Plasma thymosin-α1 level as a potential biomarker in urothelial and renal cell carcinoma.

OBJECTIVES: To determine the plasma levels of thymosin-α1 (TA1) and prothymosin-α (PTMA) proteins in renal cell carcinoma (RCC) or urothelial carcinoma (UC) patients, and explore the potential of these 2 molecules as biomarkers. MATERIALS AND METHODS: Blood samples were taken from 50 consecutive patients with RCC, 97 with UC, and 55 with benign urologic diseases before surgery. Their clinical characteristics were obtained from medical record review. Plasma TA1 and PTMA levels were measured using enzyme-linked immunosorbent assay and their correlation with tumor grade, pathologic stage, and survival were explored. RESULTS: Plasma TA1 levels were significantly lower in RCC patients than in UC or benign patients, particularly in UC of the renal pelvis patients (P < 0.0001). Plasma PTMA levels were also significantly lower in UC patients compared with RCC patients and benign patients (P < 0.05). Plasma TA1 levels inversely correlated with pathologic stage both in bladder cancer and RCC patients (P = 0.03 and 0.02, respectively). Both plasma TA1 and PTMA did not correlate with tumor grade. Plasma TA1 was a prognostic indicator for progression-free and disease-specific overall survival in bladder cancer patients (P = 0.008 and 0.04, respectively). CONCLUSIONS: Plasma TA1 level may be a biomarker for differentiating between UC and RCC. It may also be a prognostic factor for disease progression and disease-specific survival in bladder cancer patients. These findings warrant more studies for validation.