Figure 3.

Tumor microenvironment in pancreatic cancer. Pancreatic cancer cells secrete multiple cytokines (such as IL-10, TGF-β, and IL-23) and chemokines (such as CXCL1-3, CXCL5, CXCL12, CCL2, and VEGFα) to activate surrounding stromal cells and attract immunosuppressive cells such as Treg, MDSCs, and TAMs to cluster at tumor sites. High expression of glycolytic enzymes (such as HK2) in TAMs enhances its glycolysis, but also promotes the glycolytic levels of pancreatic cancer cells, which impacts on the growth of pancreatic cancer cells. MDSCs, myeloid-derived suppressor cells; TAMs, tumor-associated macrophages; PSCs, pancreatic stellate cells; HK2, hexokinase 2.