The Microenvironmental Effect in the Progression, Metastasis, and Dormancy of Breast Cancer: A Model System within Bone Marrow

Figure 2

Stromal cells in the endosteal region of the bone marrow produce the chemokine, CXCL12, a known regulator in hematopoiesis. Through an interaction between CXCL12 and CXCR4 (a receptor on the BCC), malignant cells are drawn from circulation to the stromal niche. There, BCCs may form gap junctions with osteoblasts, which facilitates the intercellular transfer of small molecules such as miRNAs. Experimental evidence demonstrates that micro-RNAs can traverse gap junctions and induce dormancy of BCCs.