Figure 1. Targeting endotrophin in breast cancer. Researchers from The University of Texas Southwestern Medical Center published in The Journal of Clinical Investigation that blocking the extracellular protein endotrophin reduced breast tumor growth and metastasis.

Adipocytes in the tumor stroma secrete multiple factors that interact with other stromal cell types as well as tumor cells [a].

The JCI paper identified endotrophin, an extracellular cleavage product of collagen VI (COL6), as a factor that influenced both cancer cells and stromal cells [b]. In cancer cells, endotrophin induced the epithelial-mesenchymal transition, which led to increased metastases. In the tumor stroma, endotrophin recruited and activated macrophages and endothelial cells, which in turn promoted tumor growth through increased angiogenesis [c].