title: Tumor angiogenesis--characteristics of tumor endothelial cells.
abstract: Tumor blood vessels provide nutrition and oxygen to the tumor, resulting in tumor progression. They also act as gatekeepers, inducing tumor metastasis. Thus, targeting tumor blood vessels is an important strategy in cancer therapy. Tumor endothelial cells (TECs), which line the inner layer of blood vessels of the tumor stromal tissue, are the main targets of anti-angiogenic therapy. Because new tumor blood vessels generally sprout from pre-existing vasculature, they have been considered to be the same as normal blood vessels. However, tumor blood vessels demonstrate a markedly abnormal phenotype that includes several important morphological changes. The degree of angiogenesis is determined by the balance between the angiogenic stimulators and inhibitors released by the tumor and host cells. Recent studies have revealed that TECs also exhibit altered characteristics which depend on the tumor microenvironment. Here, we review recent studies on TEC abnormalities and heterogeneity with respect to tumor progression and consider their therapeutic implications.
authors.affiliation: Vascular Biology, Frontier Research Unit, Institute for Genetic Medicine, Hokkaido University, N15 W7, Kita-ku, Sapporo, 060-0815, Japan. khida@igm.hokudai.ac.jp.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Hida
authors.affiliation: Vascular Biology, Frontier Research Unit, Institute for Genetic Medicine, Hokkaido University, N15 W7, Kita-ku, Sapporo, 060-0815, Japan.
authors.forename: Nako
authors.initials: N
authors.lastname: Maishi
authors.affiliation: Vascular Biology, Frontier Research Unit, Institute for Genetic Medicine, Hokkaido University, N15 W7, Kita-ku, Sapporo, 060-0815, Japan.|Department of Oral and Maxillofacial Surgery, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan.
authors.forename: Chisaho
authors.initials: C
authors.lastname: Torii
authors.affiliation: Department of Cardiovascular and Thoracic Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Hida
mesh_terms: D000818:Animals; D004730:Endothelium, Vascular / Q000473:pathology*; D006801:Humans; D009369:Neoplasms / Q000098:blood supply* / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000473:pathology*; D059016:Tumor Microenvironment
keywords: Anti-angiogenic therapy; Blood vessel; Metastasis; Tumor angiogenesis; Tumor endothelial cell