Nygaard S J, Haugland H K, Kristoffersen E K, Lund-Johansen M, Laerum O D, Tysnes O B
Department of Pathology, Gade Institute, Bergen, Norway.
J Neurooncol. 1998 May;38(1):11-8. doi: 10.1023/a:1005953000523.
Annexin II is a calcium and phospholipid binding protein and a substrate for protein-tyrosine kinases. Increased levels of annexin II are observed in various cancer cells and tissues, and the molecule has been proposed as a marker of malignancy in vivo. Annexin II was expressed in four glioma cell lines (D-54MG, D-37MG, U251MG and GaMG), as determined by Western blot analyses, immunofluorescence staining and flow cytometric measurements. In addition, annexin II expression was also found in cryostat sections obtained from 15 consecutive brain tumor biopsies: Ten were histologically classified as glioblastomas, one as an astrocytoma, two as meningiomas and two as brain metastases. Cultured spheroids from the glioma cell lines and from three of the glioblastoma biopsies showed lower levels of annexin II, than found in the monolayers of the cell lines and in the freshly cut biopsies. The annexin II expression of the cell lines were not found to be related to their proliferative, migratory or invasive properties. These findings indicate that although annexin II may serve as a marker of malignancy in vivo, its expression can be reduced in vitro, and appear unrelated to malignant features of glioma cell lines.
膜联蛋白II是一种钙和磷脂结合蛋白，也是蛋白酪氨酸激酶的底物。在各种癌细胞和组织中均观察到膜联蛋白II水平升高，该分子已被提议作为体内恶性肿瘤的标志物。通过蛋白质印迹分析、免疫荧光染色和流式细胞术测量确定，膜联蛋白II在四种胶质瘤细胞系（D-54MG、D-37MG、U251MG和GaMG）中表达。此外，在连续15例脑肿瘤活检的冷冻切片中也发现了膜联蛋白II的表达：其中10例组织学分类为胶质母细胞瘤，1例为星形细胞瘤，2例为脑膜瘤，2例为脑转移瘤。来自胶质瘤细胞系和3例胶质母细胞瘤活检的培养球体中膜联蛋白II水平低于细胞系单层和新鲜切割活检中的水平。未发现细胞系的膜联蛋白II表达与其增殖、迁移或侵袭特性相关。这些发现表明，尽管膜联蛋白II可能作为体内恶性肿瘤的标志物，但其表达在体外可降低，且似乎与胶质瘤细胞系的恶性特征无关。
