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Small GTPase R-Ras regulates integrity and functionality of tumor blood vessels.

ABSTRACT: We show that R-Ras, a small GTPase of the Ras family, is essential for the establishment of mature, functional blood vessels in tumors. The genetic disruption of R-Ras severely impaired the maturation processes of tumor vessels in mice. Conversely, the gain of function of R-Ras improved vessel structure and blood perfusion and blocked plasma leakage by enhanced endothelial barrier function and pericyte association with nascent blood vessels. Thus, R-Ras promotes normalization of the tumor vasculature. These findings identify R-Ras as a critical regulator of vessel integrity and function during tumor vascularization.

SUBMITTER: Sawada J

PROVIDER: S-EPMC3422514 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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Small GTPase R-Ras regulates integrity and functionality of tumor blood vessels.

Sawada Junko J Urakami Takeo T Li Fangfei F Urakami Akane A Zhu Weiquan W Fukuda Minoru M Li Dean Y DY Ruoslahti Erkki E Komatsu Masanobu M

Cancer cell 20120801 2

We show that R-Ras, a small GTPase of the Ras family, is essential for the establishment of mature, functional blood vessels in tumors. The genetic disruption of R-Ras severely impaired the maturation processes of tumor vessels in mice. Conversely, the gain of function of R-Ras improved vessel structure and blood perfusion and blocked plasma leakage by enhanced endothelial barrier function and pericyte association with nascent blood vessels. Thus, R-Ras promotes normalization of the tumor vascul ...[more]

PMID: 22897853

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