MnSOD expression is less frequent in tumour cells of invasive breast carcinomas than inin situcarcinomas or non-neoplastic breast epithelial cells
- 11 July 2001
- journal article
- research article
- Published by Wiley in The Journal of Pathology
- Vol. 195 (2) , 156-162
- https://doi.org/10.1002/path.946
Abstract
Manganese superoxide dismutase (MnSOD) is an antioxidant enzyme capable of neutralizing superoxide anion molecules. In previous studies it has been suggested to suppress both tumour proliferation and apoptosis. This study investigated 65 invasive, 50 in situ and 19 benign hyperplastic breast lesions for its immunohistochemical expression. MnSOD expression was also tested with in situ hybridization. To study cell proliferation, apoptosis and their association with MnSOD expression the neoplastic breast lesions were immunostained with a monoclonal antibody to Ki‐67 and the extent of apoptosis in them was determined by the TUNEL method. 32/65 (49%) of the invasive ductal carcinomas, 41/50 (82%) of the in situ and 15/19 (79%) of the benign hyperplasias expressed the MnSOD protein. There were significantly more MnSOD positive cases in in situ carcinoma and in benign hyperplasia than in invasive carcinoma (p=0.00016 and p=0.022, respectively). Positivity was also more frequently found in non‐neoplastic ductal and acinar epithelial cells than in invasive carcinoma. On the other hand, neoplastic epithelial cells of invasive and in situ carcinoma showed strong positivity more often than the epithelial cells of benign hyperplasia or non‐neoplastic epithelium. In breast lesions, MnSOD positivity did not associate with proliferation or apoptosis. The lower frequency of MnSOD positive cases in invasive breast carcinoma suggests that the lack of its expression might contribute to the development of an invasive breast carcinoma phenotype and that it could in this way operate as a tumour suppressor gene, as previously suggested. Copyright © 2001 John Wiley & Sons, Ltd.Keywords
Funding Information
- Finnish Cancer Societies
- Finnish Anti-Tuberculosis Association Foundation
This publication has 36 references indexed in Scilit:
- Protein Kinase Cδ-dependent Induction of Manganese Superoxide Dismutase Gene Expression by Microtubule-active Anticancer DrugsPublished by Elsevier ,1998
- Redox Gene Therapy Protects Human IB-3 Lung Epithelial Cells Against Ionizing Radiation-Induced ApoptosisHuman Gene Therapy, 1998
- Protective roles of cytokines against radiation: Induction of mitochondrial MnSODBiochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, 1995
- Oxy-radicals and cancerThe Lancet, 1994
- Manganese superoxide dismutase content and localization in human thyroid tumoursThe Journal of Pathology, 1993
- Superoxide dismutase activity and superoxide dismutase-1 gene methylation in normal and tumoral human breast tissuesCancer Genetics and Cytogenetics, 1992
- Extent, distribution, and mammographic/ histological correlations of breast ductal carcinoma in situThe Lancet, 1990
- Oxidative Stress and Tumour Cell ProliferationFree Radical Research Communications, 1990
- Isolation and characterization of complementary DNAs encoding human manganese‐containing superoxide dismutaseFEBS Letters, 1988
- Protection against oxygen toxicity by intravenous injection of liposome-entrapped catalase and superoxide dismutase.Journal of Clinical Investigation, 1984