Lucia Mésarošová1, Ján Švihra2, Jasna Šranková1, Ján Kliment2, Ján Kyselovič1, Ján Ľupták2, Pavol Slávik3, Peter Ochodnický4
Introduction and objectives: Clear cell renal cell carcinoma (CCRCC) represents 75-80 % of all histological subtypes and it is the most commonly occurring subtype of renal adenocarcinoma. Tissue hypoxia is the result of an imbalance in the supply of oxygen to the tissues, and its metabolic consumption. Hypoxia leads to activation of several genes encoding proteins involved in angiogenesis, erythropoiesis, and glucose metabolism. Aim of this study was to investigate the expression of erythropoietin (EPO) in tumour tissue after hypoxic conditions, with the aim to highlight its role in the development of clear cell renal cell carcinoma. Material and methods: In patients after radical nephrectomy tumour and control tissues were sampled, in which there were monitored changes in the expression of HIF-1α by immunoblot analysis and expression of EPO and EPOR using RT-PCR method. Results: We have observed neither change in HIF-1α expression nor in EPOR expression in tumour tissue compared with control one. By RT-PCR method we determined the expression of EPO, where our results showed an increased expression of EPO in tumours compared to control tissue. Conclusion: The function of EPO overexpression by cells in CCRCC has not been known yet, as only in 5 % of patients with RCC erythrocytosis is reported. The excessive EPO production in CCRCC cells is probably related to its proangiogenic, antiapoptotic and proliferative processes during tumourigenesis in neoplastic diseases.