RESUMO
Background: Colorectal cancer (CRC) is one of the most common cancers worldwide. Although colonoscopy is considered as the "Gold Standard" technique to detect CRC, its application is invasive and cost incurred. Thus, noninvasive or minimally invasive approaches are of utmost importance. The aberrant expression of some microRNAs (miRNAs, miRs) has been suggested in association with CRC pathogenesis. This study aimed to validate if circulating serum miR-1229 and miR-1246 are diagnostic biomarkers for CRC. Materials and Methods: Serum samples were isolated from 45 CRC patients and also 45 healthy controls (HC). The expression levels of circulating serum-derived miR-1229 and miR-1246 were evaluated by quantitative real-time polymerase chain reaction. Receiver operating characteristic (ROC) curves were constructed to evaluate the CRC diagnostic accuracy of selected miRNAs. Furthermore, the association of candidate miRNAs and clinicopathological characteristics were evaluated. Functional enrichment of the candidate miRNAs was applied using in silico tools. Results: The expression of miR-1229 and miR-1246 was significantly higher in CRC patients than HC (P < 0.0001) and also was found in association with lymph node metastasis (P < 0.05). We demonstrated a significant up-regulation of serum-derived miR-1246 in advanced tumor-node-metastasis stage III of CRC patients (P < 0.05). Areas under the ROC curve of miR-1229 and miR-1246 were 0.81 and 0.84, respectively (P < 0.0001). Conclusion: We confirmed the capability of circulating serum miR-1229 and miR-1246 as novel diagnostic biomarkers for CRC.