regulation of MMP-13 induced by leptin was mainly through p38 MAP kinase and NF-kappaB pathway. In addition, migration-prone sublines demonstrate that cells with increasing migration ability had more expression of MMP-13 and leptin. Taken together, these results indicate that leptin enhanced migration and invasion of C6 glioma cells through the increase of MMP-13 production.     

Knockdown of annexin 2 decreases migration of human glioma cells in vitro

Diffuse invasion of brain tissue is a major reason for the poor prognosis of patients with glioblastoma. Annexin 2, a member of the large annexin family of Ca2+ and membrane-binding proteins, is expressed at high protein levels in human gliomas and has been proposed as a marker of glioma malignancy, while its functional role in these tumours is unknown so far. The ability of annexin 2 to interact with the actin cytoskeleton, as well as its potential to bind invasion-associated proteases, suggests that it could participate in invasion-associated processes in human gliomas. Therefore, we analysed here functional consequences of RNA interference-mediated silencing of annexin 2 in U87MG and U373MG human glioma cell lines. While no impact of annexin 2 downregulation on proliferation and adhesion was observed, our analyses revealed that migration of U87MG and U373MG cells was significantly inhibited following annexin 2 depletion. This effect was not related to a compensatory increase of the related annexins 1 or 6. Our findings identify annexin 2 as a potential candidate involved in glioma invasion and support the potential of RNA interference as powerful tool in the decryption of glioma invasion mechanisms.     

Role of high molecular weight extracellular matrix proteins in glioma cell migration

Malignant human gliomas are characterized by an uncontrolled cell proliferation and infiltrative growth within the brain. Complete surgical removal is difficult due to disseminated tumour cells, and the fundamental mechanisms responsible for this spread are poorly understood. An extensive tumour cell movement along blood vessels is frequently observed and this may be due to specific interactions between tumour cell surface receptors and specific extracellular matrix (ECM) components present in conjunction with vascular elements. In order to investigate the influence of ECM on glioma cell migration, three different human glioma cell lines (U-373 MG, A-172 MG and HF-66) were exposed to known ECM components of the basement membrane (laminin, fibronectin and collagen type IV). Cell migration from multicellular spheroids was studied, using a custom-made medium which was prepared by removing the high molecular weight protein fraction (>100 kDa) from newborn calf serum by ultrafiltration. To this medium, the specific ECM components were added. For two of the cell lines (A-172 MG and U-373 MG), laminin was the most potent stimulator of glioma cell migration; the effect of laminin exceeded that evoked by ordinary serum-supplemented medium. For the HF-66 cell line, fibronectin was the most potent stimulator of migration. Western blot analysis showed that the A-172 MG and HF-66 cell lines expressed low amounts of laminin compared with U-373 MG, which showed extensive intrinsic synthesis of this ligand. U-373 MG was the only cell line that migrated in pure filtered medium. The cells stimulated by fibronectin expressed a different morphology from those stimulated by laminin suggesting that specific ECM-receptor binding may activate different cytoskeletal components within the cells. Furthermore, it was shown that there was no difference in the amount of protein synthesis between cells grown in filtered medium and in filtered medium supplemented with different ECM components. This suggests that ECM-induced cell migration is not dependent on a high level of protein synthesis. It is also shown that α3 integrin, which is a receptor-subunit for laminin, fibronectin and collagen type IV, was highly expressed in all cell lines. This study indicates that glioma cells need serum proteins with a molecular weight >100 kDa to migrate in vitro, and that laminin and fibronectin play an important role in this process.     

上调LRIG1对胶质瘤U251细胞侵袭、迁移的影响

目的 探讨上调LRIG1表达对胶质瘤U251细胞侵袭及迁移的影响.方法 体外培养U251细胞,应用Lipofectami-neTM2000试剂盒将质粒pLRIG1-GFP(pLRIG1-GFP组)及其空载pEGFP-N1质粒(pEGFP-N1组)转染U251细胞,G418挑选具有抗性的细胞并扩增,以供进一步实验.另选择...     

胶质瘤组织miR-3653的表达及miR-3653对胶质瘤TG905细胞侵袭、迁移的影响

目的 探讨胶质瘤组织miR-3653表达变化及miR-3653对人胶质瘤TG905细胞侵袭和迁移的影响及其分子机制.方法 收集2017年1月至2019年3月手术切除胶质瘤组织和瘤旁脑组织各25例.体外培养TG905细胞,过表达组转染MiR-3653 mimic质粒,过表达对照组转染NC-MiR-3653 mimic质粒...     

钙蛋白酶-1在胶质瘤组织中的表达及其对U87细胞侵袭和迁移的影响

目的 探讨钙蛋白酶-1在人脑胶质瘤组织中的表达及其对U87胶质瘤细胞侵袭和迁移的影响。方法 收集2015年1月至2018年3月手术切除的胶质瘤组织和瘤旁正常脑组织各57例。体外培养U87细胞,将阴性对照小干扰RNA（NC组）和钙蛋白酶-1小干扰RNA（钙蛋白酶-1组）转染至人胶质瘤细胞株U87,以未转染的U87细胞为对照组。采用RT-PCR和免疫印迹法检测mRNA和蛋白表达水平,Transwell实验检测U87细胞侵袭能力,划痕实验评估U87细胞迁移能力。结果 胶质瘤组织钙蛋白酶-1 mRNA和蛋白表达水平均显著高于瘤旁正常脑组织（P<0.05）。钙蛋白酶-1组U87细胞钙蛋白酶-1 mRNA和蛋白表达水平、细胞侵袭数目、细胞迁移率以及转化生长因子-β、基质金属蛋白酶（MMP）-2和MMP-9 mRNA表达水平均明显低于对照组和NC组（P<0.05）,而对照组和NC组均无统计学差异（P>0.05）。结论 钙蛋白酶-1在人脑胶质瘤中表达升高,而抑制钙蛋白酶-1表达可能通过影响上皮间质转化,抑制胶质瘤细胞侵袭和迁移。     

microRNA-328 is a favorable prognostic marker in human glioma via suppressing invasive and proliferative phenotypes of malignant cells

Objective: microRNA (miR)-328 has been reported to be implicated into tumorigenesis and tumor progression in human gliomas. However, there were controversial study results in relation to its expression pattern as well as functions in this disease. The aim of the current study was to determine the clinical significance of miR-328 expression in patients with gliomas and its effect in tumor cell malignant phenotypes. Methods: Quantitative real-time PCR was performed to detect the expression levels of miR-328 in 116 glioma and 15 non-neoplastic brain tissues. Then, the correlations of miR-328 expression with selected clinicopathologic parameters and clinical outcome of glioma patients were statistically evaluated. Moreover, CCK-8 and transwell assays were performed to investigate the functions of miR-328 in cell proliferation, invasion and migration, respectively. Results: Compared to non-neoplastic brain tissues, the expression levels of miR-328 were significantly downregulated in glioma tissues (p < 0.001). In addition, miR-328 downregulation was significantly associated with WHO grade (p < 0.001) and Karnofsky performance status score (p = 0.02). Moreover, glioma patients with low miR-328 expression exhibited markedly shorter overall survival than those with high expression (p < 0.001). Furthermore, functional assays in vitro system demonstrated that enforced expression of miR-328 could notably attenuate cell proliferation, invasion and migration of two glioma cell lines, including U251 and U87. Conclusions: Our data offer the convincing evidence that loss of miR-328 expression may stimulate advanced tumor progression and adverse outcome via promoting cellular proliferation and invasion. We propose a tumor suppressive role of miR-328 and its potential therapeutic value in human glioma.     

The role of integrin receptors in aspects of glioma invasion in vitro

Integrins are heterodimers consisting of non-covalently associated alpha and beta subunits. They mediate adherence of normal and tumour cells to the extracellular matrix, a property which is essential for migration of neoplastic astrocytes as they invade into the normal brain parenchyma. Flow cytometry and immunocytochemical analysis of cultured cells derived from 10 gliomas (1 pilocytic astrocytoma, 1 astrocytoma, 1 oligoastrocytoma, 1 anaplastic oligoastrocytoma, 4 anaplastic astrocytomas and 2 glioblastoma multiforme) revealed that the β₁ integrin subunit was generally expressed more strongly than α₄ or α_v integrin subunits. Subsequent studies with function-blocking antibodies against the β₁ subunit inhibited adhesion, motility and invasion of the gliomas in vitro, to varying degrees, on all extracellular matrix substrates investigated (laminin, collagen type IV, fibronectin and vitronectin), the inhibition by β₁ subunit was greatest on collagen type IV. These studies therefore substantiate the case for a role of the β₁ integrin subunit in neoplastic glial cell invasion of the brain.     

FHOD1 is upregulated in glioma cells and attenuates ferroptosis of glioma cells by targeting HSPB1 signaling

Background

As a new type of regulatory cell death, ferroptosis has been proven to be involved in cancer pathogenesis and therapeutic response. However, the detailed roles of ferroptosis or ferroptosis-associated genes in glioma remain to be clarified.

Methods

Here, we performed the TMT/iTRAQ-Based Quantitative Proteomic Approach to identify the differentially expressed proteins between glioma specimens and adjacent tissues. Kaplan–Meier survival was used to estimate the survival values. We also explored the regulatory roles of abnormally expressed formin homology 2 domain-containing protein 1 (FHOD1) in glioma ferroptosis sensitivity.

Results

In our study, FHOD1 was identified to be the most significantly upregulated protein in glioma tissues. Multiple glioma datasets revealed that the glioma patients with low FHOD1 expression displayed favorable survival time. Functional analysis proved that the knockdown of FHOD1 inhibited cell growth and improved the cellular sensitivity to ferroptosis in glioma cells T98G and U251. Mechanically, we found the up-regulation and hypomethylation of HSPB1, a negative regulator of ferroptosis, in glioma tissues. FHOD1 knockdown could enhance the ferroptosis sensitivity of glioma cells via up-regulating the methylated heat-shock protein B (HSPB1). Overexpression of HSPB1 significantly reversed FHOD1 knockdown-mediated ferroptosis.

Conclusions

In summary, this study demonstrated that the FHOD1-HSPB1 axis exerts marked regulatory effects on ferroptosis, and might affect the prognosis and therapeutic response in glioma.     

白头翁皂苷D对胶质瘤细胞转移和凋亡的影响及机制研究

目的 探究白头翁皂苷D （PSD）对胶质瘤细胞U251MG转移和凋亡的影响及可能机制。方法 采用CCK-8试剂盒检测正常星形胶质细胞和U251MG细胞活力;选用0.0、1.0、2.0及5.0 μmol/L PSD处理U251MG,将细胞分为4组：PSD 0.0 μmol/L组、PSD 1.0 μmol/L组、PSD 2.0 μmol/L组和PSD 5.0 μmol/L组。划痕实验检测细胞迁移能力;Transwell检测细胞侵袭能力;Hoechst 33258染色检测细胞凋亡状况;RT-PCR检测mRNA表达水平;蛋白免疫印迹检测基质金属蛋白酶-2（MMP-2）、尿激酶型纤溶酶原激活物（uPA）、纤溶酶原激活物抑制剂-1（PAI-1）、血管内皮生长因子（VEGF）、cleaved caspase-3、cleaved caspase-9、肝细胞生长因子受体（c-MET）蛋白表达水平。结果 PSD抑制正常星形胶质细胞和胶质瘤细胞U251MG细胞活力。与PSD 0.0 μmol/L组相比较,PSD 1.0、2.0及5.0 μmol/L组细胞迁移率降低（P<0.01）,MMP-2、uPA、PAI-1、VEGF、c-MET蛋白水平降低（P<0.05）,PSD 1.0 μmol/L组细胞侵袭数降低（P<0.05）,PSD 2.0及5.0 μmol/L组细胞侵袭数降低（P<0.01）,细胞凋亡率升高（P<0.05）,cleaved caspase-3、cleaved caspase-9蛋白水平升高（P<0.05）。结论 PSD通过靶向c-MET抑制胶质瘤细胞U251MG迁移和侵袭,并诱导细胞凋亡。     

肿瘤血管内皮细胞对胶质瘤细胞侵袭力的影响

目的 探讨胶质瘤血管内皮细胞(GVEC)在胶质瘤瘤细胞浸润过程中的作用.方法 通过免疫磁珠分离肿瘤血管内皮细胞,Tanswell 研究内皮细胞对胶质瘤细胞的迁徙和侵袭能力.结果 将内皮细胞与胶质瘤细胞共同培养后能显著增加其迁徙和侵袭能力,并能增加MMP-2,9 蛋白的表达.结论 血管内皮细胞与胶质瘤浸润的过程密切相关,通过增加MMP-2,9 蛋白的表达提高浸润的能力.