FIGURE 5.

TGF‐β signaling influences angiogenic processes. Transforming growth factor (TGF)‐β signaling can elicit the secretion of angiogenic proteins, such as vascular endothelial growth factor (VEGF) and Jagged, by different cell types of the liver metastasis. This promotes (CD31⁺) vessel formation. TGF‐β and stromal derived factor (SDF)‐1 secreted by activated hepatic stellate cells (aHSCs) could promote vascular mimicry in tumor cells. Mesenchymal stem cells (MSCs) could promote angiogenesis through shifting TGF‐β responses towards c‐Jun N‐terminal kinases (JNK) signaling. This results in differentiation of MSCs into endothelial cells, and additional secretion of angiogenic factors. Abbreviation: LSEC, liver sinusoid endothelial cell