Oberley L W, Oberley T D
Department of Radiology, University of Iowa, Iowa City 52242.
Mol Cell Biochem. 1988 Dec;84(2):147-53. doi: 10.1007/BF00421049.
The role of antioxidant enzymes, particularly superoxide dismutase (SOD), in immortalization and malignant transformation is discussed. SOD (generally MnSOD) has been found to be lowered in a wide variety of tumor types when compared to an appropriate normal cell control. Levels of immunoreactive MnSOD protein and mRNA for MnSOD also appear to be lowered in tumor cells. Tumor cells have the capacity to produce superoxide radical, the substrate for SOD. This suggests that superoxide production coupled with diminished amounts of MnSOD may be a general characteristic of tumor cells. The levels of MnSOD in certain cells correlates with their degree of differentiation; non-differentiating cells, whether normal or malignant, appear to have lost the ability to undergo MnSOD induction. These observations are used to elucidate a two-step model of cancer. This model involves not only the antioxidant enzymes, but also organelle (particularly mitochondria and peroxisomes) function as a dominant theme in carcinogenesis.
本文讨论了抗氧化酶，特别是超氧化物歧化酶（SOD）在永生化和恶性转化中的作用。与适当的正常细胞对照相比，已发现SOD（通常为MnSOD）在多种肿瘤类型中含量降低。肿瘤细胞中免疫反应性MnSOD蛋白和MnSOD mRNA的水平似乎也降低。肿瘤细胞有能力产生超氧阴离子，即SOD的底物。这表明超氧阴离子的产生与MnSOD含量的减少可能是肿瘤细胞的一个普遍特征。某些细胞中MnSOD的水平与其分化程度相关；未分化的细胞，无论是正常细胞还是恶性细胞，似乎都失去了进行MnSOD诱导的能力。这些观察结果被用于阐明癌症的两步模型。该模型不仅涉及抗氧化酶，还涉及细胞器（特别是线粒体和过氧化物酶体）功能，这是致癌作用中的一个主导主题。
