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Angiopoietin-2 is implicated in the regulation of tumor angiogenesis.

ABSTRACT: We addressed the effect of angiopoietin expression on tumor growth and metastasis. Overexpression of angiopoietin-2 (Ang-2) in Lewis lung carcinoma and TA3 mammary carcinoma cells inhibited their ability to form metastatic tumors and prolonged the survival of mice injected with the corresponding transfectants. In contrast, angiopoietin-1 (Ang-1) overexpression had no detectable effect on the ability of either tumor type to disseminate. Tumors derived from Ang-2-overexpressing cells displayed aberrant angiogenic vessels that took the form of vascular cords or aggregated vascular endothelial cells with few associated smooth muscle cells. These vascular cords or aggregates were accompanied by endothelial and tumor cell apoptosis, suggesting that an imbalance in Ang-2 expression with respect to Ang-1 and vascular endothelial growth factor may disrupt angiogenesis and tumor survival in vivo. Our observations suggest that Ang-2 may play an important role in regulating tumor angiogenesis.

SUBMITTER: Yu Q

PROVIDER: S-EPMC1850318 | biostudies-literature | 2001 Feb

REPOSITORIES: biostudies-literature

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Angiopoietin-2 is implicated in the regulation of tumor angiogenesis.

Yu Q Q Stamenkovic I I

The American journal of pathology 20010201 2

We addressed the effect of angiopoietin expression on tumor growth and metastasis. Overexpression of angiopoietin-2 (Ang-2) in Lewis lung carcinoma and TA3 mammary carcinoma cells inhibited their ability to form metastatic tumors and prolonged the survival of mice injected with the corresponding transfectants. In contrast, angiopoietin-1 (Ang-1) overexpression had no detectable effect on the ability of either tumor type to disseminate. Tumors derived from Ang-2-overexpressing cells displayed abe ...[more]

PMID: 11159193

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| S-EPMC4363832 | biostudies-literature

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Project description:Angiogenesis, the expansion of preexisting blood vessels, is a complex process required for tumor growth and metastasis. Although current antiangiogenic strategies have shown promising results in several cancer types, identification of additional antiangiogenic targets is required to improve the therapeutic response. Herein, we show that the microtubule-binding protein CLIP-170 (cytoplasmic linker protein of 170 kDa) is highly expressed in breast tumor samples and correlates positively with blood vessel density. Depletion of CLIP-170 significantly impaired vascular endothelial tube formation and sprouting in vitro and inhibited breast tumor growth in mice by decreasing tumor vascularization. Our data further show that CLIP-170 is important for the migration but not the proliferation of vascular endothelial cells. In addition, CLIP-170 promotes the polarization of endothelial cells in response to the angiogenic stimulus. These findings thus demonstrate a critical role for CLIP-170 in tumor angiogenesis and suggest its potential as a novel antiangiogenic target.

| S-EPMC4875523 | biostudies-literature

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