Immunocytochemical localization of c-myc and c-jun oncoproteins in hamster kidney and estrogen-induced kidney tumors

• Published in: The Journal of steroid biochemistry and molecular biology 1997, Vol.60 (1), p.99-104
• Main Authors: Bhat, Hari K., Springer, Ingo, Rajaraman, Srinivasan, Liehr, Joachim G.
• Format: Article
• Language: English
• Subjects: Animal tumors. Experimental tumors; Animals; Biological and medical sciences; Cricetinae; Estradiol - pharmacology; Estrogens - pharmacology; Experimental tumors, general aspects; Immunohistochemistry; Kidney - physiology; Kidney Neoplasms - chemically induced; Kidney Neoplasms - genetics; Male; Medical sciences; Proto-Oncogene Proteins c-jun - analysis; Proto-Oncogene Proteins c-jun - drug effects; Proto-Oncogene Proteins c-jun - immunology; Proto-Oncogene Proteins c-myc - analysis; Proto-Oncogene Proteins c-myc - drug effects; Proto-Oncogene Proteins c-myc - immunology; Tumors
• ISSN: 0960-0760; 1879-1220
• DOI: 10.1016/S0960-0760(96)00173-2

The chronic administration of 17β-estradiol to male Syrian hamsters for 6–7 months induces kidney tumors which express high levels of c-fos, c-myc and c-jun mRNA compared to surrounding tissue or untreated controls. In this study, we have investigated, by immunocytochemical methods, the cellular localization of c-myc and c-jun oncoproteins in estrogen-dependent kidney tumors, in kidney tissue of hamsters treated with 17β-estradiol for 6 months and in the kidneys of age-matched controls. The c-myc oncoprotein was strongly expressed in tumors, in smooth muscle layers of arteries and in parietal epithelial cells of the glomerulus. In age-matched untreated kidneys, there was little or no staining in the glomerulus, arteries or kidney tubular cells. The c-jun oncoprotein was detected in kidney tumors and in the tubular epithelium of surrounding tissue. The immunoreactivity for c-jun oncoprotein was highest in the tumor, intermediate in estrogen-treated kidney tissue and lowest in kidney tubular cells of controls. It is concluded that the high expression of c-myc in estrogen-induced kidney tumors, in the smooth muscle layer of arteries, and in glomerular parietal epithelial cells in the kidneys of 17β-estradiol-treated hamsters, but poor expression in control kidneys indicate an involvement of this oncoprotein in the tumorigenic process. In contrast, c-jun is expressed in untreated, in 17β-estradiol-treated kidneys and in tumors, and may not serve as a prognostic marker in the transformation of these cells to the malignant phenotype.