Skip to main content
. Author manuscript; available in PMC: 2019 Apr 1.
Published in final edited form as: Cell Metab. 2019 Jan 8;29(1):6–8. doi: 10.1016/j.cmet.2018.12.014

Figure 1. Bone Metastasis and the Metastatic Niche.

Figure 1.

Circulating tumor cells extravasate and seed into the bone (1). These cells interact with the osteogenic niche in the early stages of metastasis, through connexin 43 and E/N-cadherin, activating calcium and mTOR signaling to promote tumor growth (2). Later, during disease progression, tumor cells interact with the bone-resorbing osteoclasts through various mechanisms, thereby stimulating bone destruction (3). TGFβ and calcium are released as a consequence of osteoclastic bone destruction (4). This can enhance connexin 43 expression and provide more calcium to perpetuate the cycle of growth.