Figure 8
From: Macrophages may promote cancer growth via a GM-CSF/HB-EGF paracrine loop that is enhanced by CXCL12
GM-CSF and HB-EGF release from cancer cells and mononuclear phagocytes. ELISA analysis (see Methods section) revealed that GM-CSF and HB-EGF were barely detectable under basal conditions in supernatants from HeLa/DLD-1 cells or mononuclear phagocytes, respectively, but accumulated 24 hours after stimulation. (A) Stimulation of HeLa/DLD-1 with 25 ng/mL HB-EGF or supernatant from mononuclear phagocytes (SN2) induced GM-CSF release into supernatants. 100 μg/mL anti-HB-EGF blocking Abs reduced the supernatant-dependent release (p < 0.05). (B) Stimulation of mononuclear phagocytes with 25 ng/mL GM-CSF or supernatant from GM-CSF-positive cancer cells (SN) led to the accumulation of HB-EGF in supernatants. 100 μg/mL anti-GM-CSF neutralising Abs suppressed the supernatant-dependent release (p < 0.05). The means ± SD out of 10 experiments are depicted.