HCV is a major risk factor for hepatocellular carcinoma (HCC). HCC development in chronically infected HCV patients has until now been attributed to persistent inflammation and interference of viral proteins with host cell signaling. Since activation of the epidermal growth factor receptor (EGFR) presents a crucial step in HCV entry, we aimed at investigating whether EGFR signaling may contribute to the pathogenesis of HCV-related HCC.
By applying microarray analysis, we generated a gene expression signature for secreted proteins in HCV-infected hepatoma cells. This gene signature was enriched for inflammatory and angiogenic processes; both crucially involved in HCC development. RT-qPCR analysis, conducted on the entire list of upregulated genes, confirmed induction of 11 genes (AREG, IL8, CCL20, CSF1, GDF15, IGFBP1, VNN3, THBS1 and PAI-1) in a virus titer- and replication-dependent manner. EGFR activation in hepatoma cells largely mimicked the gene signature seen in the infectious HCV model. Further, the EGFR-ERK pathway, but not Akt signaling, was responsible for this gene expression profile. Finally, microarray analysis conducted on clinical data from the GEO database, revealed that our validated gene expression profile is significantly represented in livers of patients with HCV-related liver pathogenesis (cirrhosis and HCC) compared to healthy livers.
Taken together, our data indicate that persistent activation of EGFR-ERK signaling in chronically infected HCV patients may induce a specific pro-inflammatory and pro-angiogenic signature that presents a new mechanism by which HCV can promote liver cancer pathogenesis. A better understanding of the key factors in HCV-related oncogenesis, may efficiently direct HCC drug development.