| Project/Area Number |
18590259
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
General medical chemistry
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| Research Institution | Kanazawa University |
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Principal Investigator |
TAKUWA Noriko Kanazawa University, Graduate School of Medicine, Research Associate (70150290)
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| Project Period (FY) |
2006 – 2007
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| Project Status |
Completed (Fiscal Year 2007)
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| Budget Amount *help |
¥3,980,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥480,000)
Fiscal Year 2007: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
Fiscal Year 2006: ¥1,900,000 (Direct Cost: ¥1,900,000)
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| Keywords | Cancer / Signal transduction / Lipids / Bioactive molecules / G protein-coupled receptor / がん血管新生 / スフィンゴシン-1-リン酸 / ノックアウトマウス / 細胞遊走 / スフィンゴシン / がん / 血管新生 / 細胞内情報伝達 / 血管内皮細胞 |
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| Research Abstract |
Plasma-derived lipid mediator sphingosine- 1-phosphate (S1P) acts via the G protein-coupled SIP receptor family to regulate a variety of physiological and pathological responses. S1P_1 receptor mediates endothelial cell migration and vascular maturation, promoting vascular integrity. We have previously shown that S1P_2R is distinct from SlP_1R in that it negatively regulates cell migration and endothelial capillary tube formation hi vitro. In the present study we investigated the role of host cell S1P_2R in tumor growth and angiogenesis by comparing S1P_2 knock out (KO) and their wild type (WT) littermate mice. Lewis lung carcinoma cells and B16BL6 melanoma cells were subcutaneously injected to S1P_2KO and WT mice and allowed to grow for 3 weeks. Tumors of either cell type grew substantially more rapidly in S1P_2KO as compared with WT mice. Tumors in S1P_2KO mice displayed significant increases in the number of blood vessels, blood vessel cross sectional area and association of desmin-positive mural cells around the tumor vessels. Leakage of intravenously injected FITC-dextran per a unit area of tumor was increased in S1P_2KO compared with WT mice, in part because of increased numbers of vessels. Tumors in S1P_2KO mice also showed upregulation of angiogenic factors including VEGF-A, Notch ligand Delta-like ligand 4 and TGFβ1. The results indicate that host cell S1P_2R negatively regulates tumor growth and angiogenesis in vivo, with inhibition of angiogenic gene expression and mural cell recruitment. Selective activation of S1P_2R would be a promising novel anti-tumor therapeutic strategy.
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