The resulting bone resorption provides new niches for cancer cell colonization and releases cytokines like BMP, transforming growth factor-β (TGF-β), fibroblast growth factor (FGF), and platelet-derived growth factor (PDGF) from the bone matrix, further promoting tumor proliferation and PTHrP production, thus perpetuating bone destruction (109). The gene discussed is TGFB1; the disease is cancer.