miR-133 involves in lung adenocarcinoma cell metastasis by targeting FLOT2

Dysregulated microRNAs (miRNAs) reported to involve into the oncogenesis and progression in various human cancers. However, the roles and mechanism of miR-133 in lung adenocarcinoma remain largely unclear.

In this study, qPCR assay and western blot were used to detect the expression levels of miR-133, Akt and FLOT2. Luciferase reporter assay was used to identify the target role of miR-133 on FLOT2. The cell invasion and the migration capability were performed using the transwell invasion assay and wound healing assay.

We found that miR-133 expression levels were downregulated in human lung adenocarcinoma specimens and cell lines compared with the adjacent normal tissues and normal human bronchial epithelial cell. miR-133 significantly suppressed metastasis of lung adenocarcinoma cells in vitro. Furthermore, FLOT2 (flotillin-2) identified as a direct target of miR-133, and FLOT2 expression levels were inversely correlated with miR-133 expression levels in human lung adenocarcinoma specimens. And the restoration studies suggested FGF2 as a downstream effector of miR-133 which acted through Akt signalling pathway.

Our study revealed the mechanism that miR-133 suppresses lung adenocarcinoma metastasis by targeting FLOT2 via Akt signalling pathway, implicating a potential prognostic biomarker and therapeutic target for lung adenocarcinoma treatment.