Integrative analysis of microRNA and mRNA expression profiles in non-small-cell lung cancer.

Non-small-cell lung cancer (NSCLC) represents the most common deadly disease. Emerging evidences suggest that abnormal epigenetic modulation via mRNAs and microRNAs (miRNAs) might be involved in the tumorigenesis. To explore novel therapeutic target of NSCLC, a more detailed mRNAs and miRNA expression profiling study is needed. High-quality total RNA including miRNA was isolated from NSCLC tissue and para-carcinoma tissue and used for RNA and small RNA sequencing. Results were analyzed bioinformatically and validated using quantitative real-time (qRT)-PCR. A total of 3530 genes (1977 up-regulated and 1553 down-regulated) and 211 miRNAs (171 up-regulated and 30 down-regulated) were differentially expressed (DE) in NSCLC tissue versus adjacent normal tissues. Furthermore, 157 novel miRNAs were predicted in our samples. Of these, 918 significant miRNA-mRNA pairs were identified, consisting of 100 miRNAs and 443 mRNAs. Gene ontology analysis revealed that most of the target genes were enriched in the terms of plasma membrane, binding, and multiple biological-molecular signaling processes. Pathway analysis of these miRNA signatures highlights their critical roles in calcium signaling pathway. Using qRT-PCR, the expression of several DE genes (KRAS and RBM5) and miRNAs (miR-1-5p, let-7b-5p, miR-21-5p, miR-1290, miR-149-5p, chr8_28846, chrX_31594, and chr9_29897) were confirmed. The integrative analysis based on mRNA and miRNA profiling may provide more potential molecular for the tumorigenesis and development of NSCLC.