| First Author | Kerber M | Year | 2008 |
| Journal | Cancer Res | Volume | 68 |
| Issue | 18 | Pages | 7342-51 |
| PubMed ID | 18794121 | Mgi Jnum | J:141218 |
| Mgi Id | MGI:3817783 | Doi | 10.1158/0008-5472.CAN-07-6241 |
| Citation | Kerber M, et al. (2008) Flt-1 signaling in macrophages promotes glioma growth in vivo. Cancer Res 68(18):7342-51 |
| abstractText | Several lines of evidence indicate that Flt-1, a fms-like tyrosine kinase receptor, which binds to vascular endothelial growth factor (VEGF)-A, VEGF-B, and PlGF, is a positive regulator of angiogenesis in the context of tumor growth and metastasis. However, the molecular basis of its action is still not clear. Besides endothelial cells, Flt-1 is also expressed by other different cell types, including myeloid hematopoeitic cells (monocytes and macrophages). To examine the functions of Flt-1 expressed by bone marrow-derived myeloid cells in supporting tumor growth and angiogenesis, Flt-1 tyrosine kinase-deficient (Flt-1 TK-/-) bone marrow cells were transplanted into lethally irradiated syngeneic recipients. After hematopoietic reconstitution, we orthotopically implanted syngeneic wild-type glioma cells or glioma cells overexpressing either VEGF(164) or PlGF-2. Loss of Flt-1 signaling in bone marrow-derived myeloid cells led to a significant decrease in tumor volume and vascularization in gliomas. VEGF but not PlGF overexpressed by glioma cells restored the tumor growth rate in Flt-1 TK-/- bone marrow chimera. VEGF and PlGF overexpression by tumor cells induced an accumulation of bone marrow-derived myeloid cells into tumor tissue. This infiltration was decreased in tumors grown in Flt-1 TK-/- bone marrow chimeras. When investigating chemokines and growth factors involved in myeloid cell recruitment, we determined elevated SDF-1/CXCL12 levels in VEGF- and PlGF-overexpressing tumors. Collectively, these results suggest that Flt-1 signaling in myeloid cells is essential to amplify the angiogenic response and to promote glioma growth. |
