Tomographic Fluorescence Imaging of Tumor Vascular Volume in Mice

Purpose: To prospectively determine the feasibility of imaging vascular volume fraction (VVF) and its therapeutic inhibition in mouse models of cancer with three-dimensional fluorescence molecular tomography (FMT).

Materials and Methods: All studies were approved by the institutional animal review committee and were in accordance with National Institutes of Health guidelines. CT26 colon tumor–bearing mice were imaged with FMT after intravenous administration of long-circulating near-infrared fluorescent blood-pool agents optimized for two nonoverlapping excitation wavelengths (680 and 750 nm). A total of 58 mice were used for imaging VVF to evaluate the following: (a) differences in ectopically and orthotopically implanted tumors (n = 10), (b) cohorts of mice (n = 24) treated with anti–vascular endothelial growth factor (VEGF) antibody, (c) serial imaging in same animal to determine natural course of angiogenesis (n = 4), and (d) dose response to anti-VEGF therapy (n = 20). To compare groups receiving antiangiogenic chemotherapy, analysis of variance was used.

Results: Fluorochrome concentrations derived from FMT measurements were reconstructed with an accuracy of ±10% at 680 nm and ±7% at 750 nm and in a depth-independent manner, unlike at reflectance imaging. FMT measurements of vascular fluorescent probes were linear, with concentration over several orders of magnitude (r > 0.98). VVFs of colonic tumors, which varied considerably among animals (3.5% ± 1.5 [standard deviation]), could be depicted with in vivo imaging in three dimensions with less than 5 minutes of imaging and less than 3 minutes of analysis. The natural course of angiogenesis and its inhibition could be reliably imaged and depicted serially in different experimental setups.

Conclusion: FMT is a tomographic optical imaging technique that, in conjunction with appropriate fluorescent probes, allows quantitative visualization of biologic processes.

© RSNA, 2007

References

  • 1 Hanahan D, Weinberg R. The hallmarks of cancer. Cell 2000; 100: 57–70. Crossref, MedlineGoogle Scholar
  • 2 Carmeliet P, Jain R. Angiogenesis in cancer and other diseases. Nature 2000;407:249–257. Crossref, MedlineGoogle Scholar
  • 3 Libby P, Schonbeck U. Drilling for oxygen: angiogenesis involves proteolysis of the extracellular matrix. Circ Res 2001;89:195–197. Crossref, MedlineGoogle Scholar
  • 4 Libby P, Zhao D. Allograft arteriosclerosis and immune-driven angiogenesis. Circulation 2003;107:1237–1239. Crossref, MedlineGoogle Scholar
  • 5 Sivakumar B, Harry L, Paleolog E. Modulating angiogenesis: more vs less. JAMA 2004;292:972–977. Crossref, MedlineGoogle Scholar
  • 6 McDonald DM, Choyke PL. Imaging of angiogenesis: from microscope to clinic. Nat Med 2003;9:713–725. Crossref, MedlineGoogle Scholar
  • 7 Miller JC, Pien HH, Sahani D, Sorensen AG, Thrall JH. Imaging angiogenesis: applications and potential for drug development. J Natl Cancer Inst 2005;97:172–187. Crossref, MedlineGoogle Scholar
  • 8 Uyl-de Groot, CA, Giaccone G. Health economics: can we afford an unrestricted use of new biological agents in gastrointestinal oncology? Curr Opin Oncol 2005;17:392–396. Crossref, MedlineGoogle Scholar
  • 9 Liu G, Rugo H, Wilding G, et al. Dynamic contrast-enhanced magnetic resonance imaging as a pharmacodynamic measure of response after acute dosing of AG-013736, an oral angiogenesis inhibitor, in patients with advanced solid tumors: results from a phase I study. J Clin Oncol 2005;23:5464–5473. Crossref, MedlineGoogle Scholar
  • 10 Bremer C, Mustafa M, Bogdanov AJ, Ntziachristos V, Petrovsky A, Weissleder R. Steady-state blood volume measurements in experimental tumors with different angiogenic burdens: a study in mice. Radiology 2003;226:214–220. LinkGoogle Scholar
  • 11 Lewin M, Bredow S, Sergeyev N, Marecos E, Bogdanov AJ, Weissleder R. In vivo assessment of vascular endothelial growth factor-induced angiogenesis. Int J Cancer 1999;83:798–802. Crossref, MedlineGoogle Scholar
  • 12 Sipkins D, Cheresh D, Kazemi M, Nevin L, Bednarski M, Li K. Detection of tumor angiogenesis in vivo by alphaVbeta3-targeted magnetic resonance imaging. Nat Med 1998;4:623–626. Crossref, MedlineGoogle Scholar
  • 13 Kang HW, Josephson L, Petrovsky A, Weissleder R, Bogdanov A Jr. Magnetic resonance imaging of inducible E-selectin expression in human endothelial cell culture. Bioconjug Chem 2002;13:122–127. Crossref, MedlineGoogle Scholar
  • 14 Bredow S, Lewin M, Hofmann B, Marecos E, Weissleder R. Imaging of tumour neovasculature by targeting the TGF-beta binding receptor endoglin. Eur J Cancer 2000;36:675–681. Crossref, MedlineGoogle Scholar
  • 15 Huang P, McKee T, Jain R, Fukumura D. Green fluorescent protein (GFP)-expressing tumor model derived from a spontaneous osteosarcoma in a vascular endothelial growth factor (VEGF)-GFP transgenic mouse. Comp Med 2005;55:236–243. MedlineGoogle Scholar
  • 16 Wang Y, Iyer M, Annala A, Wu L, Carey M, Gambhir S. Non-invasive indirect imaging of vascular endothelial growth factor gene expression in a transgenic mouse model using bioluminescence imaging [abstr]. Mol Imaging 2005;4:315. Google Scholar
  • 17 Ntziachristos V, Ripoll J, Wang L, Weissleder R. Looking and listening to light: the evolution of whole-body photonic imaging. Nat Biotechnol 2005;23:313–320. Crossref, MedlineGoogle Scholar
  • 18 Ntziachristos V, Schellenberger E, Ripoll J, et al. Visualization of antitumor treatment by means of fluorescence molecular tomography with an annexin V-Cy5.5 conjugate. Proc Natl Acad Sci U S A 2004;101:12294–12299. Crossref, MedlineGoogle Scholar
  • 19 Graves EE, Weissleder R, Ntziachristos V. Fluorescence molecular imaging of small animal tumor models. Curr Mol Med 2004;4:419–430. Crossref, MedlineGoogle Scholar
  • 20 Montet X, Ntziachristos V, Grimm J, Weissleder R. Tomographic fluorescence mapping of tumor targets. Cancer Res 2005;65:6330–6336. Crossref, MedlineGoogle Scholar
  • 21 Callahan RJ, Bogdanov A Jr, Fischman AJ, Brady TJ, Weissleder R. Preclinical evaluation and phase I clinical trial of a 99mTc-labeled synthetic polymer used in blood pool imaging. AJR Am J Roentgenol 1998;171:137–143. Crossref, MedlineGoogle Scholar
  • 22 Alencar H, Mahmood U, Kawano Y, Hirata T, Weissleder R. Novel multi-wavelength microscopic scanner for mouse imaging. Neoplasia 2005;7:977–983. Crossref, MedlineGoogle Scholar
  • 23 Alencar H, King R, Funovics M, Stout C, Weissleder R, Mahmood U. A novel mouse model for segmental orthotopic colon cancer. Int J Cancer 2005;117:335–339. Crossref, MedlineGoogle Scholar
  • 24 Mentzel T, Brown L, Dvorak H, et al. The association between tumour progression and vascularity in myxofibrosarcoma and myxoid/round cell liposarcoma. Virchows Arch 2001;438:13–22. Crossref, MedlineGoogle Scholar
  • 25 Weissleder R, Bogdanov AJ, Tung C, Weinmann H. Size optimization of synthetic graft copolymers for in vivo angiogenesis imaging. Bioconjug Chem 2001;12:213–219. Crossref, MedlineGoogle Scholar
  • 26 Mordenti J, Thomsen K, Licko V, Chen H, Meng Y, Ferrara N. Efficacy and concentration-response of murine anti-VEGF monoclonal antibody in tumor-bearing mice and extrapolation to humans. Toxicol Pathol 1999;27:14–21. Crossref, MedlineGoogle Scholar
  • 27 Ntziachristos V, Tung C, Bremer C, Weissleder R. Fluorescence molecular tomography resolves protease activity in vivo. Nat Med 2002;8:757–760. Crossref, MedlineGoogle Scholar
  • 28 Yuan F, Dellian M, Fukumura D, et al. Vascular permeability in a human tumor xenograft: molecular size dependence and cutoff size. Cancer Res 1995;55:3752–3756. MedlineGoogle Scholar
  • 29 Satchi-Fainaro R, Puder M, Davies J, et al. Targeting angiogenesis with a conjugate of HPMA copolymer and TNP-470. Nat Med 2004;10:255–261. Crossref, MedlineGoogle Scholar

Article History

Published in print: 2007