Besides the finding of TGF-β1/POSTN/integrin αvβ3 axis in PCa bone metastases, we also found that, in the downstream of integrin αvβ3, there were two key proteins including c-Src (44) and MMP-2 (45), and meanwhile, the function of integrin αvβ3 was regulated by Tenascin-C (46), which are extremely involved in metastasis. This evidence concerns the gene MMP2 and posterior cortical atrophy.