CCL1 and colorectal cancer: The concentrations of CCL1, CCL11, and CCL26 were elevated in the peripheral blood of patients with stage IV colorectal cancer (one-way ANOVA, CCL1 control vs stage IV, p < 0.0001; CCL11 control vs stage IV, p < 0.0001; CCL26 control vs stage IV, p < 0.0001), suggesting that activation of the pro-tumor function of Th2 cells may exist in stage IV patients (Figure 5D).