miR-21, miR-221 and miR-150 Are Deregulated in Peripheral Blood of Patients with Colorectal Cancer

The Aim of this study was to evaluate the expression levels of miR-21, miR-221, miR-150, let-7a and miR-126a in peripheral blood of 71 patients with colorectal cancer and 80 matched healthy control individuals. We determined expression levels of these microRNAs in peripheral blood samples and used small nucleolar RNA (RNU48) as an internal control. Expression levels of miR-21 (p<0.0001) and miR-221 (p<0.0001) were significantly higher, whereas expression levels of miR-150 (p=0.0054) were significantly lower in the blood samples of patients with colorectal cancer in comparison to the control group. The combination of these three microRNAs enabled us to distinguish patients with colorectal cancer from healthy donors with a sensitivity of 80% and specificity of 74% (p<0.0001). We did not observe any correlation of the studied microRNAs with clinicopathological features of colorectal cancer, indicating that expression of these microRNAs is more likely related to the host response to the tumour than the tumour itself.