EFEMP2 and osteoarthritis: Lei et al. investigated the function of Fibulin-4 in cartilage development and found that Fibulin-4 regulates Wnt/β-catenin signaling by promoting the expression of Wnt-3a and β-catenin and reducing the activity of GSK-3β in chondrocytes of human osteoarthritis, thus affecting chondrocyte differentiation, while Fibulin-4 effectively inhibits the Wnt inhibitor DKK 1 and plays an indirect role in regulating the Wnt signaling pathway (Shangguan et al., 2017).