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Ivan Hirsch
Institut de Cancérologie de Marseille, UMR 599 INSERM
Institut Paoli-Calmettes
Université de la Méditerranée
27, boulevard Lei Roure
13009 MARSEILLE (France)
Phone : +33-(0)4-91 758415
Fax : +33-(0)4-91 260364
Email : [email protected]
Web site: http://u119.marseille.inserm.fr/
Hépatite C et le système immunitaire
Réplication virale
Infection chronique
Immunité innée
Interférons du type I
Cellules dendritiques plasmacytoïdes
Cancer hépatocellulaire
Familles de virus à ARN humains et animaux
polari
té
ARN
géno mique
taille
(kb)
ARNm
+
sb
"
Un
7.28.4
Taille de
géno me
"
"
Un
"
"
Un
Un
"
Diploide
4-10
"
sb
"
"
Un
16-20
Une
protéine
"
"
"
7-8 segments
+/-sb
"
Un
10-12
Un
Un
Enzyme s
dans le
virion
-
Protéine
-
picornaviridae
Entero-: poliomyélite, CardioHepato-: hépatite A, Rhino-
-
"
+
flaviviri dae
-
-
+
alphaviridae
hépatite C, fièvres hémorragiques: fièvre
jaune, virus de la dengue, encé phalite de
St.Louis
rubéole , virus de Sindbis (SV),
virus de la foret de Semliki (SFV)
-
-
+
-
coronaviridae
calicivirid ae
ARNt
+
retroviridae
Trans
criptase
+
+
-
+
rhabdoviridae
-
+
+
filoviridae
paramyxoviridae
Ebola, Marbu rg
"
+
+
orthomyxoviridae
grippe
"
"
+
+
ARNm
cellulaire
"
"
+
+
bunya viridae
arenaviridae
Fièvre hémorragique, Hantavirus
"
+
-
-
reoviridae
rotavirus, ma ladie fébrile
"
i nfantiles
+
-
-
birnaviridae
"bursal disease of chickens "
Subgéno
mique
"
"
14
3 segments
13-21
2 segments
10-14
“circ”
db
8-12
22-27
segme nts
"
2 segments
7
Soulignements : hЋpatites; maladies
RT,PR,IN
amorce
enveloppe Nom de famille
"comm on col d pneumonia"
hépatite E, gastroentérite
retro- (RSV), lenti- (VIH, SIV, HTLV),
spumavirus de la stomatite vésiculaire (VSV),
rage,
rougeole, oreillons, parainfluenza
Lassa, Machupo, virus de la Chorioméningite
lymp hocytaire (LCMV)
Familles
de àvirus
humains
et animaux
Familles de
virus
ADN
humains
et animaux
géno me
DNA
sb/d
Circulaire
b
sb Circulaire (+/)
db
Circulaire
linéaire
Linéaire (L/S
reg.)
linéaire
taille
(kb)
Enzyme s
structur ales
dans le virion
réplication
3.2
RT, protéine
kinase (PK)
noy au
+
noy au
5-8
36-38
120200
130350
5
DNA pol, PR,
3 PK.
DNA, RNA pol
Soulignements : hépatites; maladies infantiles
enveloppe
assemblage Nom de famille
hepadnaviridae
hépatite B (HBV)
-
intracyt.
vesic
noy au
parvoviridae
5ème maladi e (érythéma)
arthrite rhumatoïde
noy au
-
noy au
papovaviridae
noy au
noy au
+
cytoplasme
+
noy au
adenoviridae
Membrane herpesviridae
nucléaire
cytoplasme poxviridae
papilloma (>50 types)
polyoma JC, SV40
Adéno (48 types)
HSV-1&2, CMV, VZV, EBV,
HHV-6 (roséole), HHV-7,
KSHV (HHV-8)
vacci ne, variole
Classification de virus (David Baltimore)
+ADN
rétrovirus
+ARN
-ADN
+ARN
-ARN
HAV
HCV
HEV
±ADN
HBV
+ARNm
-ARN
±ARN
HCV target cells
Dendritic cell
Hepatocytes

Lymphocytes
B
T
Kupffer
cell
Failure to develop general and efficient permissive system for HCV replication in vitro
Virus de la hépatite C
Virus à l’ARN + : Organisation du génome
Poliomyélite
Hépatite A, C
Fièvre jaune
Resistance to IFN-a
C
polyprotéine
structurales
Protéines non-structurales
ARNm
Core
Envelope
glycoprotein
Serine
protease
domaines protéolytiques
Impairment of
production of IFN-a
Virus de la hépatite A
Virus à l’ARN + : Organisation du génome
HAV, HCV - Virus à ARN + : cycle viral
Hépatocyte
Receptor
inhibitors
Vaccines
Monoclonal antibodies
P7 Inhibitors?
NS3-helicase and
NS5B-Polymerase
inhibitors
Membrane-association
Intervention?
NS2-NS3 and NS3-4A
Protease inhibitors
HCV
E1/E2
CD81
LDLR
Single-stranded RNA
and core (nucleocapsid)
replicase
Ribavirin
IFN-a
HCV therapy
IFN-a, ribavirin  clinical resolution in ≥50% cases
(genotype dependent)
Protease inhibitors (phase 3)
Polymerase inhibitors (phase 3)
Mécanismes de le restriction virale
Virus à l’ARN : interféron
Mechanism of viral detection
TLR (Toll-like receptor)
dsRNA-TLR3
endosome
TLR7-ssRNA
TLR8-ssRNA
TLR9-dsDNA
CARD-helicases
sensors
helicase RIG-1
MDA-5
CARD
TRIF
MyD88
adaptators
MAVS, IPS-1
VISA, CARDIF
mitochondria
nucleus
nucleus
RIG-I, retionic acid induced gene
MDA-5, melanoma differentiating antigen
CARD, caspase activation and recruitment domain
CARDIF, CARD adaptor inducing IFN-b
MAVS, mitochondrial anti-viral signaling
IPS-1, interferon-b promoter stimulator
RIG-1-dependent mechanism of IFN-b induction
in hepatocytes
pDC
Anti-HCV therapy
IFN-a
CD81
LDLR
replication
RIG-1
MDA-5
helicases
NS3/4A
CARD
CARDIF
TBK-1
IKK-e
IRF3
NF-kB
AP-1
nucleus
IFN-b
HCV infection: delicate equilibrium between virus
replication and IFN-a/b interference
Virus de la hépatite B
Hepadna virus : Organisation du génome
middle
Large
small
(+) strand
(-) strand
Polymerase
Core
X
Cycle réplicatif du virus de l’hépatite B (HBV)
Mécanismes de la restriction virale
Virus avec transcriptase inverse : APOBEC3G
Pathogenèse
Pathogenèse de l’infection par
le virus de la hépatite A
Pathogenèse de l’infection par le virus de la hépatite B et C
QuickTime™ et un
décompresseur TIFF (LZW)
sont requis pour visionner cette image.
acute hepatitis
Pathogenèse de l’infection par
le virus de la hépatite B et C
Time line of cumulative morbidity
during chronic infection
HCC
cirrhosis
hepatitis
inactive hepatitis
Chronicité
0% HAV
10% HBV
70% HCV
Virus et cancer
HCV/HBV pathogenesis
Death due to the five most
common cancer diagnoses in 2001
Oncogene (2003), TM Block, R. Jordan
Viral etiology of HCC
Oncogene (2003), TM Block, R. Jordan
Requirements for viral replication
Strict intracellular parasites  proliferating cell
• Permanent activation of cell signal transduction
• Disruption of regulation of:
- cell cycle progression
- cell death, apoptosis
- senescence, telomerase
Immune evasion (Alessandro Moretta)
Virus and Cancer
• ≈ 20% of human cancer
• Malignancy is not required for virus propagation
• Malignancy is a side effect of infection or host response
• Viruses are unwitting initiators of oncogenesis
• Unfortunate outcome for the host
Oncogene transducing retroviruses paradigm
LTR
gag
pol
oncogene
env
LTR
Permanent activation of cell signal transduction
• Protein kinases
src, abl, mos, raf
• Tyrosine kinase growth-factor receptors
erb-B, sea, kit, ros
• Hormone receptors
erbA
• G proteins
H-ras, K-ras
• Nuclear proteins
jun, fos, myc, myb, ets, rel, ski
Seminal role in the cancerogenesis research
Oncogenic viruses and cancer
Viral family
RNA viruses
Flaviviridae
Retroviridae
associated human cancer
HCV
HTLV
HIV
hepatocellular carcinoma  cytoplasma
T cell leukemia
carcinomas, lymphomas
Hepadnaviridae
Papillomaviridae
HBV
HPV16,18
hepatocellular carcinoma 
cervical carcinoma 
Herpesviridae
EBV
KSHV (HHV8)
BL, NPC, XLP, Hodgkin L, post-transplant L
Kaposi’s S, Primary effusion L, Castelman’s
DNA viruses
Virus induced oncogenesis
ONCOPROTEINS
• Variants of cellular genes (HHV8, transducing retroviruses)
• Viral regulatory proteins
not obviously related to cellular genes
short amino acid sequence homology
precise origins not clear
Permanent activation of cell signal transduction pathways
HBV pX
KSHV (HHV8)
V-Gpcr
EBV LMP-1
HBV
NF-kB
HTLV-1
EBV
pX (Ras)
LHB (PKC)
Tax
EBNA-2
LMP-1
Disruption of regulation of cell cycle progression
retinoblastoma
Rb
G2/M restriction
point
G2
p21CIP
M
G1
Cyclins D+Cdk2,4,6
Rb
S
P
P
G1/S restriction point
Proteins of retinoblastoma (Rb) control cell cycle
Functional inactivation of retinoblastoma protein
HPV protein E7
KSHV v-CYC (cdk6)
SV40 LT
Increased synthesis of
cellular and some viral
replication proteins
Cyclins D
Cdk2,4,6
Dp
Dp
Inhibition of synthesis of
cellular and some viral
replication proteins
Disruption of regulation of cell cycle progression
and cell death (apoptosis)
Cell
stress
retinoblastoma
Rb
G2/M restriction
point
G2
p21CIP
• oncogene expression in absence
of growth factors
• Irradiation
apoptose
p53
M
G1
Cyclins D+Cdk2,4,6
Rb
S
P
P
G1/S restriction point
Proteins of retinoblastoma (Rb) and p53 control cell cycle and apoptosis
Inactivation of protein p53 by virale proteins
• Protein level
- ubiquitinylation - proteasome degradation
HPVE6-E6Ap
- sequestration in cytoplasma
HCV NS5A
HBV pX
• Transcription level
- HHV8 LANA2
Inactivation of protein p53 by virale proteins
Protein level
- ubiquitinylation - proteasome degradation
HPVE6-E6Ap
- sequestration in cytoplasma
HCV NS5A
HBV pX
Transcription level
- HHV8 LANA2
Telomere erosion: restriction of proliferative capacity
Cell immortalization
Anti-replicative senescence
Telomerase reverse
transcriptase (TERT)
Oncoproteins of human cancer-related viruses
virus
Signal
transduction
pathway
HCV
core
HTLV-1
tax
HBV
pX
HPV
E6
EBV
KSHV (HHV8)
Cell cycle
Apoptosis
Senescence
(telomerase)
core (TNFR)
NS5A (p53 sequestr)
tax (G1/S)
(inhibit G2/M)
pX
pX
E7 (G1/S)
E6 (p53 ubiquitin)
E6
LMP-1
EBNA-2
EBNA-1
BHRF1
BALF1
LMP1
V-Gpcr
LANA-1
v-Cyc (G1/S)
K-bZIP/RAP
(inhibits G2/M)
LANA-1
LANA-2 (p53 trancr)
V-Bcl2 (Bax)
V-IAP (Casp3)
V-IRF-1(CBP/p300)
LANA-1
Pleiotropic effect
Viral hepatitis and
hepatocellular carcinoma (HCC)
Pathogenesis of virus induced HCC
Leading hypothesis
Indirect effect
• Chronic HBV/HCV infection  virus induced immunological killing 
 Hepatocyte proliferation  mutations  cancerogenesis
• Inflammation and phagocytosis  superoxides and free radicals
Direct effect
Chronic viral infection  virus products  cancerogenesis
Pathogenesis of virus induced HCC
• Oncoproteins are not clearly defined
Lack of adequate models
HBV and HCV replicates in cancer cells
chronicity
Quasispecies
Integration
cirrhosis
oncogene
HBV
10%
-
+
0.2-1%
pX
HCV
60-80%
+
-
5-10%
Core
NS5A
• Are viral gene products necessary for establishment of cancer?
• Does the cancer become independent of virus?
Pathogenesis of virus induced HCC is a complex process
Vaccination against HAV, HBV
No vaccine against HCV
Vaccination against HCC
Which immunogen select?
Are viral proteins potential candidates?