An intrahepatic gene expression signature of enhanced immune activity predicts response to peginterferon and adefovir in chronic hepatitis B patients

In this study we aimed to identify a baseline intrahepatic transcriptional signature associated with response in chronic hepatitis B patients treated with peginterferon-alfa-2a (peg-IFN) and adefovir. Liver gene expression values of patients with combined response (responders; n=9) and non-response (n=6) were compared for 21,462 annotated gene transcripts. We identified 182 genes which differed on average more than 1.5-fold, of which 53 were relatively upregulated in non-responders and 129 in responders. 15 liver biopsies of chronic hepatitis B patients were selected for RNA extraction and hybridization on Affymetrix microarrays. Expression values in 9 biopsies of patients with a combined response to therapy were compared with 6 biopsies of non-responders. Differentially expressed genes between responders and non-responders were determined using filtering on minimal average expression, fold change (1.5 fold) and p-values from 2-sided t-tests (0 permutations) in GenePattern.