Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously reported several CTL epitopes derived from the hepatitis B viral X Ag (HBx). In this study, we evaluated whether HBx-specific CTLs can be effectively used in adoptive cancer immunotherapy. To validate the possibility, four peptides containing a HLA-A2.1-restricted binding consensus motif were identified from the HBx protein and tested for their ability to activate CTL from PBMCs isolated from chronic carriers of HBV (n = 12). We selected two highly potent epitopes, HBx 52-60 (HLSLRGLFV) and HBx 115-123 (CLFKDWEEL), that are capable of inducing Ag-specific cytotoxic T cells in patient PBMCs. For adoptive immunotherapy using HBx-specific CTLs, we generated CTL clones restricted to the HBx 52-60 or HBx 115-123 peptide using a limiting dilution technique. LC-46, an HBx 52-60-specific clone, is CD62L(-)CD69(+)CD45RO(+)CD45RA(-)CD25(dim) and is stained by IFN-gamma (approximately 92%), IL-2 (30%), and TNF-alpha (56%), but not by IL-5, IL-10, IL-12, or TNF-beta, indicating that the cells are fully activated T cytotoxic 1-type cells. When LC-46 cells were adoptively transferred into xenografted nude mice bearing human hepatomas expressing HLA-A2.1 molecules and intracellular HBx proteins, the tumors were eradicated. Taken together, our data provide solid evidence for the feasibility of adoptive immunotherapy with HBx-sensitized CTLs in hepatitis disease, including hepatocellular carcinoma (HCC).
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PMID:Tumor eradication by hepatitis B virus X antigen-specific CD8+ T cells in xenografted nude mice. 1253 74

Thrombocytopenia is an important complication of interferon (IFN) therapy for chronic viral hepatitis. To study whether IFN interferes with hepatic thrombopoietin (TPO) synthesis, we used the human hepatoma cell line HepG2. Our results show that IFN-alpha, IFN-beta, or IFN-gamma did not impair TPO mRNA expression, as determined by quantitative RT-PCR, even when high IFN doses (up to 5000 U/ml) or long-term incubations (up to 14 days) were applied. Neither was the rate of secretion of immunoreactive TPO reduced on IFN treatment. These findings support the concept that IFNs primarily mediate effects on megakaryocytic cells and platelets rather than on TPO-producing hepatocytes.
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PMID:Thrombopoietin production in human hepatic cell cultures (HepG2) is resistant to IFN-alpha, IFN-beta, and IFN-gamma treatment. 1258 91

A female patient, who was suffering major depression and advanced hepatocellular carcinoma (hepatoma), sought treatment in the Jozuka Mental Clinic. She was treated using a psycho-neuro-immunological approach. The treatments applied were psychotherapy, the antidepressant fluvoxamine, glycyrrhizinic acid and dehydroepiandrosterone (DHEA). Biochemical, endocrinological and immunological examinations were performed regularly. Improvement of liver function and reduction of alpha-fetoprotein were observed. The levels of DHEA, natural killer cell activity and cytokines (interleukines IL-2, IL-6, IL-12, interferon IFN-gamma) were normalised. Now, more than two and a half years after her admission, the patient is still well and symptom-free. While this may be a case of spontaneous regression, the results suggest that a psycho-neuro-immunological approach to treating the patient's depression and cancer was helpful for her recovery.
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PMID:Psycho-neuro-immunological treatment of hepatocellular carcinoma with major depression--a single case report. 1266 82

Chronic hepatitis B virus (HBV) infection can cause a broad spectrum diseases, including from asymptomatic HBV carriers or cryptic hepatitis, to acute hepatitis, chronic hepatitis, Liver cirrhosis and primary hepatocellular carcinoma. The variable pattern and clinical outcome of the infection were mainly determined by virological itself factors, host immunological factors and genetic factors as well as the experimental factors. Among the human genetic factors, major candidate or identified genes involved in the process of HBV infection fall into the following categories: (1) genes that mediate the processes of viral entry into hepatocytes, including genes involved in viral binding, fusion with cellular membrane and transportation in target cells; (2) genes that modulate or control the immune response to HBV infection; (3) genes that participate in the pathological alterations in liver tissue; (4) genes involved in the development of liver cirrhosis and hepatocellular carcinoma associated with chronic HBV infection, including genes related to mother-to-infant transmission of HBV infection; and (5) those that contribute to resistance to antiviral therapies. Most of the reports of human genes associated with HBV infection have currently focused on HLA associations. For example, some investigators reported the association of the HLA class II alleles such as DRB1*1302 or HLA-DR13 or DQA1*0501-DQB1*0301-DQB1*1102 haplotypes with acute and/or chronic hepatitis B virus infection, respectively. Several pro-inflammatory cytokines such as Th1 cytokines (including IL-2 and IFN-gamma) and TNF-alpha have been identified to participate the process of viral clearance and host immune response to HBV. In contrast, the Th2 cytokine IL-10 serves as a potent inhibitor of Th1 effector cells in HBV diseases. The MBP polymorphisms in its encoding region were found to be involved in chronic infection. Thus, reports from various laboratories have shown some inconsistencies with regard to the effects of host genetic factors on HBV clearance and persistence. Since genetic interactions are complex, it is unlikely that a single allelic variant is responsible for HBV resistance or susceptibility. However, the collective influence of several single nucleotide polymorphisms (SNPs) or haplotype (s) may underlie the natural combinational or synergistic protection against HBV. The future study including the multi-cohort collaboration will be needed to clarify these preliminary associations and identify other potential candidate genes. The ongoing study of the distributions and functions of the implicated allele polymorphisms will not only provide insight into the pathogenesis of HBV infection, but may also provide a novel rationale for new methods of diagnosis and therapeutic strategies.
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PMID:Current status and prospects of studies on human genetic alleles associated with hepatitis B virus infection. 1267 1

Transforming growth factor-beta1 (TGF-beta1) exerts potent immunosuppressive effects. In this study, we investigated the potential role of TGF-beta1 produced by hepatocellular carcinoma (HCC) cell lines in immunosuppression mechanisms. Using the Mv1Lu cell-growth inhibition assay and an enzyme-linked immunosorbent assay (ELISA), we detected optimal levels of TGF-beta1 in the culture supernatants conditioned by the HCC cell lines PLC/PRF/5, Hep3B, and HepG2. To determine the biological activity of TGF-beta1 in the supernatants, we examined the effects of the culture supernatants on the production of interferon (IFN)-gamma induced during the culture of peripheral blood mononuclear cells (PBMCs) stimulated with interleukin (IL)-12. IFN-gamma production of IL-12-stimulated PBMCs in the 1:1 dilution of the acid-activated conditioned medium of PLC/PRF/5, Hep3B, and HepG2 reduced to 14.7 +/- 0.8, 17.3 +/- 9.0, and 35.9 +/- 14.6%, respectively, compared with the value in the culture with control medium (complete culture medium). These results suggest that HCC cells producing TGF-beta1 may reduce the generation or activation of cytotoxic T lymphocytes (CTL) and natural killer (NK) cells, and thus could enhance their ability to escape immune-mediated surveillance.
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PMID:Suppressive effects of transforming growth factor-beta1 produced by hepatocellular carcinoma cell lines on interferon-gamma production by peripheral blood mononuclear cells. 1268 60

Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands have been reported to exert anti-inflammatory activities in macrophages by competition for transcriptional coactivators with some transcriptional factors, including NF-kappaB. In the present study the influence of PPARgamma activators on IFN-gamma-elicited macrophage stimulation and signaling cascades was investigated. The results show that IFN-gamma-induced inducible NO synthase (iNOS) gene transcription, iNOS protein induction, and NO production are more sensitive to inhibition by 15-deoxy-Delta(12,14)-prostaglandin J(2) (15dPGJ(2)) than by the other two PPARgamma agonists, GW1929 and ciglitazone. Delayed addition of 15dPGJ(2) for 2 h resulted in reduced inhibition, suggesting action by 15dPGJ(2) on the upstream signaling cascades. Immunoblotting, DNA binding, and reporter gene assays consistently revealed the inhibitory ability of 15dPGJ(2), but not GW1929 or ciglitazone, on IFN-gamma-elicited signaling cascades, including tyrosine phosphorylation of Janus tyrosine protein kinase 2 and STAT1, DNA binding, and IFN regulatory factor-1 trans-activation of STAT1. These effects of 15dPGJ(2) were not abrogated by the PPARgamma antagonist, bisphenol A diglycidyl ether, indicating the PPARgamma-independent actions. 15dPGJ(2) also attenuated IL-6-induced tyrosine phosphorylation of STAT1 and STAT3 in Hep3B hepatoma cells. Consistent with the inhibitory effect of reactive oxygen species on STAT1 signaling, STAT1 inhibition by 15dPGJ(2) was abrogated by N-acetylcysteine, glutathione, superoxide dismutase, and catalase. Furthermore, 15dPGJ(2)-induced inhibition of STAT1 phosphorylation and NO production still occurred in the presence of peroxovanadate, ruling out the action mechanism of 15dPGJ(2) on tyrosine phosphatase. Taken together, for the first time in this study we demonstrate that 15dPGJ(2) can inhibit cytokine-stimulated Janus kinase 2-STAT signaling through a PPARgamma-independent, reactive oxygen species-dependent mechanism. These data provide a novel molecular mechanism of iNOS inhibition by 15dPGJ(2) and confirm its physiological role in anti-inflammation.
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PMID:Inhibition of IFN-gamma-mediated inducible nitric oxide synthase induction by the peroxisome proliferator-activated receptor gamma agonist, 15-deoxy-delta 12,14-prostaglandin J2, involves inhibition of the upstream Janus kinase/STAT1 signaling pathway. 1284 70

X gene product of hepatitis B virus (HBV) (HBx) regulates many transcription factors including nuclear factor kappa B (NF-kappaB) and plays a key role in hepatocarcinogenesis. In this study, we demonstrated that the expression of full HBV genome and HBx gene similarly stimulated the transcriptional activity of NF-kappaB in HuH-7 human hepatoma cells, and that interferon (IFN)-alpha as well as dominant negative mutant of IkappaB kinase-alpha effectively inhibited the HBx-mediated NF-kappaB activation, but IFN-gamma did not. These results suggest that IFN-alpha may have a function to block the NF-kappaB activating pathway triggered by HBx in HBV hepatocytes.
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PMID:Interferon alpha inhibits the nuclear factor kappa B activation triggered by X gene product of hepatitis B virus in human hepatoma cells. 1457 41

IFN-gamma (interferon-gamma) modulates IFN-alpha therapy in chronic hepatitis C infection; however, the underlying mechanism remains unclear. Here we demonstrate that long-term (3-6 days) but not short-term (up to 1 day) IFN-gamma treatment of human hepatoma Hep3B cells attenuates IFN-alpha activation of STAT1 (signal transducers and activators of transcription factor 1), STAT2 and STAT3, but enhances IFN-gamma and interleukin 6 activation of STATs. Prolonged exposure to IFN-gamma also significantly induces STAT1 protein expression without affecting STAT2, STAT3 and ERK (extracellular-signal-regulated kinase) 1/2 protein expression. To determine the role of STAT1 protein overexpression in regulation of IFN-alpha signalling, Hep3B cells were stably transfected with wild-type STAT1. Overexpression of STAT1 via stable transfection enhances IFN-gamma activation of STAT1, but surprisingly attenuates IFN-alpha activation of STAT1, STAT2 and STAT3 without affecting Janus kinase activation. This STAT1-mediated inhibition does not require STAT1 tyrosine phosphorylation because overexpression of dominant-negative STAT1 with a mutation on tyrosine residue 701 also blocks IFN-alpha activation of STAT1, STAT2 and STAT3. Moreover, overexpression of STAT1 blocks IFN-alpha-activated STAT2 translocation from IFN-alpha receptor 2 to IFN-alpha receptor 1, a critical step in IFN-alpha signalling activation. Finally, significantly higher levels of STAT1 protein expression, which is probably induced by IFN-gamma, are detected in the majority of hepatitis C virus-infected livers compared with healthy controls. In conclusion, long-term IFN-gamma treatment inhibits IFN-alpha-activated signals most probably, at least in part, through the induction of STAT1 protein expression, which could partly contribute to IFN-alpha treatment failure in hepatitis C patients.
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PMID:Interferon-gamma inhibits interferon-alpha signalling in hepatic cells: evidence for the involvement of STAT1 induction and hyperexpression of STAT1 in chronic hepatitis C. 1469 Apr 54

In patients with hepatocellular carcinoma (HCC), natural killer (NK) cell activity decreases significantly, and the reduced activity may be associated with the progression of HCC. In this study we evaluated the effects of pulsing with interleukin (IL)-2 and/or IL-12 on the activation of freshly isolated peripheral blood lymphocytes (PBL) derived from patients with HCC. PBL obtained from 9 HCC patients, 4 liver cirrhosis patients, and 9 normal subjects were cultured in the presence of IL-2 and/or IL-12. After 24 h of incubation, the levels of interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha presented in the supernatants were determined by enzyme-linked immunosorbent assay (ELISA). The IFN-gamma and TNF-alpha production of PBL pulsed by a combination of IL-2 and IL-12 was significantly higher than those of PBL stimulated by either IL-2 or IL-12 alone. The mRNA encoding perforin, granzyme B, as well as IFN-gamma and TNF-alpha, were markedly enhanced in PBL stimulated with a combination of IL-12 and IL-2. The pulsing procedure of IL-12 in combination with IL-2 resulted in the increase of IFN-gamma and TNF-alpha, and the expression of perforin and granzyme B mRNA in PBL obtained from HCC patients, as well as in those obtained from normal subjects. These results indicate that adoptive immunotherapy based on PBL pulsed with a combination of IL-2 and IL-12 may be a promising adjunctive strategy for HCC treatment.
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PMID:Effects of pulsing procedure of interleukin-12 in combination with interleukin-2 on the activation of peripheral blood lymphocytes derived from patients with hepatocellular carcinoma. 1472 65

Expression of the granzyme B inhibitors, human proteinase inhibitor 9 (PI-9), or the murine orthologue, serine proteinase inhibitor 6 (SPI-6), confers resistance to CTL or NK killing by perforin- and granzyme-dependent effector mechanisms. In light of prior studies indicating that virally infected hepatocytes are selectively resistant to this CTL effector mechanism, the present studies investigated PI-9 and SPI-6 expression in hepatocytes and hepatoma cells in response to adenoviral infection and to cytokines produced during antiviral immune responses. Neither PI-9 nor SPI-6 expression was detected by immunoblotting in uninfected murine or human hepatocytes. Similarly, human Huh-7 hepatoma cells were found to express only very low levels of PI-9 relative to levels detected in perforin- and granzyme-resistant CTL or lymphokine-activated killer cells. Following in vivo adenoviral infection or in vitro culture with IFN-alphabeta or IFN-gamma, SPI-6 expression was induced in murine hepatocytes. Similarly, after culture with IFN-alpha, induction of PI-9 mRNA and protein expression was observed in human hepatocytes and Huh-7 cells. IFN-gamma and TNF-alpha also induced 4- to 10-fold higher levels of PI-9 mRNA expression in Huh-7 cells, whereas levels of mRNA encoding a related serine proteinase inhibitor, proteinase inhibitor 8, were unaffected by culture of Huh-7 cells with IFN-alpha, IFN-gamma, or TNF-alpha. These findings indicate that cytokines that promote antiviral cytopathic responses also regulate expression of the cytoprotective molecules, PI-9 and SPI-6, in hepatocytes that are potential targets of CTL and NK effector mechanisms.
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PMID:Antiviral cytokines induce hepatic expression of the granzyme B inhibitors, proteinase inhibitor 9 and serine proteinase inhibitor 6. 1512 37


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