Objective: To elucidate the role of microRNA-31 (miR-31) in osteosarcoma and the molecular mechanism of miR-31 in the proliferation, migration, and invasion of osteosarcoma.
Patients and methods: Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was used to examine the expression of microRNA-31 in human osteosarcoma tissues. Pearson's chi-squared test was used to analyze the correlation between microRNA-31 and clinicopathological features. Proliferation, migration, invasion, and PI3K3C2A protein in treated osteosarcoma cells were detected by Cell Counting Kit-8 (CCK-8) assay, transwell assay without Matrigel, transwell assay with Matrigel, and Western blot analysis, respectively.
Results: qRT-PCR showed that miR-31 was down-regulated in osteosarcoma tissues compared with paired para-tumor bone tissues. The lower level of miR-31 was closely associated with high-grade osteosarcoma, metastasis, and poor overall survival. CCK-8 and transwell assay showed that miR-31 inhibited osteosarcoma cells proliferation, migration, and invasion. According to luciferase assay, miR-31 inhibits osteosarcoma cell proliferation, migration, and invasion through inhibiting PIK3C2A. Reversely, overexpression of PIK3C2A inhibited partial effect of miR-31 on proliferation, migration, and invasion in vitro.
Conclusions: MiR-31 inhibits osteosarcoma cell proliferation, migration, and invasion by targeting PICK3C2A. MiR-31 can thus be used as a therapeutic target in osteosarcoma treatment.