In vivo assessment of tumoral angiogenesis.
Vessel size imaging (VSI) for brain tumor characterization was evaluated and the vessel size index measured by MRI (VSIMRI) was correlated with VSI obtained by histology (VSIhisto). Blood volume (BV) and VSI maps were obtained on 12 rats by simultaneous measurements of R2* and R2, before and after the injection of a macromolecular contrast agent, AMI-227. Immunostaining of collagen IV in vessels was performed. An expression was derived for evaluating VSI from stereologic measurements on histology data (VSIhisto). On BV and VSI images obtained from large-size tumors (n = 9), three regions could be distinguished and correlated well with histological sections: a high BV region surrounding the tumor, a necrotic area where BV is very low, and a viable tumor tissue region showing lower BV but higher VSI than the normal rat cortex, with the presence of larger vessels. The quantitative analysis showed a good correlation (Spearman rank's rho = 0.74) between VSIhisto and VSIMRI with a linear regression coefficient of 1.17. The good correlation coefficient supports VSI imaging as a quantitative method for tumor vasculature characterization.
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Unité mixte INSERM 594/Université Joseph Fourier, Laboratoire de Recherche Conventionné du CEA No. 30V, Hôpital Albert Michallon, and European Synchrotron Radiation Facility, Grenoble, France. Irene.Tropres@ujf-grenoble.fr
Lamalle
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Péoc'h
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Farion
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R
Usson
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Décorps
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Rémy
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C
D000818:Animals; D001810:Blood Volume / Q000502:physiology; D001932:Brain Neoplasms / Q000098:blood supply* / Q000473:pathology; D024141:Collagen Type IV / Q000032:analysis; D003287:Contrast Media; D003911:Dextrans; D004195:Disease Models, Animal; D052203:Ferrosoferric Oxide; D005910:Glioma / Q000098:blood supply* / Q000473:pathology; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D007501:Iron; D016014:Linear Models; D046911:Macromolecular Substances; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles; D008297:Male; D008833:Microcirculation / Q000473:pathology; D009336:Necrosis; D009389:Neovascularization, Pathologic / Q000473:pathology*; D010087:Oxides; D051381:Rats; D017208:Rats, Wistar; D018709:Statistics, Nonparametric
D024141:Collagen Type IV; D003287:Contrast Media; D003911:Dextrans; D046911:Macromolecular Substances; D058185:Magnetite Nanoparticles; D010087:Oxides; C097921:ferumoxtran-10; D007501:Iron; D052203:Ferrosoferric Oxide