Ken Yamaguchi

Japan Research Institute, Sizuoka, Shizuoka, Japan

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Publications (120)352.93 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Local recurrence is a major clinical issue following surgical resection in head and neck cancer. However, the dissemination and lymph node metastasis of minimal residual disease is relatively difficult to treat due to the lack of suitable therapeutic approaches. In the present study, we developed and evaluated a novel immunotherapy using a skin flap transfer treated with sensitized dendritic cells (DCs), termed the "immuno-flap" in a rat tumor model. After the local round area of skin was resected, SCC-158 cells (a rat head and neck cancer cell line) were inoculated into the muscle surface; lastly, the groin skin flap injected with mature DCs was over-laid. Two weeks after the second DC injection, systemic immunological reactions and tumor size were measured. The DC-treated group showed a significant reduction in tumor size compared with the control. Although the induction of CTL activity in spleen cells was marginal, Th1 cytokines such as IL-2 and IFN-γ were elevated in the DC-treated group. These results suggest that novel immunotherapy based on the immuno-flap method has the potential for clinical application to prevent the local recurrence of head and neck cancer patients. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Cancer Science 12/2014; 106(2). DOI:10.1111/cas.12586 · 3.48 Impact Factor
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    ABSTRACT: Exosomes are small vesicles secreted from cells that transport their embedded molecules through bidirectional exocytosis- and endocytosis-like pathways. Expression patterns of exosomal molecules such as proteins and RNAs can be indicative of cell type since their signature is thought to be unique among cells. Using human primary (AZ-521) and metastatic (AZ-P7a) duodenal cancer cell lines, we conducted a comparative exosomal proteome analysis to identify proteins with metastatic marker potential. As determined by LC-MS/MS and western blot analyses, polyadenylate binding protein 1 (PABP1) was found to be predominantly abundant in AZ-P7a exosomes. The amount of exosomal PABP1 in AZ-P7a cells increased by treating the cells with inhibitors for the classical endoplasmic reticulum/Golgi secretory pathway (brefeldin A and monensin) and the ubiquitin-proteasome pathway (MG-132 and PYR-41). Treatment of AZ-P7a cells with the neutral sphingomyelinase inhibitor GW4869, which suppresses exosome release, not only reduced the amount of exosomal PABP1 but also produced PABP1-immunoreactive products cleaved via a proteolysis-like process. Taken together, these results suggest that AZ-P7a cells do not tolerate to intracellular PABP1 accumulation and is thus exported into the extracellular milieu by the exosome-mediated pathway. In addition, PABP1 has a potential use as a biomarker for metastatic duodenal cancer.This article is protected by copyright. All rights reserved
    Proteomics 10/2014; 14(20). DOI:10.1002/pmic.201300477 · 3.97 Impact Factor
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    ABSTRACT: XIAP-associated factor 1 (XAF1) is ubiquitously expressed in normal tissues, but its suppression in cancer cells is strongly associated with tumor progression. Although downregulation of XAF1 is observed in tumors, its expression profile in the peripheral blood of cancer patients has not yet been investigated. Here, we identified a novel XAF1 splice variant in cancer cells and then investigated the expression level of this variant in peripheral blood containing gastric cancer-derived circulating tumor cells (CTCs).
    Gastric Cancer 09/2014; DOI:10.1007/s10120-014-0426-3 · 4.83 Impact Factor
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    ABSTRACT: During the past decade, cancer stem-like cells (CSCs) have drawn substantial interest in cancer research since they have been described as major targets to improve treatment of tumors and to prevent recurrence and metastasis. In this paper, we report on the search for CSCs within the Colo205 human adenocarcinoma cell line. We describe that CD133 (prominin) was the only reliable marker for the isolation and characterization of CSCs within a Colo205 cell population. CD133-positive cells displayed many CSC characteristics, such as tumorsphere formation ability, expression of early-stage development markers, high invasiveness, raised tumor initiation potential and resistance to cisplatin chemotherapy treatment. In vitro analyses also highlighted a specific metabolomic profile of CD133-positive cells and we concluded that the chemotherapy resistance of CSCs could be related to the quiescence of such cells associated with their reduced metabolism. Furthermore, in vivo metabolome analyses suggested that a high level of circulating glutathione molecules could also promote treatment resistance. From the perspective of metabolomics, we also discuss the controversial use of serum-free in vitro cultures for CSC enrichment prior to further phenotype characterization.
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    ABSTRACT: Background/Aim: The acquisition of resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) remains a major challenge in lung cancer medicine. We sought to identify biomarkers for the early detection of resistance to TKIs. Materials and Methods: Capillary electrophoresis time-of-flight mass spectrometry analysis was performed to identify the metabolic signatures associated with erlotinib resistance in erlotinib-resistant PC-9ER NSCLC cells established from the EGFR-mutant NSCLC cell line PC-9. Results: PC-9ER cells showed metabolic signatures indicative of enhanced glutamine metabolism. Copy number gains in v-myc avian myelocytomatosis viral oncogene homolog (MYC), glutathione-S-transferase theta 2 (GSTT2), gamma-glutamyltransferase 1 (GGT1), and GGT5 were also detected, suggesting that amplification of these genes confers glutamine addiction in PC-9ER cells. Conclusion: Enhanced glutamine metabolism may be a surrogate marker that can be used to predict the likelihood of patients to respond to EGFR-TKIs.
    Anticancer research 06/2014; 34(6):2779-2787. · 1.87 Impact Factor
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    ABSTRACT: The frequent recurrence of glioblastoma multiforme (GBM) after standard treatment with temozolomide (TMZ) is a crucial issue to be solved in the clinical field. O6‑methylguanine‑DNA methyltransferase (MGMT) is considered one of the major mechanisms involved in TMZ resistance. However, some important mechanisms for TMZ resistance other than MGMT have recently been identified. In the present study, we established a TMZ-resistant (TMZ-R) U87 glioblastoma cell line in vitro and in vivo and investigated novel targeting molecules other than MGMT in those cells. The TMZ-R U87 glioblastoma cell line was established in vitro and in vivo. TMZ-R U87 cells showed a more invasive activity and a shorter survival time in vivo. Gene expression analysis using DNA microarray and quantitative PCR (qPCR) demonstrated that YKL‑40, MAGEC1 and MGMT mRNA expression was upregulated 100-, 83- and 6-fold, respectively in the TMZ-R U87 cell line. Western blot analysis and qPCR demonstrated that STAT3 phosphorylation, STAT3 target genes and stem cell and mesenchymal marker genes were upregulated to a greater extent in the TMZ‑resistant cell line. Notably, short hairpin (sh)RNA‑based inhibition against the YKL‑40 gene resulted in moderate growth inhibition in the resistant cells in vitro and in vivo. Additionally, YKL‑40 gene inhibition exhibited significant suppression of the invasive activity and particularly partially restored the sensitivity to TMZ. Therefore, YKL‑40 may be a novel key molecule in addition to MGMT, that is responsible for TMZ resistance in glioblastoma cell lines and could be a new target to overcome TMZ resistance in recurrent glioblastomas in the future.
    Oncology Reports 05/2014; 32(1). DOI:10.3892/or.2014.3195 · 2.19 Impact Factor
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    ABSTRACT: Glioblastoma multiforme (GBM) is one of the most malignant and aggressive tumors and has a very poor prognosis, with a median survival time of less than 2 years. Once recurrence develops, there are few therapeutic approaches to control the growth of glioblastoma. In particular, temozolomide (TMZ)-resistant (TMZ-R) GBM is very difficult to treat, and a novel approach to overcome resistance is eagerly awaited. Previously, we reported a novel small molecule inhibitor of STAT3 dimerization, STX-0119, as a cancer therapeutic. In the current study, the efficacy of STX-0119 was evaluated against our established TMZ-resistant U87 cell line using quantitative PCR-based gene expression analysis, in vitro assay and animal experiments. The growth inhibitory effect of STX-0119 on U87 and TMZ-R U87 cells was moderate (IC50, 34 and 45 µM, respectively). In particular, STX-0119 did not show significant inhibition of U87 tumor growth; however, it suppressed the growth of the TMZ-R U87 tumor in nude mice by more than 50%, and prolonged the median survival time compared to the control group. Quantitative PCR revealed that YKL-40, MAGEC1, MGMT, several EMT genes, mesenchymal genes and STAT3 target genes were upregulated, but most of those genes were downregulated by STX-0119 treatment. Furthermore, the invasive activity of TMZ-R U87 cells was significantly inhibited by STX-0119. YKL-40 levels in TMZ-R U87 cells and their supernatants were significantly decreased by STX-0119 administration. These results suggest that STX-0119 is an efficient therapeutic to overcome TMZ resistance in recurrent GBM tumors, and could be the next promising compound leading to survival prolongation, and YKL-40 may be a possible surrogate marker for STAT3 targeting.
    International Journal of Oncology 05/2014; 45(1). DOI:10.3892/ijo.2014.2439 · 3.03 Impact Factor
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    ABSTRACT: Antibody direct cloning from single B cells is simple and efficient and has been successful in antibody identification of infectious diseases. However, although a recent whole-exome sequencing revealed abundant heterogeneic mutation accumulation in cancers, identification and synthesis of autoantibodies against specific cancer-associated antigens is still difficult in cancer patients owing to the very small number of B cells producing autoantibodies. In the present study, to identify autoantibodies targeting tumor antigens, we measured the titer of autoantibodies in high-grade glioma patients’ plasma and identified two patients with elevated autoantibodies to a few transmembrane proteins. Specific B cells producing autoantibody against vascular endothelial growth factor receptor (VEGFR) 2 were immunostained with labeled protein and anti-human IgG antibody, and then collected by a single cell sorter. Finally, 22 antibody genes were successfully identified using direct IgG cloning from single B cell mRNA, and two antibody clones were found to have significant VEGFR2-specific binding affinity. The current direct human IgG gene cloning technique for identifying human antibodies derived from IgG-memory B cells avoids time-consuming procedures such as phage display-based antibody-library screening, and therefore may be applicable to identifying human autoantibodies in a variety of disorders including cancers even when antibody elevation is not detected because of a very small number of memory B cells.
    Immunology letters 05/2014; 159(1-2). DOI:10.1016/j.imlet.2014.02.004 · 2.37 Impact Factor
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    ABSTRACT: Glioblastoma multiforme (GBM) is one of the most malignant and aggressive tumors, and has a very poor prognosis with a mean survival time of <2 years, despite intensive treatment using chemo-radiation. Therefore, novel therapeutic approaches including immunotherapy have been developed against GBM. For the purpose of identifying novel target antigens contributing to GBM treatment, we developed 17 primary glioma cell lines derived from high-grade glioma patients, and analyzed the expression of various tumor antigens and glioma-associated markers using a quantitative PCR and immunohistochemistry (IHC). A quantitative PCR using 54 cancer-testis (CT) antigen-specific primers showed that 36 CT antigens were positive in at least 1 of 17 serum-derived cell lines, and 17 antigens were positive in >50% cell lines. Impressively, 6 genes (BAGE, MAGE-A12, CASC5, CTAGE1, DDX43 and IL-13RA2) were detected in all cell lines. The expression of other 13 glioma-associated antigens than CT genes were also investigated, and 10 genes were detected in >70% cell lines. The expression of CT antigen and glioma-associated antigen genes with a high frequency were also verified in IHC analysis. Moreover, a relationship of antigen gene expressions with a high frequency to overall survival was investigated using the Repository of Molecular Brain Neoplasia Data (REMBRANDT) database of the National Cancer Institute, and expression of 6 genes including IL-13RA2 was inversely correlated to overall survival time. Furthermore, 4 genes including DDX43, TDRD1, HER2 and gp100 were identified as MGMT-relevant factors. In the present study, several CT antigen including novel genes were detected in high-grade glioma primary cell lines, which might contribute to developing novel immunotherapy and glioma-specific biomarkers in future.
    Oncology Reports 02/2014; 31(4). DOI:10.3892/or.2014.3049 · 2.19 Impact Factor
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    ABSTRACT: Calcium phosphate (CaP) ceramics including hydroxyapatite (HA) and beta-tricalcium phosphate (β-TCP) have been widely used for bone substitution in orthopedic, maxillofacial and dental surgery, as well as in tumor resections. CaP particles are also known to cause inflammatory responses, which are thought to be an unfavorable characteristic of prosthetic coating materials. On the other hand, the immunostimulatory effect of β-TCP induces an anti-tumor effect in xenograft tumor models in athymic mice. To date, in depth analysis of the biological effects of β-TCP has not been studied in mice. In the present study, in vivo biological effects of β-TCP were investigated by subcutaneously injecting β-TCP particles into mice. This induced extensive migration of immune cells to the area surrounding the injection. In addition, we found that in vitro treatment with β-TCP in murine monocyte/macrophage cells (J774A.1) induced up-regulation of surface expression of CD86, and increased production of TNF-α, MIP-1α, and sICAM-1. Furthermore, conditioned medium from J774A.1 cells treated with β-TCP facilitated migration of murine splenocytes in a transwell migration assay. These findings clarify that β-TCP induces an immunostimulatory effect in mice, and suggest a potential for β-TCP as a novel adjuvant for cancer therapy.
    International immunopharmacology 01/2014; DOI:10.1016/j.intimp.2013.12.024 · 2.71 Impact Factor
  • Biomedical research (Tokyo, Japan) 01/2014; 35(6):407-12. DOI:10.2220/biomedres.35.407 · 1.10 Impact Factor
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    ABSTRACT: Of all potential biological therapeutics, monoclonal antibody (mAb)-based therapies are becomingthe dominant focus of clinical research. In particular, smaller recombinant antibody fragments suchas single-chain variable fragments (scFv) have become the subject of intense focus. However, anefficient affinity ligand for antibody fragment purification has not been developed. In the presentstudy, we designed a consensus sequence for the human antibody heavy or light chain-variable regions(Fv) based on the antibody sequences available in the ImMunoGeneTics information system(IMGT), and synthesized these consensus sequences as template Fv antibodies. We then screenedpeptide ligands that specifically bind to the repertoire-derived human Fv consensus antibody usinga 12-mer-peptide library expressed-phage display method. Subsequently, 1 peptide for the VHtemplate and 8 peptides for the VK template were selected as the candidate ligands after 4 roundsof panning the phage display. Using peptide-bead-based immunoprecipitation, the code-4 andcode-13 peptides showed recovery rates of the VH and VK templates that were 20-30% and 40-50%, respectively. Both peptides exhibited better recovery rates for trastuzumab scFv (approximately40%). If it were possible to identify the best combination of VH and VK-binding peptidesamong the ligand peptides suitable for the human mAb Fv sequence, the result could be a promisingpurification tool that might greatly improve the cost efficiencies of the purification process.
    Biomedical Research 01/2014; 35(2):105-16. DOI:10.2220/biomedres.35.105 · 1.10 Impact Factor
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    ABSTRACT: Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) is an oncofetal cell surface glycoprotein. Because of its high expression in cancer cells and secretion into serum, CEA has been widely used as a serum tumor marker. Although other members of CEACAM family were investigated for splice variants/variants-derived protein isoforms, few studies about the variants of CEACAM5 have been reported. In this study, we demonstrated the existence of novel CEACAM5 splice variants and splice variant-derived protein isoforms in gastrointestinal cancer cell lines. We identified two novel CEACAM5 splice variants in gastrointestinal (pancreatic, gastric, and colorectal) cancer cell lines. One of the variants possessed an alternative minor splice site that allowed generation of GC-AG intron. Furthermore, CEA protein isoforms derived from the novel splice variants were expressed in cancer cell lines and those protein isoforms were secreted into the culture medium. Although CEA protein isoforms always co-existed with the full-length protein, the secretion patterns of these isoforms did not correlate with the expression patterns. This is the first study to identify the expression of CEA isoforms derived from the novel splice variants processed on the unique splice site. In addition, we also revealed the secretion of those isoforms from gastrointestinal cancer cell lines. Our findings suggested that discrimination between the full-length and identified protein isoforms may improve the clinical utility of CEA as a tumor marker.
    BMC Research Notes 09/2013; 6(1):381. DOI:10.1186/1756-0500-6-381
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    ABSTRACT: Epithelial cell adhesion molecule (EpCAM)-based enumeration of circulating tumor cells (CTC) has prognostic value in patients with solid tumors, such as advanced breast, colon, and prostate cancer. However, poor sensitivity has been reported for non-small cell lung cancer (NSCLC). To address this problem, we developed a microcavity array (MCA) system integrated with a miniaturized device for CTC isolation without relying on EpCAM expression. Here, we report the results of a clinical study on CTCs of advanced lung cancer patients in which we compared the MCA system with the CellSearch system, which employs the conventional EpCAM-based method. Paired peripheral blood samples were collected from 43 metastatic lung cancer patients to enumerate CTCs using the CellSearch system according to the manufacturer's protocol and the MCA system by immunolabeling and cytomorphological analysis. The presence of CTCs was assessed blindly and independently by both systems. CTCs were detected in 17 of 22 NSCLC patients using the MCA system versus 7 of 22 patients using the CellSearch system. On the other hand, CTCs were detected in 20 of 21 small cell lung cancer (SCLC) patients using the MCA system versus 12 of 21 patients using the CellSearch system. Significantly more CTCs in NSCLC patients were detected by the MCA system (median 13, range 0-291 cells/7.5 mL) than by the CellSearch system (median 0, range 0-37 cells/7.5 ml) demonstrating statistical superiority (p = 0.0015). Statistical significance was not reached in SCLC though the trend favoring the MCA system over the CellSearch system was observed (p = 0.2888). The MCA system also isolated CTC clusters from patients who had been identified as CTC negative using the CellSearch system. The MCA system has a potential to isolate significantly more CTCs and CTC clusters in advanced lung cancer patients compared to the CellSearch system.
    PLoS ONE 06/2013; 8(6):e67466. DOI:10.1371/journal.pone.0067466 · 3.53 Impact Factor
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    ABSTRACT: In this study, we present a method for efficient enrichment of small-sized circulating tumor cells (CTCs) such as those found in the blood of small cell lung cancer (SCLC) patients using a microcavity array (MCA) system. To enrich CTCs from whole blood, a microfabricated nickel filter with a rectangular MCA (104 cavities/filter) was integrated with a miniaturized device, allowing for the isolation of tumor cells based on differences in size and deformability between tumor and blood cells. The shape and porosity of the MCA were optimized to efficiently capture small tumor cells on the microcavities under low flow resistance conditions, while allowing other blood cells to effectively pass through. Under optimized conditions, approximately 80% of SCLC (NCI-H69 and NCI-H82) cells spiked in 1 mL of whole blood, were successfully recovered. In clinical samples, CTCs were detectable in 16 of 16 SCLC patients. In addition, the number of leukocytes captured on the rectangular MCA was significantly lower than that on the circular MCA (p < 0.001), suggesting that use of the rectangular MCA diminishes a considerable number of carryover leukocytes. Therefore, our system has potential as a tool for the detection of CTCs in small cell-type tumors and detailed molecular analyses of CTCs.
    Analytical Chemistry 05/2013; 85(12). DOI:10.1021/ac400167x · 5.83 Impact Factor
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    ABSTRACT: Signal transducer and activator of transcription (STAT) 3, a member of a family of DNA-binding molecules, is a potential target in the treatment of cancer. The highly phosphorylated STAT3 in cancer cells contributes to numerous physiological and oncogenic signaling pathways. Furthermore, a significant association between STAT3 signaling and glioblastoma multiforme stem-like cell (GBM-SC) development and maintenance has been demonstrated in recent studies. Previously, we reported a novel small molecule inhibitor of STAT3 dimerization, STX-0119, as a cancer therapeutic. In the present study, we focused on cancer stem-like cells derived from recurrent GBM patients and investigated the efficacy of STX-0119. Three GBM stem cell lines showed many stem cell markers such as CD133, EGFR, Nanog, Olig2, nestin and Yamanaka factors (c-myc, KLF4, Oct3/4 and SOX2) compared with parental cell lines. These cell lines also formed tumors in vivo and had similar histological to surgically resected tumors. STAT3 phosphorylation was activated more in the GBM-SC lines than serum-derived GB cell lines. The growth inhibitory effect of STX-0119 on GBM-SCs was moderate (IC50 15-44 µM) and stronger compared to that of WP1066 in two cell lines. On the other hand, the effect of temozolomide was weak in all the cell lines (IC50 53-226 µM). Notably, STX-0119 demonstrated strong inhibition of the expression of STAT3 target genes (c-myc, survivin, cyclin D1, HIF-1α and VEGF) and stem cell-associated genes (CD44, Nanog, nestin and CD133) as well as the induction of apoptosis in one stem-like cell line. Interestingly, VEGFR2 mRNA was also remarkably inhibited by STX-0119. In a model using transplantable stem-like cell lines in vivo GB-SCC010 and 026, STX-0119 inhibited the growth of GBM-SCs at 80 mg/kg. STX-0119, an inhibitor of STAT3, may serve as a novel therapeutic compound against GBM-SCs even in temozolomide-resistant GBM patients and has the potential for GBM-SC-specific therapeutics in combination with temozolomide plus radiation therapy.
    International Journal of Oncology 04/2013; 43(1). DOI:10.3892/ijo.2013.1916 · 3.03 Impact Factor
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    ABSTRACT: 2-deoxy-D-glucose (2DG) has been clinically evaluated for its potential use as an anticancer drug. Although 2DG is generally thought to inhibit the glycolytic pathway through accumulation of 2-deoxy-D-glucose-6-phosphate (2DG6P), it may also interfere with various other biological processes. Here, to further understand the role of 2DG as an inhibitor of tumor progression, we assessed the metabolism of 2DG in a human endometrial cancer cell line using capillary electrophoresis-time-of-flight mass spectrometry (CE-TOFMS). A total of 113 target metabolite peaks were identified and 90 metabolites of them were quantified. Furthermore, we present a new methodology which uses CE-TOFMS metabolome profiling following introduction of an artificial metabolite to evaluate tumor-specific metabolite traces. Aside from 2DG6P, we detected the presence of unique 2DG-derived deoxy metabolites in 2DG-treated cells. These metabolites may be responsible for the alteration of global metabolism in cells and act as various biological effectors.
    Biomedical Research 01/2013; 34(5):221-9. DOI:10.2220/biomedres.34.221 · 1.10 Impact Factor
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    ABSTRACT: BACKGROUND: High-grade gliomas including glioblastoma multiforme (GBM) are among the most malignant and aggressive of tumors, and have a very poor prognosis despite a temozolomide-based intensive treatment. Therefore, a novel therapeutic approach to controlling recurrence is needed. In the present study, we investigated the effect of activated dendritic cell (DC) (alpha-type-1 polarized DC)-based immunotherapy on high-grade glioma patients with the HLA-A2 or A24 genotype. METHODS: Nine patients with recurrent high-grade gliomas including 7 with GBMs who fulfilled eligibility criteria were enrolled into a phase I study of monocyte-derived DC-based immunotherapy. HLA-genotyping revealed 1 case of HLA-A*0201 and 8 cases of A*2402. Enriched monocytes obtained using OptiPrepTM from leukapheresis products on day1, were incubated with GM-CSF and IL-4 in a closed serum-free system, and activated on day6 with TNF-alpha, IL-1beta, IFN-alpha, IFN-gamma, and poly I/C. After pulsing with a cocktail of 5 synthetic peptides (WT-1, HER2, MAGE-A3, and MAGE-A1 or gp100) restricted to HLA-A2 or A24 and KLH, cells were cryopreserved until used. Thawed DCs were injected intradermally in the posterior neck at a dose per cohort of 1.0, 2.0 and 5.0x 107/body. RESULTS: The frequency of CD14+ monocytes increased to 44.6% from 11.9% after gradient centrifugation. After a 7-day-incubation with cytokines, the mean percentage of DCs rated as lin-HLA-DR+ in patients was 56.2 +/- 19.1 %. Most DCs expressed high levels of maturation markers, co-stimulatory molecules and type-1 phenotype (CD11c+HLA-DR+) with a DC1/2 ratio of 35.6. The amount of IL-12 produced from activated DCs was 1025 +/- 443 pg/ml per 105 cells. All 76 DC injections were well tolerated except for transient liver dysfunction with grade II. Six patients showed positive immunological responses to peptides in an ELISPOT assay, and positive skin tests to peptide-pulsed DC and KLH were recognized in 4 cases. The clinical response to DC injections was as follows :1 SD and 8 PD. Interestingly, the SD patient, given 24 DC injections, showed a long-term recurrence-free and immunological positive response period. CONCLUSIONS: These results indicate peptide cocktail-treated activated alpha-type-1 DC-based immunotherapy to be a potential therapeutic tool against recurrent high-grade glioma with mainly HLA-A*2402.Trial registration: Current non-randomized investigational trial UMIN-CTR UMIN ID: 000000914.
    BMC Cancer 12/2012; 12(1):623. DOI:10.1186/1471-2407-12-623 · 3.32 Impact Factor
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    ABSTRACT: Background Alternative splicing of pre-mRNA transcripts not only plays a role in normal molecular processes but is also associated with cancer development. While normal transcripts are ubiquitously expressed in normal tissues, splice variants created through abnormal alternative splicing events are often expressed in cancer cells. Although the Rho GDP dissociation inhibitor β (ARHGDIB) gene has been found to be ubiquitously expressed in normal tissues and involved in cancer development, the presence of splice variants of ARHGDIB has not yet been investigated. Results Validation analysis for the presence of and exon structures of splice variants of ARHGDIB, performed using reverse-transcriptase polymerase chain reaction and DNA sequencing, successfully identified novel splice variants of ARHGDIB, that is, 6a, 6b, and 6c, in colon, pancreas, stomach, and breast cancer cell lines. Quantitative real-time polymerase chain reaction analysis showed that these variants were also highly expressed in normal placental tissue but not in other types of normal tissue. Conclusions Expression of ARHGDIB variants 6a, 6b, and 6c appears to be restricted to cancer cells and normal placental tissue, suggesting that these variants possess cancer-specific functions and, as such, are potential cancer-related biomarkers.
    BMC Research Notes 12/2012; 5(1):666. DOI:10.1186/1756-0500-5-666
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    ABSTRACT: Metastatic and chemoresistant melanoma can be a good target of immunotherapy because it is an intractable cancer with a very poor prognosis. Previously, we tested a dendritic cell (DC)-based phase I vaccine, and confirmed that it was safe. In the present study, we performed a phase II trial of a DC vaccine for metastatic melanoma patients with mainly the HLA-A24 genotype, and investigated the efficacy of the vaccine. Twenty-four patients with metastatic melanoma were enrolled into a phase II study of DC-based immunotherapy. The group included 19 HLA-A24-positive (A*2402) patients and 3 HLA-A2-positive (A*0201) patients. The protocol for DC production was similar to that in the phase I trial. Briefly, a cocktail of 5 melanoma-associated synthetic peptides (gp100, tyrosinase, MAGE-A2, MAGE-A3 and MART-1 or MAGE‑A1) restricted to HLA-A2 or A24 and KLH were used for DC pulsing. Finally, DCs were injected subcutaneously (s.c.) into the inguinal region in the dose range of 1-5x107 per shot. The DC ratio (lin-HLA-DR+) of the vaccine was 38.1±13.3% and the frequency of CD83+ DCs was 25.7±20.8%. Other parameters regarding DC processing were not different from phase I. Immune response-related parameters including the ELISPOT assay, DTH reaction to peptide or KLH, DC injection numbers were shown to be related to a good prognosis. The ELISPOT reaction was positive in 75% of the patients vaccinated. The increase of anti-melanoma antigen antibody titer before vaccination was also shown to be a prognosis factor, but that post-vaccination was not. Based on immunohistochemical analysis, CD8 and IL-17 were not involved in the prognosis. Adverse effects of more than grade III were not seen. Overall survival analysis revealed a significant survival prolongation effect in DC-given melanoma patients. These results suggest that peptide cocktail-treated DC vaccines may be a safe and effective therapy against metastatic melanoma in terms of prolongation of overall survival time.
    Oncology Reports 08/2012; 28(4):1131-8. DOI:10.3892/or.2012.1956 · 2.19 Impact Factor

Publication Stats

2k Citations
352.93 Total Impact Points

Institutions

  • 2014
    • Japan Research Institute
      Sizuoka, Shizuoka, Japan
  • 2003–2014
    • Shizuoka Cancer Center
      • • Division of Immunotherapy
      • • Division of Cancer Survivorship Research
      Sizuoka, Shizuoka, Japan
  • 1982–2002
    • National Cancer Center, Japan
      Edo, Tōkyō, Japan
  • 1989
    • Showa University
      Shinagawa, Tōkyō, Japan