Cobbs C S, Levi D S, Aldape K, Israel M A
Department of Neurological Surgery, University of California, San Francisco, San Francisco, California 94143-0520, USA.
Cancer Res. 1996 Jul 15;56(14):3192-5.
Manganese superoxide dismutase (MnSOD) is a superoxide anion scavenger located in mitochondria. Increased expression of MnSOD can diminish oxygen radical-mediated injuries and the cytotoxic effects of tumor necrosis factor alpha, ionizing radiation, and certain chemotherapeutic agents. We used immunohistochemical staining to analyze 42 specimens of human brain tumors and 3 normal brain controls with a polyclonal antibody recognizing human MnSOD. We measured MnSOD in cerebrospinal fluid (CSF) from 14 patients with brain tumors and 7 control patients using an ELISA. Although MnSOD is not readily detected in normal brain, malignant central nervous system tumors, including tumors metastatic to the brain, displayed marked immunoreactivity to MnSOD intracellularly, in the extracellular matrix and in the tumor endothelial cells. Grade IV astrocytomas (glioblastomas), Grade III astrocytomas, and medulloblastomas were strongly immunoreactive, whereas Grade II astrocytomas had much less immunoreactivity. ELISA analysis of CSF samples from patients with malignant tumors also revealed high levels of MnSOD protein, up to 45-fold greater than the level of control CSF samples.
锰超氧化物歧化酶（MnSOD）是一种位于线粒体中的超氧阴离子清除剂。MnSOD表达的增加可以减轻氧自由基介导的损伤以及肿瘤坏死因子α、电离辐射和某些化疗药物的细胞毒性作用。我们使用一种识别人类MnSOD的多克隆抗体，通过免疫组织化学染色分析了42例人类脑肿瘤标本和3例正常脑对照。我们使用酶联免疫吸附测定法（ELISA）测量了14例脑肿瘤患者和7例对照患者脑脊液（CSF）中的MnSOD。虽然在正常脑中不易检测到MnSOD，但恶性中枢神经系统肿瘤，包括脑转移瘤，在细胞内、细胞外基质和肿瘤内皮细胞中对MnSOD表现出明显的免疫反应性。IV级星形细胞瘤（胶质母细胞瘤）、III级星形细胞瘤和髓母细胞瘤具有强烈的免疫反应性，而II级星形细胞瘤的免疫反应性则低得多。对恶性肿瘤患者脑脊液样本的ELISA分析还显示，MnSOD蛋白水平很高，比对照脑脊液样本的水平高出45倍。
