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

我们以前已经证明，人恶性神经胶质瘤细胞T98 G分泌刺激生产细胞运动的因子（J Neurosurg 73：881-888，1990）。用明胶亲和层析、肝素亲和层析、DEAE阴离子交换层析、羟基磷灰石层析、凝胶渗透层析和磺丙基高效液相层析从T98 G无血清条件培养液中纯化胶质瘤源性运动因子（GMF）。GMF由两种分子组成，GMF-I和GMF-II，其分子量分别为145 kDa和165 kDa。这两种GMF的理化特性在氨基酸组成方面相似。GMF-I和GMF-II均以浓度依赖方式刺激T98 G细胞迁移，GMF-I的活性是GMF-II的5 ~ 10倍。体外实验表明，GMF-I和GMF-II对T98 G细胞不仅具有趋化作用，而且具有趋化动力学作用。以高强度迁移到GMF，而A172和9 L胶质瘤细胞和正常胶质细胞，所有这些都弱地浸润Matrigel屏障，以低得多的强度迁移到GMF。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起重要作用。

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.