Vandeputte Dmitri A A, Troost Dirk, Leenstra Sieger, Ijlst-Keizers Helen, Ramkema Marja, Bosch D Andries, Baas Frank, Das Nab K, Aronica Eleonora
Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Glia. 2002 Jun;38(4):329-38. doi: 10.1002/glia.10076.
The Id family of helix-loop-helix proteins is involved in a variety of processes, such as development, proliferation, and angiogenesis. In this study, we investigated the expression pattern of Id1, Id2, and Id3 in surgical specimens of human glial tumors. Western blot analysis demonstrated that all three Id proteins were expressed in astrocytic tumors. Expression levels in high-grade tumors were higher than in low-grade tumors. Immunohistochemical analysis confirmed that many of the tumor astrocytes exhibited strong Id1-3 IR. In contrast, in adult human normal brain, Id expression was low both in resting astrocytes and in endothelial cells. In tumor cells, Id proteins displayed cytoplasmic as well as nuclear localization. Id1-3 IR scores in tumor cells were positively correlated with proliferation indices. Moreover, Id1-3 IR was detected in endothelial cells of the astrocytic tumor blood vessels. The vascular Id1-3 expression correlated positively with tumor vascularity and grade. These results support the role of the Id gene family in the enhanced proliferative potential of tumor astrocytes. The evidence also supports the involvement of the Id gene family in tumor angiogenesis, a process that critically influences the malignant behavior of glial tumors.
螺旋-环-螺旋蛋白的Id家族参与多种过程，如发育、增殖和血管生成。在本研究中，我们调查了Id1、Id2和Id3在人类胶质肿瘤手术标本中的表达模式。蛋白质印迹分析表明，所有三种Id蛋白均在星形细胞瘤中表达。高级别肿瘤中的表达水平高于低级别肿瘤。免疫组织化学分析证实，许多肿瘤星形细胞表现出强烈的Id1-3免疫反应性。相比之下，在成人人正常大脑中，静止星形细胞和内皮细胞中的Id表达均较低。在肿瘤细胞中，Id蛋白表现出胞质和核定位。肿瘤细胞中的Id1-3免疫反应性评分与增殖指数呈正相关。此外，在星形细胞瘤血管的内皮细胞中检测到Id1-3免疫反应性。血管Id1-3表达与肿瘤血管生成和分级呈正相关。这些结果支持Id基因家族在肿瘤星形细胞增殖潜能增强中的作用。证据还支持Id基因家族参与肿瘤血管生成，这一过程对胶质肿瘤的恶性行为至关重要。
