Figure 7. Genes encoding CXCR2 ligands are highly expressed by spontaneous intestinal tumors and form part of the secretome of Apc^Min/+ adenomas.

(A and B) Relative mRNA expression of Cxcr2 and its ligands in tumors from Apc^Min/+ (A) and AhCreER;Apc^fl/+;Pten^fl/fl (B) mice. Tumors from AhCreER;Apc^fl/+;Pten^fl/fl mice were harvested approximately 50 days after cre activation (4 i.p. injections of cre inducers) and categorized as invasive (Inv) or noninvasive based on examination of intestinal tissue and confirmed by microscopic examination of H&E-stained sections. Mean expression in adjacent normal tissue (C) is set to 1. (C) CXCL1, CXCL2, and CXCL5 protein in lysates of Apc^Min/+ adenomas and resting normal intestine from C57BL/6 mice, measured by ELISA. (D) Mouse cytokine antibody arrays were exposed to conditioned media from cultures of WT intestinal crypts or Apc^Min/+ adenomas, and fluorescence intensity on anti-CXCL1, -CXCL2, -CXCL5, and -CXCL7 Ab was read on a microarray scanner (n = 5 per group). *P < 0.05, **P < 0.01, ***P < 0.001, Mann-Whitney test (A, C, and D) or 1-way ANOVA with multiple comparison post-test (B). Box and whisker plots show median (lines within boxes), interquartile range (bounds of boxes), and upper and lower range (whiskers).