Fig. 3

TheArnt^−/−tumor microenvironment enhances neutrophil recruitment and functions in promoting colorectal cancer growth. Colorectal cancer induction for 80 days after the injection of azoxymethane (AOM) and the addition of dextran sulfate sodium salt (DSS) to the drinking water. A A typical photo of colorectal cancer. Representative of three independent experiments. B Summary of the number (No.) of colonic tumors. The graph summarizes data from three independent experiments with thirteen mice per group. C Summary of tumor diameter. The graph summarizes data from three independent experiments with thirteen mice per group. D Immunohistochemistry analysis of colorectal cancer after staining with anti-Gr1 antibody. Scales bars, 50 μm. Original magnification, 400X. Representative of three independent experiments. E Percentages of neutrophils in the colon and MLN. Dot-plots present the representative data from flow cytometry analysis is shown on the left, and the data are summarized on the right. The graph summarizes data from three independent experiments with six mice per group. F Tumor-infiltrating neutrophils were isolated and stimulated with LPS in vitro as indicated to detect NETs. Typical NET images are displayed (left), and the percentage of NETs-forming cells is quantified (right). Scales bars, 20 μm. Original magnification, 200X. The graph summarizes data from three independent experiments with six mice per group. G Suppressive assay of tumor-infiltrating neutrophils from tumor-bearing WT and Arnt^−/− mice. Data from coculture with allogeneic CD4⁺ T cells with different ratio between neutrophils and T cells are shown. Representative of three independent experiments. H Indicated chemokine production in serum from tumor-bearing WT and Arnt^−/− mice. Representative of three independent experiments. I-J Effects of neutrophils injected with anti-Gr1 mAb on colorectal cancer incidence (I) and diameter (J). The graph summarizes data from three independent experiments with twelve mice per group. ***P < 0.001, compared with the indicated groups