CCN2 and osteoarthritis: Furthermore, in certain pathologies such as osteochondral defects [46], osteoarthritis [42, 47–49], and inflammatory joint diseases [50–53], chondrocytes have been demonstrated to express various proangiogenic factors, including VEGF [46, 54–56], connective tissue growth factor (CTGF) [57], FGF-2 [42], tumor necrosis factor-α (TNF-α) [58], and matrix metalloproteinases (MMP) 9 and 13 [59, 60].