Fig. 3

Intratumoral LPS activated NF-κB-IL6-STAT3 axis. A LPS levels in mouse feces and serum by ELISA; HE staining (scale bar, 50 μm) and histology score for colon tissue in the Abx and NC group. B Immunohistochemistry (scale bar, 50 μm) for LPS in subcutaneous and orthotopic tumor tissues and western blot of intratumoral LPS levels from three biological duplications for the Abx and NC group. C Transcription levels of cytokines by RT-qPCR and protein levels of IL6 in cell supernatant by ELISA in RM-1 cultured with LPS (100 μg/ml) for 24 h. D, E Immunofluorescence (scale bar, 100 μm) for p-p65 and p-STAT3 in RM-1 cultured with or without LPS for 24 h; western blot of relative proteins for RM-1 cultured with LPS at different concentrations for 24 h; transcription levels of IL6 by RT-qPCR and western blot of relative proteins in RM-1 cultured with LPS or LPS with BAY-11-7082 for 24 h; protein levels of p-STAT3 and STAT3 in RM-1 cultured with CM or CM with antibody-IL6 for 24 h. F, G IL6 levels in tumor tissue lysate and serum by ELISA. Western blot of relative proteins in tumor from three biological duplications. Immunohistochemistry of tumor tissues for p-p65- and p-STAT3-positive cell (scale bar, 50 μm). Statistical significance was assessed by unpaired Student’s T-test or LSD in one-way ANOVA. *p < 0.05, **p < 0.01, and ***p < 0.001: compared to the NC group; #p < 0.05, ##p < 0.01, and ###p < 0.001: compared to the LPS or CM group