Increased intrahepatic cyclooxygenase 2, matrix metalloproteinase 2, and matrix metalloproteinase 9 expression is associated with progressive liver disease in chronic hepatitis C virus infection: role of viral core and NS5A proteins.
BACKGROUND
Cyclooxygenase 2 (COX-2) and matrix metalloproteinases (MMPs) have been implicated in tissue injury and fibrogenesis in animal models but little is known regarding their role in hepatitis C virus (HCV) related liver disease in humans.


OBJECTIVE
To characterise the intrahepatic expression pattern of COX-2 and MMPs in chronic HCV infection and determine whether HCV core and NS5A proteins could promote their expression in cultured hepatocyte derived cell lines.


METHODS
Thirty two anti-HCV+ and 10 anti-HCV- patients were studied.


METHODS
Western blot, reverse transcription-polymerase chain reaction (RT-PCR), enzyme immunoassay, and immunohistochemistry were used to assess the expression pattern of COX-2 and MMPs in liver biopsy samples from all patients. COX-2 gene expression and MMP-9 protein levels were also determined by immunoblot, RT-PCR, and luciferase assays in core and NS5A transfected hepatocyte derived cells.


RESULTS
The intrahepatic expression level of COX-2, MMP-2, and MMP-9 was significantly higher in HCV+ than in HCV- patients, increasing with the fibrotic stage of liver disease. We further demonstrated that COX-2 mRNA, protein, and activity were induced in resting and activated core and NS5A transfectants. Both viral proteins induced transcriptional activity of the COX-2 gene promoter whereas core, but not NS5A, exerted an inducer effect on MMP-9 protein levels in cultured hepatocyte derived cells.


CONCLUSIONS
Intrahepatic COX-2, MMP-2, and MMP-9 overexpression is associated with progressive hepatic fibrosis in chronic HCV infection, suggesting their pathogenic role in fibrogenesis. HCV core and NS5A proteins were able to upregulate COX-2 and MMP-9 gene expression in hepatocyte derived cells, providing a potential mechanism for hepatic fibrosis during chronic HCV infection.
Instituto de Hepatología Clínica-Experimental y Trasplante Hepático, Hospital Universitario Gregorio Marañón-Santa Cristina, Madrid, Spain.
O
O
Núñez
A
A
Fernández-Martínez
P L
PL
Majano
A
A
Apolinario
M
M
Gómez-Gonzalo
I
I
Benedicto
M
M
López-Cabrera
L
L
Boscá
G
G
Clemente
C
C
García-Monzón
P
P
Martín-Sanz
D000328:Adult; D002460:Cell Line; D051546:Cyclooxygenase 2; D018450:Disease Progression; D005260:Female; D019698:Hepatitis C, Chronic / Q000201:enzymology* / Q000821:virology; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D020782:Matrix Metalloproteinases / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins; D008875:Middle Aged; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D014162:Transfection; D015854:Up-Regulation; D014758:Viral Core Proteins / Q000235:genetics / Q000502:physiology; D019562:Viral Load; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000502:physiology; D012324:RNA-Dependent RNA Polymerase
D051546:Cyclooxygenase 2; D007527:Isoenzymes; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D020782:Matrix Metalloproteinases; D008565:Membrane Proteins; D011451:Prostaglandin-Endoperoxide Synthases; D012333:RNA, Messenger; D014758:Viral Core Proteins; D017361:Viral Nonstructural Proteins; C069130:nucleocapsid protein, Hepatitis C virus; C496540:PTGS2 protein, human; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase