RESUMO
Non-small cell lung cancer (NSCLC) causes high mortality worldwide; however, its molecular pathways have not been fully investigated. The relationship between FOXA1 and CDC5L as well as their roles in NSCLC have not been comprehensively studied. Clinical tissues were collected from 78 NSCLC patients for clinical studies. The BEAS-2B human normal lung epithelial cell line and the A549, Calu-3, H526 and H2170 human NSCLC cell lines were used for in vitro studies. sh-FOXA1 and oe-CDC5L constructs were used to generate knockdown and overexpression models, respectively. The CCK-8 assay was used to analyze cell viability. The cell cycle and apoptosis were evaluated by flow cytometry analysis. The relationship between FOXA1 and CDC5L was demonstrated using dual-luciferase and ChIP assays. Gene levels were examined via immunohistochemistry, qRT-PCR and western blot analysis. FOXA1 levels were increased in NSCLC clinical tissues and cell lines. Depletion of FOXA1 increased the apoptosis rate and increased the proportion of cells in G2/M phase. In addition, we demonstrated that FOXA1 was directly bound to the promoter of CDC5L and that depletion of FOXA1 inhibited CDC5L expression. Overexpression of CDC5L induced ERK1/2 phosphorylation, induced JAK2 phosphorylation, inhibited cell apoptosis, prolonged S phase, and significantly reversed the effects of FOXA1 knockdown on the progression of NSCLC. The present study demonstrated that FOXA1 prolongs S phase and promotes NSCLC progression through upregulation of CDC5L and activation of the ERK1/2 and JAK2 pathways.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Regulação para Cima/genética , Fase S , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Apoptose/genética , MicroRNAs/genética , Linhagem Celular Tumoral , Movimento Celular , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Janus Quinase 2/genética , Janus Quinase 2/metabolismoRESUMO
Aims: We aim to investigate the effects of miR-421 on lipid metabolism in non-small cell lung cancer (NSCLC). Methods: The miR-421 expression and PTEN mRNA level in tumor tissues, adjacent normal tissues, human lung epithelial cells and NSCLC cell lines were detected with reverse transcription quantitative real-time PCR. Results: MiR-421 was increased, and PTEN was reduced remarkably in tumor tissues and NSCLC cell lines. Down-regulated miR-421 suppressed lipid accumulation, cell proliferation, migration and invasion, whereas overexpression of miR-421 had the opposite effects. MiR-421 directly targeted PTEN and negatively regulated PTEN expression. MiR-421 activated PI3K/AKT/mTOR pathway through regulating PTEN. Conclusion: MiR-421 promotes lipid metabolism through targeting PTEN via PI3K/AKT/mTOR pathway activation in NSCLC, indicating that miR-421 can be a latent therapeutic target for NSCLC.
Lay abstract Numerous miRNAs are dysregulated in lung cancer, which play vital roles in tumor progression. Currently, the alteration of lipid metabolism has been recognized as a critical hallmark of cancer. In the present study, we found that miR-421 targeted PTEN to promote lipid metabolism via activation of PI3K/AKT/mTOR signaling pathway in NSCLC. This study might provide a deeper insight into the prognostics strategies for lung cancer by understanding the specific mechanism of miR-421 in lipid metabolism.