CCL2 and hepatocellular carcinoma: NK cytotoxicity against HCC cells was significantly improved by the blockade of IL-6 or MCP1 in the conditioned media of their co-culture (Figure 6F; untreated 8.00%, anti-IL-6 14.20%, anti-MCP1 18.24%, Comb 17.41%; * p < 0.05; ** p < 0.001).