title: MiR-223/Ect2/p21 signaling regulates osteosarcoma cell cycle progression and proliferation.
abstract: Osteosarcoma is one of the most common tumors. The mechanisms of formation and development of osteosarcoma have been studied for a long time. Recently, more and more evidence showed that miRNAs play important roles in regulating tumor growth. In this study we found that miRNA-223 was downregulated in both osteosarcoma patients' tumor tissues and osteosarcoma cell lines. Overexpression of miRNA-233 greatly inhibited the proliferation of Saos-2 cells. Cell cycle analysis by flow cytometry showed the arrest of cell cycle progression at the G1 phase. Further mechanistic study indicated that Ect2 was directly targeted by miR-223. Downregulation of Ect2 by miR-223 induces the expression of p21, p27 and the phospharylation of retinoblastoma, which are involved in the G1 block. We concluded that miR-223 functions as a tumor suppresser in osteosarcoma and miR-223/Ect2/p21 signaling is an important pathway that regulates the osteosarcoma cell cycle progression and proliferaion.
authors.affiliation: Department of Orthopaedic Surgery, Beijing Shijitan Hospital Affiliated to Capital Medical University, Beijing, PR China.
authors.forename: Jianli
authors.initials: J
authors.lastname: Xu
authors.forename: Qi
authors.initials: Q
authors.lastname: Yao
authors.forename: Yu
authors.initials: Y
authors.lastname: Hou
authors.forename: Meng
authors.initials: M
authors.lastname: Xu
authors.forename: Sheng
authors.initials: S
authors.lastname: Liu
authors.forename: Longqiu
authors.initials: L
authors.lastname: Yang
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
mesh_terms: D001859:Bone Neoplasms / Q000235:genetics / Q000473:pathology*; D002453:Cell Cycle; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism*; D005434:Flow Cytometry; D059585:G1 Phase Cell Cycle Checkpoints; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D012516:Osteosarcoma / Q000235:genetics / Q000473:pathology*; D010766:Phosphorylation; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D016160:Retinoblastoma Protein / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D050759:Cyclin-Dependent Kinase Inhibitor p21; D035683:MicroRNAs; D011518:Proto-Oncogene Proteins; D016160:Retinoblastoma Protein; C489850:ECT2 protein, human; C525067:MIR223, human