Figure 5

CXCL1 contributed to in vivo human CRC tumor growth. a SW620 cells stably expressing two distinct CXCL1 specific shRNAs had suppressed xenograft tumor growth in immunocompromised mice (n = 4 per group) with tumor images at right. b Immunofluorescence of human CRC detected CXCL1 protein expression (red) in CRC epithelia (asterisks) and co-localization with tumor myofibroblasts (arrowheads), which expressed α-smooth muscle actin (green). c, d In primary stage I–IV human CRC, mRNA levels of CXCL1 show a moderate correlation with CXCR2 (Spearman r = 0.34; CI 0.20–0.48) but not CXCR1 (Spearman r = −0.04; 95% CI −0.20 to 0.11).