Purification of glioma-derived motility factor and its biological role in tumor invasion

我们之前已经证明，人类恶性胶质瘤细胞T98G分泌一种刺激产生细胞运动的因子（J neurosurgery 73: 881-888, 1990）。通过明胶亲和层析、肝素亲和-、DEAE阴离子交换-、羟基磷灰石-、凝胶渗透-和磺胺丙基高效液相层析，从无血清条件培养基T98G中纯化出胶质瘤源性运动因子（GMF）。GMF由两个分子种组成：GMF- i和GMF- ii，分子量分别为145 kDa和165 kDa。这两种转基因食品的理化特性在氨基酸组成方面是相似的。GMF-I和GMF-II均以浓度依赖性的方式刺激T98G细胞的迁移，且GMF-I的活性是GMF-II的5 ~ 10倍。格子板分析表明，GMFs对T98G细胞不仅具有趋化作用，而且具有趋化动力学作用，在重建基底膜Matrigel的体外入侵实验中，T98G细胞和T98G细胞都表现出高侵袭性，向GMFs迁移的强度很大，而A172、9L胶质瘤细胞和正常胶质细胞对Matrigel屏障的浸润较弱，向GMFs迁移的强度较小。这些结果表明，胶质瘤细胞对GMFs的迁移反应与侵袭性密切相关，提示GMFs在胶质瘤细胞侵袭过程中发挥重要作用。

We have previously demonstrated that human malignant glioma cells, T98G, secrete a factor taht stimulates the motility of the producer cells (J Neurosurg 73 : 881-888, 1990). The glioma-derived motility factor (GMF) has been purified to homogeneity from the serum-free conditioned medium of T98G by gelatin affinity chromatography and heparin affinity-, DEAE anion exchange-, hydroxyapatite-, gel permiation- and sulfopropyl high performance liquid chromatography. The GMF consisted of two molecular species, GMF-I and GMF-II, whose molecular mass were 145 kDa and 165 kDa, respectively. The physicochemical characteristics of these two GMFs are similar with respect to amino acid composition. GMF-I and GMF-II both stimulated the migration of T98G cells in a concentration-dependent manner, and the activity of GMF-I was 5 to 10 times as strong as that of GMF-II.Checcurboard analysis demonstrated that the GMFs had not only a chemotactic effect but also a chemokinetic effect on T98G cells, both of which showed high invasiveness in an invitro invation assay with reconstituted basement membrane, Matrigel, migrated to the GMFs with great intensity, while A172 and 9L glioma cells and normal glial cells, all of which weakly infiltrated the Matrigel barrier, migrated to the GMFs with much less intensity. These results indicate that migratory response of glioma cells to the GMFs correlates well with invasiveness, suggesting an important role of the GMFs in the process of gloma cell invasion.