Analyzing network formation during brain tumour initiation

分析脑肿瘤发生过程中的网络形成

• 批准号: 2443926
• 金额: --
• 依托单位: University of Edinburgh
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2443926
• 关键词: Analyzing; network; formation; during; brain

High grade gliomas (HGGs) represent a complex and devastating disease and are posing an unmet clinical need. These tumours resist multi-modal therapies and survival times are only 14 months on average1. Recent studies show that glioma cells make neural network-likeconnections with one another, and with host tissue2-4.Tumour cells have been shown to be connected by long cellular processes called tumour microtubes. Tumour microtubes (TM) are crucial for the invasion and proliferation of glioma cells and connect single tumour cells to a functional communicating network, greatly enhancing its growth and drug-resistance.The Sieger lab have developed a novel model to analyse glioma initiation stages in the larval zebrafish and were able to show that brain tumour initiating cells hijack mechanisms which are usually employed to direct microglial processes towards highly active neurons and injuries in the brain5. This aberrant role of microglia results in the active promotion of proliferation of early tumour cells. Interestingly, it is now clear that microglia play several roles in the formation of neural networks in the healthy brain, e.g. by promoting axonal growth, synapse formation and circuit function6-9. Measurements of Ca2+ transients revealed active signalling activity in these early tumour cells, implying functionality of these early networks. Importantly, we found that interfering with microglia activity resulted in impaired tumour microtube outgrowth as well as decreased Ca2+ signalling within the network.My project will focus on the cellular networks built during HGGs formation. The principal long-term aims are:1. To visually identify and characterise brain TMs in vivo using state-of-the-art microscopy;2. To delineate the tumoral calcium networks established during the first phases of tumour formation, using calcium live imaging;3. To investigate the role of microglia in the calcium signalling patterns of TM-positive fish, and their influence on tumour cells transcriptome.The tumour initiation model I will use is based on overexpression of human oncogene AKT1 in zebrafish larvae, as this has previously shown to lead to glioma formation. The oncogene expression is linked to fluorescent labelling to allow for easy identification in vivo. Calcium imaging will be based on an already established mutagenic zebrafish line expressing the beta-actin:GCamp6f calcium reporter.References:1. Wen, P. Y. & Kesari, S. Malignant gliomas in adults. N. Engl. J. Med. 359, 492-507 (2008). 2. Osswald, M. et al. Brain tumour cells interconnect to a functional and resistant network. Nature 528, 93-98 (2015). 3. Venkatesh, H. S. et al. Electrical and synaptic integration of glioma into neural circuits. Nature 573, 1-27 (2019). 4. Venkataramani, V. et al. Glutamatergic synaptic input to glioma cells drives brain tumour progression. Nature 3, 147 (2019). 5. Chia, K., Keatinge, M., Mazzolini, J. & Sieger, D. Brain tumours repurpose endogenous neuron to microglia signalling mechanisms to promote their own proliferation. Elife 8, 19 (2019). 6. Miyamoto, A. et al. Microglia contact induces synapse formation in developing somatosensory cortex. Nature Communications 1-12 (2019). 7. Cunningham, C. L., Martinez-Cerdeno, V. & Noctor, S. C. Microglia Regulate the Number of Neural Precursor Cells in the Developing Cerebral Cortex. Journal of Neuroscience 33, 4216-4233 (2013). 8. Ueno, M. & Yamashita, T. Bidirectional tuning of microglia in the developing brain: from neurogenesis to neural circuit formation. Current Opinion in Neurobiology 27, 8- 15 (2014). 9. Mosser, C.-A., Baptista, S., Arnoux, I. & Audinat, E. Microglia in CNS development: Shaping the brain for the future. Progress in Neurobiology 149-150, 1-20 (2017).

高级别神经胶质瘤（HGG）是一种复杂的破坏性疾病，临床需求尚未得到满足。这些肿瘤抵抗多模式治疗，平均存活时间仅为14个月1。最近的研究表明，胶质瘤细胞之间以及与宿主组织之间形成神经网络样连接2 - 4。肿瘤细胞被证明是通过称为肿瘤微管的长细胞过程连接的。肿瘤微管（TM）对于胶质瘤细胞的侵袭和增殖至关重要，并将单个肿瘤细胞连接到功能性通信网络，大大促进了它的生长和药物-Sieger实验室已经开发出一种新的模型来分析斑马鱼幼虫中的神经胶质瘤起始阶段，并且能够表明脑肿瘤起始细胞劫持通常用于将小胶质细胞过程导向高度活跃的细胞的机制。神经元和脑损伤5.小胶质细胞的这种异常作用导致早期肿瘤细胞增殖的积极促进。有趣的是，现在很清楚，小胶质细胞在健康大脑中神经网络的形成中起着几种作用，例如通过促进轴突生长，突触形成和回路功能6 -9。Ca 2+瞬变的测量揭示了这些早期肿瘤细胞中活跃的信号传导活性，这意味着这些早期网络的功能。重要的是，我们发现干扰小胶质细胞活性会导致肿瘤微管生长受损以及网络内Ca 2+信号传导减少。我的项目将重点关注HGG形成期间构建的细胞网络。主要的长期目标是：1。使用最先进的显微镜在体内视觉上识别和定位脑TM;2.利用钙离子活体显像描绘肿瘤形成初期建立的钙离子网络;为了研究小胶质细胞在TM阳性鱼的钙信号模式中的作用，以及它们对肿瘤细胞transcriptome.The肿瘤启动模型的影响，我将使用的是基于人类癌基因AKT 1在斑马鱼幼虫中的过表达，因为这以前已经证明会导致胶质瘤的形成。癌基因表达与荧光标记相关联，以便于体内识别。钙成像将基于已经建立的表达β-肌动蛋白：GCamp 6 f钙报告基因的诱变斑马鱼系。温，P. Y。& Kesari，S.成人恶性胶质瘤。N. Engl. 359，492-507（2008）。2. Osswald，M.脑肿瘤细胞与功能性和抗性网络互连。Nature 528，93-98（2015）. 3. Venkatesh，H. S.神经胶质瘤进入神经回路的电和突触整合。Nature 573，1-27（2019）. 4. Venkataramani，V. et al. Glutamatergic synaptic input to glioma cells drives brain tumor progression. Nature 3，147（2019）. 5. Chia，K.，Keatinge，M.，Mazzolini，J. & Sieger，D.脑肿瘤将内源性神经元重新用于小胶质细胞信号传导机制，以促进其自身增殖。Elife 8，19（2019）. 6. Miyamoto，A.小胶质细胞接触诱导发育中的体感皮层中的突触形成。Nature Communications 1-12（2019）. 7.坎宁安角L.，Martinez-Cerdeno，V. & Noctor，S. C.小胶质细胞调节发育中大脑皮层神经前体细胞的数量。Journal of Neuroscience 33，4216-4233（2013）. 8.上野，M。& Yamashita，T.发育中大脑中小胶质细胞的双向调节：从神经发生到神经回路形成。Current Opinion in Neurobiology 27，8- 15（2014）. 9. Mosser，C.-一、Baptista，S.，阿尔努岛& Audinat，E. CNS发育中的小胶质细胞：塑造未来的大脑。Progress in Neurobiology 149-150，1-20（2017）。