Quantitative Study of Invasiveness of Malignant Gliomas

目前，恶性胶质瘤仍难以治愈，主要原因是其侵袭性生长至周围正常脑组织。为了阐明神经胶质肿瘤的侵袭性，我们研究了一种细胞粘附分子，N-钙粘蛋白，它负责神经组织中细胞间的粘附。在这项研究中，我们研究了N-cadherin mRNA在大鼠胶质瘤细胞系9 L，C6，RG 12中的表达与这些细胞的粘附程度之间的相关性，通过体外细胞聚集试验评估。在北方印迹分析中，三种不同大小的N-钙粘蛋白转录本在所有三种大鼠胶质瘤细胞系中被鉴定，而在正常脑组织中仅识别出两种大小的条带。这三条带的表达程度在每条带的大小以及每个细胞系中不同。其中最大条带（5.2Kb）的表达程度差异较大，RG 12表达较强，9 L表达中等，C6表达较弱，其表达程度与体外细胞聚集实验测定的细胞粘附程度有关。这些结果表明，N-cadherin在胶质瘤细胞的细胞间粘附中起作用，并参与胶质瘤的侵袭。

At presnt, it is still difficult to cure patients with malignant glial tumors, mainly because of invasive growth into surrounding normal brain tissue. To clarify the invasion of glial tumors, we studied one of the cell adhesion molecules, N-cadherin, which is responsible for cell-cell adhesion in neural tissue. In this study, we investigated the correlation between expression of N-cadherin mRNA in rat glioma cell lines 9L,C6, RG12 and the extent of adhesion of these cells evaluated by in vitro cell aggregation assay. In Northern blot analysis, three different sizes of N-cadherin transcripts were identified in all three rat glioma cell lines, wheres only two sizes of bands were recognized in normal brain tissue. The degree of expression of these three bands varied amang each band size as well as each cell line. Especially, the degree of expression of the largest band (5.2Kb) varied considerably, strong in RG12, medium in 9L and weak in C6, and the degree of expression was related to the extent of adhesion of these cell lines estimated by in vitro cell aggregation assay. These results suggest that N-cadherin plays a role in cell-cell adhesion in glioma cells, and is involved in the invasion of glial tumors.