Upregulation of serum miR-103 predicts unfavorable prognosis in patients with colorectal cancer

OBJECTIVE: Circulating microRNAs (miRNAs) have been reported as biomarkers for the early detection of colorectal cancer (CRC). We aimed at evaluating the diagnostic and prognostic value of serum miR-103 in CRC patients. PATIENTS AND METHODS: Quantitative reverse-transcription PCR (qRT-PCR) was applied to measure the miR-103 levels in blood samples of 96 patients and 60 controls. RESULTS: Our results demonstrated that serum miR-103 was overexpressed in CRC subjects and the receiver operating characteristic (ROC) curve analysis showed that serum miR-103 could differentiate CRC cases from controls with relatively high accuracy. In addition, serum miR103 level was more frequently detected in CRC patients with positive lymph node metastasis, distant metastasis and advanced tumor stage. Moreover, serum miR-103 levels in 23 postoperative blood samples were lower than paired preoperative plasma specimens, and serum miR103 levels were re-elevated in seven patients at recurrence. Furthermore, serum miR-103 was significantly correlated with worse clinical factors, as well as poorer recurrence-free survival or overall survival. Finally, multivariate analysis confirmed that serum miR-103 was an independent prognostic marker for CRC. CONCLUSIONS: Taken together, serum miR103 might be a promising biomarker for diagnosis and prognosis of CRC.