MicroRNA-155 is a predictive marker for survival in patients with clear cell renal cell carcinoma

Objectives To investigate the clinical significance of micro-ribonucleic acid-155 in clear cell renal cell carcinoma, in particular focusing on the association of expression levels of micro-ribonucleic acid-155 with clinicopathological factors, cancer-specific survival and therapeutic outcomes in clear cell renal cell carcinoma patients. Methods Quantitative reverse transcription polymerase chain reaction of micro-ribonucleic acid-155 was carried out on 137 clear cell renal cell carcinoma cases, containing 77 matched pairs of clear cell renal cell carcinoma and normal adjacent kidney tissues from the same patients. Results Significant overexpression of micro-ribonucleic acid-155 was found in clear cell renal cell carcinoma compared with normal kidney tissue. Expression of micro-ribonucleic acid-155 was not associated with prognosis in all stage groups. However, in 43 patients with stageIII and IV clear cell renal cell carcinoma, low expression levels of micro-ribonucleic acid-155 correlated with a poor prognosis. Regarding cancer-free survival of 26 patients with stageIII and IV clear cell renal cell carcinoma who received curative resection and cancer-specific survival of 31 patients who received postoperative therapy with interferon- after radical nephrectomy, low expression levels of micro-ribonucleic acid-155 correlated with poor clinical outcomes in these two groups. Conclusions Low expression of micro-ribonucleic acid-155 represents a valuable marker of poor clinical outcomes in patients with stageIII and IV clear cell renal cell carcinoma.