Landolt H, Langemann H, Probst A, Gratzl O
Department of Neurosurgery, Cantonal Hospital, Basel, Switzerland.
J Neurooncol. 1994;21(2):127-33. doi: 10.1007/BF01052896.
The aim of the present study was to investigate the oxidative status in astrocytoma. Samples of brain tissue from the centre to the periphery of the tumor were obtained from 11 astrocytoma patients undergoing computer tomography-guided stereotaxic operation, who had been previously treated with the corticosteroid dexamethasone. Part of the sample was investigated histologically for clarification of tumor type, and the presence of neoplastic and non-neoplastic tissue and necrosis. The rest was used for the quantification of the antioxidants ascorbic acid, uric acid, glutathione and cysteine by high performance liquid chromatography, and for quantification of DNA. Levels of antioxidants were calculated as micrograms/g fresh tissue and mumol/g DNA, a parameter related to cell content. There was significantly more DNA in neoplastic samples than in non-neoplastic ones, indicating increased cell density. Uric acid (micrograms/g fresh tissue) was significantly increased in neoplastic compared with non-neoplastic tissue, and levels were even higher in necrotic tissue. There were no significant differences between neoplastic and non-neoplastic tissue levels of ascorbic acid, glutathione or cysteine, expressed as micrograms/g fresh tissue. However, when levels of these three compounds were expressed as mumol/g DNA, i.e. taking into account the higher cell density, ascorbic acid, glutathione and cysteine were significantly reduced in neoplastic samples compared with non-neoplastic ones. Results thus show that there are differences between the antioxidant levels in astrocytoma and non-neoplastic tissue, providing additional support for the hypothesis that free radicals play a role in tumor growth.
本研究的目的是调查星形细胞瘤中的氧化状态。从11名接受计算机断层扫描引导的立体定向手术的星形细胞瘤患者身上获取了从肿瘤中心到周边的脑组织样本，这些患者此前已接受皮质类固醇地塞米松治疗。对部分样本进行组织学检查以明确肿瘤类型、肿瘤组织与非肿瘤组织的存在情况以及坏死情况。其余样本用于通过高效液相色谱法定量抗氧化剂抗坏血酸、尿酸、谷胱甘肽和半胱氨酸，并用于定量DNA。抗氧化剂水平以微克/克新鲜组织和微摩尔/克DNA计算，后者是与细胞含量相关的参数。肿瘤样本中的DNA明显多于非肿瘤样本，表明细胞密度增加。与非肿瘤组织相比，肿瘤组织中的尿酸（微克/克新鲜组织）显著增加，坏死组织中的水平更高。以微克/克新鲜组织表示，肿瘤组织与非肿瘤组织中的抗坏血酸、谷胱甘肽或半胱氨酸水平没有显著差异。然而，当这三种化合物的水平以微摩尔/克DNA表示，即考虑到更高的细胞密度时，与非肿瘤样本相比，肿瘤样本中的抗坏血酸、谷胱甘肽和半胱氨酸显著降低。因此，结果表明星形细胞瘤与非肿瘤组织中的抗氧化剂水平存在差异，为自由基在肿瘤生长中起作用的假说提供了额外支持。
