CXCL2 and pancreatic adenocarcinoma: Thirdly, the co-expression of CXC chemokines was explored by the Pearson’s correlation coefficient for PAAD samples (TCGA, PanCancer Atlas), and the results showed a significantly positive correlation among the expression of CXCL1, CXCL2, CXCL3, CXCL9, CXCL10, and CXCL11 (Figures 5A and S2).