Publications

Abstract

Background: Knowledge of preanalytical conditions that biospecimens are subjected to is critically important because novel surgical procedures, tissue sampling, handling and storage may impact on biomarker expression or invalidate tissue samples as analytes for some technologies. Methods: We investigated the potential warm ischemia effect of robot assisted laparoscopic prostatectomy (RALP) on RNA quality and gene expression by quantitative real time polymerase chain reaction (qPCR), and on immunoreactive protein expression of selected prostate cancer biomarkers. Sections of tissue microarray of 23 RALP and 22 retropubic radical prostatectomy (RRP) tissues were stained with antibodies to AR and PSA as inter-site controls, and 14 other candidate biomarkers of research interest to three laboratories within the Australian Prostate Cancer BioResource. qPCR was performed for AR, PSA (KLK3), KLK2, KLK4, and HIF1A on RNA extracted from 5 RALP and 5 RRP frozen tissue cores. Results: No histological differences were observed between RALP and RRP tissue. Biomarker staining grouped into those with increased (PSA, CK8/18, CKHMW, KLK4), decreased (KLK2, KLK14) or no change in expression (AR, ghrelin, Ki67, PCNA, VEGF-C, PAR2, YB1, p63, versican, chondroitin 0-sulfate) in RALP compared to RRP tissue. No difference in RNA quality or gene expression was detected between RALP and RRP tissue. Conclusions: Changes in biomarker expression between RALP and RRP tissue may result from procedural differences such as the warm ischemia period in RALP. Impact: Future studies should account for changes in biomarker expression when using RALP tissues, and mixed cohorts of RALP and RRP tissue should be avoided.