Prognostic role of myoferlin expression in patients with clear cell renal cell carcinoma

// Dae Hyun Song 1, 2, 4 , Gyung Hyuck Ko 1, 2, 3 , Jeong Hee Lee 1, 2, 3 , Jong Sil Lee 1, 2, 3 , Jung Wook Yang 3 , Min Hye Kim 3 , Hyo Jung An 4 , Myoung Hee Kang 1, 2, 5 , Kyung Nyeo Jeon 1, 2, 6 and Dong Chul Kim 1, 2, 3 1 Gyeongsang National University School of Medicine, Jinju, South Korea 2 Gyeongsang Institute of Health Science, Gyeongsang National University, Jinju, South Korea 3 Department of Pathology, Gyeongsang National University Hospital, Jinju, South Korea 4 Department of Pathology, Gyeongsang National University Changwon Hospital, Changwon, South Korea 5 Department of Internal Medicine, Gyeongsang National University Changwon Hospital, Changwon, South Korea 6 Department of Radiology, Gyeongsang National University Changwon Hospital, Changwon, South Korea Correspondence to: Dong Chul Kim, email: kdcjes@gmail.com Keywords: clear cell renal cell carcinoma, myoferlin, prognosis, disease-free survival, immunohistochemistry Received: July 04, 2017 Accepted: August 27, 2017 Published: October 06, 2017 ABSTRACT Objectives: In patients with cancer, myoferlin protein hyperexpression has been correlated with poor patient prognosis. Here, we evaluated myoferlin expression in patients with clear cell renal cell carcinoma (ccRCC) and investigated the prognostic significance of myoferlin expression in these patients. Materials and Methods: One hundred and fifty-two patients with ccRCC who underwent treatment at Gyeongsang National University Hospital, Korea, between January 2000 and December 2009 were enrolled. Immunohistochemical analysis was performed on tissue microarray blocks produced from surgical specimens. Surgical specimen cancerous cells were graded as showing myoferlin hyperexpression or hypoexpression by comparison with intratumoral endothelial cells. Disease-free survival was evaluated using Kaplan-Meier analysis. Cox regression analysis was used to determine the relationships between myoferlin expression levels, risk factors, and prognosis. Results: Seventy-one of 304 cores exhibited myoferlin hyperexpression. T stage was not associated with myoferlin hyperexpression, whereas a high Fuhrman nuclear grade was significantly associated with myoferlin hyperexpression. Kaplan-Meier analysis revealed that patients with T stage >2, Fuhrman nuclear grade >2, and those with myoferlin hyperexpression had poorer disease-free survival compared to those with lower T stage, lower Fuhrman nuclear grade, and myoferlin hypoexpression (all p