In contrast to the reported crucial function of EGFR-downstream signaling for the entry of hepatitis C virus (HCV), blockade of EGFR-downstream signaling proteins, including mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and signal transducer and activator of transcription (STAT), had no or only minor effects on HBV infection.
The promotion of invadopodia following HCV infection was mediated by the sustained stimulation of epidermal growth factor receptor (EGFR) via the viral NS3/4A protease that inactivates the T-cell protein tyrosine phosphatase (TC-PTP), which inhibits EGFR signaling.
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.
In the CD81 protein network, we identified five proteins which are HCV entry factors or facilitators including epidermal growth factor receptor (EGFR).
Hepatitis C virus (HCV) enters hepatocytes via various entry factors, including scavenger receptor BI (SR-B1), cluster of differentiation 81 (CD81), epidermal growth factor receptor (EGFR), claudin-1 (CLDN1), and occludin (OCLN).
Interferon lambda 3 (IFNL3) and epidermal growth factor receptor (EGFR) single nucleotide polymorphisms (SNPs) may play a key role in the spontaneous clearance of hepatitis C virus (HCV) and treatment responses.
The finding that chronic hepatitis C virus (HCV) infection might predict poor overall survival (OS) in epidermal growth factor receptor mutation-positive advanced non-small cell lung cancer (NSCLC) patients treated with first-line gefitinib may raise awareness of benefit from anti-HCV treatment in this patient population.
Three out of the 110 SNPs were found to be associated with HCV outcome (P-values<0.03). rs11506105 in EGFR (epidermal growth factor receptor gene), and rs11881222 and rs12979860 in IL28B (interferon-λ3 gene).
Activation of epidermal growth factor receptor (EGFR), a co-factor involved in CD81/CLDN1 interactions, was reduced in IFI6 expressing cells in response to HCV infection or CD81 cross linking by antibody, but not by treatment with EGF.
HCV entry is a complex multistep process involving multiple cell cofactors (glycosaminoglycans, low density lipoprotein receptor, SR-B1, CD81, claudin-1, occludin, EGFR, EphA2) in the interaction with HCV E1/E2 envelope glycoproteins.
Our data suggest that the addition of an EGFR or ERK inhibitor to the current IFN-α-based regimen may improve overall treatment efficacy by blocking the bile acid-mediated promotion of HCV replication.