Overexpression of miR-223 correlates with tumor metastasis and poor prognosis in patients with colorectal cancer.

The purpose of the study was to investigate microRNA-223 (miR-223) expression in colorectal cancer (CRC) and its relationship with tumorigenesis and disease prognosis. Quantitative real-time PCR was used to measure levels of miR-223 in tumor samples and adjacent non-cancerous tissues from 62 patients undergoing radical resection for the treatment of CRC. The associations between miR-223 expression and patient age, sex, as well as clinicopathologic parameters, such as tumor size, differentiation, location, invasion depth, metastasis, tumor-node-metastasis (TNM) stage, and overall patient survival, were analyzed by Mann-Whitney U and Kruskal-Wallis tests. Kaplan-Meier method and Cox proportional hazards regression analyses were performed to estimate the prognostic factors for patient survival prediction. The expression of miR-223 was significantly upregulated in CRC tissues compared with adjacent non-cancerous tissues (P < 0.05). This overexpression was associated with TNM stage and lymph node and distant metastases, (P < 0.05). Moreover, Kaplan-Meier analysis demonstrated that patients with high miR-223 expression had a poorer overall survival (OS) than those with low miR-223 expression (P = 0.002). Univariate analysis revealed a statistically significant correlation between OS and miR-223 level, histology grade, metastasis and TNM stage (P < 0.001). Furthermore, miR-223 levels and histology grade were independently associated with OS (HR 0.204, 95 % CI 0.101-0.415, P < 0.05 and HR 2.252, 95 % CI 1.429-3.546, P < 0.05, respectively). The overexpression of miR-223 may play an important role in the progression of CRC and can be used as an independent factor to determine CRC prognosis.

Limited diagnostic value of microRNAs for detecting colorectal cancer: a meta-analysis.

BACKGROUND: MicroRNAs have been demonstrated to play important roles in the development and progression of colorectal cancer. Several studies utilizing microRNAs as diagnostic biomarkers for colorectal cancer (CRC) have been reported. The aim of this meta-analysis was to comprehensively and quantitatively summarize the diagnostic value of microRNAs for detecting colorectal cancer. METHODS: We searched PubMed, Embase and Cochrane Library for published studies that used microRNAs as biomarkers for the diagnosis of colorectal cancer. Summary estimates for sensitivity, specificity and other measures of accuracy of microRNAs in the diagnosis of colorectal cancer were calculated using the bivariate random effects model. A summary receiver operating characteristic (SROC) curve was also generated to summarize the overall effectiveness of the test. RESULT: Thirteen studies from twelve published articles met the inclusion criteria and were included. The overall sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odd ratio of microRNAs for the diagnosis of colorectal cancer were 0.81 (95%CI: 0.79-0.84), 0.78 (95%CI: 0.75-0.82), 4.14 (95%CI: 2.90- 5.92), 0.24 (95%CI: 0.19-0.30), and 19.2 (95%CI: 11.7-31.5), respectively. The area under the SROC curve was 0.89. CONCLUSIONS: The current evidence suggests that the microRNAs test might not be used alone as a screening tool for CRC. Combining microRNAs testing with other conventional tests such as FOBT may improve the diagnostic accuracy for detecting CRC.