Hepatic microRNA expression is associated with the response to interferon treatment of chronic hepatitis C.
BACKGROUND
HCV infection frequently induces chronic liver diseases. The current standard treatment for chronic hepatitis (CH) C combines pegylated interferon (IFN) and ribavirin, and is less than ideal due to undesirable effects. MicroRNAs (miRNAs) are endogenous small non-coding RNAs that control gene expression by degrading or suppressing the translation of target mRNAs. In this study we administered the standard combination treatment to CHC patients. We then examined their miRNA expression profiles in order to identify the miRNAs that were associated with each patient's drug response.


METHODS
99 CHC patients with no anti-viral therapy history were enrolled. The expression level of 470 mature miRNAs found their biopsy specimen, obtained prior to the combination therapy, were quantified using microarray analysis. The miRNA expression pattern was classified based on the final virological response to the combination therapy. Monte Carlo Cross Validation (MCCV) was used to validate the outcome of the prediction based on the miRNA expression profile.


RESULTS
We found that the expression level of 9 miRNAs were significantly different in the sustained virological response (SVR) and non-responder (NR) groups. MCCV revealed an accuracy, sensitivity, and specificity of 70.5%, 76.5% and 63.3% in SVR and non-SVR and 70.0%, 67.5%, and 73.7% in relapse (R) and NR, respectively.


CONCLUSIONS
The hepatic miRNA expression pattern that exists in CHC patients before combination therapy is associated with their therapeutic outcome. This information can be utilized as a novel biomarker to predict drug response and can also be applied to developing novel anti-viral therapy for CHC patients.
Murakami
Yoshiki
Y
Center for Genomic Medicine, Kyoto University Graduate School of Medicine, 53 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan. ymurakami@genome.med.kyoto-u.ac.jp
Tanaka
Masami
M
Toyoda
Hidenori
H
Hayashi
Katsuyuki
K
Kuroda
Masahiko
M
Tajima
Atsushi
A
Shimotohno
Kunitada
K
D004338:Drug Combinations; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D057809:HEK293 Cells; D019698:Hepatitis C, Chronic / Q000188:drug therapy* / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007372:Interferons / Q000494:pharmacology / Q000627:therapeutic use*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D009010:Monte Carlo Method; D016133:Polymerase Chain Reaction; D015203:Reproducibility of Results; D013997:Time Factors; D016896:Treatment Outcome
D004338:Drug Combinations; D035683:MicroRNAs; D007372:Interferons