The role of miRNA-15a in diagnostics of renal cell carcinoma

Abstract

Renal cell carcinoma (RCC) – is the most common primary tumor of the kidney. The part of nondiagnostic percutaneous core biopsy (PCB) of the kidney varies from 5 to 40%. The application of imaging methods of examination, such as CT or MRI don’t guarantee 100% sensitivity and specificity for diagnosis of RCC, remaining within 88–96%. The objective: the goal of the investigation was to estimate the value of application of the miRNA-15a expression in urine as a biomarker of RCC. Patients and methods. The study enrolled 67 adult patients with solid renal neoplasms: RCC (n=58), benign renal tumors (n=15). The medium age was 60,19±6,36 years, the medium size of the tumor was 7,01±2,08 sm. All patients were treated by surgery. One day before and after the 8th day after the surgery in all patients and once in 30 healthy volunteers without renal pathology 100–150 ml of urine was collected with further definition of expression by using reverse transcription and PCR in real time. Results. For the first time significant difference (р<0,05) was detected between medium values of miR-15a expression in urine of the patients with RCC, benign renal tumors and healthy people: 2,50E-01±2,72E-01 УО vs 1,32E-03±3,90E-03 vs 3,36E-07±1,04E-07 УО accordingly. The strong correlation between the size of RCC and the level of miR-15a expression was observed (r=0,87). The sensitivity and specificity during differentiation of RCC and benign renal tumors using the threshold 03±5,18E-03 УО were 98,1% and 100% accordingly. Conclusion. Application measured in urine miR-15a expression may be used as a biomarker of RCC. Further studies are required with inclusion of bigger quantity of patients with different histological subtypes of RCC and grades of differentiation, benign renal tumors for more depth analysis of diagnostic value of miR-15a Further studies are needed for finding out the reason of miR-15a upregulation in urine of the patients with RCC, considering its tumor-protective features, which are described in literature.