Transcript angiogenesis

Special approaches of tumor
biology and chemotaxis
Orsolya Láng
2012.
TUMOR CELLS AND MIGRATION
PRIMARY TUMOR
Angiogenezis
Adhesion
METASTASIS
CELL and CELL CYCLE
Apoptosis
Chemokines
Growth
factors
Regulatory
proteins
Adhesion
molecules
TUMOR CELL
CELL KINETICS
Doubling time of the tumor volume (Td)
Time of the Cell cycle (Tc):
Tc= Ts / Li
Lymphoma
48 h
Lung cancer
Usually 15-125 h
108 h
Lymphoma 4 weeks
Colon adenoma 90 weeks
Usually 18-200 days
Ts: S phase
Li: labeling index
(proportoin of cells in S phase)
Growth fraction(GF):
GF=P / (P+Q’)
P: number of the mitotic cells
Q: number of the cells in interphase
Rate of the cell loss ():
= 1-Tpd / Td Tpd= *Ts/Li
Tpd: Potential tumor volume doubling time
Td: tumor volume doubling time
Volume of the tumor tissue
~10 division =*1000 cell number increase (210 =1024)
~20 division= 106 cells = 1 mg= 1 mm3
~30 division= 109 cells = 1 g= 1 cm3
~40 division= 1012 cells = 1 kg
1 tumor cell
~27 division
= 0,1cm3
Earliest time of
diagnosis
~30-33,25 division
=1-10 cm3
Time of the clinical
symptomes /
diagnosis
~40 division
= 1012cell
Fatal
BIOLOGY OF THE
TUMORPROGRESSION
Tumorigenesis
Exogen and endogen factors
Genom instability
Activation of the oncogene
Inactivation of tumorsuppressors
Growth rate
De-Differentation
Invazivity
Ectopic survival capacity
Epithelial
cell
Hiperplastic
adenoma
inhibition
Displatic
Carcinoma in situ
Invasive and metastasis
carcinoma
Local and systemic factors
acceleration
Important steps of tumor progression
Transformation of the microenvironment:
stromal cells,
ECM components,
proteolytic degradation
Induction of the angiogenesis
Escaping from immune-mediated rejection
Formation of metastasis
MICROENVIRONMENT – STROMAL CELLS
Cell types:
fibroblasts, myofibroblasts, endothelial cells, lymphocytes,
macrophages
Function:
host defence
!
!
MALT - B cell helps to maintain lymphomas
Growth factors are released by the stromal cells (VEGFangiogenesis)
ANGIOGENESIS
Hypoxia  formation of new vessels, proliferation of the endothelial cells
Types:
vessels
 OEDEMA,
arteriovenous shunts
decresed
„dead end”
blood flow
/lack of smooth muscle , weak vessel wall, irregular shape(insuficient
endothelial cell and basement membrane layers)/
sinuses /wall is formed by tumor cells/
Venous circulation
VEGF 
induces angiogensis
increases permeability
Lack of lymphatic vessels
Strategies that tumors use to escape from
immune-mediated rejection are:
To decrease the antigen expression
To inhibit the immune-reactive cells:
degrade the chemoattractans
decrease their cell adhesion
inhibite their phagocytotic activity
METASTATIC CASCADE
Tumor cell
Angiogenesis
VEGF
Angiogenin
FGF
Primary
tumor
Metastasis
Angiogenesis
Local invasion
ECM
Adhesion
Proteolysis
Migration
Adhesion
Proteolysis
Migration
Intravasation
circulation
spreading
Extravasation
INVASION
In situ carcinoma
DECREASED CELL
ADHESION,
INCREASED MOTILITY
ECM proteolysis
METASTATIC CASCADE
Tumor cell
Angiogenesis
VEGF
Angiogenin
FGF
Primary
tumor
Angiogenesis
Local invasion
ECM
Adhesion
Proteolysis
Migration
Adhesion
Proteolysis
Migration
Intravasation
Metastasis
circulation
spreading
Extravasation
CELL ADHESION
Significant change in cell-cell and cell-ECM
interactions
Molecules:
selectins
integrins
immunoglobulin superfamily
cadherins
catenins
SELECTINS
Cell-cel junctions
Types:
E- endothelial cells
P- trombocytes
L- leukocytes
Extracellular C-lectin domain
Ca2+ dependent anchorage
It binds Sialyl-Lex carbohydrates
„ROLLING”
! Tumor cells express increased amount of sialil-Lex or -Lea
D
R
INTEGRINS
G

Transmembrane receptors

Form cell-ECM interaction
8 , 14  subunites ~20 heterodimer
Ca2+, Mg2+ dependent anchorage
„RGD” sequence is the specific substrate
Signalling:
outside-in – signalling
inside-out – adhesion
Increased expression of integrins promotes angiogenesis and helps to
bind MMPs at the cell surface
EXTRAVASATION, ATTACHMENT
Integrin or celladhesion regulated signalling
pathways
ECM
integrin
PTEN
RAC
FAK
ILK
PI(3)K
SHC
GRB2/SOS
CDC42
PKB/AKT
BAD
apoptosis
RAS
RAF
MEK
MAPK
GSK3
Ciklin D1
cellcycle
-catenin
gene expression
motility
cellproliferation
Integrin or celladhesion regulated signalling
pathways
ECM
integrin
PTEN
RAC
FAK
ILK
PI(3)K
SHC
GRB2/SOS
CDC42
PKB/AKT
BAD
apoptsis
RAS
RAF
MEK
MAPK
GSK3
Ciklin D1
cellcycle
-katenin
gene expression
motility
cellproliferation
Molecular partners of the integrins
Cytoskeletal components:
actinin, talin,F- actin, filamin
Adaptors:
rack 1, ICAP-1
Calcium binding proteins:
CIB, calreticulin
Protein kinases:
pp125FAK, p59 ILK
Membrane proteins:
CD9, CD16,CD47…
caveolin, urokinase-plazminogen-activator receptor
Ligands in ECM:
collagen, laminin, fibronectin, fibrinogen, von Willebrand
factor, osteopontin, elastin
IMMUNGLOBULIN SUPERFAMILY
has 5 Ig-like domains at the extracellular region
forms cell-cell junction
interacts with integrins
VCAM - 41, PECAM - v3
takes essential part in extravasation
!
!
!
!
Over expression of ICAM-1, MUC18  increased inavsion
Down-regulation of VCAM-1  increased metastatic potential
(faster detachment)
CADHERIN
Is a transmembrane glycoprotein
Forms homophyl cell-cell junctions
Ca2+ dependent anchorage
Classical types:
E- epithelial
P- placenta
N- neural,
Intracellular part interacts with catenins to connect aktin
filaments
!
Increased expression  invasion
CATENIN
Is an intracellular molecule
Fixes cadherins to F-actin
!
!
Catenin expression is often decreased in carcinomas
-catenin binds to the az APC gén termékéhez
Factors influencing the metastatic potential
of the melanoma cells
Adhesion
molecules
Signal
pathways
Increases
Ihibits
N-Cadherin
E-Cadherin
B-Catenin
aE-Catenin
SrC
cMET
Ras
FGFR
PTEN
METASTATIC CASCADE
Tumor cell
Angiogenesis
Primary
tumor
Local invasion
ECM
VEGF
Angiogenin
FGF
Integrins
cadherins
Selectins
CAM
Angiogenesis
Adhesion
Proteolysis
Migration
Adhesion
Proteolysis
Migration
Intravasation
Metastasis
Circulation
spreading
Extravasation
PROTEOLYSIS
Components of the basement membrane(BM) and ECM: IV collagen,
laminin, proteoglycanes
Tumorcells (stromal cells) secrete proteases
Cathepsin
Matrix metalloproteinase (MMP)
Plazmin, tPA ,Urokinase (plasminogen activator inhibitor 1&2)
TIMP
INVASION
Tissue inhibitor of metalloproteinases
MATRIX METTALLOPROTEINASES (MMP)
Zn2+ dependent endopeptidase (MMP28)
ECM degradation – tissue remodelling
Interstitial collagenase (MMP2)
Stromalysin
Gelatinase (MMP9)
Membrane type MMP
Produces biologically active molecules
MOLECULAR STRUCTURE OF THE MATRIX METTALLOPROTEINASES
SUBSTRATE OF TIMP
MMP/TIMP EXPRESSION IN BREAST CANCER
MMP – TUMORPROGRESSION
?!?
METASTATIC CASCADE
Tumor cell
Angiogenesis
Primary
tumor
Local invasion
ECM
Adhesion
Proteolysis
Migration
Intravasation
VEGF
Angiogenin
FGF
Integrins
cadherins
Selectins
CAM
MMP/TIMP
Cathepsin
Plasminogen
Circulation
spreading
Metastasis
Angiogenesis
Adhesion
Proteolysis
Migration
Extravasation
MIGRATORY MECHANISMS IN TUMOR
Small-cell
lung cancer
FORMS OF MIGRATORY ADAPTATION
2D –3D MIGRATIONS
STEPS OF 3D
MIGRATION
1. Pseudopod protrusion
2. Formation of focal contact
3. Focal ECM
proteolysis
4. Actomyosin contraction
5. Detachment
Cell-cell interactions visualized in
tumorigenesis
METASTATIC CASCADE
Tumor cell
Angiogenesis
Primary
tumor
Local invasion
ECM
Adhesion
Proteolysis
Migration
Intravasation
VEGF
Angiogenin
FGF
Integrins
cadherins
Selectins
CAM
MMP/TIMP
Cathepsin
Plasminogen
Metastasis
Angiogenesis
Adhesion
Proteolysis
Migration
AMF/gp78
Autotaxin
HGF/c-MET
Circulation
spreading
Extravasation
HEMATOGENIC DISSEMINATION
!! Tumor markers e.g. cytokeratin, mucin
EXTRAVASATION
Attachment
Migration
?
LOCALISATION OF THE METASTASIS
CHEMOKINES – TISSUE SPECIFIC LOCALISATION
motility
?
adhesion