Figure 6: Fibroblast-derived VEGF enriches VEGFR1+ cells bone marrow and pre-metastatic sites.

(a) Immunohistochemical expression of mouse VEGF in the tumour xenografts established with KYSE150-Id1, KYSE150-Id1-shIGF2 or vector control cells (scale bar, 20 μm). (b) Flow cytometry data showing the expression of VEGFR1+ cells in bone marrow (upper panel) and lungs (lower panel) of mice with subcutaneous implantation of indicated fibroblasts and treatment (female 6–8-week-old nude mice, n=3 per group). (c,d) Flow cytometry analysis of VEGFR1+ cells (c) and comparison of tumour volume (d) of subcutaneous tumour xenografts established from co-implantation of KYSE150 cells and indicated NEFs in the presence or absence of Avastin treatment. Photographs show representative tumours of the three groups (female 6–8-week-old nude mice, n=6 per group; scale bar, 1 cm). Bars, s.d.; *P<0.05; **P<0.01; ***P<0.001 by Student’s t-test.