Serum miR-106b upregulation predicts poor prognosis in patients with colorectal cancer.

Colorectal cancer (CRC) is one of most common cancers and a leading cause of cancer-related death around the world. Identification of reliable biomarkers contributes to facilitate disease detection of this malignancy. This study aimed to explore the serum miR-106b expression in CRC and its potential clinical significance. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to measure the miR-106b expression levels in the serum from 122 CRC patients, 40 advanced adenomas and 50 healthy individuals. Serum miR-106b levels were significantly increased in CRC patients compared to healthy controls. Elevated serum miR-106b expression occurred more frequently in CRC patients with lymph node metastasis and distant metastasis. Moreover, receiver operating characteristic (ROC) curve analysis revealed that serum miR-106b could well discriminate CRC patients from healthy controls. In addition, miR-106b levels were greatly reduced in post-operative samples from CRC cases with early clinical stage. Furthermore, increased miR-106b expression was positively correlated with aggressive clinical variables and poor prognosis. Finally, serum miR-106b was identified as an independent prognostic predictor for CRC. Collectively, our findings suggest serum miR-106b might potentially serve as a promising biomarker in the diagnosis and prognosis of CRC.