ABSTRACT
OBJECTIVE: To explore the role of microRNA-217 in non-small cell lung cancer (NSCLC) and its underlying mechanism. PATIENTS AND METHODS: MicroRNA-217 expression in 48 NSCLC tissues and paracancerous tissues were detected by qRT-PCR (quantitative Real-time polymerase chain reaction). The relationship between microRNA-217 expression and prognosis of NSCLC patients was analyzed. Target gene of microRNA-217 was predicted by bioinformatics method and further verified by luciferase reporter gene assay. Cell proliferation, cell cycle and apoptosis were detected after altering microRNA-217 expression in NSCLC cells. The effect of microRNA-217 on regulating PI3K pathway was detected by Western blot. RESULTS: MicroRNA-217 was downregulated in NSCLC tissues than that of paracancerous tissues. Shorter overall survival (OS) was observed in NSCLC patients with lower expression of microRNA-217 than those with higher expression. Overexpressed microRNA-217 remarkably inhibited proliferation and cell cycle, whereas induced apoptosis of NSCLC cells. AKT3 was screened out to be the target gene of microRNA-217. Western blot results demonstrated that microRNA-217 upregulated AKT3 and PI3K pathway-related genes. CONCLUSIONS: Downregulated microRNA-217 promotes the occurrence and progression of NSCLC through upregulating AKT3 via PI3K pathway.
Subject(s)
Carcinoma, Non-Small-Cell Lung/genetics , Lung Neoplasms/genetics , MicroRNAs/genetics , Proto-Oncogene Proteins c-akt/genetics , Signal Transduction , 3' Untranslated Regions , A549 Cells , Cell Cycle , Cell Line, Tumor , Cell Movement , Cell Proliferation , Cell Survival , Down-Regulation , Gene Expression Regulation, Neoplastic , Humans , Proto-Oncogene Proteins c-akt/metabolism , Survival AnalysisABSTRACT
The ATP-binding cassette (ABC) transporters belong to a large superfamily of proteins that have important physiological functions in all living organisms. In insects, ABC transporters have important functions in the transport of molecules, and are also involved in insecticide resistance, metabolism, and development. In this study, the Nilaparvata lugens Stal (Hemiptera: Delphacidae) ABCG (NlABCG) gene was identified and characterized. The complete mRNA sequence of NlABCG was 2608-bp long, with an open reading frame of 2064 bp encoding a protein comprised of 687 amino acids. The conserved regions include three N-glycosylation and 34 phosphorylation sites, as well as seven transmembrane domains. The amino acid identity with the closely related species Acyrthosiphon pisum was 42.8%. Developmental expression analysis using quantitative real-time reverse transcriptase PCR suggested that the NlABCG transcript was expressed at all developmental stages of N. lugens. The lowest expression of NlABCG was in the 1st instar, and levels increased with larval growth. The transcript profiles of NlABCG were analyzed in various tissues from a 5th instar nymph, and the highest expression was observed in the midgut. These results suggest that the sequence, characteristics, and expression of NlABCG are highly conserved, and basic information is provided for its functional analysis.
