These perivascular immunosuppressive macrophages and myeloid-derived suppressor cells could also be recruited by chemokine CXCL12 and granulocyte-macrophage colony-stimulating factor (GM-CSF) induced by pancreatic cancer cells treated with paclitaxel and gemcitabine/5-FU, respectively [39,40]. Here, CXCL12 is linked to pancreatic neoplasm.