MiR-424 Promotes Non-Small Cell Lung Cancer Progression and Metastasis through Regulating the Tumor Suppressor Gene TNFAIP1.

BACKGROUND/AIMS: This study aimed to investigate the potential roles of miR-424 expression in non-small cell lung cancer (NSCLC) metastasis and growth and its underlying mechanism.

METHODS: The expression of miR-424 in two NSCLC cell lines (A549 and H1975) was altered by transfection with miR-424 mimic and inhibitor. Effects of miR-424 overexpression and suppression on cells migration, invasion and colony formation were analyzed. Target genes for miR-424 were predicted using bioinformatics method and then verified using luciferase assay. Effects of miR-424 expression on cell migration, invasion and proliferation were reanalyzed on the condition of TNFAIP1 was silenced. Moreover, TNFAIP1 silencing and miR-424 modified A549 cells were subcutaneous injected into node BALB/c mice to confirm the regulation of miR-424 on TNFAIP1 in regulating tumor growth.

RESULTS: Compared with the control, miR-424 overexpression significantly increased the migrated and invaded cells, as well as the proliferated colonies. TNFAIP1 was a predicted target gene for miR-424, and was negatively regulated by miR-424. TNFAIP1 silence significantly increased the migrated and invaded cells compared to that in control, while these increases were abolished by miR-424 suppression. Animal experiment further evidenced miR-424 affected tumor growth by regulating TNFAIP1.

CONCLUSIONS: These data demonstrate that miR-424 may be a contributor for NSCLC progression and metastasis through involving in cell migration, invasion and proliferation via inhibiting TNFAIP1. This study may provide theoretical basis for miR-424 in NSCLC target therapeutic treatment.