CXCR4 and familial pancreatic carcinoma: In pancreatic cancer, gemcitabine treatment activated NF-κB and HIF-1α via ROS-mediated activation of ERK1/2 and Akt, upregulating chemokine receptor 4 (CXCR4) expression and contributing to gemcitabine resistance by CXCR4/chemokine 12 (CXCL12) signaling [65, 66].