Winkler Frank, Kienast Yvonne, Fuhrmann Martin, Von Baumgarten Louisa, Burgold Steffen, Mitteregger Gerda, Kretzschmar Hans, Herms Jochen
Department of Neurology, Ludwig-Maximilians University, Munich, Germany.
Glia. 2009 Sep;57(12):1306-15. doi: 10.1002/glia.20850.
Infiltration of cancer cells into normal tissue is a hallmark of malignant gliomas and compromises treatment options. A lack of appropriate models limits the study of this invasion in vivo, which makes it difficult to fully understand its anatomy and the role of dynamic interactions with structures of the normal brain. We developed a novel methodology by utilizing multiphoton laser scanning microscopy (MPLSM) to image the movement of glioma cells deep within the normal brain of live mice in real time. This allowed us to track the invasion of individual RFP-expressing GL261 cells in relation to perfused vasculature or GFP-labeled endothelial cells repetitively over days, up to a depth of 0.5 mm. Glioma cells moved faster and more efficiently when the abluminal site of a blood vessel was utilized for invasion. Cells that invaded perivascularly were frequently found next to (a) multiple capillary structures where microvessels run parallel to each other, (b) capillary loops or glomeruloid-like bodies, and (c) dilated capillaries. Dynamic MPLSM for more than 48 h revealed that single invasive glioma cells induced intussusceptive microvascular growth and capillary loop formation, specifically at the microvascular site with which they had contact. As the main tumor grew by cooption of existing brain vessels, these peritumoral vascular changes may create a beneficial environment for glioma growth. In conclusion, our study revealed new mechanisms of peritumoral angiogenesis and invasion in gliomas, providing an explanation for their interdependence.
癌细胞浸润到正常组织是恶性胶质瘤的一个标志,并且会影响治疗方案。缺乏合适的模型限制了对这种体内侵袭的研究,这使得难以充分理解其解剖结构以及与正常脑组织结构动态相互作用的作用。我们开发了一种新方法,利用多光子激光扫描显微镜(MPLSM)实时成像活小鼠正常脑内深处胶质瘤细胞的运动。这使我们能够在数天内重复跟踪单个表达红色荧光蛋白的GL261细胞相对于灌注血管或绿色荧光蛋白标记的内皮细胞的侵袭情况,深度可达0.5毫米。当利用血管的无腔侧进行侵袭时,胶质瘤细胞移动得更快且更有效。血管周围侵袭的细胞经常出现在以下位置:(a)多个微血管相互平行的毛细血管结构旁;(b)毛细血管袢或肾小球样体;(c)扩张的毛细血管。超过48小时的动态MPLSM显示,单个侵袭性胶质瘤细胞可诱导套叠式微血管生长和毛细血管袢形成,特别是在它们接触的微血管部位。随着主要肿瘤通过合并现有的脑血管而生长,这些肿瘤周围的血管变化可能为胶质瘤生长创造有利环境。总之,我们的研究揭示了胶质瘤肿瘤周围血管生成和侵袭的新机制,解释了它们的相互依存关系。