Additional Supporting Information may be found in the online version of this article. “
“Wnt signaling is important for cancer pathogenesis and is often up-regulated in hepatocellular carcinoma (HCC). Heparan sulfate proteoglycans (HSPGs) function as coreceptors or modulators of Wnt activation. Glypican-3 (GPC3) is an HSPG that is highly expressed in HCC, where it can attract Wnt proteins to the cell surface and promote cell proliferation. Thus, GPC3 has emerged as a candidate therapeutic target in liver cancer. While monoclonal antibodies to GPC3 are currently being evaluated in preclinical and clinical studies, none have shown an
effect on Wnt signaling. Here, we first document the expression of Wnt3a, multiple Wnt receptors, and GPC3 in several Talazoparib price HCC cell lines, and demonstrate that GPC3 enhanced the activity of Wnt3a/β-catenin signaling in these cells. Then we report the identification
of HS20, a human monoclonal antibody against GPC3, which preferentially recognized the heparan sulfate chains of GPC3, both the sulfated and nonsulfated portions. HS20 disrupted the interaction of Wnt3a and GPC3 and blocked Wnt3a/β-catenin signaling. Moreover, HS20 inhibited Wnt3a-dependent cell proliferation in vitro and HCC xenograft growth in nude mice. In addition, HS20 had no detectable undesired toxicity MK-1775 mouse in mice. Taken together, our results show that a monoclonal antibody primarily targeting the heparin sulfate chains of GPC3 inhibited Wnt/β-catenin signaling in HCC cells and had potent antitumor activity in vivo. Conclusion:
An antibody directed against the heparan sulfate of a proteoglycan shows efficacy in blocking Wnt signaling and HCC growth, find more suggesting a novel strategy for liver cancer therapy. (Hepatology 2014;60:576–587) “
“Hepatitis E virus (HEV) infection is usually self-limited but may lead to acute hepatitis and rarely to fulminant hepatic failure. Persistent HEV infections have recently been described in organ transplant recipients receiving immunosuppressive medications, suggesting that HEV is controlled by adaptive immune responses. However, only few studies have investigated HEV-specific T-cell responses and immune correlates for the failure to clear HEV infection have not been established so far. We investigated T-cell responses against HEV in 38 subjects including anti-HEV-positive (exposed, n = 9) and anti-HEV-negative (n = 10) healthy controls, 12 anti-HEV-positive but HEV RNA-negative organ transplant recipients, and seven transplant recipients with chronic hepatitis E. Proliferation as well as cytokine production of CD4+ and CD8+ T cells was studied after stimulation with overlapping peptides spanning all proteins encoded by HEV-open reading frame (ORF)2 and HEV-ORF3.