Expression levels and co­targets of miRNA­126­3p and miRNA­126­5p in lung adenocarcinoma tissues: Αn exploration with RT­qPCR, microarray and bioinformatic analyses.

Lung adenocarcinoma (LUAD) is the most common histological subtype of lung cancer. Previous studies have found that many microRNAs (miRNAs), including miRNA­126­3p, may play a critical role in the development of LUAD. However, no study of LUAD has researched the synergistic effects and co­targets of both miRNA­126­3p and miRNA­126­5p. The present study used real­time quantitative polymerase chain reaction (RT­qPCR) to explore the expression values of miRNA­126­3p and miRNA­126­5p in 101 LUAD and 101 normal lung tissues. Ten relevant microarray datasets were screened to further validate the expression levels of miRNA­126­3p and ­5p in LUAD. Twelve prediction tools were employed to obtain potential targets of miRNA­126­3p and miRNA­126­5p. The results showed that both miRNA­126­3p and ­5p were expressed significantly lower in LUAD. A significant positive correlation was also present between miRNA­126­3p and ­5p expression in LUAD. In addition, lower expression of miRNA­126­3p and ­5p was indicative of vascular invasion, lymph node metastasis (LNM), and a later tumor/node/metastasis (TNM) stage of LUAD. The authors obtained 167 targets of miRNA­126­3p and 212 targets of miRNA­126­5p; 44 targets were co­targets of both. Eight co­target genes (IGF2BP1, TRPM8, DUSP4, SOX11, PLOD2, LIN28A, LIN28B and SLC7A11) were initially identified as key genes in LUAD. The results of the present study indicated that the co­regulation of miRNA­126­3p and miRNA­126­5p plays a key role in the development of LUAD, which also suggests a fail­proof mode between miRNA­3p and miRNA­126­5p.