Detection significance of miR-3662, miR-146a, and miR-1290 in serum exosomes of breast cancer patients.

Abstract

The potential relationship between exosomal microRNAs (miRNAs) and clinical symptoms in breast cancer patients and the expression levels of exosomal miRNAs in patients undergoing surgery and chemotherapy are still unclear. The aim of this study was to explore the correlation among exosomal miRNAs and clinical features and treatment in breast cancer patients. First, exosomes were isolated from the serum of patients with breast cancer and healthy controls. Next, the features of exosomes were identified by transmission electron microscopy, nanoparticle tracking analysis, and Western blot assays. Then, we detected the expression of the top-ranked miRNAs (miR-3662, miR-16-1, miR-146a, miR-1290, and miR-29c) in sixty breast cancer patients and twenty healthy controls using quantitative real-time polymerase chain reaction. The differential expression was measured by the Mann-Whitney U-test. The relative expression of miR-3662, miR-146a, and miR-1290 in serum exosomes was significantly higher in patients than healthy controls. Moreover, significant differences were found in the lymph node metastasis and clinical stage of breast cancer as the miRNA levels changed, but their expression levels in exosomes and sera were not correlated. In addition, exosomal miR-3662, miR-146a, and miR-1290 were shown to be valuable biomarkers to monitor patient condition in the course of surgery and chemotherapy. Exosomal miR-3662, miR-146a, and miR-1290 may have promising predictive value and could be utilized as biomarkers for diagnosis and preventative strategy development.