ヒトテロメラーゼ逆転写酵素(hTERT)の多量体形成やテロメラーゼ活性に重要な役割を果たすhTERTの独立した二領域の検討

取得学位 : 博士（医学）, 学位授与番号 : 医博甲第1517号 , 学位授与年月日 : 平成14年3月22日, 学位授与大学 : 金沢大

Peretinoin, an acyclic retinoid, improves the hepatic gene signature of chronic hepatitis C following curative therapy of hepatocellular carcinoma

BACKGROUND: The acyclic retinoid, peretinoin, has been shown to be effective for suppressing hepatocellular carcinoma (HCC) recurrence after definitive treatment in a small-scale randomized clinical trial. However, little has been documented about the mechanism by which peretinoin exerts its inhibitory effects against recurrent HCC in humans in vivo. METHODS: Twelve hepatitis C virus-positive patients whose HCC had been eradicated through curative resection or ablation underwent liver biopsy at baseline and week 8 of treatment with either a daily dose of 300 or 600 mg peretinoin. RNA isolated from biopsy samples was subjected to gene expression profile analysis. RESULTS: Peretinoin treatment elevated the expression levels of IGFBP6, RBP1, PRB4, CEBPA, G0S2, TGM2, GPRC5A, CYP26B1, and many other retinoid target genes. Elevated expression was also observed for interferon-, Wnt-, and tumor suppressor-related genes. By contrast, decreased expression levels were found for mTOR- and tumor progression-related genes. Interestingly, gene expression profiles for week 8 of peretinoin treatment could be classified into two groups of recurrence and non-recurrence with a prediction accuracy rate of 79.6% (P<0.05). In the liver of patients with non-recurrence, expression of PDGFC and other angiogenesis genes, cancer stem cell marker genes, and genes related to tumor progression was down-regulated, while expression of genes related to hepatocyte differentiation, tumor suppression genes, and other genes related to apoptosis induction was up-regulated. CONCLUSIONS: Gene expression profiling at week 8 of peretinoin treatment could successfully predict HCC recurrence within 2 years. This study is the first to show the effect of peretinoin in suppressing HCC recurrence in vivo based on gene expression profiles and provides a molecular basis for understanding the efficacy of peretinoin

Expression of chondroitin-glucuronate C5-epimerase and cellular immune responses in patients with hepatocellular carcinoma

Background & Aims: Chondroitin-glucuronate C5-epimerase is an enzyme that converts D-glucuronic acid to L-iduronic acid residues in dermatan sulphate biosynthesis. It is also identified to be a tumour-associated antigen recognized by cytotoxic T cells (CTLs) and its enhanced expression in many cancers has been reported. In the present study, we investigated the usefulness of this molecule as an immunotherapeutic target in hepatocellular carcinoma (HCC). Methods: The expression of chondroitin-glucuronate C5-epimerase in hepatoma cell lines and HCC tissues was confirmed by immunofluorescence and immunohistochemical analysis. CTL responses were investigated by several immunological techniques using peripheral blood mononuclear cells (PBMCs) or tumour-infiltrating lymphocytes. To determine the safety of immunotherapy using chondroitin-glucuronate C5-epimerase-derived peptide, 12 patients with HCC were administered s.c. vaccinations of the peptides and analysed. Results: Chondroitin-glucuronate C5-epimerase was expressed in HCC cell lines and human tissues including alpha-foetoprotein (AFP)-negative individuals. Chondroitin-glucuronate C5-epimerase-specific CTLs could be generated by stimulating PBMCs of HCC patients with peptides and they showed cytotoxicity against HCC cells expressing the protein. The frequency of CTL precursors investigated by enzyme-linked immunospot (ELISPOT) assay was 0-34 cells/3 × 10 5 PBMCs and the infiltration of interferon-gamma-producing CTLs into the tumour site was confirmed. In the vaccination study, no severe adverse events were observed and the peptide-specific CTLs were induced in 4 of 12 patients tested. Conclusions: Chondroitin-glucuronate C5-epimerase is a potential candidate for tumour antigen with immunogenicity and the peptides derived from this antigen could be useful in HCC immunotherapy. © 2012 John Wiley & Sons A/S

Myeloid-derived suppressor cells correlate with patient outcomes in hepatic arterial infusion chemotherapy for hepatocellular carcinoma

Hepatic arterial infusion chemotherapy (HAIC) has been employed as an alternative therapy to sorafenib for the patients with advanced hepatocellular carcinoma (HCC). In this study, we performed a comparative analysis of various immune cell responses including tumor-associated antigen (TAA)-specific T cells, regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) in advanced HCC patients treated with HAIC. Thirty-six HCC patients were examined in the study. Interferon gamma enzyme-linked immunospot assays were performed to examine the frequency of TAA-specific T cells. The frequencies of Tregs and MDSCs were examined by multicolor fluorescence-activated cell sorting analysis. The treatment with HAIC using interferon (IFN)/5-fluorouracil (FU) or IFN/FU + cisplatin modulated the frequencies of various immune cells. In 22.2 % of patients, the frequency of TAA-specific T cells increased after HAIC. Although the frequency of Tregs decreased after HAIC, it was not associated with the prognosis of patients. An analysis of prognostic factors for overall survival identified diameter of the tumor (<3.0 cm), absence of major portal vein invasion, absence of distant metastasis, Union Internationale Contre Le Cancer tumor lymph node metastasis stage (I or II), neutrophil lymphocytic ratio (<2.1) and the frequency of MDSCs (<30.5 %) as factors that prolonged overall survival time after HAIC. Even in the group adjusted with progressive levels of tumors, patients with a low frequency of MDSCs had a significantly longer overall survival time. In conclusion, the frequency of MDSCs before the treatment is a prognostic factor in HAIC against HCC. © 2016 Springer-Verlag Berlin Heidelber

Phase I trial of multidrug resistance-associated protein 3-derived peptide in patients with hepatocellular carcinoma

Multidrug resistance-associated protein 3 (MRP3) is a carrier-type transport protein belonging to the ABC transporters. In this study, we investigated the safety and immunogenicity of a MRP3-derived peptide (MRP3765) as a vaccine and characterized the MRP3-specific T cell responses induced. Twelve hepatocellular carcinoma (HCC) patients treated with hepatic arterial infusion chemotherapy (HAIC) were enrolled. The MRP3-derived peptide was emulsified in incomplete Freund\u27s adjuvant and administered via subcutaneous immunization three times weekly. No serious adverse drug reactions to the peptide vaccine were observed, and the vaccination was well tolerated. The vaccination induced MRP3-specific immunity in 72.7% of the patients. In a phenotypic analysis, the largest post-vaccinated increase in MRP3-specific T cells was due to an increase in cells with the effector memory phenotype. Among the 12 patients, one patient showed a partial response, nine showed a stable disease, and two showed a progressive disease. The median overall survival time was 14.0 months. In conclusion, the safety, effects of immune boosting, and possible prolongation of overall survival by the MRP3-derived peptide demonstrate the potential of the peptide to provide clinical benefit in HCC patients. © 2015

Identification of a secretory protein c19orf10 activated in hepatocellular carcinoma

The identification of genes involved in tumor growth is crucial for the development of inventive anticancer treatments. Here, we have cloned a 17-kDa secretory protein encoded by c19orf10 from hepatocellular carcinoma (HCC) serial analysis of gene expression libraries. Gene expression analysis indicated that c19orf10 was overexpressed in approximately two-thirds of HCC tissues compared to the adjacent noncancerous liver tissues, and its expression was significantly positively correlated with that of alpha-fetoprotein (AFP). Overexpression of c19orf10 enhanced cell proliferation of AFP-negative HLE cells, whereas knockdown of c19orf10 inhibited cell proliferation of AFP-positive Hep3B and HuH7 cells along with G1 cell cycle arrest. Supplementation of recombinant c19orf10 protein in culture media enhanced cell proliferation in HLE cells, and this effect was abolished by the addition of antibodies developed against c19orf10. Intriguingly, c19orf10 could regulate cell proliferation through the activation of Akt/mitogen-activated protein kinase pathways. Taken together, these data suggest that c19orf10 might be one of the growth factors and potential molecular targets activated in HCC. Copyright © 2010 UICC

Enhancement of tumor-associated antigen-specific T cell responses by radiofrequency ablation of hepatocellular carcinoma

Radiofrequency ablation (RFA) is one of the treatments for hepatocellular carcinoma (HCC) and is known to enhance host immune response. However, the epitopes to which enhanced immune responses occur, the impact on patient prognosis, and the functions and phenotype of T cells induced are still unclear. To address these issues, we analyzed immune responses before and after RFA in 69 HCC patients using 11 tumor-associated antigen (TAA)-derived peptides that we identified to be appropriate to analyze HCC-specific immune responses. The immune responses were analyzed using enzyme-linked immunospot (ELISPOT) assay and tetramer assays using peripheral blood mononuclear cells. An increase in the number of TAA-specific T cells detected by interferon-γ ELISPOT assays occurred in 62.3% of patients after RFA. The antigens and their epitope to which enhanced T cell responses occur were diverse, and some of them were newly induced. The number of TAA-specific T cells after RFA was associated with the prevention of HCC recurrence, and it was clarified to be predictive of HCC recurrence after RFA by univariate and multivariate analyses. The number of TAA-specific T cells after RFA was inversely correlated with the frequency of CD14+HLA-DR-/low myeloid-derived suppressor cells (MDSCs). The modification of T cell phenotype was observed after RFA. The number of TAA-specific T cells at 24 weeks after RFA was decreased. Conclusion: Although RFA can enhance various TAA-specific T cell responses and the T cells induced contribute to the HCC recurrence-free survival of patients, besides immunosuppression by MDSCs, the memory phenotype and lifetime of TAA-specific T cells are not sufficient to prevent HCC recurrence completely. Additional treatments by vaccine or immunomodulatory drugs might be useful to improve the immunological effect of RFA. © 2012 American Association for the Study of Liver Diseases

Response to chemotherapy improves hepatic reserve for patients with hepatocellular carcinoma and Child–Pugh B cirrhosis

There is no established treatment for patients with advanced hepatocellular carcinoma (HCC) with Child–Pugh class B cirrhosis. The aim of the present study was to assess the efficacy of hepatic arterial infusion chemotherapy (HAIC) according to Child–Pugh score (CPS) and to evaluate the correlation of a patient\u27s response to HAIC with hepatic reserve and outcome. We retrospectively reviewed the medical records of 377 patients treated with HAIC between March 2003 and February 2015. Subjects included 179 with Child–Pugh class B. Median overall survival was 12.1 months for patients with CPS = 7 (n = 75) and 11.9 months for patients with CPS = 8 (n = 58), which were significantly longer compared with those of patients with CPS = 9 (n = 46, 6.3 months). The objective response rates of patients with CPS = 7, 8 and 9 were 26.7%, 27.6% and 6.5%, respectively. The CPS of responders improved significantly after HAIC, whereas those of nonresponders did not. A multivariate analysis demonstrated that improved CPS, responses to HAIC and absence of extrahepatic lesions were independent favorable prognostic factors. Patients with CPS = 7 or 8 tolerated HAIC, but nine (19.6%) of patients with CPS = 9 were unable to complete one course. HAIC is effective and safe for patients with a CPS = 7 or 8 and improved hepatic reserve of responders significantly. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association