CXCL12 and neoplasm: The results showed that the expression of CXCL1, 2, 3, 12, and 14 in BRCA was lower in tumor tissues, and the expression of CXCL9, 10, 11, and 13 was higher than its expression in normal tissues; in COAD, the expression of CXCL12, 13 and 14 was lower than that in normal tissues, and the expression of CXCL1, 2, 3, 5, 8, 9, 10 and 11 was higher than that in normal tissues; in PDAC, the expression of CXCs was significantly higher than that in normal tissues, except CXCL2, 7, 11 and 12 (Figure 4).