Background/aim: Increased levels of microRNAs in serum/plasma have been identified in various malignancies. We aimed to investigate serum levels of miR-26a-1 and miR-141 in patients undergoing prostate biopsy clinical suspicious for prostate cancer (PCA) in a prospective multi-center study.
Patients and methods: Pre-biopsy serum samples of 170 patients were collected in three different study Centres. Serum RNA was isolated, and microRNA lev-els were quantified using real-time PCR. Relative miR-26a -1 and miR-141 levels were determined using RNU1-4 and SNORD43 as reference genes.
Results: After exclusion of pa-tients with metastatic prostate cancer (n=9) and isolation failures (n=28), 133 patients (prostate cancer n=54, non-malignant n=79) were used for further analysis. The levels of miR-26a-1 and miR-141 were similar in patients with positive and negative biopsies. We observed a significant increase of miR-141 in patients with higher Gleason Score.
Conclusion: The analysis of circulating microRNAs does not seem to help identify patients with cancer undergoing prostate biopsy. However, their levels may be useful to identify patients with high-risk prostate cancer.
Keywords: Prostate cancer; biomarker; miR-141; miR-26a-1; microRNA; serum.