title: MicroRNA-196a overexpression promotes cell proliferation and inhibits cell apoptosis through PTEN/Akt/FOXO1 pathway.
abstract: MicroRNAs (miRNAs) are endogenous, non-coding, small RNAs, which play a critical role in regulating varieties of the biological and pathologic processes. MiR-196a has been reported to take part in tumorigenic progression of osteosarcoma (OS). However, the effects of miR-196a on OS are still unclear. The objective of this study is to investigate the molecular mechanism of miR-196a in osteosarcoma cells. In the present study, the expression of miR-196a in OS cell lines was detected by real-time PCR. We found that the expression level of miR-196a was markedly up-regulated in osteosarcoma cell lines compared with normal osteoblastic cells. Then, the miR-196a mimic was transiently transfected into MG63 and U2OS cells using Lipofectamine™ 2000 reagent. Subsequently, the MTT and Brdu-ELISA results showed that up-regulation of miR-196a promoted the cell viability and proliferation. Our results also showed that miR-196a mimic accelerated cell cycle progression of MG63 and U2OS cells by down regulation of p21 and p27, and upregulation of cyclin D1. In addition, overexpression of miR-196a suppressed apoptosis of MG63 and U2OS cells due to increasing BCL2L2 and MCL-1 expressions, and then inactivating caspase-3. Eventually, the effect of miR-196a mimic on the PTEN/phosphoinositide 3-kinase (PI3K)/Akt signaling pathway was explored by Western blot. From our results, transfection of miR-196a decreased the expression of PTEN and increased the phosphorylation of PI3K and Akt. Taken together, miR-196a should be an oncogene in osteosarcoma. The possible mechanism was that overexpression of miR-196a promoted proliferation of MG63 and U2OS cells by modulating the PTEN/PI3K/Akt signaling pathway.
authors.affiliation: Department of Orthopaedics, Air Force General Hospital of PLA Beijing 100142, People's Republic of China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Shang
authors.affiliation: Department of Chronic Diseases, Haidian Center For Disease Control and Prevention Beijing 100142, People's Republic of China.
authors.forename: Li-Qing
authors.initials: LQ
authors.lastname: Wang
authors.affiliation: Institute of Orthopaedics, Chinese PLA General Hospital Beijing 100142, People's Republic of China.
authors.forename: Quan-Yi
authors.initials: QY
authors.lastname: Guo
authors.affiliation: Department of Orthopaedics, Air Force General Hospital of PLA Beijing 100142, People's Republic of China.
authors.forename: Tu-Long
authors.initials: TL
authors.lastname: Shi
mesh_terms: D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D001859:Bone Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D018797:Cell Cycle Proteins / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D012516:Osteosarcoma / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D051059:PTEN Phosphohydrolase / Q000378:metabolism*; D058539:Phosphatidylinositol 3-Kinase / Q000378:metabolism; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D014162:Transfection; D015854:Up-Regulation
chemical_list: D051017:Apoptosis Regulatory Proteins; D018797:Cell Cycle Proteins; C085126:FOXO1 protein, human; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors; C542543:MIRN196 microRNA, human; D035683:MicroRNAs; D058539:Phosphatidylinositol 3-Kinase; D051057:Proto-Oncogene Proteins c-akt; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human
keywords: MicroRNA-196a; PTEN/PI3K/Akt signaling pathway; apoptosis; cell cycle; osteosarcoma; proliferation