Serum expression levels of miR-17, miR-21, and miR-92 as potential biomarkers for recurrence after adjuvant chemotherapy in colon cancer patients

The present study examined whether miR-17, miR-21, miR-29a, and miR-92 that are dysregulated in colon cancer (CC) can serve as potential predictive markers for relapse of disease after radical surgery and adjuvant chemotherapy. Real-time reverse transcription quantitative polymerase chain reaction was used to measure the expression levels of the miRNAs in serum samples from 37 patients with CC and 7 healthy individuals, tested as a control group. The area under the receiver operating characteristic curve (AUC) was then used to evaluate the predictive performance of the four miRNAs alone or in combination and compare it with carcinoembryonic antigen. The expression of miR-17, miR-21 and miR-92 were significantly higher in serum of patients with disease relapse. The AUCs for miR-17, miR-21, miR-92 for Nx patients were 0.844, 0.948, and 0.935, respectively (p < 0.05). Combining the four miRNAs for stage III patients increased the diagnostic performance, yielding an AUC of 0.881, with a sensitivity of 83.3% and a specificity of 85.7% (p < 0.05). Our study suggests that the expression levels of serum miR-21, miR-17, and miR-92 in patients with CC who underwent radical surgery and adjuvant chemotherapy may have diagnostic value for differentiating between recurred and non-recurred patients.