Zagzag David, Shiff Bronya, Jallo George I, Greco M Alba, Blanco Cy, Cohen Henry, Hukin Juliette, Allen Jeffrey C, Friedlander David R
Microvascular and Molecular Neuro-oncology Laboratory, New York University Medical Center, New York, New York 10016, USA.
Cancer Res. 2002 May 1;62(9):2660-8.
Enhanced expression of tenascin-C (TN-C) at the invasive edges of glioblastoma multiforme in close association with vascular sprouts, suggests a role for TN-C in microvascular cell migration. To test this hypothesis, we studied the migration of endothelial cells in vitro. In an aggregate migration assay, bovine retinal endothelial cells (BRECs) and human umbilical vein endothelial cells spread and migrated similarly on TN-C or fibronectin (FN). In contrast, U251 MG glioma cells migrated less on TN-C than on FN. Morphological features of U251 MG glioma cells on TN-C included poor cell spreading and short processes. In contrast, on FN, U251 MG glioma cells spread and exhibited long radial processes. Using a transmembrane migration assay, we observed that BREC adhesion was similar on TN-C or FN, whereas U251 MG glioma cells adhered better to FN than to TN-C. In addition, BRECs migrated more across the membrane toward regions coated with TN-C than FN, and conversely, U251 MG glioma cells migrated more toward FN than TN-C. Migration of endothelial and glioma cells toward TN-C or FN occurred in a dose-dependent manner and was strongly dependent on cell adhesion. In this assay, ultrastructural study revealed the migrating phenotype of the endothelial cells through the micropores of the membrane and their spread morphology on TN-C. Moreover, in situ hybridization revealed specific expression of TN-C in migrating microvascular cells in a cerebral microvascular ring assay. Finally in a phosphorylation assay, TN-C enhanced focal adhesion kinase phosphorylation of BRECs, but not of U251 MG glioma cells, and FN enhanced focal adhesion kinase phosphorylation of both BRECs and U251 MG cells. The expression of TN-C by migrating endothelial cells and the promotion of endothelial cell adhesion and migration by TN-C suggest a potential role for TN-C in pathological angiogenesis.
在多形性胶质母细胞瘤的侵袭边缘，腱生蛋白-C（TN-C）表达增强，且与血管芽紧密相关，提示TN-C在微血管细胞迁移中发挥作用。为验证这一假说，我们在体外研究了内皮细胞的迁移。在聚集迁移试验中，牛视网膜内皮细胞（BRECs）和人脐静脉内皮细胞在TN-C或纤连蛋白（FN）上的铺展和迁移情况相似。相比之下，U251 MG胶质瘤细胞在TN-C上的迁移比在FN上少。U251 MG胶质瘤细胞在TN-C上的形态学特征包括细胞铺展不佳和突起短。相比之下，在FN上，U251 MG胶质瘤细胞铺展并呈现出长的放射状突起。使用跨膜迁移试验，我们观察到BRECs在TN-C或FN上的黏附情况相似，而U251 MG胶质瘤细胞对FN的黏附比对TN-C更好。此外，BRECs穿过膜向涂有TN-C的区域迁移比向涂有FN的区域更多，相反，U251 MG胶质瘤细胞向FN迁移比向TN-C更多。内皮细胞和胶质瘤细胞向TN-C或FN的迁移呈剂量依赖性，且强烈依赖于细胞黏附。在该试验中，超微结构研究揭示了内皮细胞通过膜微孔的迁移表型及其在TN-C上的铺展形态。此外，原位杂交显示在脑微血管环试验中，TN-C在迁移的微血管细胞中有特异性表达。最后在磷酸化试验中，TN-C增强了BRECs的粘着斑激酶磷酸化，但未增强U251 MG胶质瘤细胞的粘着斑激酶磷酸化，而FN增强了BRECs和U251 MG细胞的粘着斑激酶磷酸化。迁移的内皮细胞表达TN-C以及TN-C促进内皮细胞黏附和迁移，提示TN-C在病理性血管生成中可能发挥作用。
