title: MicroRNA-133a Inhibits Osteosarcoma Cells Proliferation and Invasion via Targeting IGF-1R.
abstract: OBJECTIVE
  MicroRNAs (miRNAs) are a class of small noncoding RNAs that regulate gene expression by repressing translation or cleaving RNA transcripts in a sequence-specific manner. Downregulated microRNAs and their roles in cancer development have attracted much attention. A growing body of evidence showed that microRNA-133a (miR-133a) has inhibitory effects on cell proliferation, migration, invasion, and metastasis of osteosarcoma.
  
  
  METHODS
  MiR-133a expression in human osteosarcoma cell lines and human normal osteoblastic cell line hFOB was investigated by real-time PCR (RT-PCR). The role of miR-133a in human osteosarcoma growth and invasion was assessed in cell lines in vitro and in vivo. Then, luciferase reporter assay validated IGF-1R as a downstream and functional target of miR-133a, and functional studies revealed that the anti-tumor effect of miR-133a was probably due to targeting and repressing of IGF-1R expression.
  
  
  RESULTS
  MiR-133a was lower expressed in human osteosarcoma cell lines than human normal osteoblastic cell line hFOB and its effect on inhibiting proliferation, invasion and metastasis is mediated by its direct interaction with the IGF-1R. Furthermore, the tumour-suppressive function of miR-133a probably contributed to inhibiting the activation AKT and ERK signaling pathway.
  
  
  CONCLUSIONS
  MiR-133a suppresses osteosarcoma progression and metastasis by targeting IGF-1R in human osteosarcoma cells, providing a novel candidate prognostic factor and a potential anti-metastasis therapeutic target in osteosarcoma.
authors: Department of Orthopedic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, P.R. China.
authors: Guangnan
authors: G
authors: Chen
authors: Tingting
authors: T
authors: Fang
authors: Zhongming
authors: Z
authors: Huang
authors: Yiying
authors: Y
authors: Qi
authors: Shaohua
authors: S
authors: Du
authors: Tuoyu
authors: T
authors: Di
authors: Zhong
authors: Z
authors: Lei
authors: Xiangyu
authors: X
authors: Zhang
authors: Weiqi
authors: W
authors: Yan
mesh_terms: D001859:Bone Neoplasms / Q000235:genetics* / Q000473:pathology; D001842:Bone and Bones / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D009361:Neoplasm Invasiveness / Q000235:genetics* / Q000473:pathology; D009362:Neoplasm Metastasis / Q000235:genetics / Q000473:pathology; D012516:Osteosarcoma / Q000235:genetics* / Q000473:pathology; D017526:Receptor, IGF Type 1; D017451:Receptors, Somatomedin / Q000235:genetics*
chemical_list: C000597236:IGF1R protein, human; C548234:MIRN133 microRNA, human; D035683:MicroRNAs; D017451:Receptors, Somatomedin; D017526:Receptor, IGF Type 1