PubMed Health⌕ Search

Biomedical subjects

Yoshiaki Miura

Publications and source records attributed to Yoshiaki Miura.

11 recordsLinked to original sources
PubMed2007

One-pot solid-phase glycoblotting and probing by transoximization for high-throughput glycomics and glycoproteomics.

The development of rapid and efficient methods for high-throughput protein glycomics is of growing importance because the glycoform-focused reverse proteomics/genomics strategy will greatly contribute to the discovery of novel biomarkers closely related to cellular development, differentiation, growth, and aging as well as a variety of diseases such as cancers and viral infection. Recently, we communicated that rapid and efficient purification of carbohydrates can be achieved by employing sugar-specific chemical ligation with aminooxy-functionalized polymers, which we termed "glycoblotting" (see S.-I. Nishimura et al., Angew. Chem. 2005, 117, 93-98; Angew. Chem. Int. Ed. 2005, 44, 91-96). The chemoselective blotting of oligosaccharides present in crude biological materials onto synthetic polymers relies on the unique oxime-bond formation between aminooxy group displayed on the supporting materials and aldehyde/ketone group at the reducing terminal of all oligosaccharides, thus enabling highly selective and rapid oligosaccharide purification. Aiming to improve the detection sensitivity of the released oligosaccharides, we introduce here a novel strategy for one-pot solid-phase glycoblotting and probing by transoximization. We found that oligosaccharides captured by the polymer supports via the oxime bond can be released in the presence of excess O-substituted aminooxy derivatives in a weakly acidic condition. The released oligosaccharides could be recovered as newly formed oxime derivatives of the O-substituted aminooxy compound added, thus demonstrating the simultaneous releasing and probing. In addition, we synthesized a novel aminooxy-functionalized monomer, N-[2-[2-(2-tert-butoxycarbonylaminooxyacetylamino-ethoxy)ethoxy]ethyl]-2-methacrylamide, which allows for the large-scale preparation of a versatile polymer characterized by its high stability, high blotting capacity, and easy use. The one-pot protocol allowed to profile 23 kinds of N-glycan chains of human serum glycoproteins. This concept was further applied for the glycopeptides analysis in a crude mixture followed by galactose oxidase treatment to generate free aldehyde group at the non-reducing terminal of oligosaccharide moiety of glycopeptides. Our technique may be implemented in existing biochemistry and molecular diagnostics laboratories because enriched oligosaccharides and glycopeptides by solid-phase transoximization with high-sensitive labeling reagents are widely applicable in a variety of common analytical methods using two-dimensional HPLC, LC/MS, and capillary electrophoresis as well as modern mass spectrometry.

Acrylamides↗
PubMed2006

Allogeneic MHC gene transfer enhances antitumor activity of allogeneic hematopoietic stem cell transplantation without exacerbating graft-versus-host disease.

Enhancement of the specific antitumor activity of allogeneic hematopoietic stem cell transplantation (alloHSCT) against solid cancers is a major issue in the clinical oncology. In this study, we examined whether intratumoral allogeneic MHC (alloMHC) gene transfer can enhance the recognition of tumor-associated antigens by donor T cells and augment the antitumor activity of alloHSCT. In minor histocompatibility antigen-mismatched alloHSCT (DBA/2-->BALB/c: H-2(d)) recipients, alloMHC gene (H-2K(b)) was transduced directly into a s.c. tumor of CT26 colon cancer cells. Because CT26 cells have an aggressive tumorigenicity in syngeneic BALB/c mice, an H-2K(b) gene transfer provides only a limited antitumor effect after syngeneic (BALB/c-->BALB/c) HSCT. By contrast, the H-2K(b) gene transfer caused significant tumor suppression in the alloHSCT recipients, and this suppression was evident not only in the gene-transduced tumors but also in simultaneously inoculated distant tumors without gene transduction. In vitro cytotoxicity assay showed specific tumor cell lysis by donor T cells responding to the H-2K(b) gene transfer. Graft-versus-host disease was not exacerbated serologically or clinically in the treated mice, demonstrating that alloMHC gene transfer enhances the antitumor effects of alloHSCT without exacerbating graft-versus-host disease. This combination strategy has important implications for the development of therapies for human solid cancers.

Animals↗
PubMed2006

Cryptogenic liver disease in four children: a novel congenital disorder of glycosylation.

We investigated the metabolic defect(s) of four children who presented with isolated cryptogenic chronic liver disease, coagulopathy, and abnormalities of several unrelated serum glycoproteins. Analysis of the patients' serum glycoproteins and fibroblasts suggest they have a novel congenital disorder of glycosylation (CDG). All had abnormal transferrin (Tf) isoelectric focusing (IEF) profiles. More detailed analysis of Tf by electrospray ionization mass spectrometry (ESI-MS) showed a plethora of abnormal glycosylations that included loss of 1-2 sialic acids and 1-2 galactose units, typical of Group II defects. Tf from two patients also lacked 1-2 entire oligosaccharide chains, typical of Group One disorders. Total serum N-glycans were analyzed by HPLC and matrix-assisted laser desorption/ionization mass spectrometry and also showed increased proportion of neutral glycan chains lacking sialic acids and galactose units. Analysis of patient fibroblasts eliminated CDG-Ia, through CDG-Ih, -IL and CDG-IId. Our results suggest that a subset of children with clinically asymptomatic, cryptogenic hypertransaminasemia and/or liver steato-fibrosis may represent a novel type of CDG-X with an unknown defect(s). Clinicians are encouraged to test such patients for abnormal Tf glycosylation by ESI-MS.

Child, Preschool↗
PubMed2005

Intraperitoneal injection of adenovirus expressing antisense K-ras RNA suppresses peritoneal dissemination of hamster syngeneic pancreatic cancer without systemic toxicity.

We examined the antitumor effect and safety of the adenovirus-mediated expression of antisense K-ras RNA in two peritoneal dissemination models of pancreatic cancer. First, we found that the infection of an adenovirus vector expressing antisense human K-ras RNA (AxCA-AS) induced significant apoptosis in vitro in human pancreatic cancer cells with K-ras mutation. Second, the intraperitoneal (ip) injection of AxCA-AS effectively suppressed the growth of human pancreatic cancer cells in the peritoneal cavity of nude mice. Third, in the hamster syngeneic peritoneal dissemination model, the ip injection of an adenovirus expressing antisense hamster K-ras RNA significantly suppressed the peritoneal growth of hamster pancreatic cancer cells, and no significant systemic toxicity was observed in the treated hamsters. This study suggests a feasibility of the development of a therapeutic strategy against pancreatic cancer based on the adenovirus-mediated transduction of an antisense K-ras construct.

Adenoviridae↗
PubMed2004

Interferon-alpha and antisense K-ras RNA combination gene therapy against pancreatic cancer.

Interferon alpha (IFN-alpha) is used worldwide for the treatment of a variety of cancers. For pancreatic cancer, recent clinical trials using IFN-alpha in combination with standard chemotherapeutic drugs showed some antitumor activity of the cytokine, but the effect was not significant enough to enlist pancreatic cancer as a clinically effective target of IFN-alpha. In general, an improved therapeutic effect and safety are expected for cytokine therapy when given in a gene therapy context, because the technology would allow increased local concentrations of this cytokine in the target sites. In this study, we first examined the antiproliferative effect of IFN-alpha gene transduction into pancreatic cancer cells. The expression of IFN-alpha effectively induced growth suppression and cell death in pancreatic cancer cells, an effect which appeared to be more prominent when compared with other types of cancers and normal cells. Another strategy we have been developing for pancreatic cancer targets its characteristic genetic aberration, K-ras point mutation, and we reported that the expression of antisense K-ras RNA significantly suppressed the growth of pancreatic cancer cells. When these two gene therapy strategies are combined, the expression of antisense K-ras RNA significantly enhanced IFN-alpha-induced cell death (1.3- to 3.5-fold), and suppressed subcutaneous growth of pancreatic cancer cells in mice. Because the 2',5'-oligoadenylate synthetase/RNase L pathway, which is regulated by IFN and induces apoptosis of cells, is activated by double-strand RNA, it is plausible that the double-strand RNA formed by antisense and endogenous K-ras RNA enhanced the antitumor activity of IFN-alpha. This study suggested that the combination of IFN-alpha and antisense K-ras RNA is a promising gene therapy strategy against pancreatic cancer.

Adenoviridae↗
PubMed2004

Plasma and urine levels of urinary trypsin inhibitor in patients with chronic liver diseases and hepatocellular carcinoma.

BACKGROUND AND AIM: Because urinary trypsin inhibitor (UTI) is synthesized by hepatocytes and excreted into the urine, plasma and urine levels of UTI may alter in liver diseases. However, there are few reports on the changes in these levels in chronic liver diseases and hepatocellular carcinoma (HCC). The aim of the present study was to evaluate the relationships between plasma and urine UTI levels and the severity of liver damage or progression of HCC in patients with chronic liver diseases and HCC. METHODS: Plasma and urine UTI levels were measured by a newly developed enzyme-linked immunosorbent assay in 16 patients with chronic hepatitis (CH), 19 patients with liver cirrhosis (LC) and 39 patients with HCC. RESULTS: Plasma UTI level exhibited a significant positive correlation with the urine UTI level. Plasma and urine UTI levels significantly decreased in LC patients compared with those of normal controls. In contrast, the plasma UTI level in HCC patients was higher than that in LC patients, but there was no difference between the groups in the urine UTI level. Plasma and urine UTI levels in LC and HCC patients were significantly correlated with the degree of liver damage according to the Child-Pugh classification. Although neither the plasma nor urine level of UTI in HCC patients were related to the clinical stage of HCC, both levels were closely associated with the level of protein induced by vitamin K absence or antagonist-II. CONCLUSIONS: The present findings indicate that the levels of plasma and urine UTI in patients with LC reflect the severity of liver damage. In HCC patients, these levels may also reflect progression of HCC, although further study is required.

Adult↗
PubMed2003

Development of a prostate-specific promoter for gene therapy against androgen-independent prostate cancer.

Androgen ablation has been the standard treatment for metastasized prostate cancer. In most cases, however, prostate cancer cells eventually lose androgen dependency and become refractory to the conventional endocrine therapy. Androgen-independent prostate cancer is characterized by a heterogeneous loss of androgen receptor (AR) expression among tumor cells. Prostate-specific promoters such as prostate-specific antigen and rat probasin (rPB) promoters have been examined in the development of gene therapy targeted to prostate cancer. However, those promoters require binding of the androgen-AR complex to the androgen-response element and are active only in the androgen-dependent prostate cancer cell lines and not in the androgen-independent cell lines. To target transgene expression in androgen-independent prostate cancer, we designed a prostate-specific promoter that is activated by the retinoids-retinoid receptor complex instead of the androgen-AR complex. The modified rPB promoters expressed transgenes in response to retinoid in both androgen-dependent and androgen-independent prostate cancer cells and not in other cancer cell lines or in human normal cells, in vitro and in vivo. Furthermore, the combination of retinoid treatment and adenovirus-mediated gene transfer of the modified rPB-driven HSV-tk gene resulted in a significant growth suppression of the androgen-independent prostate cancer cells in the presence of the prodrug ganciclovir. This study suggests that tailoring of the hormone-responsive elements may offer a new therapeutic opportunity against the hormone-refractory stage of prostate cancer.

Adenoviridae↗
PubMed2003

A simple and efficient method for constructing an adenoviral cDNA expression library.

cDNA expression cloning is a powerful method for the identification of genes that are able to confer a selectable phenotype on specific cell types. An adenovirus vector is characterized by several advantages over plasmid DNA and retroviral vector-mediated gene transfer, such as broad host range and high infectivity. However, an expression cloning protocol using the adenovirus vector has not been reported. We describe here a simple and efficient method for constructing adenovirus cDNA expression libraries based on Cre-lox-mediated in vitro recombination between adenoviral shuttle plasmid cDNA libraries and adenoviral genomic DNA tagged with terminal protein. In a model experiment, EGFP clones present at the frequency of 0.003% in the shuttle plasmid library could be efficiently converted to adenoviral vector in a 6-cm dish under optimized conditions, indicating that high-complexity libraries harboring low-abundance cDNAs can be produced. The efficiency of this system was demonstrated by the isolation of cDNA for CD2 (frequency less than 1 in 0.3 x 10(4) transcripts in T cells) from the human T cells. This effective and versatile method can facilitate the functional identification of genes for a variety of purposes.

Adenoviridae↗