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100
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English
Documents
2006
Écrit par
Julie Daffos
Publié par
goethe_universitat_frankfurt_am_main
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100
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English
Ebook
2006
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Publié par
Publié le
01 janvier 2006
Nombre de lectures
55
Langue
English
Poids de l'ouvrage
2 Mo
Publié par
Publié le
01 janvier 2006
Nombre de lectures
55
Langue
English
Poids de l'ouvrage
2 Mo
Regulation of Microsomal Prostaglandin E2 Synthase by
Cyclopentenone Prostaglandins in Colon Cancer Cells
Dissertation
zur Erlangung des Doktorgrades
der Naturwissenschaften
Vorgelegt beim Fachbereich für
Chemische und Pharmazeutische Wissenschaften
der Johann Wolfgang Goethe-Universität
in Frankfurt am Main
von
Yulyana Yudina
aus Kharkov, Ukraine
Frankfurt am Main (2005)
(D 30)
Vom Fachbereich Chemische und Pharmazeutische Wissenschaften der
Johann-Wolfgang-Goethe Universität als Dissertation angenommen.
Dekan: Prof. Dr. Harald Schwalbe
Gutachter: Prof. Dr. Dieter Steinhilber
Prof. Dr. Dr. Jürgen Stein
Datum der Disputation:
1
To my parents,
2
Table of contents:
Abbrevations................................................................................................. 1
1 Introduction ............................................................................................... 4
1.1.1 Biological functions of prostaglandin E ........................................... 6 2
1.1.2 Prostaglandin E and cancer .............................................................. 7 2
1.2 Cyclopentenone prostaglandins ............................................................ 9
∆12,141.2.1 15-deoxy- -PGJ .......................................................................... 10 2
1.3 Enzymes involved in prostaglandin biosynthesis .............................. 12
1.3.1 Phospholipase A enzymes................................................................ 12 2
1.3.2 Cyclooxygenase enzymes .................................................................. 13
1.4 Prostaglandin E synthases ................................................................... 15
1.4.1 Cytosolic prostaglandin E synthase................................................. 15
1.4.2 Microsomal prostaglandin E synthase-1......................................... 16
1.4.3 Microsomal prostaglandin E synthase -2........................................ 17
2. Aim of the present investigation ........................................................... 20
3. Materials and Methods .......................................................................... 21
3.1.1 Chemicals ........................................................................................... 21
3.1.2 Antibodies 24
3.1.3 Mediums and Solutions..................................................................... 25
3.1.4 Cell lines ............................................................................................. 26
3.1.5 Instruments ........................................................................................ 27
3.1.6 Software.............................................................................................. 28
3.2.1 Cell culture......................................................................................... 28
3.2.2 Cell proliferation ............................................................................... 28
3.2.3 Cytotoxicity ........................................................................................ 29
3.2.4 Preparation of cellular fractions...................................................... 29
3.2.5 Analysis of mRNA levels using RT-PCR ........................................ 29
3.2.6 Immunoblot analysis ......................................................................... 30
3
3.2.7 PGES enzyme assay........................................................................... 31
3.2.8 Measurement of intracellular calcium level ................................... 31
3.2.9 Statistics.............................................................................................. 32
4. Results...................................................................................................... 33
4.1.1 Effect of 15d-PGJ on gene expression of the enzymes of 2
prostaglandin E2 synthesis ........................................................................ 33
4.1.2 15d-PGJ decreases mPGES-2 protein expression......................... 35 2
4.1.3 15d-PGJ reduces mPGES-2 enzyme activity................................. 38 2
4.2.1 Decreased expression of mPGES-2 in response to 15d-PGJ 2
treatment is PPAR γ independent.............................................................. 39
4.2.2 15d-PGJ does not affect mPGES-2 expression via cell surface 2
receptors ...................................................................................................... 43
4.2.3 The role of cyclopentenone ring structure in the down-regulation
of mPGES-2 expression.............................................................................. 45
4.2.4 Cyclopentenone prostaglandins induce oxidative stress................ 48
4.3.1 The effect of 15d-PGJ on cell growth............................................. 51 2
4.3.2 The implication of PGE formation in cell proliferation............... 52 2
5. Discussion ................................................................................................ 54
5.1 The role of mPGES-2 in colon cancer and its down-regulation by
anti-tumour cyclopentenone prostaglandin, 15d-PGJ . ......................... 54 2
5.2 The regulation of mPGES-2 by cyclopentenone prostaglandins is
independent of nuclear or membrane receptors activation, but may be
mediated by covalent binding of the cyclopentenone ring to cysteine
residues on signalling molecules or via a redox-dependent mechanism.
...................................................................................................................... 58
6. Summary ................................................................................................. 65
7. Zusammenfassung ............................... Fehler! Textmarke nicht definiert.
8. References ............................................................................................... 74
9. Appendix 90
4
10. Curriculum vitae .................................................................................. 91
11. Acknowledgements............................................................................... 93
5
Abbrevations
12,1415d-PGJ 15-deoxy- ∆ -prostaglandin J2 2
AAArachidonic acid
ACFAberrantcryptfoci
AOM Azoxymethane
AP-2Activator protein-2
APC Adenomatous polyposis coli
ATM Ataxia-telangectasia mutated kinase
ATP Adenosine triphosphate
cDNA Complementary deoxyribonucleic acid
COX Cyclooxygenase
cPGES Cytosolic prostaglandin E synthase
cPLA Cytosolic phospholipase A
cAMP Cyclic adenosine monophosphate
CRE cAMP response element
CRTH2 Chemoattractant receptor–homologous molecule expressed on TH2 cells
DEPCDiethylpyrocarbonate
DMEM Dulbecco’s modified Eagle medium
dNTPs Deoxyribonucleotide triphosphates
DTTDithiothreitol
ECACC European Animal Cell Culture Collection
EGFR Epidermal growth factor receptor
Egr-1 Early growth response
EIA Enzyme immunoassay
EREndoplasmicreticulum
ERK1/2 Extracellular signal-regulated kinase1/2
1
FBS Foetal Bovine serum
FLAP 5-lipoxygenase-activating protein
Fura-2/AM Fura-2 acetoxymethyl ester
GAPDHGlyceraldehyde 3-phosphate dehydrogenase
GSH Glutathione
H-Ras Homologous to the oncogene of the Harvey rat sarcoma virus
HSA Human serum albumin
HSF-1 Heat shock transcription factor 1
HSP Heat shockprotein
IMN Indomethacin
IP3Inositol(1,4,5)-trisphosphate
iPLA Intracellular phospholipase A
JAK Janus protein kinase
JNK c-jun N-terminal kinase
LDHLactatedehydrogenase
LTLeukotriene
MAPEG Membrane Associated Proteins in Eicosanoid and Glutathione metabolism
MAPK Mitogen-activated protein kinases
MGST1-L1 Membrane-bound glutathione S-transferase 1-like-1
Min Multiple intestinal neoplasms
mPGES Microsomal prostaglandin E synthase
mRNA Messenger ribonucleic acid
NAC N-acetylcysteine
NF-IL-6 Nuclear factor for interleukin-6
NF- κB Nuclear factor-kappa B
NSAID Non-steroidal anti-inflammatory drugs
2
PBS Posphate buffered saline
PGProstaglandin
PGT Prostaglandintransporter
PKProtein kinase
PPAR Peroxisomeproliferator-activated receptor
PPREPPAR-response element
ROS Reactive oxygen species
RT-PCR Reverse transcription-polymerase chain reaction
RXR Retinoid X receptor
SAPK Stress-activated protein kinases
SDS-PAGE Sodium dodecylsulfate polyacrylamide gel electrophoresis
Sp1 Specificity protein 1
sPLA Secretory phospholipase A
TBS-T Tween Tris Base Saline
TxThromboxane
VEGFVascularendothelial growth factor
3
INTRODUCTION
1 Introduction
1.1 Prostaglandins
Prostaglandins, thromboxanes and leukotrienes, collectively referred to as
‘eicosanoids’, are the cyclooxygenase (C