Fig. 2: MMP-2 is highly expressed in osteosarcoma tissues, and NGF promotes MMP-2-dependent cell migration in human osteosarcoma.

A–E MMPs mRNA expression in normal and osteosarcoma tissue was analyzed in samples from the GEO GSE16088 dataset. F Osteosarcoma cells were incubated with NGF for 24 h, before determining 4 potential MMPs candidates by qPCR. G–I Osteosarcoma cells were incubated with varying concentrations of NGF (30, 50, or 100 ng/mL) for 24 h, and the levels of MMP-2 expression were examined by qPCR and Western blot assays. J–Q Osteosarcoma cells were transfected with MMP-2 siRNAs for 24 h, then stimulated with NGF, and cell migration, invasion, as well as levels of MMP-2 expression, were examined by the wound healing, Transwell, and Western blot assays (scale bar 500 μm). R, S Normal bone and osteosarcoma specimens were subjected to IHC staining with MMP-2 antibody (scale bar 100 μm), then quantified. T A positive correlation between NGF and MMP-2 protein expression in human osteosarcoma tissue. All experiments were repeated 3 to 5 times. *p < 0.05 compared with the control group; ^#p < 0.05 compared with the NGF-treated group.