Open AccessInhibition of miRNA‑21 attenuates the proliferation and metastasis of human osteosarcoma by upregulating PTEN
Author(s) -
Chen Li,
Beilei Xu,
Xinxin Miu,
Zhongbo Deng,
Hang Liao,
Hao Lu
Publication year - 2017
Publication title -
experimental and therapeutic medicine
Language(s) - English
Resource type - Journals
eISSN - 1792-1015
pISSN - 1792-0981
DOI - 10.3892/etm.2017.5477
Subject(s) - tensin , pten , protein kinase b , pi3k/akt/mtor pathway , downregulation and upregulation , cancer research , cell growth , transfection , microrna , microbiology and biotechnology , biology , western blot , chemistry , signal transduction , cell culture , biochemistry , genetics , gene
The present study aimed to investigate the expression of micro (mi)RNA-21 in osteosarcoma cells, and its role in inhibiting the invasion and metastasis of osteosarcoma. Human osteosarcoma MG-63 cells and osteoblast hFOB1.19 cells were used to compare the expression of miRNA-21 using reverse transcription-quantitative polymerase chain reaction analysis. A miRNA-21 mimic or inhibitor were transfected into the MG-63 cells to upregulate and downregulate the expression of miRNA-21, respectively. The present study investigated the proliferation and invasion of transfected MG-63 cells using MTT and Transwell assays. Western blot analyses were used to investigate the regulation of important proteins in the phosphatase and tensin homolog/phosphoinositide 3-kinase/RAC-α serine/threonine-protein kinase (PTEN/PI3K/AKT) signaling pathway. Compared with hFOB1.19 cells, miRNA-21 expression was significantly upregulated in the MG-63 cells (P<0.01), which lead to increased proliferation. Downregulating miRNA-21 expression reduced the proliferation of MG-63 cells compared with hFOB1.19 cells. Invasion assays and western blot analyses revealed that the overexpression of miRNA-21 significantly enhanced the invasion ability of MG-63 cells and the expression of phosphorylated (p-)AKT, while downregulation of miRNA-21 expression reduced the protein level of AKT and p-AKT. In the MG-63 cells, miRNA-21 upregulation significantly inhibited the protein level of PTEN, resulting in significantly increased AKT and PI3K protein levels (P<0.01). In conclusion, the results of the present study indicate that the expression of miRNA-21, PI3K and AKT is increased in the osteosarcoma cell line MG-63, which results in reduced expression of PTEN and increased expression of proteins in the PI3K/AKT signaling pathway, and thus increases the aggressiveness of osteosarcoma cells.