대장암 선별검사를 위한 비침습적 바이오마커로서 대변 마이크로 RNA-221과 Let-7a의 유용성

Abstract

Abstract Background and Aims: Fecal microRNA (miRNA) identification has been expected a non-invasive biomarker test for colorectal cancer (CRC) screening. The purpose of this study was to investigate fecal miRNAs which are altered in colorectal neoplasia. We also aimed to find out the combination of fecal miRNAs for improved performance in CRC screening. Methods: We collected a total of 97 stool samples from 30 patients with CRCs, 35 patients with colorectal adenomas, and 32 healthy controls. We investigated the expression of 13 fecal miRNAs (miR-17, -21, -27a, -92, -106a, -145, -155, -181b, -199a, -200c, -221, -494, Let-7a) and compared their expression between CRC, colorectal adenoma, and healthy control groups. Results: In univariate analysis, age, fecal miR-21, -145, -155, -199a, -221, -494 and Let-7a showed significant differences between the neoplastic group and healthy control. In logistic regression, age (Odds ratio (OR) 21.1, 95% confidence interval (CI) 2.2-151.7, p=0.005), miR-221 (OR 4.1, 95% CI 1.1-16.5, p=0.037) and Let-7a (OR 11.7, 95% CI 1.3-103.6, p=0.034) were identified as independent risk factors for colorectal neoplasia. The area under the curve (AUC) of age, fecal miR-221, and Let-7a were 0.656 (95% CI, 0.552-0.750), 0.742 (95% CI, 0.643-0.827) and 0.645 (95% CI, 0.540-0.740) for the neoplastic group, respectively. The AUC of the combination of age, fecal miR-221 and Let-7a was higher than that of each variable (0.839; 95% CI, 0.749-0.907). The combination of fecal miRNAs and age showed high sensitivity (79.4%) and specificity (86.7%) for diagnosis of colorectal neoplasia. Conclusion: Fecal miR-221 and Let-7a may be useful non-invasive biomarkers for CRC screening. The combination of these two fecal miRNAs with age can predict the presence of CRCs and colorectal adenomas with high confidence.