Abstract
Background: Early breast cancer is a frequent female disease with different outcomes. New approaches are needed in order to improve its prognosis.
MicroRNAs (miRs) are modulators of gene expression and act as oncogenes and function to inhibit tumor suppressors and to promote metastasizing. Monitoring of miRs could be of benefit to the prognosis of EBC patients.
Results: EBC patients significantly over-express miRs in time point I. In time point II the levels of miR-155, miR-181b, miR-24 significantly decreased (p 0.05).
Triple-negativity, HER2+, grade III, LN+ have no effect on the probability of relapse (p> 0.05) when miRs are simultaneously taken into an account. The only risk factor that makes the prediction of relapse more precise is Ki-67 > 20\% (p= 0.013 in case of miR-155 and p= 0.023 in case of miR-24).
Conclusions: OncomiRs are significantly more abundant in EBC patients at diagnosis and decline after therapy. Differences in miR levels reflect EBC risk groups.
The data shows that miR-155 and miR-24 enable monitoring of EBC and predict relapse independently of clinical/pathological risk factors. Combining the miR levels with Ki-67 expression further specifies the relapse probability.