Stool-Based miR-92a and miR-144∗ as noninvasive biomarkers for colorectal cancer screening

Objectives: Current noninvasive screening tests for colorectal cancer (CRC) have insufficient sensitivity. MicroRNA (miRNA) levels in stool have potential as markers for noninvasive screening of CRC. We evaluated the diagnostic value of stool miRNA levels and determined the optimal miRNA subtypes for detecting CRC. Methods: Stool samples were collected from 29 patients with CRC and 29 healthy controls. The stool levels of miR-21, miR-92a, miR-200c, miR-144∗, miR-135a, miR-135b, miR-106a, and miR-17-3p were determined by real-time quantitative reverse transcription polymerase chain reaction. The sensitivity and specificity of the miRNAs for CRC were determined by receiver operating characteristics analysis. Results: Among the eight tested miRNAs, the mean stool levels of miR-21, miR-92a, miR-144∗, and miR-17-3p differed significantly between the CRC group and the control group (p =0.014, 0.001, <0.001, and 0.008, respectively). The sensitivities and specificities of miR-21, miR-92, miR-144∗, and miR-17-3p were 79.3 and 48.3%, 89.7 and 51.7%, 78.6 and 66.7%, and 67.9 and 70.8%, respectively. In a multivariate analysis, miR-92a and miR-144∗ were significantly associated with the presence of CRC (p = 0.03 and 0.011, respectively). Conclusions: The stool levels of miR-92a and miR-144∗ showed good sensitivity and fair specificity for detection of CRC, and thus may be useful as noninvasive biomarkers for this disease.