Novel circulating microRNAs expression profile in colon cancer: a pilot study

Purpose: To identify the expression profile of novel microRNAs (miRNAs) in colon cancer and evaluate their clinical applicability. Methods: Differences in the expression of serum miRNAs in patients with colon cancer and healthy controls were identified using miRNA microarrays. Differentially expressed miRNAs were verified via real-time polymerase chain reaction (PCR) using sera from 50 patients with colon cancer and 44 healthy controls. These miRNAs were also verified in a double-blind validation experiment using sera from 30 patients with colon cancer, 30 patients with colonic polyps, and 30 healthy controls. Results: Microarray hybridization revealed that 87 miRNAs were differentially expressed between the sera of patients with colon cancer and healthy controls. Among these miRNAs, 39 miRNAs were up-regulated, whereas 48 miRNAs were down-regulated. Verification of the expression of these miRNAs using real-time PCR revealed that the expression levels of miR-31, miR-141, miR-224-3p, miR-576-5p, and miR-4669 were significantly different between patients with colon cancer and healthy controls. Using these five miRNAs to construct a miRNA expression profile (or miRNA panel) will facilitate more effective diagnosis of colon cancer. Conclusion: Clinical analysis of miR-31, miR-141, miR-224-3p, miR-576-5p, and miR-4669 expression in patients with colon cancer may facilitate the diagnosis of colon cancer.