Molecular Imaging of Temporal Dynamics and Spatial Heterogeneity of Hypoxia-Inducible Factor-1 Signal Transduction Activity in Tumors in Living Mice

Tumor hypoxia is a spatially and temporally heterogeneous phenomenon, which results from several tumor and host tissue-specific processes. To study the dynamics and spatial heterogeneity of hypoxia-inducible factor-1 (HIF-1)-specific transcriptional activity in tumors, we used repetitive noninvasive positron emission tomography (PET) imaging of hypoxia-induced HIF-1 transcriptional activity in tumors in living mice. This approach uses a novel retroviral vector bearing a HIF-1–inducible “sensor” reporter gene (HSV1-tk/GFP fusion) and a constitutively expressed “beacon” reporter gene (DsRed2/XPRT). C6 glioma cells transduced with this multireporter system revealed dose-dependent patterns in temporal dynamics of HIF-1 transcriptional activity induced by either CoCl2 or decreased atmospheric oxygen concentration. Multicellular spheroids of C6 reporter cells developed a hypoxic core when >350 μm in diameter. 18F-2′-fluoro-2′deoxy-1β-D-arabionofuranosyl-5-ethyl-uracil (FEAU) PET revealed spatial heterogeneity of HIF-1 transcriptional activity in reporter xenografts in mice as a function of size or ischemia-reperfusion injury. With increasing tumor diameter (>3 mm), a marked increase in HIF-1 transcriptional activity was observed in the core regions of tumors. Even a moderate ischemia-reperfusion injury in small C6 tumors caused a rapid induction of HIF-1 transcriptional activity, which persisted for a long time because of the inability of C6 tumors to rapidly compensate acute changes in tumor microcirculation.

[1]  R. Henriksson,et al.  Spatial Expression of VEGF-A in Human Glioma , 2002, Journal of Neuro-Oncology.

[2]  D. Hanahan,et al.  Patterns and Emerging Mechanisms of the Angiogenic Switch during Tumorigenesis , 1996, Cell.

[3]  Sanjiv S Gambhir,et al.  Indirect monitoring of endogenous gene expression by positron emission tomography (PET) imaging of reporter gene expression in transgenic mice. , 2002, Molecular imaging and biology : MIB : the official publication of the Academy of Molecular Imaging.

[4]  R. Mulligan,et al.  A stable human-derived packaging cell line for production of high titer retrovirus/vesicular stomatitis virus G pseudotypes. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[5]  J Humm,et al.  Imaging transcriptional regulation of p53-dependent genes with positron emission tomography in vivo , 2001, Proceedings of the National Academy of Sciences of the United States of America.

[6]  K Groebe,et al.  On the relation between size of necrosis and diameter of tumor spheroids. , 1996, International journal of radiation oncology, biology, physics.

[7]  A. Wilks,et al.  Inhibition of growth of C6 glioma cells in vivo by expression of antisense vascular endothelial growth factor sequence. , 1996, Cancer research.

[8]  Jiping Zeng,et al.  Involvement of caspase‐3 and p38 mitogen‐activated protein kinase in cobalt chloride‐induced apoptosis in PC12 cells , 2002, Journal of neuroscience research.

[9]  L. Kunz-Schughart,et al.  Proliferative activity and tumorigenic conversion: impact on cellular metabolism in 3-D culture. , 2000, American journal of physiology. Cell physiology.

[10]  L. Ellis,et al.  Insulin-like Growth Factor 1 Induces Hypoxia-inducible Factor 1-mediated Vascular Endothelial Growth Factor Expression, Which is Dependent on MAP Kinase and Phosphatidylinositol 3-Kinase Signaling in Colon Cancer Cells* , 2002, The Journal of Biological Chemistry.

[11]  P. Sutphin,et al.  Role of Prolyl Hydroxylation in Oncogenically Stabilized Hypoxia-inducible Factor-1α* , 2002, The Journal of Biological Chemistry.

[12]  J. Milbrandt,et al.  In Vitro and In Vivo Characterization of a Dual-Function Green Fluorescent Protein–HSV1-Thymidine Kinase Reporter Gene Driven by the Human Elongation Factor 1α Promoter , 2002, Molecular imaging.

[13]  M. Gassmann,et al.  Oxygen(es) and the hypoxia-inducible factor-1. , 1997, Biological chemistry.

[14]  D. Ferriero,et al.  Regulation of hypoxia-inducible factor 1α and induction of vascular endothelial growth factor in a rat neonatal stroke model , 2003, Neurobiology of Disease.

[15]  A. Jacobs,et al.  Functional coexpression of HSV-1 thymidine kinase and green fluorescent protein: implications for noninvasive imaging of transgene expression. , 1999, Neoplasia.

[16]  H. Klocker,et al.  Increased growth factor production in a human prostatic stromal cell culture model caused by hypoxia , 2003, The Prostate.

[17]  Y. Kan,et al.  A hypoxia-regulated adeno-associated virus vector for cancer-specific gene therapy. , 2001, Neoplasia.

[18]  J. Tonn,et al.  Microtumor growth initiates angiogenic sprouting with simultaneous expression of VEGF, VEGF receptor-2, and angiopoietin-2. , 2002, The Journal of clinical investigation.

[19]  R. Blasberg,et al.  Development of a new reporter gene system--dsRed/xanthine phosphoribosyltransferase-xanthine for molecular imaging of processes behind the intact blood-brain barrier. , 2003, Molecular imaging.

[20]  G Holtermann,et al.  Influence of glucose on metabolism and growth of rat glioma cells (C6) in multicellular spheroid culture , 1992, International journal of cancer.

[21]  S. Larson,et al.  Imaging TCR-dependent NFAT-mediated T-cell activation with positron emission tomography in vivo. , 2001, Neoplasia.

[22]  R. Del Maestro,et al.  Implantation of C6 astrocytoma spheroid into collagen type I gels: invasive, proliferative, and enzymatic characterizations. , 1997, Journal of neurosurgery.

[23]  J. Caro,et al.  Hypoxia-inducible factor 1alpha (HIF-1alpha) protein is rapidly degraded by the ubiquitin-proteasome system under normoxic conditions. Its stabilization by hypoxia depends on redox-induced changes. , 1997, The Journal of biological chemistry.

[24]  Sanjiv S Gambhir,et al.  Molecular engineering of a two-step transcription amplification (TSTA) system for transgene delivery in prostate cancer. , 2002, Molecular therapy : the journal of the American Society of Gene Therapy.

[25]  G. Semenza,et al.  Purification and Characterization of Hypoxia-inducible Factor 1 (*) , 1995, The Journal of Biological Chemistry.

[26]  R. Blasberg,et al.  Imaging the expression of transfected genes in vivo. , 1995, Cancer research.

[27]  J. Bading,et al.  Preclinical evaluation of the penciclovir analog 9-(4-[(18)F]fluoro-3-hydroxymethylbutyl)guanine for in vivo measurement of suicide gene expression with PET. , 2001, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[28]  G. Semenza.  HIF-1: mediator of physiological and pathophysiological responses to hypoxia. , 2000, Journal of applied physiology.

[29]  A. Ullrich,et al.  Up-regulation of vascular endothelial growth factor and its cognate receptors in a rat glioma model of tumor angiogenesis. , 1993, Cancer research.

[30]  L. Poellinger,et al.  Redox-Regulated Recruitment of the Transcriptional Coactivators CREB-Binding Protein and SRC-1 to Hypoxia-Inducible Factor 1α , 2000, Molecular and Cellular Biology.

[31]  G. Semenza,et al.  Hypoxia Response Elements in the Aldolase A, Enolase 1, and Lactate Dehydrogenase A Gene Promoters Contain Essential Binding Sites for Hypoxia-inducible Factor 1* , 1996, The Journal of Biological Chemistry.

[32]  Wei Li,et al.  Noninvasive imaging of protein–protein interactions in living animals , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[33]  J. Folkman.  Tumor angiogenesis: therapeutic implications. , 1971, The New England journal of medicine.

[34]  S. Elledge,et al.  Rbx1, a component of the VHL tumor suppressor complex and SCF ubiquitin ligase. , 1999, Science.

[35]  R G Blasberg,et al.  Tumor growth modulation by sense and antisense vascular endothelial growth factor gene expression: effects on angiogenesis, vascular permeability, blood volume, blood flow, fluorodeoxyglucose uptake, and proliferation of human melanoma intracerebral xenografts. , 1998, Cancer research.