Mitochondrial PIWI-interacting RNAs are novel biomarkers for clear cell renal cell carcinoma.

PIWI-interacting RNAs (piRNAs) have been suggested to serve as biomarkers in cancer. In this study, we validated the expression profile of two piRNAs derived from mitochondria, piR-34536 and piR-51810, in tissue and serum of a cohort of clear cell renal cell carcinoma (ccRCC) patients.

Tissue and serum samples of patients with ccRCC were collected prospectively in our biobank. Total RNA was isolated from 118 ccRCC tissues, 75 normal renal tissues as well as 30 serum samples from patients with ccRCC, and 15 serum samples from patients with non-malignant diseases. The expression of piRNAs was determined using quantitative real-time PCR.

Both piR-34536 and piR-51810 were downregulated in ccRCC compared to non-malignant renal tissue. Decreased tissue piRNA levels were significant and independent predictors of shortened progression-free, cancer-specific and overall survival of ccRCC patients. The piRNA levels in serum did not differ in ccRCC patients and control subjects.

The expression of piR-34536 and piR-51810 in ccRCC tissues may be used as prognostic biomarkers in ccRCC.

World journal of urology. 2018 Nov 28 [Epub ahead of print]

Chenming Zhao, Yuri Tolkach, Doris Schmidt, Marieta Toma, Michael H Muders, Glen Kristiansen, Stefan C Müller, Jörg Ellinger

Department of Urology, University Hospital Bonn, Bonn, Germany., Department of Pathology, University Hospital Bonn, Bonn, Germany., Department of Urology, University Hospital Bonn, Bonn, Germany. .