Background: Brain tumors claimed the lives of 13,300 people in 1995. Our objective was to isolate and characterize unique tumor-suppressor genes from human brain tumors derived from patients in the United States. Methods: Differential display-polymerase chain reaction was used to isolate tumor suppr
SOD2: A new type of tumor-suppressor gene?
β Scribed by A. Bravard; L. Sabatier; F. Hoffschir; M. Ricoul; C. Luccioni; B. Dutrillaux
- Publisher
- John Wiley and Sons
- Year
- 1992
- Tongue
- French
- Weight
- 736 KB
- Volume
- 51
- Category
- Article
- ISSN
- 0020-7136
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
The activity of superoxide dismutases (SOD) I and 2 was analysed in correlation with mRNA and chromosome content in 6 SV40βtransformed (TF) and in nonβtransformed (NF) human fibroblast cell lines. Total SOD activity was fairly constant, whereas the ratio SOD2/SOD I was much lower in TF than in NF. The decrease in SOD2 activity was correlated with a low mRNA content, and with the presence of various chromosomal rearrangements leading to deletions of the long arm of chromosome 6 where the gene is mapped. In contrast, chromosome 21, carrying the gene for SODI, was not found to be deficient and the SODI activity was high. This shows that in TF, the activity of SOD2 is largely determined by gene dosage. It has been proposed that SOD activity could be inversely correlated with cell proliferation, and that SOD2 activity, in particular, was related to cell differentiation. Thus, there is a cascade of events occurring in cell transformation, involving gene deregulation, chromosome (gene) deletion, low mRNA and protein content, low enzyme activity, and acquisition of growth advantage which makes the SOD2 gene a possible new type of tumorβsuppressor gene.
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