Interestingly, while bone marrow-derived stem cells have been shown to transition into CAFs in mouse models of inflammation-induced gastric cancer to promote tumor growth via expression of IL-6, Wnt5a and BMP4 [83], prostate cancer cell secretion of BMP4 has recently been shown to instruct endothelial cells within the TME to undergo transition into osteoblasts in osteogenic prostate cancer xenograft models, encouraging bone matrix mineralization through BMP4-driven p-SMAD1/Notch and GSK3β/β-catenin/OSX signaling [236]. The gene discussed is SMAD1; the disease is prostate cancer.