Inhibition of hepatitis C virus infection in cell culture by small interfering RNAs.

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease and hepatocellular carcinoma, yet fully efficacious treatments are missing. In this study, we investigated RNA interference (RNAi), a specific gene silencing process mediated by small interfering RNA (siRNA) duplexes, as an antiviral strategy against HCV. Synthetic siRNAs were designed to target conserved sequences of the HCV 5' nontranslated region (NTR) located in a functional, stem-loop structured domain of the HCV internal ribosome entry site (IRES), which is crucial for initiation of polyprotein translation.