Magnetic resonance imaging for monitoring the effects of thalidomide on experimental human breast cancers.
Thalidomide, which inhibits angiogenesis in certain tumor types, reduced extravasation of a macromolecular contrast medium (MMCM) in a human breast cancer model as assayed by MMCM-enhanced dynamic magnetic resonance imaging (MRI) and fluorescence microscopy in the same tumors. After a 1-week, three-dose course of thalidomide, the mean MRI-assayed endothelial transfer coefficient, K(PS), decreased significantly (p < 0.05) from 19.4 +/- 9.1 to 6.3 +/- 9.1 microl/min.100 cm(3). Correspondingly, microscopic measurements of extravasated MMCM, expressed as fractional area of streptavidin staining, were significantly (p < 0.05) lower in thalidomide-treated tumors (18.6 +/- 11.9%) than in control saline-treated tumors (50.2 +/- 2.3%). On a tumor-by-tumor basis, post-treatment K(PS) values correlated significantly (r(2) = 0.55, p < 0.05) with microscopic measures of MMCM extravasation. However, no significant differences were observed between saline- and thalidomide-treated tumors with respect to rate of growth, vascular richness, or amount of VEGF-containing cells. Because of its sensitivity to the detection of changes in vascular leakage in tumors, this MMCM-enhanced MRI assay could prove useful for monitoring the effects of thalidomide on an individual patient basis. The significant correlation between MRI and fluorescence microscopic measures of MMCM extravasation supports the utility of the non-invasive MRI approach for assessing the action of thalidomide on tumor blood vessels.
Cyran
Clemens C
CC
Center for Pharmaceutical and Molecular Imaging, Department of Radiology, University of California San Francisco, San Francisco, CA 94143-0628, USA.
Sennino
Barbara
B
Chaopathomkul
Bundit
B
Fu
Yanjun
Y
Rogut
Victor S
VS
Shames
David M
DM
Wendland
Michael F
MF
McDonald
Donald M
DM
Brasch
Robert C
RC
D020533:Angiogenesis Inhibitors / Q000008:administration & dosage; D000818:Animals; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000188:drug therapy*; D004195:Disease Models, Animal; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011379:Prognosis; D051381:Rats; D011923:Rats, Nude; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013792:Thalidomide / Q000008:administration & dosage*; D016896:Treatment Outcome
D020533:Angiogenesis Inhibitors; D013792:Thalidomide