Arginine metabolic pathways involved in the modulation of tumor-induced angiogenesis by macrophages.
Neovascularization, an essential step for tumor progression and metastasis development, can be modulated by the presence of macrophages (Mps) in the tumor microenvironment. The ability of Mps to regulate the angiogenicity of the LMM3 tumor cell line was studied. Peritoneal Mps from LMM3 tumor-bearing mice (TMps) potentiate in vivo LMM3 angiogenicity. These results were confirmed by CD31 immunoblotting assays. The activity of TMps depended on nitric oxide synthase (NOS) and arginase (A) activity. By immunoblotting we evidenced that AI and AII isoforms were up-regulated in TMps while the inducible and neuronal NOS isoforms were highly expressed in normal Mps. TMps might positively modulate tumor growth by stimulating angiogenic cascade mainly through polyamine synthesis.
Davel
Lilia Elena
LE
Instituto de Oncología Angel H. Roffo, Av. San Martín 5481, CP 1417, Buenos Aires, Argentina.
Jasnis
María Adela
MA
de la Torre
Eulalia
E
Gotoh
Tomomi
T
Diament
Miriam
M
Magenta
Gabriela
G
Sacerdote de Lustig
E
E
Sales
María Elena
ME
D000818:Animals; D001119:Arginase / Q000502:physiology; D001120:Arginine / Q000378:metabolism*; D005260:Female; D007527:Isoenzymes / Q000378:metabolism; D017737:Macrophages, Peritoneal / Q000201:enzymology / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000098:blood supply* / Q000201:enzymology / Q000378:metabolism*; D009389:Neovascularization, Pathologic; D019001:Nitric Oxide Synthase / Q000502:physiology; D014407:Tumor Cells, Cultured
D007527:Isoenzymes; D001120:Arginine; D019001:Nitric Oxide Synthase; D001119:Arginase