Circulating Exosomal miRNA Profiles in Non-Small Cell Lung Cancers

A growing number of studies have shown that microRNAs (miRNAs) can exert oncogenic or tumor suppressor activities in a variety of cancers, including lung cancer. Given their presence in exosome preparations, microRNA molecules may in fact participate in exosomal intercellular transfers and signaling. In the present study, we examined the profile of 25 circulating exosomal microRNAs in ostensibly healthy controls compared to patients with squamous cell lung cancers (SQCLC) or lung adenocarcinomas (LUAD). Eight miRNAs, namely, miR-21-5p, miR-126-3p, miR-210-3p, miR-221-3p, Let-7b-5p, miR-146a-5p, miR-222-3p, and miR-9-5p, were highly enriched in the cohort and selected for further analyses. All miRNAs were readily detected in non-small cell lung cancer (NSCLC) patients of both sexes at all cancer stages, and their levels in exosomes correlated with the clinicopathological characteristics of tumors. Thus, the presence of these miRNAs in circulating exosomes may contribute to the regulation of oncogenic activity in patients with NSCLC.