microRNA-20a in human faeces as a non-invasive biomarker for colorectal cancer

// Tung On Yau 1 , Chung Wah Wu 1 , Ceen-Ming Tang 1, 2 , Yingxuan Chen 3 , Jingyuan Fang 3 , Yujuan Dong 1, 4 , Qiaoyi Liang 1 , Simon Siu Man Ng 4 , Francis Ka Leung Chan 1 , Joseph Jao Yiu Sung 1 , Jun Yu 1 1 Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, CUHK Shenzhen Research Institute, The Chinese University of Hong Kong, Hong Kong 2 Oxford University Clinical Academic Graduate School, John Radcliffe Hospital, Oxford, UK 3 Renji Hospital, Shanghai Jiaotong University, Shanghai, China 4 Department of Surgery, The Chinese University of Hong Kong, Hong Kong Correspondence to: Jun Yu, e-mail: junyu@cuhk.edu.hk Keywords: microRNA, non-invasive, stool biomarker, colorectal cancer, diagnosis Received: July 25, 2015      Accepted: November 15, 2015      Published: November 26, 2015 ABSTRACT Objective: Detection of microRNA (miRNA) aberrations in human faeces is a new approach for colorectal cancer (CRC) screening. The aim of this study was to characterise miR-20a in faeces as a non-invasive biomarker for diagnosis of CRC. Results: miR-20a expression was significantly higher in the 40 CRC tumours compared to their respective adjacent normal tissues ( P = 0.0065). Levels of miR-20a were also significantly higher in faecal samples from CRC patients ( P < 0.0001). The area under receiver operating characteristic (AUROC) curve for miR-20a was 0.73, with a sensitivity of 55% and specificity of 82% for CRC patients compared with controls. No significant difference in the level of miR-20a was found between patients with proximal, distal, and rectal cancer. The use of antibiotics did not influence faecal miR-20a levels. Patients and Methods: miR-20a was selected from an expression microarray containing 667 miRNAs. Further verification of miR-20a was performed in 40 pairs of primary CRC tissues, as well as 595 faecal samples (198 CRCs, 199 adenomas, and 198 healthy controls) using TaqMan probe based quantitative Real-Time PCR (qRT-PCR). Conclusions: Faecal-based miR-20a can be utilised as a potential non-invasive biomarker for CRC screening.