Downregulation of long non-coding RNA PVT1 enhances fracture healing via regulating microRNA-497-5p/HMGA2 axis

Fragility fracture is a common and serious complication of osteoporosis. Abnormal expression of long non-coding RNAs is closely related to orthopedic diseases and bone metabolism. In the study, the role of lncRNA PVT1 during fracture healing, and the potential mechanism were explained. In the present study, 80 cases with fragility fracture were collected, serum samples were also collected at 7, 14, 21 days after standardized fixation therapy. qRT-PCR was applied for the measurement of mRNA levels. hFOB1.19 cells were recruited for the cell experiments, and the cell viability and apoptosis were detected. Luciferase reporter gene assay was performed for target gene confirmation. It was found that the level of PVT1 increased gradually, while miR-497-5p showed a downward trend over time in both intra-articular and hand fracture patients, and the changes reached a significant level at 21 day after treatment. In vitro experiments demonstrated that PVT1 knockdown promoted cell proliferation and inhibited cell apoptosis in HFOB1.19 cells. LncRNA PVT1 acts as a competing endogenous RNA (ceRNA) of miR-497-5p, and the influence of PVT1 knockdown on HFOB1.19 cell proliferation and apoptosis was reversed by miR-497-5p inhibition. HMGA2 is the target gene of miR-497-5p. It was concluded that LncRNA PVT1 silencing may enhance fracture healing via mediating miR-497-5p/HMGA2 axis.