Wu D, Chen B, Cui F, He X, Wang W, Wang M. Hypoxia-induced microRNA-301b regulates apoptosis by targeting Bim in lung cancer.
Cell Prolif 2016;
49:476-83. [PMID:
27352910 PMCID:
PMC6495957 DOI:
10.1111/cpr.12264]
[Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 04/27/2016] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVES
Worldwide, lung cancer accounts for the majority of cancer-related deaths. Aberrant expression of miRNAs has increasingly been reported to be associated with tumour progression. This study aimed to explore the role of miR-301b in regulating apoptosis in lung cancer.
MATERIALS AND METHODS
Expression of miR-301b was assessed by real-time PCR in cell lines, human patient tissues and cells treated under hypoxia and DMOG. Scramble siRNA, miR-301b inhibitor and miR-301b mimics were transfected into lung cancer cells to determine their effects on apoptosis. Additionally, a mouse xenograft model was used to explore functions of miR-301b on apoptosis, in vivo. Finally, relationships between Bim and miR-301b levels were explored by luciferase reporter assay and Western blotting.
RESULTS
We found that miR-301b was highly expressed in lung cancer tissues and cell lines. Expression of miR-301b was induced by hypoxia, and miR-301b suppressed expression of Bim by targeting its 3'UTR. Functionally, ectopic expression of miR-301b enhanced cell population growth, reduced apoptosis and reduced sensitivity of cells to chemotherapy. In the xenograft model, overexpression of miR-301b promoted tumour growth. Additionally, miR-301b and Bim expression were inversely correlated in clinical lung cancer samples.
CONCLUSIONS
This study provides new insights into the function of miRNA-301b in lung cancer and suggests that miRNA-301b could be a potential molecular target for chemotherapy.
Collapse