Down-regulation of MIAT suppresses osteosarcoma progression by acting as a ceRNA for miR-141-3p to regulate SIX1-mediated PI3K/AKT pathway

OBJECTIVE: Osteosarcoma (OS) is a frequent bone malignancy. Long non-coding RNA myocardial infarction associated transcript (MIAT) has been reported to be involved in the development of human cancers. including OS. However. the mechanism underlying MIAT in OS progression remains largely unclear. PATIENTS AND METHODS: The expression levels of MIAT and sineoculis homeobox homolog 1 (SIX1) in OS tissues and cells were detected by quantitative real-time polymerase chain reaction and Western blot. Cell viability, apoptosis. migration and invasion of OS cells were determined by MTT, flow cytometry and transwell assays, respectively. The target interaction among MIAT, miR-141-3p and SIX1 was analyzed by bioinformatics analysis and luciferase reporter assay. Phosphatidylinositide 3-kinases (PI3K)/protein kinase B (AKT) pathway was evaluated by Western blot. RESULTS: MIAT and SIX1 expression levels were enhanced in OS tissues and cells. Knockdown of MIAT or SIX1 repressed cell viability. migration and invasion but promoted apoptosis in OS cells. Moreover. overexpression of SIX1 reversed the inhibitive role of MIAT silence in OS progression. Furthermore, MIAT could increase SIX1 expression by competitively sponging miR-141-3p. Besides, inhibition of MIAT blocked PI3K/AKT pathway by decreasing SIX1 in OS cells. CONCLUSIONS: MIAT silence suppresses OS progression through inactivating PI3K/AKT signaling by sponging miR-141-3p to regulate SIX1, indicating a novel target for the treatment of OS.