MicroRNA-28 promotes the proliferation of non-small-cell lung cancer cells by targeting PTEN

Non-small-cell lung cancer (NSCLC) is the fundamental form of lung cancer and the leading cause of cancer-related mortality in humans. Numerous studies have identified a role for microRNAs (miRs) in cell proliferation, invasion and metastasis in numerous types of cancer, including lung cancer. In the present study, the functional roles and molecular mechanisms of miR-28 in NSCLC tumorigenesis were investigated. Reverse transcription-quantitative PCR (RT-qPCR) was used to measure miR-28 expression levels in NSCLC tumor tissues and cell lines. A dual-luciferase assay was performed to observe the direct interaction between miR-28 and PTEN in A549 cells. Furthermore, the effect of miR-28 on the mRNA and protein expression levels of PTEN was examined by RT-qPCR and western blotting, respectively. A Cell Counting kit-8 assay was performed to identify the relationship between the miR-28/PTEN axis and tumor cell proliferation using cells infected with lentivirus (LV)-anti-miR-28 or LV-anti-miR-28 + short hairpin RNA-PTEN. miR-28 expression was upregulated in NSCLC tumor tissues and cell lines compared with the control groups. PTEN was identified as the downstream gene of miR-28 in NSCLC and was negatively regulated by miR-28. In addition, miR-28 knockdown suppressed the proliferation of A549 and H292 cells. Cells infected with LV-anti-miR-28 + short hairpin RNA-PTEN promoted tumor cell proliferation in A549 and H292 cells compared with cells infected with LV-anti-miR-28. Taken together, the present study suggested that miR-28 might serve as the promoter in the development of NSCLC by targeting PTEN. Therefore, the miR-28/PTEN axis may serve as a potential diagnostic and therapeutic target for NSCLC.