Bravard A, Beaumatin J, Dussaulx E, Lesuffleur T, Zweibaum A, Luccioni C
CEA/DSV/DPTE/LCG, Fontenay-aux-Roses, France.
Int J Cancer. 1994 Dec 15;59(6):843-7. doi: 10.1002/ijc.2910590622.
The anti-oxidant metabolism was studied at different times after sub-culture in 2 colon cell lines previously characterized for their growth and differentiation properties. The HT29 cell line is mainly composed of proliferative and undifferentiative cells, while the derived 5-fluorouracil (FUra)-adapted cells undergo growth-dependent differentiation, which is complete at post-confluence. In the 2 cell lines, all the anti-oxidant parameters studied appeared to be related to proliferation, with increased activity of superoxide dismutase (SOD) 1 and 2, catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GSR), and glutathione transferase (GST), and decreased glucose-6-phosphate dehydrogenase (G6PD) activity and glutathione content, in parallel with slowing down of proliferation. At post-confluence, these metabolic parameters remained stable, except for GPX activity, which continued to increase, and CAT activity, which decreased. The amounts of SOD1, SOD2 and CAT immunoreactive proteins, estimated by Western blotting, appeared to be correlated to their respective enzymatic activities. SOD1, CAT and GST activity and glutathione content, which remained at similar levels in the 2 cell lines for all times studied, appeared unrelated to the differentiation process. GSR and GPX activity, which was lower in FUra-adapted than in parental cells only at post-confluence, could be considered as markers of differentiated cells. The higher SOD2 and lower G6PD activity observed in FUra-resistant cell in comparison with parental cells at all times after sub-culture could be characteristic both of differentiative and of differentiated cells. Interestingly, cytogenetics have previously indicated that deletions of the long arm of chromosome 6, which carry the gene for SOD2, were frequently observed in parental but not in FUra-adapted cells. These results demonstrate that modifications of the anti-oxidant metabolism occur in relation with proliferation and differentiation, and suggest a particular role for SOD2 in these cellular processes.
在两种先前已根据其生长和分化特性进行表征的结肠癌细胞系中，研究了传代培养后不同时间的抗氧化代谢情况。HT29细胞系主要由增殖性和未分化细胞组成，而衍生的5-氟尿嘧啶（FUra）适应性细胞经历生长依赖性分化，在汇合后完成。在这两种细胞系中，所研究的所有抗氧化参数似乎都与增殖有关，超氧化物歧化酶（SOD）1和2、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPX）、谷胱甘肽还原酶（GSR）和谷胱甘肽转移酶（GST）的活性增加，葡萄糖-6-磷酸脱氢酶（G6PD）活性和谷胱甘肽含量降低，同时增殖减缓。在汇合后，这些代谢参数保持稳定，除了GPX活性继续增加和CAT活性降低。通过蛋白质印迹法估计的SOD1、SOD2和CAT免疫反应蛋白的量似乎与其各自的酶活性相关。SOD1、CAT和GST活性以及谷胱甘肽含量在研究的所有时间内，在两种细胞系中都保持在相似水平，似乎与分化过程无关。GSR和GPX活性仅在汇合后在FUra适应性细胞中低于亲代细胞，可被视为分化细胞的标志物。与亲代细胞相比，在传代培养后的所有时间里，FUra抗性细胞中观察到的较高SOD2和较低G6PD活性可能是分化细胞和已分化细胞的特征。有趣的是，细胞遗传学先前表明，携带SOD2基因的6号染色体长臂缺失在亲代细胞中经常观察到，但在FUra适应性细胞中未观察到。这些结果表明，抗氧化代谢的改变与增殖和分化有关，并提示SOD2在这些细胞过程中具有特殊作用。
