title: MicroRNA sponge blocks the tumor-suppressing functions of microRNA-122 in human hepatoma and osteosarcoma cells.
abstract: MicroRNAs (miRNAs), as gene expression regulators, have been identified to be closely associated with tumorigenesis. Thus a loss-of-function study is more likely to reveal the biological roles of endogenous miRNAs. Genetic knockout, antisense oligonucleotide inhibitors, and miRNA sponge (miR‑SP) are usually performed to inhibit the activities of miRNAs of interest. In the present study, we utilized the miR-SP method, which has long-term rather than short-term effects of antisense oligonucleotide inhibitors, to generate a microRNA-122 sponge (miR-122-SP) mediated by lentivirus, and identified its silencing role in the Huh7 hepatoma cell line and U2OS osteosarcoma cell line. The results showed that miR-122-SP effectively sequestered ectopic miR-122 and restored the expression of miR-122 which targets cyclin G1 (CCNG1), Bcl-w and disintegrin and metalloprotease 10. Moreover, miR-122-SP overexpression rescued the effects of ectopic miR-122 on suppressing proliferation, inhibiting cell migration and invasion, arresting cell cycle at G1 phase, and activating caspase-3/7, not only in Huh7 human hepatoma cells, but also in U2OS osteosarcoma cells. miR-122-SP also knocked down endogenous miR-122 expression in Huh7 and promoted tumorigenesis in vivo. miR-122-SP therefore is a useful tool that may be utilized to study the functions of miR-122 with regard to liver development and tumorigenesis in vitro and in vivo.
authors.affiliation: Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai 200072, P.R. China.
authors.forename: Ji
authors.initials: J
authors.lastname: Ma
authors.affiliation: Department of Medical Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai 200072, P.R. China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wu
authors.affiliation: Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai 200072, P.R. China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai 200072, P.R. China.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Li
authors.affiliation: Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai 200072, P.R. China.
authors.forename: Yongchun
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai 200072, P.R. China.
authors.forename: Qiuhui
authors.initials: Q
authors.lastname: Pan
authors.affiliation: Department of Medical Laboratory, Shanghai Tenth People's Hospital of Tongji University, Shanghai 200072, P.R. China.
authors.forename: Fenyong
authors.initials: F
authors.lastname: Sun
mesh_terms: D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis; D063646:Carcinogenesis / Q000235:genetics; D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000473:pathology; D002453:Cell Cycle / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D049109:Cell Proliferation / Q000235:genetics; D056766:Cyclin G1 / Q000096:biosynthesis; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics* / Q000473:pathology; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000235:genetics*; D012516:Osteosarcoma / Q000235:genetics* / Q000473:pathology
chemical_list: D051017:Apoptosis Regulatory Proteins; C491073:BCL2L2 protein, human; C534702:CCNG1 protein, human; D056766:Cyclin G1; C531907:MIRN122 microRNA, human; D035683:MicroRNAs