CXCL12 and hepatocellular carcinoma: A mounting evidence has shown that cytokines (IL-1, IL-6, IL-8, tumor necrosis factor-α), chemokines (CXCL12-CXCR4 axis, CX3CL1-CX3CR1 axis, and CCL20-CCR6 axis), and signaling pathways (NF-κB JAK-STAT3 EGFR signaling) are implicated in HCC [35,44].