ABSTRACT Purposes: The aim of this study was to determine the diagnostic significance of fibronectin type III domain containing protein 5 (FNDC5)/Irisin levels in the sera of patients with renal cell cancer. Materials and Methods: In the study, 48 individuals were evaluated. The patient group included 23 subjects diagnosed with renal tumor, and the control group of 25 healthy individuals. Patients diagnosed with renal tumor received surgical treatment consisting of radical or partial nephrectomy. Blood specimens were collected and serum FNDC5/Irisin and carcinoembryonic antigen (CEA) levels were determined using enzyme-linked immunosorbent assay (ELISA). Results: FNDC5/irisin and CEA levels in renal cancer patients were significantly higher compared with the control group (p=0.0001, p=0.009, respectively). Also, FNDC5 levels was more sensitive and specific than CEA levels. The best cut-off points for FNDC5/irisin were >105pg/mL and CEA were >2.67ng/mL for renal cancer. Conclusions: FNDC5/Irisin may be used as a diagnostic biomarker for renal cancer.

ABSTRACT Purpose To investigate the efficacy of signal peptide-CUB-EGF domain-containing protein 1 (SCUBE-1) as a novel biomarker of renal tumors. Materials and Methods 48 individuals were included in the study. The patient group (Group-1) consisted of 23 subjects diagnosed with renal tumor, and the control group (Group-2) of 25 healthy individuals. Patients diagnosed with renal tumor received surgical treatment consisting of radical or partial nephrectomy. Blood specimens were collected following overnight fasting. Signal peptide-CUB-EGF domain-containing protein 1 (SCUBE-1), soluble urokinase plasminogen activator receptor (suPAR) and carbonic anhydrase IX (CA IX) levels were measured from plasma samples. Patients in groups 1 and 2 were compared in terms of these biochemical parameters. Results The 23-member renal tumor group was made up of 17 (73.91%) male and 6 (26.08%) female patients with a mean age of 58.5±15.7 years (range 25 to 80). The 24-member healthy control group was made up of 16 (64%) male and 9 (36%) female subjects with a mean age of 52.4±9.12 years (range 40 to 67). Analysis revealed significant elevation in SCUBE-1 levels in the renal tumor group (p=0.005). No significant differences were detected between the groups with regard to CA IX or suPAR measurements (p=0.062 vs. p=0.176). Conclusions SCUBE-1 appears to represent a promising biomarker in the diagnosis and follow-up of patients with renal tumor.