Bo-chuan Lin, Dong Huang, Chao-qun Yu, Yong Mou, Yuan-hang Liu, Da-wei Zhang, Feng-jun Shi
(The Third Clinical College, Southern Medical University, Department of Traumatology and Microsurgery, Second People’s Hospital of Guangdong Province, The Third Clinical College, Southern Medical University, Guangzhou, Guangdong, China (mainland))
Med Sci Monit 2016; 22:1761-1765
Early metastasis of osteosarcoma (OS) is highly lethal and responds poorly to drug and radiation therapies. MicroRNAs (miRNAs) are a class of small noncoding RNAs that modulate gene expression at the post-transcriptional level. However, the detailed functions of specific miRNAs are not entirely understood. The aim of the present study was to investigate the role of miR-184 as a mediator of drug resistance in human osteosarcoma.
MATERIAL AND METHODS: qRT-PCR was used to analyze the expression level of miR-184 in OS cell line U-2 OS and MG-63 treated with doxorubicin. MiR-184 agomir or miR-184 antagomir was transferred into cells to regulated miR-184. The target of miR-184 was predicted by TargetScan and confirmed by luciferase reporter assay. Bcl-2-like protein 1 (BCL2L1) expression was detected by Western blot. Cell apoptosis was determined by Annexin V staining and analysis by flow cytometry.
RESULTS: Doxorubicin induced time-dependent expression of miR-184 in OS cell line U-2 OS and MG-63. Luciferase reporter assay identiﬁed BCL2L1 as the direct target gene of miR-184. Furthermore, doxorubicin reduced BCL2L1 expression, which was reversed by miR-184 overexpression and further decreased by miR-184 inhibition in OS cells. In addition, miR-184 agomir reduced doxorubicin-induced cell apoptosis, whereas miR-184 antagomir enhanced apoptosis in OS cells, suggesting that up-regulation of miR-184 contributes to chemoresistance of the OS cell line.
CONCLUSIONS: Our data show that miR-184 was up-regulated in OS patients treated with doxorubicin therapy and leads to poor response to drug therapy by targeting BCL2L1.
Keywords: 3' Untranslated Regions, Antibiotics, Antineoplastic - pharmacology, Apoptosis - drug effects, Bone Neoplasms - pathology, Cell Line, Tumor, Cell Proliferation - drug effects, Doxorubicin - pharmacology, Drug Resistance, Neoplasm - genetics, Humans, MicroRNAs - metabolism, Osteosarcoma - pathology, bcl-X Protein - metabolism