Publications (51)131.99 Total impact
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Article: In vivo gene transfer using pDNA/chitosan/chondroitin sulfate ternary complexes: Influence of chondroitin sulfate on the stability of freeze-dried complexes and transgene expression in vivo.
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ABSTRACT: BACKGROUND: Chitosan has been investigated as a promising non-viral vector. However, several problems still remain such as relatively low transfection efficiency and instabilities under physiological conditions. We previously demonstrated that a chondroitin sulfate (CS) coating enhanced the transfection efficiency and physicochemical stability of pDNA/chitosan complexes in vitro. In this study, the effects of coating pDNA/chitosan complexes with CS on stability in freeze-dry rehydration processes and gene expression in vivo were investigated. METHODS: Freeze-drying storage at -20 °C, 4 °C, or room temperature, freezing storage at -20 °C, or liquid storage at 4 °C or room temperature were examined for preservation conditions of pDNA/chitosan/CS ternary complexes by gel retardation assay, measurements of sizes and zeta potentials, and luciferase assay. Moreover, to elucidate the transfection efficiency of the ternary complexes in vivo, suicide gene therapy was carried out in Huh-7-implanted mice using herpes simplex virus thymidine kinase coding pDNA (pTK) and ganciclovir (GCV). RESULTS: The freeze-dried pDNA/chitosan/CS ternary complexes showed sufficient cell transfection ability in vitro and in vivo. In addition, ternary complexes were associated with significant suppression of tumor growth and a histopathologically high anti-tumor effect by intratumoral injection to tumor-bearing mice. CONCLUSIONS: The CS coating enhanced preservation stability of the pDNA/chitosan complexes after freeze-drying-rehydration and their transgene expression in vivo. Copyright © 2013 John Wiley & Sons, Ltd.The Journal of Gene Medicine 01/2013; · 2.48 Impact Factor -
Article: The density of GM1 in nanoclusters is a critical factor in the formation of a spherical assembly of amyloid β-protein on synaptic plasma membranes.
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ABSTRACT: The deposition of amyloid β-protein (Aβ) is a pathological hallmark of Alzheimer's disease (AD). The ganglioside-enriched microdomains (ganglioside clusters) in presynaptic neuronal membranes play a key role in the initiation of the Aβ assembly process. However, not all ganglioside clusters accelerate Aβ assembly. In the present study, we directly observed a spherical Aβ in an atomic force microscopic study on the morphology of a reconstituted lipid bilayer composed of lipids that were extracted from a detergent-resistant membrane microdomain (DRM) fraction of synaptosomes prepared from aged mouse brain. The Aβ assembly was generated on a distinctive GM1 domain, which was characterized as the Aβ-sensitive ganglioside nanocluster (ASIGN). By using an artificial GM1 cluster-binding peptide, ASIGN was found to have a high density of GM1, therefore there would be a critical density of GM1 in nanoclusters to induce Aβ binding and assembly. These results suggest that ganglioside-bound Aβ (GAβ), which acts as an endogenous seed for Aβ fibril formation in AD brains, is generated on ASIGN on synaptosomal membranes.Langmuir 01/2013; · 4.19 Impact Factor -
Article: Three-dimensional expansion using plasma-medium gel with fragmin/protamine nanoparticles and fgf-2 to stimulate adipose-derived stromal cells and bone marrow-derived mesenchymal stem cells.
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ABSTRACT: Fragmin/protamine nanoparticles (F/P NPs) have been used as carriers for the preservation and controlled release of fibroblast growth factor (FGF)-2 and various cytokines in human plasma (HP). This study tested an HP-Dulbecco's modified Eagle's medium (DMEM) gel as a three-dimensional (3D) culture for the expansion of adipose tissue-derived multilineage stromal cells (ASCs) and bone marrow-derived mesenchymal stem cells (BMSCs). The growth of these cells improved in 3D culture using low-concentration HP (2%)-DMEM gel with 0.1 mg/mL F/P NPs and 5 ng/mL FGF-2 without animal serum in comparison to two-dimensional (2D) culture using a low-concentration human serum (2%)-DMEM containing 5 ng/mL FGF-2 on F/P NPs-coated plates. ASCs and BMSCs, which were expanded in the low-concentration HP-DMEM gel with F/P NPs and FGF-2, maintained their multilineage potential for differentiation into adipocytes or osteoblasts similar to the 2D cultured cells. Furthermore, flow cytometric analyses showed that the phenotypic markers which were positive for CD44, CD90, and CD105 (>80%) and negative for CD34 and CD45 (<1%) were well maintained in both 2D and 3D cultures after 7 days. Thus, this 3D culture system in low-concentration HP-DMEM gel with F/P NPs and FGF-2 provided an effective and safe method for the expansion of both cell types without using animal serum.BioResearch open access. 12/2012; 1(6):314-23. -
Dataset: 2011BBA HGF
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Article: Involvement of Ext1 and heparanase in migration of mouse FBJ osteosarcoma cells.
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ABSTRACT: To know the involvement of glycosaminoglycans (GAGs) in the metastasis of mouse FBJ osteosarcoma cells, N ( α )-lauroyl-O-(β-D-xylopyranosyl)-L-serinamide (Xyl-Ser-C12), which initiates elongation of GAG chains using the glycan biosynthesis system in cells, was administered to FBJ cells with different metastatic capacities. Production of glycosylated products derived from Xyl-Ser-C12, especially heparan sulfate (HS) GAG-type oligosaccharides such as GalNAc-GlcA-GlcNAc-GlcA-Gal-Gal-Xyl-Ser-C12, was indicated in poorly metastatic FBJ-S1 cells more than in highly metastatic FBJ-LL cells by LC-MS. The results of RT-PCR revealed that HS synthases, Ext1 and Ext2, were expressed in FBJ-S1 cells more than in FBJ-LL cells. Furthermore, siRNA against Ext1 suppressed the expression of HS and enhanced the motility of FBJ-S1 cells. In addition, the expression of heparanase (HPSE) was enhanced in Ext-1-knockdown FBJ-S1 cells, and responsible for the increase in cell motility caused by the down-regulation of Ext1 expression. Our data provide the first evidence that Ext1 regulates the expression of HPSE and also indicated that levels of Ext1 and HPSE influenced the motility of FBJ cells.Molecular and Cellular Biochemistry 10/2012; · 2.06 Impact Factor -
Article: Fragmin/protamine microparticles to adsorb and protect HGF and to function as local HGF carriers in vivo.
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ABSTRACT: The clinical efficacy of hepatocyte growth factor (HGF) in tissue repair can be greatly enhanced by high affinity, biocompatible drug carriers that maintain the bioactivity and regulate release at the target site. We produced 0.5-3.0μm fragmin (low molecular weight heparin)/protamine microparticles (F/P MPs) as carriers for the controlled release of HGF. F/P MPs immobilized more than 3μg of HGF per mg of MPs and gradually released the absorbed HGF into the medium with a half-release time of approximately 5days. Compared with HGF alone, HGF-containing F/P MPs substantially enhanced the mitogenic effect of HGF on cultured human microvascular endothelial cells, by prolonging the biological half-life, and its conjugation to F/P MPs protected HGF from heat and proteolytic inactivation. F/P MPs disappeared 8days after subcutaneous injection in mice, suggesting that they are rapidly biodegraded. Furthermore, the number of large (diameter ⩾200μm or containing ⩾100 erythrocytes) and medium (diameter 20-200μm or containing 10-100 erythrocytes) lumen capillaries 8days after injection of HGF-containing F/P MPs was significantly higher than that after injection of HGF or F/P MPs alone. Furthermore, the number of small (diameter ⩽20μm or containing 1-10 erythrocytes) lumen capillaries was significantly higher 4days after injection of HGF-containing F/P MPs. This increased angiogenic activity of HGF in vivo is probably due to both sustained local release and protection against biodegradation by the F/P MPs. Thus, F/P MPs may be useful and safe HGF carriers that facilitate cell proliferation and vascularization at sites of tissue damage.Acta biomaterialia 08/2012; · 3.98 Impact Factor -
Article: Calcium regulates caveolin-1 expression at the transcriptional level.
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ABSTRACT: Caveolin-1, an indispensable component of caveolae serving as a transformation suppressor protein, is highly expressed in poorly metastatic mouse osteosarcoma FBJ-S1 cells while highly metastatic FBJ-LL cells express low levels of caveolin-1. Calcium concentration is higher in FBJ-S1 cells than in FBJ-LL cells; therefore, we investigated the possibility that calcium signaling positively regulates caveolin-1 in mouse FBJ-S1 cells. When cells were treated with the calcium channel blocker nifedipine, cyclosporin A (a calcineurin inhibitor), or INCA-6 (a nuclear factor of activated T-cells [NFAT] inhibitor), caveolin-1 expression at the mRNA and protein levels decreased. RNA silencing of voltage-dependent L-type calcium channel subunit alpha-1C resulted in suppression of caveolin-1 expression. This novel caveolin-1 regulation pathway was also identified in mouse NIH 3T3 cells and Lewis lung carcinoma cells. These results indicate that caveolin-1 is positively regulated at the transcriptional level through a novel calcium signaling pathway mediated by L-type calcium channel/Ca(2+)/calcineurin/NFAT.Biochemical and Biophysical Research Communications 08/2012; 426(3):334-41. · 2.48 Impact Factor -
Article: Glycosylation of N(α)-lauryl-O-(β-d-xylopyranosyl)-l-serinamide as a saccharide primer in cells.
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ABSTRACT: N(α)-Lauryl-O-(β-d-xylopyranosyl)-l-serinamide (Xyl-Ser-C12) was synthesized as a saccharide primer to obtain oligosaccharides of glycosaminoglycan using the glycan biosynthetic potential of mouse osteosarcoma FBJ-S1 cells and Chinese hamster ovary (CHO) cells. The glycosylated products secreted into the culture medium were collected and analyzed by liquid chromatography-mass spectrometry and glycosidase digestion. The structure of the Xyl-Ser-C12 derivatives was investigated. Several glycosaminoglycan-type oligosaccharides, such as GalNAc-(GlcA-GlcNAc)(n)-GlcA-Gal-Gal-Xyl-Ser-C12, were detected, and identified as intermediates of the biosynthesis of heparan sulfate glycosaminoglycans. Xyl-Ser-C12 exhibited greater acceptor activity for the glycosylation of glycosaminoglycan-type oligosaccharides than p-nitrophenyl-β-d-xylopyranoside.Carbohydrate research 08/2012; 361C:33-40. · 2.03 Impact Factor -
Article: The effects of coating pDNA/chitosan complexes with chondroitin sulfate on physicochemical characteristics and cell transfection.
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ABSTRACT: pDNA/chitosan complexes have been investigated as promising non-viral vectors for gene delivery. However, an increase in transfection efficiency and enhancement of physicochemical stability are required for their practical use. In this study, chondroitin sulfate (CS) was employed as a coating agent to increase the stability and transfection efficiency of a pDNA/chitosan complex. The pDNA/chitosan/CS ternary complexes formed with six kinds of CSs having different limiting viscosities (0.2-1.6) and sulfation degrees (5.0-7.0%) showed considerable differences in particle size, surface charge, and morphology. Among them, CS having a medium limiting viscosity (0.5-0.6) and a high sulfation degree (6.9%) showed significant enhancements in cell transfection efficiency. Analyses of cellular uptake and intracellular trafficking revealed that increased cellular uptake via macropinocytosis, together with reduced entry into lysosomes, may explain the promotion of transfection efficiency of ternary complexes.Biomaterials 07/2012; 33(29):7251-60. · 7.40 Impact Factor -
Article: Fragmin/Protamine Microparticles (F/P MPs) as Cell Carriers Enhance the Formation and Growth of Tumors In Vivo
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ABSTRACT: Mixing a low-molecular-weight heparin (e.g., fragmin) with protamine results in the formation of water-insoluble fragmin/protamine Mixing a low-molecular-weight heparin (e.g., fragmin) with protamine results in the formation of water-insoluble fragmin/protamine microparticles (F/P MPs) approximately 0.5–3μm in diameter. In this study, we investigated the ability of F/P MPs to improve the viability of Lewis lung (3LL) cancer cells, microparticles (F/P MPs) approximately 0.5–3μm in diameter. In this study, we investigated the ability of F/P MPs to improve the viability of Lewis lung (3LL) cancer cells, B16 (B16) melanoma cells, and a human hepatoma (Huh7) cell line in a suspension culture, and the ability of F/P MPs to enhance B16 (B16) melanoma cells, and a human hepatoma (Huh7) cell line in a suspension culture, and the ability of F/P MPs to enhance tumor take rate and growth in vivo. F/P MPs rapidly bound to the surface of the cells. The interaction of the cells with F/P MPs induced formations of the tumor tumor take rate and growth in vivo. F/P MPs rapidly bound to the surface of the cells. The interaction of the cells with F/P MPs induced formations of the tumor cell/F/P MP aggregates and maintained the viability of those cells in suspension for at least 3 days. The addition of F/P cell/F/P MP aggregates and maintained the viability of those cells in suspension for at least 3 days. The addition of F/P MPs with FGF-2 significantly enhanced the growth rate of the cells in a fetal bovine serum (FBS)-free medium. The tumor cell/F/P MPs with FGF-2 significantly enhanced the growth rate of the cells in a fetal bovine serum (FBS)-free medium. The tumor cell/F/P MP aggregates, which were subcutaneously injected into the backs of mice, significantly stimulated the formation and growth MP aggregates, which were subcutaneously injected into the backs of mice, significantly stimulated the formation and growth of subcutaneous tumors consisting of 3LL, B16, and Huh7 cells. Furthermore, the tumors produced by injection of 7.5×105 Huh7 into nude mice did grow only with F/P MPs. Thus F/P MPs can utilize as cell carrier for tumor cell transplantation. of subcutaneous tumors consisting of 3LL, B16, and Huh7 cells. Furthermore, the tumors produced by injection of 7.5×105 Huh7 into nude mice did grow only with F/P MPs. Thus F/P MPs can utilize as cell carrier for tumor cell transplantation. KeywordsTumor cell transplantation–Cell carrier–Cell/F/P MP aggregate–Fragmin/protamine microparticles–Tumor growth KeywordsTumor cell transplantation–Cell carrier–Cell/F/P MP aggregate–Fragmin/protamine microparticles–Tumor growthCellular and Molecular Bioengineering 04/2012; 4(3):476-483. · 1.95 Impact Factor -
Article: Effective expansion of human adipose-derived stromal cells and bone marrow-derived mesenchymal stem cells cultured on a fragmin/protamine nanoparticles-coated substratum with human platelet-rich plasma.
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ABSTRACT: Fragmin/protamine nanoparticles (F/P NPs) can be stably coated onto plastic surfaces and used as a substratum for the absorption and controlled release of growth factors (GFs) secreted from human platelet-rich plasma (PRP). In this study, we investigated the capability of F/P NP-coated plates to act as a substratum for the proliferation of human adipose-derived stromal cells (ASCs) and bone marrow-derived mesenchymal stem cells (BMSCs) with GFs in PRP. Both cell types adhered well to the F/P NP-coated plates and grew optimally, with a doubling time of 30 and 32 h in low-concentration PRP (0.5%) medium supplemented with 5 ng/ml fibroblast growth factor-2 (FGF-2) on the F/P NP-coated plates. These cells maintained their multilineage potential for differentiation into adipocytes or osteoblasts. Furthermore, ASCs and BMSCs grew well in medium without PRP and FGF-2 on F/P NP-coated plates pretreated with PRP and FGF-2 in a concentration-dependent manner. Thus, F/P NP-coated plates are a useful substratum for the adherence and proliferation of ASCs and BMSCs in low-concentration PRP medium supplemented with FGF-2. No xenogeneic serum is required. Copyright © 2012 John Wiley & Sons, Ltd.Journal of Tissue Engineering and Regenerative Medicine 03/2012; · 3.28 Impact Factor -
Article: Brain insulin resistance accelerates Aβ fibrillogenesis by inducing GM1 ganglioside clustering in the presynaptic membranes.
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ABSTRACT: Type 2 diabetes mellitus is thought to be a significant risk factor for Alzheimer's disease. Insulin resistance also affects the central nervous system by regulating key processes, such as neuronal survival and longevity, learning and memory. However, the mechanisms underlying these effects remain uncertain. To investigate whether insulin resistance is associated with the assembly of amyloid β-protein (Aβ) at the cell surface of neurons, we inhibited insulin-signalling pathways of primary neurons. The treatments of insulin receptor (IR)-knockdown and a phosphatidylinositol 3-kinase inhibitor (LY294002), but not an extracellular signal-regulated kinase inhibitor, induced an increase in GM1 ganglioside (GM1) levels in detergent-resistant membrane microdomains of the neurons. The aged db/db mouse brain exhibited reduction in IR expression and phosphorylation of Akt, which later induced an increase in the high-density GM1-clusters on synaptosomes. Neurons treated with IR knockdown or LY294002, and synaptosomes of the aged db/db mouse brains markedly accelerated an assembly of Aβs. These results suggest that ageing and peripheral insulin resistance induce brain insulin resistance, which accelerates the assembly of Aβs by increasing and clustering of GM1 in detergent-resistant membrane microdomains of neuronal membranes.Journal of Neurochemistry 01/2012; 121(4):619-28. · 4.06 Impact Factor -
Article: Physicochemical properties of pDNA/chitosan complexes as gene delivery systems.
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ABSTRACT: Successful gene therapy depends on the development of effective gene carriers. Naturally occurring chitosan has been employed widely as a non-viral gene carrier because of its low toxicity, low immunogenicity, biocompatibility, and biodegradability. In this review, we summarize the utilization of chitosan, modified chitosan, and chitosan-containing ternary complexes as gene carriers. In particular, we discuss the influence of the physicochemical features of pDNA/chitosan complexes on their functions, such as stability and gene transfer into cells.Current Drug Discovery Technologies 07/2011; 8(4):329-39. -
Article: Ganglioside GD1a negatively regulates hepatocyte growth factor expression through caveolin-1 at the transcriptional level in murine osteosarcoma cells.
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ABSTRACT: Hepatocyte growth factor (HGF) is a mesenchyme-derived, multifunctional protein that is implicated in tumor growth and invasive behavior. Some tumor cells express both HGF and its receptor MET, forming an autocrine loop that permanently activates it. Ganglioside GD1a suppresses metastatic capacity in murine FBJ osteosarcoma cells and MET phosphorylation activated by HGF binding, but the signaling pathway controlling HGF production has not been fully explored. Expression of HGF, caveolins, or MET of the cells that had been transfected with siRNA or cDNA directed to GM2/GD2 synthase, caveolin-1 or HGF was determined by semi-quantitative RT-PCR and Western blots. HGF expression in highly metastatic, GD1a-deficient FBJ-LL cells was higher than that in the poorly metastatic, GD1a-rich FBJ-S1 cells. Transfection with GM2/GD2 synthase cDNA increased GD1a levels in FBJ-LL cells and suppressed HGF expression. Treatment with siRNAs directed toward GM2/GD2 synthase in FBJ-S1 cells reduced gangliosides and augmented HGF expression. GD1a was found to be the only ganglioside species suppressing HGF expression upon addition to FBJ-LL cells. HGF expression was decreased by GD1a addition to FBJ-LL cells after 48h, enough to induce caveolin-1 expression. Silencing caveolin-1 up-regulated HGF, and the re-introduction of caveolin-1 cDNA decreased HGF expression. Caveolin-1 suppressed MET phosphorylation. We also found GD1a regulation of HGF in Lewis lung carcinoma cells. HGF expression was negatively regulated by GD1a through caveolin-1 at the transcriptional level via the suppression of MET phosphorylation. This is the first report that ganglioside GD1a negatively regulates HGF expression through caveolin-1.Biochimica et Biophysica Acta 04/2011; 1810(8):759-68. · 4.66 Impact Factor -
Article: GM3 suppresses anchorage-independent growth via Rho GDP dissociation inhibitor beta in melanoma B16 cells.
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ABSTRACT: Ly-GDI, Rho GTPase dissociation inhibitor beta, was found to be expressed parallel to the GM3 level in mouse B16 cells whose GM3 contents were modified by B4galt6 sense, B4galt6 antisense cDNA, or St3galt5 siRNA transfection. Ly-GDI expression was increased on GM3 addition to these cells and decreased with D-PDMP treatment, a glucosylceramide synthesis inhibitor. Suppression of GM3 or Ly-GDI by RNAi was concomitantly associated with an increase in anchorage-independent growth in soft agar. These results clearly indicate that GM3 suppresses anchorage-independent growth through Ly-GDI. GM3 signals regulating Ly-GDI expression was inhibited by LY294002, siRNA against Akt1 and Akt2 and rapamycin, showing that GM3 signals are transduced via the PI3K/Akt/mTOR pathway. Either siRNA towards Rictor or Raptor suppressed Ly-GDI expression. The Raptor siRNA suppressed the effects of GM3 on Ly-GDI expression and Akt phosphorylation at Thr(308) , suggesting GM3 signals to be transduced to mTOR-Raptor and Akt-Thr(308) , leading to Ly-GDI stimulation. siRNA targeting Pdpk1 reduced Akt phosphorylation at Thr(308) and rendered the cells insensitive to GM3 stimulation, indicating that Akt-Thr(308) plays a critical role in the pathway. The components aligned in this pathway showed similar effects on anchorage-independent growth as GM3 and Ly-GDI. Taken together, GM3 signals are transduced in B16 cells through PI3K, Pdpk1, Akt(Thr308) and the mTOR/Raptor pathway, leading to enhanced expression of Ly-GDI mRNA, which in turn suppresses anchorage-independent growth in melanoma B16 cells.Cancer Science 04/2011; 102(8):1476-85. · 3.33 Impact Factor -
Article: Accelerated biosynthesis of neolacto-series glycosphingolipids in differentiated mouse embryonal carcinoma F9 cells detected by using dodecyl N-acetylglucosaminide as a saccharide primer.
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ABSTRACT: Using dodecyl N-acetylglucosaminide (GlcNAc-C12) as a saccharide primer, we investigated the biosynthetic changes of neolacto-series glycosphingolipids (GSLs) in mouse embryonal carcinoma F9 cells during differentiation induced by retinoic acid plus dibutyryl cyclic AMP (RA/dbcAMP). In the differentiated cells, the glycosylation of GlcNAc-C12 was greatly enhanced. The sugar compositions of glycosylated primers were assigned as Hex-GlcNAc, [Hex](2)-GlcNAc, [Hex](2)[HexNAc]-GlcNAc, and [NeuAc][Hex]-GlcNAc by liquid chromatography-tandem mass spectrometry. The detection of augmented biosynthesis of endogenous sialylparagloboside indicated that [NeuAc][Hex]-GlcNAc was predicted to be the non-reducing end trisaccharide of sialylparagloboside. The transcription of B3gnt5, B4galt1, Ggta1, Fut4 and St3gal6, encoding glycosyltransferases involved in the neolacto-series glycosphingolipids biosynthesis, was increased, whereas that of Fut9 and St6galI was decreased after RA/dbcAMP treatment. Furthermore, the sialyltransferase activity of ST3GalVI sialylating paragloboside was enhanced with the increase in St3gal6 expression. Since most stage-specific embryonic antigen-1 (SSEA-1) active determinants are carried by glycoproteins in F9 cells, the changes in glycolipid metabolism do not seem to be closely related to loss of cell surface SSEA-1 expression upon F9 differentiation. These results indicate that RA/dbcAMP treatment activates the biosynthesis of neolacto-series GSL and enhances sialylation of paragloboside in F9 cells with down-regulation of Fut9 expression.Journal of biochemistry 03/2011; 149(3):321-30. · 1.95 Impact Factor -
Article: GM3 Upregulation of matrix metalloproteinase-9 possibly through PI3K, AKT, RICTOR, RHOGDI-2, and TNF-A pathways in mouse melanoma B16 cells.
Advances in experimental medicine and biology 01/2011; 705:335-48. · 1.09 Impact Factor -
Article: Selective Expansion of CD34+ Cells from Mouse Bone Marrow Cultured on LH/P MP-Coated Plates with Adequate Cytokines.
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ABSTRACT: Low-molecular-weight heparin/protamine microparticles (LH/P MPs) serve as carriers for controlled release of heparin-binding cytokines. LH/P MPs were stably coated onto plastic surfaces by drying. The purpose of this study is to evaluate a culture method for selective expansion of CD34+ cells using LH/P MPs as cytokine-binding matrix. Ficoll-purified mouse bone marrow cells (mouse FP-BMCs) containing CD34+ cells were cultured on LH/P MP-coated plates in the presence of stem cell factor (SCF), thrombopoietin (Tpo), and Flt-3 ligand (Flt-3) in hematopoietic progenitor growth medium (HPGM) supplemented with 4% heat-inactivated fetal bovine serum (FBS). After 8 days of culture, the total cell count increased 4.6-fold, and flow cytometry analyses revealed that 23.8% of the initial cells and 57.4% of the expanded cells were CD34 positive. Therefore, CD34+ cells were estimated to have increased 11.0-fold. In contrast, cultured CD34+ cells on uncoated tissue culture plates increased 5.8-fold in an identical medium.Journal of tissue engineering. 01/2011; 2(1):2041731411425419. -
Article: Neuroblastoma cells can be classified according to glycosphingolipid expression profiles identified by liquid chromatography-tandem mass spectrometry.
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ABSTRACT: It is hoped that the gangliosides contained in neuroblastomas (NBs) can be used as outcome predictors. We used liquid chromatography-tandem mass spectrometry (LC-MS) to analyze the gangliosides expressed in 11 NB cell lines. LC-MS analysis detected a number of gangliosides, including acetylated forms, with significantly higher sensitivity than conventional high-performance thin-layer chromatography analysis, and the results revealed that the expression profiles of the gangliosides GD1a, GD2, and acetylated GD2 differed according to the NB cell line. Hierarchical clustering based on the ganglioside expression profiles obtained by LC-MS analysis revealed that the NB cell lines could be classified into three types according to their expression of these three gangliosides: A-type characterized by high expression of GD1a and low or no expression of GD2/acetylated GD2, B-type characterized by low or no expression of GD1a and high expression of GD2/acetylated GD2, and AB-type characterized by expression of both GD1a and GD2/acetylated GD2. Interestingly, all three MYCN non-amplified cell lines were classified into the A-type. The classification was found to be correlated with mRNA expression of ganglioside synthase and neural-differentiation-related genes. The results of this study indicate that LC-MS analysis is useful as a tool for glycosphingolipid research on malignancies.International Journal of Oncology 11/2010; 37(5):1279-88. · 2.40 Impact Factor -
Article: Ganglioside GD1a suppression of NOS2 expression via ERK1 pathway in mouse osteosarcoma FBJ cells.
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ABSTRACT: Inducible nitric oxide synthase (NOS2) is over-expressed in a number of tumors and implicated in tumor growth and metastasis. Murine FBJ osteosarcoma-derived FBJ-S1 cells are poorly metastatic and express the ganglioside GD1a, whereas highly metastatic FBJ-LL cells only slightly express this ganglioside. The present study demonstrates that NOS2 is more highly expressed in FBJ-LL cells compared to FBJ-S1 cells. By manipulating GM2/GD2 synthase expression or adding exogenous GD1a, GD1a inversely regulated NOS2 at the transcriptional level. GT1b suppressed NOS2 to the same extent as GD1a. Silencing NOS2 inhibited proliferation, migration, and anchorage-independent growth of FBJ-LL cells, suggesting that the metastatic properties of FBJ-LL cells are associated with NOS2. MEK1/2 inhibitor (U0126) increased NOS2 expression, whereas GD1a treatment decreased it. Co-treating the cells with GD1a and U0126 blocked the inhibition of NOS2 expression, suggesting that the GD1a signal is mediated by ERK1/2. NOS2 expression increased when ERK1, but not ERK2, was silenced, and GD1a did not suppress NOS2 expression in cells treated with another MEK1/2 inhibitor PD98059, suggesting that ERK1 phosphorylation is indispensable for the GD1a signal suppressing NOS2.Journal of Cellular Biochemistry 08/2010; 110(5):1165-74. · 2.87 Impact Factor
Top co-authors
Top Journals
Institutions
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2002–2013
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Keio University
- • Department of Biosciences and Informatics
- • Department of Applied Chemistry
Tokyo, Tokyo-to, Japan
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2006–2012
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Shenyang Pharmaceutical University
- School of Life Science and Biopharmaceutics
Shenyang, Liaoning, China
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2011
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National Defense Medical College
Tokorozawa, Saitama-ken, Japan
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2004–2005
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The University of Tokyo
- Institute of Industrial Science
Tokyo, Tokyo-to, Japan
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2001
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Johns Hopkins University
Baltimore, MD, USA
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1998–2001
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Tokyo Institute of Technology
- Department of Biomolecular Engineering
Tokyo, Tokyo-to, Japan
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1999
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Kitasato University
Tokyo, Tokyo-to, Japan
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