Circulating levels of serum microRNAs (miRNAs) show potential for the timely detection of early-stage ovarian cancer, a recent study has found.
Using droplet digital polymerase chain reaction (ddPCR), researchers measured circulating miRNA levels in serum samples from 105 healthy controls and 72 patients with untreated ovarian cancer (stages I to IV). Samples were divided into discovery/training and clinical validation sets. Forty-five candidate miRNAs were assessed.
Of the 45 candidates, 11 miRNAs were consistently undetected in serum samples of cancer patients and were subsequently removed from analysis. Further comparisons between patients and controls identified six miRNAs with different expression levels. Two were present in higher concentrations cancer patients during both the early and late phases of disease while the remaining four were elevated only in late stages.
Subsequent unadjusted logistic regression analysis found that all six miRNAs were associated with an increased risk of ovarian cancer, with odds ratio [OR] values ranging from 1.5 to 15.1. After multivariate adjustments, only two remained significantly and independently associated with ovarian cancer: miR-320b (OR, 17.7, 95 percent confidence interval [CI], 4.8–64.4) and miR-141-3p (OR, 2.3, 95 percent CI, 1.3–4.0).
The performance of the miRNA markers was tested in an independent cohort, where they showed sensitivity and specificity of 68.0 percent and 70.3 percent, respectively for the prediction of ovarian cancer. The resulting area under the curve (AUC) was 0.723. Notably, the miRNA markers were more useful for the prediction of early-stage ovarian cancer, with sensitivity, specificity, and AUC values of 80.0 percent, 70.3 percent, and 0.789, respectively.
The inclusion of protein classifiers further improved the predictive value of the miRNA markers.