Although there was no significant difference in the proportion of Ly6G+CD11b+ neutrophils, Ly6G−CD11b+ macrophages and CD4 T cells in the peritoneal fluid between the two groups on day 14 (Figs. 6 and 7A, B and E), the peritoneal fluid of the MUC2 RNAi-1 tumor-bearing mice treated with IL6-neutralizing antibody had a significantly greater proportion of CD8 T cells than MUC2 RNAi-1 tumor-bearing mice treated with the control antibody on day 14 (Fig. 7C, D and F). Here, IL6 is linked to neoplasm.