Su-P057 EXPRESSION OF BONE MORPHOGENETIC PROTEINS AND THEIR RECEPTORS IN NORMAL HUMAN KIDNEY AND RENAL CELL CARCINOMA
D. Bobinac*1, T. Celic1, D. Markic2, J. Spanjol2, A. Grskovic2, I. Maric1, Z. Fuckar2
1Department of Anatomy, Faculty of Medicine, 2Department of Urology, Clinical Hospital Rijeka, Rijeka, Croatia
Background/aims: Bone morphogenetic protein (BMP), a member of the TGF-beta superfamily, is involved in development, morphogenesis, cell proliferation and apoptosis. The BMPs are produced as precursor proteins, which are cleaved forming a mature active protein. Mature BMP binds heteromeric complex of serine kinase receptors BMPR-IA/IB and BMPR-II which then phosphorylates and activates Smad 1, 5 and 8 transcript factors. Different members of BMPs family have been investigated in malignant disease of various organs. Dysregulation of BMP expression has been reported in tumorigenesis. Previous results have shown dysregulation of some BMPs and their receptors in renal cell carcinoma, too. We investigated the protein expression of bone morphogenetic protein-6 and-7 and their receptors BMPR-IB and BMPR-II in patients with different type of renal cell carcinoma as well as in healthy kidney tissue.
Patients and Methods: After nephrectomy due to renal cancer, tissue samples of renal cancer were taken and frozen at -80 degrees. Normal tissue sample was taken from the same kidney and served as control. Pathohistological analysis of renal tissue confirmed two types of renal cell carcinoma (RCC), RCC-clear cell and RCC-chromophobe type. For Western blot analysis we used goat polyclonal antibodies, anti-BMP-6, anti-BMP-7, anti-BMPR-IB and anti BMPR-II (Santa CruzBiotechnology, USA). For normalizing we used beta-actin (R&D Systems). The bands were visualized and quantified using Kodak 1D image analysis software.
Results: The protein expression of BMP-6, BMP-7, BMPR-IB and BMPR-II was detected in normal kidney tissue and in renal cell carcinoma tissue. RCC-clear cell and RCC-chromophobe type showed different level of protein expression toward expression in normal kidney tissue. The expression of BMP-6 and -7 was lower in RCC-clear cell as well as in RCC-chromophobe type than in normal kidney tissue. RCC-chromophobe type showed higher expression of BMPR-IB and BMPR-II than normal kidney tissue. Unlike RCC-chromophobe type, RCC-clear cell showed decreased expression for BMPR-IB and BMPR-II.
Conclusion: In the present study the correlation between the expression of bone morphogenetic proteins as well as their receptors and subtype of renal cell carcinoma was found.
Conflict of Interest: None declared