Abstract
BACKGROUND: Colorectal cancer (CRC) is one of the most prevalent cancers and microRNAs are involved in colorectal carcinogenesis and progression. The role of our candidate microRNAs (miR-143-3p, -424-5p, -212-3p and -34a-3p) have been investigated in various cancers. OBJECTIVE: The aim of the current study was to evaluate expression levels of microRNAs (miR-143-3p, -424-5p, -212-3p and -34a-3p) in the sera of patients with CRC in order to identify potential non-invasive biomarker for CRC and investigate the relationship between their expression and clinicopathological features of CRC. METHODS: The serological expression of candidate microRNAs were measured in 124 participants, including 62 CRC patients and 62 healthy controls and the serum expression levels of candidate miRNAs were quantified by stemloop reverse transcriptionquantitative polymerase chain reaction. RESULTS: In the present study, results showed a significant upregulation expression level of miR-424-5p (P< 0.001) and decreased expression level of miR143-3p was observed in the sera of patients with CRC (P< 0.001). Receiver operating characteristic (ROC) curve analysis demonstrated the area of miR-424-5p and miR-143-3p under the ROC curve for CRC diagnosis were 0.703 and 0.724 respectively (P< 0.001). In addition, down expression of miR-143-3p was significantly associated with tumor size (P= 0.005) and lymph node metastasis (P= 0.020) in CRC patients. CONCLUSIONS: The present investigation suggested that low expression of miR-143-3p and increasing level of miR-424-5p in CRC patients may play an important role in development of CRC and they could function as potential non-invasive biomarkers for CRC.