Special approaches of tumor biology and chemotaxis
Orsolya Láng 2012.
TUMOR CELLS AND MIGRATION
METASTASISPRIMARY TUMOR
AngiogenezisAdhesion
CELL and CELL CYCLE
Growth factors
Adhesion Adhesion moleculesmolecules
ChemokineChemokiness
Regulatory Regulatory proteinsproteins
ApoptosisApoptosis
TUMOR CELL
CELL KINETICS
Doubling time of the tumor volume (Td)
Time of the Cell cycle (Tc):Tc= Ts / Li
Ts: S phaseLi: labeling index
(proportoin of cells in S phase)
Growth fraction(GF):GF=P / (P+Q’)
P: number of the mitotic cellsQ: number of the cells in interphase
Rate of the cell loss ():= 1-Tpd / Td Tpd= *Ts/Li
Tpd: Potential tumor volume doubling timeTd: tumor volume doubling time
Lymphoma 48 hLung cancer 108 h Usually 15-125 h
Lymphoma 4 weeksColon adenoma 90 weeksUsually 18-200 days
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 ~30-33,25 division=1-10 cm3
Time of the clinical symptomes / diagnosis
~27 division= 0,1cm3
Earliest time of diagnosis
~40 division= 1012cellFatal
BIOLOGY OF THE TUMORPROGRESSION
Exogen and endogen factorsGenom instability
Activation of the oncogeneInactivation of tumorsuppressors
Epithelialcell
Hiperplasticadenoma
DisplaticCarcinoma in situ
Invasive and metastasis carcinoma
Local and systemic factorsinhibition acceleration
Growth rate
Ectopic survival capacity
Invazivity
De-Differentation
Tumorigenesis
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 (VEGF-angiogenesis)
ANGIOGENESISHypoxia formation of new vessels, proliferation of the endothelial cellsTypes: vesselsarteriovenous shunts„dead end”/lack of smooth muscle , weak vessel wall, irregular shape(insuficient endothelial cell and basement membrane layers)/sinuses /wall is formed by tumor cells/Venous circulationVEGF induces angiogensisincreases permeabilityLack of lymphatic vessels
OEDEMA, decresed blood flow
Strategies that tumors use to escape from immune-mediated rejection are:
To decrease the antigen expressionTo inhibit the immune-reactive cells:
degrade the chemoattractansdecrease their cell adhesioninhibite their phagocytotic activity
Angiogenesis
Local invasion
ECMAdhesionProteolysisMigration
Intravasation
Extravasation
circulation
Metastasis
Tumor cell
Primary tumor
AdhesionProteolysisMigration
Angiogenesis
VEGFAngiogeni
nFGF
spreading
METASTATIC CASCADE
INVASION
In situ carcinoma
DECREASED CELL ADHESION, INCREASED MOTILITY
ECM proteolysis
Angiogenesis
Local invasion
ECMAdhesionProteolysisMigration
Intravasation
Extravasation
circulation
Metastasis
Tumor cell
Primary tumor
AdhesionProteolysisMigration
Angiogenesis
VEGFAngiogeni
nFGF
spreading
METASTATIC CASCADE
CELL ADHESION
Significant change in cell-cell and cell-ECM interactionsMolecules:selectinsintegrinsimmunoglobulin superfamily cadherins catenins
SELECTINS
Cell-cel junctionsTypes:E- endothelial cellsP- trombocytesL- leukocytesExtracellular C-lectin domain Ca2+ dependent anchorage It binds Sialyl-Lex carbohydrates
„ROLLING”
! Tumor cells express increased amount of sialil-Lex or -Lea
INTEGRINS
Transmembrane receptorsForm cell-ECM interaction8 , 14 subunites ~20 heterodimerCa2+, Mg2+ dependent anchorage„RGD” sequence is the specific substrateSignalling: outside-in – signalling
inside-out – adhesionIncreased expression of integrins promotes angiogenesis and helps to bind MMPs at the cell surfaceEXTRAVASATION, ATTACHMENT
DG
R
Integrin or celladhesion regulated signalling pathways
cellproliferation
PTEN
RAC PI(3)K
CDC42
integrin
ECM
ILK
-cateninCiklin D1BAD
PKB/AKT
FAK
RASRAFMEKMAPK
GSK3
motilitygene expression
cellcycleapoptosis
SHCGRB2/SOS
Integrin or celladhesion regulated signalling pathways
integrin
ECM
ILK
-kateninCiklin D1BAD
PKB/AKT
FAK
cellproliferation
RASRAFMEKMAPK
GSK3
motilitygene expression
cellcycleapoptsis
SHCGRB2/SOS
PTEN
RAC PI(3)K
CDC42
Molecular partners of the integrinsCytoskeletal components:actinin, talin,F- actin, filaminAdaptors:rack 1, ICAP-1Calcium binding proteins:CIB, calreticulinProtein kinases:pp125FAK, p59 ILKMembrane proteins:CD9, CD16,CD47…caveolin, urokinase-plazminogen-activator receptorLigands in ECM:collagen, laminin, fibronectin, fibrinogen, von Willebrand factor, osteopontin, elastin
IMMUNGLOBULIN SUPERFAMILY
has 5 Ig-like domains at the extracellular regionforms cell-cell junction interacts with integrins
VCAM - 41, PECAM - v3
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 glycoproteinForms homophyl cell-cell junctionsCa2+ dependent anchorageClassical types: E- epithelial
P- placentaN- neural,
Intracellular part interacts with catenins to connect aktin filaments
! Increased expression invasion
CATENINCATENIN
Is an intracellular moleculeFixes cadherins to F-actin
! Catenin expression is often decreased in carcinomas
! -catenin binds to the az APC gén termékéhez
Increases
N-CadherinB-Catenin
SrCRas
Ihibits
E-CadherinaE-Catenin
cMETFGFRPTEN
Adhesionmolecules
Signal pathways
Factors influencing the metastatic potential of the melanoma cells
Angiogenesis
Local invasion
ECMAdhesionProteolysisMigration
Intravasation
Extravasation
Circulation
Metastasis
Tumor cell
Primary tumor
AdhesionProteolysisMigration
Angiogenesis
VEGFAngiogeni
nFGF
spreading
METASTATIC CASCADE
IntegrinscadherinsSelectins
CAM
PROTEOLYSISComponents of the basement membrane(BM) and ECM: IV collagen, laminin, proteoglycanesTumorcells (stromal cells) secrete proteasesCathepsinMatrix metalloproteinase (MMP)Plazmin, tPA ,Urokinase (plasminogen activator inhibitor 1&2)TIMP
INVASION
Tissue inhibitor of metalloproteinases
MATRIX METTALLOPROTEINASESMATRIX METTALLOPROTEINASES (MMP)(MMP)
MOLECULAR STRUCTURE OF THE MATRIX MOLECULAR STRUCTURE OF THE MATRIX METTALLOPROTEINASESMETTALLOPROTEINASES
SUBSTRATE OF TIMP
MMP/TIMP EXPRESSION IN BREAST MMP/TIMP EXPRESSION IN BREAST CANCERCANCER
MMP – TUMORPROGRESSION?!?
Angiogenesis
Local invasion
ECMAdhesionProteolysisMigration
Intravasation
Extravasation
Circulation
Metastasis
Tumor cell
Primary tumor
AdhesionProteolysisMigration
Angiogenesis
VEGFAngiogeni
nFGF
spreading
METASTATIC CASCADE
IntegrinscadherinsSelectins
CAM
MMP/TIMPCathepsin
Plasminogen
MIGRATORY MECHANISMS IN TUMOR
Small-cell lung cancer
FORMS OF MIGRATORY ADAPTATION
2D –3D MIGRATIONS
STEPS OF 3D MIGRATION
1. Pseudopod protrusion2. Formation of focal contact3. Focal ECM proteolysis4. Actomyosin contraction5. Detachment
Cell-cell interactions visualized in tumorigenesis
Angiogenesis
Local invasion
ECMAdhesionProteolysisMigration
Intravasation
Extravasation
Circulation
Metastasis
Tumor cell
Primary tumor
AdhesionProteolysisMigration
Angiogenesis
VEGFAngiogeni
nFGF
spreading
METASTATIC CASCADE
IntegrinscadherinsSelectins
CAM
MMP/TIMPCathepsin
Plasminogen
AMF/gp78AutotaxinHGF/c-MET
!! Tumor markers e.g. cytokeratin, mucin
HEMATOGENIC DISSEMINATION
EXTRAVASATION
?
Attachment
Migration
LOCALISATION OF THE METASTASIS
CHEMOKINES – TISSUE SPECIFIC LOCALISATION
adhesion
mot
ility
?