Effect of miR-24 on chemotherapy sensitivity in lung cancer A549 cells
10.3969/j.issn.1000-4718.2018.06.014
- VernacularTitle:miR-24对肺癌A549细胞化疗敏感性的影响
- Author:
Shu-Juan SU
1
;
Tao FAN
;
Yi-Chang SUN
;
Jin-Shan REN
Author Information
1. 南阳医学高等专科学校第一附属医院放疗科
- Keywords:
MicroRNA-24;
Lung adenocarcinoma;
Chemotherapy resistance;
Apoptosis;
ERK/P53 signaling pathway
- From:
Chinese Journal of Pathophysiology
2018;34(6):1042-1048
- CountryChina
- Language:Chinese
-
Abstract:
AIM:To study the effect of microRNA (miR)-24 on chemotherapy sensitivity and its possible mechanisms in human lung adenocarcinoma A549 cells. METHODS:The expression of miR-24 in the A549 cells and A549/DDP cells was determined by real-time PCR. Transfection of miR-24 inhibitor was used to down-regulate the miR-24 level in the A549/DDP cells. The viability and apoptosis rate were measured by CCK-8 assay and flow cytometry, respec-tively. The protein levels of Bcl-2, Bax, cleaved caspase-3, cleaved caspase-9, cytochrome C (Cyt C), phosphorylated extracellular signal regulated kinase (p-ERK) and P53 were detected by Western blot. Luciferase reporter assay was used to predict and identify the target genes of miR-24. RESULTS:The expression of miR-24 was significantly higher in the A549/DDP cells than that in the A549 cells (P<0.05). miR-24 inhibitor induced cell apoptosis and increased the sensi-tivity of the A549/DDP cells to cisplatin. Furthermore, miR-24 inhibitor down-regulated the ratio of Bcl-2/Bax, while up-regulated the protein levels of P53, p-ERK, cleaved caspase-9, cleaved caspase-3 and Cyt C. Incubation with U0126, a specific ERK inhibitor, partly reversed the viability of miR-24 inhibitor transfected A549/DDP cells. Bioinformatics analy-sis demonstrated that p53 was a potential target gene of miR-24. Co-teansfection of miR-24 inhibitor and P53 siRNA in A549/DDP cells partially reversed the effect of miR-24 inhibitor on cell viabiltiy. CONCLUSION:Down-regulation of miR-24 increases the sensitivity of A549/DDP cells to cisplatin. The mechanism may be related to directly targeting p53 gene and over-activation of ERK/P53 signaling pathway, thus promoting apoptosis via mitochondrial apoptosis pathway.
