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Prof. Gerhard ChristoforiProf. Gerhard Christofori

Institute of Biochemistry and GeneticsInstitute of Biochemistry and GeneticsDepartment of Clinical-Biological SciencesDepartment of Clinical-Biological Sciences

University of BaselUniversity of Basel

Angiogenesis as aAngiogenesis as a therapeutic targettherapeutic target

LectureLectureExperimentelle KrebsforschungExperimentelle Krebsforschung

SS 07SS 07

MultistageMultistage Tumorigenesis Tumorigenesis

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Multistage Colorectal CarcinogenesisMultistage Colorectal Carcinogenesis

Tumor angiogenesis Tumor angiogenesis

Bergers and Benjamin, 2002, Nat. Rev. Cancer

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Increased Increased microvessel microvessel density in tumorsdensity in tumors(for example (for example ductal ductal breast carcinoma)breast carcinoma)

Vasculogenesis/AngiogenesisVasculogenesis/Angiogenesis

Carmeliet, 2003

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Tumor angiogenesis in transplanted tumorsTumor angiogenesis in transplanted tumors

Weinberg, 2006

Genetic manipulation of miceGenetic manipulation of mice

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The Rip1Tag The Rip1Tag TransgeneTransgene

Hanahan, Nature, 1985

Rip1Tag2 Rip1Tag2 tumorigenesistumorigenesis

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Multistage Multistage Tumorigenesis Tumorigenesis in Rip1Tag2 Transgenic Micein Rip1Tag2 Transgenic Mice

““The The angiogenic angiogenic switchswitch””

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Cellular Events in Tumor Angiogenesis Cellular Events in Tumor Angiogenesis

Key Key Angiogenic Angiogenic FactorsFactors

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Clinical Science www.Clinical Science www.clinsciclinsci.org .org ClinClin. . SciSci. (2005) 109, 227-241. (2005) 109, 227-241

VEGF Family MembersVEGF Family Members

Vascular Endothelial Growth Factors and their Receptors Vascular Endothelial Growth Factors and their Receptors

Cross et al., TIBS, 2003

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Hemangioblast

Hematopoietic precursor

VEGFR-2

Alitalo 2001, Stacker 1999

Blood cells

Hematopoiesis

Hematopoietic cells Angioblast

Primary vascular plexus

VEGF-AVEGFR-1VEGFR-2

Vasculogenesis

Enlarged embryonic vasculature(arteries & veins)

VEGF-AVEGFR-1VEGFR-2VEGFR-3

Angiogenesis

EG-VEGFEndothelial

differentiation

„permeable blood vessels“in steroidogenic glands

„tight blood vessels“e.g. brain

Lymphangioblast

VEGF-C VEGF-D VEGFR-3

VEGF-C VEGF-D VEGFR-3

Lymphangiogenesis

prox-1

Lymphatic vessels

VEGFs VEGFs inin Vasculogenesis Vasculogenesis/Angiogenesis/Angiogenesis

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Clinical Science www.Clinical Science www.clinsciclinsci.org .org ClinClin. . SciSci. (2005) 109, 227-241. (2005) 109, 227-241

VEGFs VEGFs and theirand their ReceptorsReceptors

Chick CAM AssayChick CAM Assay

Chorio-Allantoic-MembraneChorio-Allantoic-Membrane+/- VEGF-A+/- VEGF-A

VEGF-Knock-outVEGF-Knock-outheterozygous lethal!heterozygous lethal!

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Hypoxia-induction of VEGF-A gene expressionHypoxia-induction of VEGF-A gene expression

Harris, 2001

HIF-1HIF-1αα regulation regulation

Harris, 2001

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Harris, 2001

Vascular Endothelial Growth FactorsVascular Endothelial Growth Factors

and their Receptorsand their Receptors

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TheThe Angiogenic Angiogenic SwitchSwitch

VEGF sequestered by ECM

VEGF released by MMP activity(mast cells,

Vascular Endothelial Growth Factor-AVascular Endothelial Growth Factor-A

Cross et al., TIBS, 2003

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Activation ofActivation ofVascular Endothelial Growth Factor-AVascular Endothelial Growth Factor-A

Ferrara et al., 2003

MMPs MMPs in breast (and other) tumorsin breast (and other) tumors

Egeblad and Werb, 2002

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Angiogenic Angiogenic Factors and the ECMFactors and the ECM

Sund et al., 2004

A Simplified Picture of Tumor Angiogenesis A Simplified Picture of Tumor Angiogenesis

VEGFs VEGF receptorsFGFs FGF receptorsAngiopoietins Tie-2 (Tie-1?)PDGF B PDGF-β receptorTGFβ TGFβ receptors

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AngiopoietinsAngiopoietins

Jones et al., 2001

VEGFs VEGFs and and AngiopoietinsAngiopoietins

Jones et al., 2001

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The Fine Balance of Angiogenesis Regulation The Fine Balance of Angiogenesis Regulation

Bergers and Benjamin, 2002, Nat. Rev. Cancer

Angiogenesis InhibitorsAngiogenesis Inhibitors

EndogenousEndogenousTherapeuticTherapeutic

chemicalschemicalsantibodiesantibodiespeptides/proteinspeptides/proteins

Folkman, 2004

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Angiogenesis InhibitorsAngiogenesis Inhibitors

Cilengitide

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Endogenous angiogenesis inhibitorsEndogenous angiogenesis inhibitors

Experimental Therapy in Rip1Tag2 MiceExperimental Therapy in Rip1Tag2 Mice

Interferon α/βTNP470AngiostatinEndostatinThrombospondinMMP inhibitorsCathepsin inhibitorsGlivec (imatinib

VEFR receptor inhibitors(PTK787,Sugen 6668, …)VEGF-Trap, FGF-TrapVEGF receptor antibodiesImmunoliposomesExendin-4 (GLP1R peptide)AEW471 (IGF1 receptor inhibitor)PDGF receptor inhibitors

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Bergers et al. Science 1999

Anti-Anti-Angiogenic Angiogenic Therapy in Rip1Tag2 MiceTherapy in Rip1Tag2 Mice

Weinberg, 2006

Anti-Angiogenic Anti-Angiogenic Therapy in Rip1Tag2 MiceTherapy in Rip1Tag2 Mice

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A selection of A selection of anti-angiogenic anti-angiogenic drugs approved drugs approved or or in clinical trialsin clinical trials

Approved for CRCfirst and second line

VEGF-A expression and anti-VEGF-A therapy (VEGF-A expression and anti-VEGF-A therapy (AvastinAvastin))

Borgstrom et al., 1999

Hanrahan et al., 2003

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Avastin Avastin in Colorectal Cancerin Colorectal Cancer

Hurwitz et al., 2004

Resistance to Resistance to anti-angiogenic anti-angiogenic therapy?therapy?

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Fibroblast Growth Factors and their Receptors Fibroblast Growth Factors and their Receptors

Soluble Receptor ConstructsSoluble Receptor Constructs

Compagni et al., Cancer Res. 2000

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VEGFs VEGFs and and FGFs FGFs are required for Tumor Angiogenesis:are required for Tumor Angiogenesis:Rip1Tag2Rip1Tag2 tumorigenesis tumorigenesis in vivoin vivo

Compagni et al., Cancer Res. 2000

A selection of A selection of anti-angiogenic anti-angiogenic drugs approved drugs approved or or in clinical trialsin clinical trials

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A selection of A selection of anti-angiogenic anti-angiogenic drugs approved drugs approved or or in clinical trialsin clinical trials

Maturation of Vessels Maturation of Vessels

Pietras and Hanahan, 2005

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Two Vascular Systems!Two Vascular Systems!

Jones et al., 2001

The Lymphatic SystemThe Lymphatic System

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Lymphatic vesselsLymphatic vessels

Papoutsi et al. Dev. Dyn. 2001

Lymphatic vessel development Lymphatic vessel development

Prox-1 as Prox-1 as master control gene?master control gene?

Oliver and Detmar, 2002

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ProxProx-1-induced lymphatic differentiation -1-induced lymphatic differentiation

Petrova et al., 2002

Tumor angiogenesis andTumor angiogenesis and lymphangiogenesis lymphangiogenesis

Vasculogenesis = De novo formation of blood vessels

Angiogenesis = Formation of blood vessels from pre-existing blood vesselsLymphangiogenesis = Formation of lymphatic vessels

Ruoslahti, 2002

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Lymphangiogenesis Lymphangiogenesis and angiogenesis in tumors and angiogenesis in tumors

Crnic et al., 2004

VEGF Family Members and their ReceptorsVEGF Family Members and their Receptors

ANGIOGENESIS LYMPHANGIOGENESIS

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Rip1VEGF-C

wt

ForcedForced Lymphangiogenesis Lymphangiogenesis in Rip1VEGF-C Mice in Rip1VEGF-C Mice

Mandriota et al., 2001

Rip1Tag2;Rip1VEGF-C

METLN

ForcedForced Lymphangiogenesis Lymphangiogenesis in Rip1Tag2 Mice in Rip1Tag2 Mice

Mandriota et al., 2001

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Anti-angiogenic Anti-angiogenic therapytherapy

• ± general mechanism in solid tumors

• no or low resistance

• defined targets

• no angiogenesis in adults, low side effects

• synergism with chemo- and radiotherapy

• anti-metastatic?

• efficacy?

• longterm treatment, side effects?

• resistance afterall?

• lymphangiogenesis - lymph node metastasis

• inflammation!

Reviews:

Carmeliet P. Angiogenesis in health and disease.Nat Med. 2003 Jun;9(6):653-60.

Alitalo K, Carmeliet P. Molecular mechanisms of lymphangiogenesis in health and disease.Cancer Cell. 2002 Apr;1(3):219-27.

Stacker SA, Achen MG, Jussila L, Baldwin ME, Alitalo K. Lymphangiogenesis and cancermetastasis. Nat Rev Cancer. 2002 Aug;2(8):573-83.

Bergers G, Benjamin LE. Tumorigenesis and the angiogenic switch.Nat Rev Cancer. 2003 Jun;3(6):401-10.

Ferrara N, Gerber HP, LeCouter J.The biology of VEGF and its receptors.Nat Med. 2003 Jun;9(6):669-76.

Ferrara N. VEGF and the quest for tumour angiogenesis factors. Nat Rev Cancer. 2002Oct;2(10):795-803.

Folkman J. Angiogenesis: an organizing principle for drug discovery? Nat Rev Drug Discov.2007 Apr;6(4):273-86.