Background: Expression profiles of some microRNAs (miRNAs) were associated with clinicopathological findings in human prostate cancer (PC), but the relative expression of miRNAs among Gleason patterns (GPs) remains unclear. In this study, we investigated the expression of several known microRNAs in each GP of PC.
Methods: Formalin-fixed, paraffin embedded (FFPE) tissue samples were obtained from radical prostatectomy (RP) (patient set 1, n = 43, including (GP 3) n = 22, (GP 4) n = 35, and (GP 5) n = 12) and needle biopsy (patient set 2, n = 10, (GP 4) n = 10). Cancer tissues from each GP and adjacent normal counterparts were separately collected using laser-captured microdissection (LCM). Real-time RT-PCR was performed to determine the relative expression of miRNAs, including miR-31-5p, -34c-5p, -96-5p, -182-5p, -183-5p, -205-5p, -221-3p, and -222-3p, which were currently reported to be involved in PC progression.
Results: In radical prostatectomy samples, relative expression of miR-31-5p, miR-34c-5p, and miR-205-5p in any GP was significantly decreased compared to normal counterpart. However, no significant difference was detected among GP 3, GP 4, and GP 5. Meanwhile, in the same GP4, expression of miR-31-5p miR-182-5p, and miR-205-5p in cancer tissues obtained from high grade cancer was significantly higher than those obtained from intermediate grade cancer. Validation study using biopsy samples revealed that the relative expression of miR-182-5p was statistically higher in high grade cancer even in same GP4.
Conclusions: We confirmed the expression of miR-182-5p depended on the cancer grade even in same GP 4. Expression of miRNA associated with Gleason grading system may contribute to more accurate preoperative cancer risk evaluation.
Written by:
Tsuchiyama K, Ito H, Taga M, Naganuma S, Oshinoya Y, Nagano KI, Yokoyama O, Itoh H Are you the author?
Division of Tumor Pathology, Department of Pathological Sciences, Faculty of Medical Sciences, University of Fukui, Fukui, Japan; Division of Urology, Department of Surgery, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
Reference: Prostate. 2012 Nov 26. (Epub ahead of print)
doi: 10.1002/pros.22626
PubMed Abstract
PMID: 23184537
