Expression of Ring Box-1 protein and its relationship with Fuhrman grade and other clinical-pathological parameters in renal cell cancer

Objective: To determine the relationship between RING-box protein 1 (RBX-1) expression and renal cell carcinoma (RCC) with prognostic factors. Methods: A total of 88 patients who underwent radical/partial nephrectomy between January 2009 and January 2016 have been included in our study. The age, gender, tumor location, tumor size, and tumor-node-metastasis stage of each patient was evaluated. From the best sections in hematoxylin-eosin stained pathology preparations, tumor histological subtype, Fuhrman nuclear grade, lymphovascular invasion, renal artery/vein invasion, capsule invasion, perirenal fatty tissue invasion, and tumor grade were evaluated. Participants were divided into 2 groups according to Fuhrman grade. Fuhrman grades 1 to 2 comprised Group 1, and Fuhrman grades 3 to 4 comprised Group 2. An immunoreactivity scoring system was used to evaluate RBX-1 expression. Results: Upon examining all histological subtypes together, it was observed that RBX-1 expression was statistically higher in Group 2 compared to Group 1 (P < 0.008). Upon examining clear RCC cases, it was observed again that Group 2 had a higher RBX-1 expression than Group 1 (P < 0.009). RBX-1 expression was not associated with clinical-pathological parameters including tumor grade, lymphovascular invasion, capsule invasion, or perirenal invasion. Conclusion: RBX-1 expression is closely associated with a highly important prognostic factor in RCC—Fuhrman grade—and it shows promise as a prognostic marker. Further studies are required to reveal the importance of RBX-1 in RCC prognosis and treatment.