Fig. 3

Tumor Cells Are An Source of IL-6. A Cytokine array was used to detect untreated medium and MC-38 cells medium after 72 h; arrows indicate the significantly increased cytokines. B The relative quantification of the significantly up-regulated cytokine to positive quality control density ratio by ImageJ software. The positive quality control density was determined for normalization (**P < 0.01, *P < 0.05; data are shown as means ± SD). C Serum interleukin 6 (IL-6) levels in normal individuals and patients with colorectal cancer aged 30-50 years detected by ELISA (***P < 0.001; data are shown as means ± SD; Health group: n = 26; Patients group: n = 18). D The IL-6 levels in serum in WT mice and Apc^Min/+mice were detected at 9, 15, and 24 weeks old by ELISA (*P < 0.05; data are shown as means ± SD; n = 5 per group). E IL-6 mRNA expression was validated in normal intestinal epithelium isolated from Apc^Min/+ mice versus that in intestinal tumors of WT mice by qPCR (*P < 0.05; data are shown as means ± SD; n = 4 per group)