Expression data of HCV-associated advance disease state

Introduction: Mechanisms that contribute to the pathogenesis of liver damage caused by hepatitis C virus (HCV) are not fully understood. Our previous work on liver biopsies from chronic HCV patients has shown modulation of the expression of certain cell cycle proteins indicating HCV-induced modifications of cell cycle events. We therefore hypothesize that HCV infection disrupts normal regulation of cell cycle that contributes to disease progression. Objective: To identify molecular disruptions during the course of HCV-associated disease progression, using liver biopsy specimens of chronic hepatitis C patients. Methods: Liver biopsy samples classified on histological basis as early (fibrosis stage 0-1) or advanced (fibrosis stage 3-4) disease stage were studied using oligonucleotide array ( HG U133 Plus 2.0, Affymetrix GeneChip™ System). For comparison, liver specimens from patients with non-viral hepatitis were also analyzed by microarray. Expression data was analyzed using Genespring (GX 7.2) and Ingenuity Pathway analysis (3.0). The differential expression of selected cell cycle genes (cyclin D2, KPNA2, HERC5 and Bcl-2) identified after microarray analysis was confirmed by quantitative real-time RT-PCR. Results: Microarray analysis revealed two-fold or greater transcriptional change in 792 genes of the total 38,500 known human genes in HCV-advance disease stage (HCV-A) as compared to HCV-early disease stage (HCV-E). Most of the genes have a defined role in immune response, extracellular matrix and cell cycle and apoptosis. Keywords: HCV-advance disease state Liver biopsy samples were collected from patients of (a) HCV-infected early disease stage (HCV-E, control 1) (b) non-HCV advance disease stage (control 2) and (c) HCV-infected advance disease stage (HCV-A) for RNA extraction. Equal amount of RNA was pooled from samples (n=4)within each group and hybridized to HG-U133 Plus 2.0 array.