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Publications (9)

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    [Show abstract] [Hide abstract] ABSTRACT: Peritonitis carcinomatosa is an advanced and intractable state of gastrointestinal and ovarian cancer, where mechanistic elucidation might enable the development of more effective therapies. Peritoneal dissemination of this type of malignancy has been generally thought to initiate from "milky spots" of primitive lymphoid tissues in the peritoneal cavity. In this study, we offer evidence challenging this idea, based on the finding that tumor implantation and directional dissemination was not required for the presence of milky spots, but rather SCF/CXCL12-expressing niche-like cells located at the border regions of perivascular adipose tissue. Interestingly, we found that peritoneal cavity lavage fluid, which specifically contains peritoneal collagen type IV and plasma fibronectin, dramatically facilitated spheroid formation of murine and human colon cancer cells. Spheroid formation strongly induced the expression of CXCR4 in an Sp1-dependent manner to promote niche-directed metastasis. Notably, disrupting sphere formation or inhibiting Sp1 activity was sufficient to suppress tumor dissemination and potentiated chemosensitivity to 5-fluorouracil. Our findings illuminate mechanisms of peritoneal cancer dissemination and highlight the Sp1/CXCR4/CXCL12 signaling axis as a rational target for the development of therapeutics to manage this intractable form of malignancy. Cancer Res; 76(2); 1-11. ©2016 AACR.
    Full-text Article · Jan 2016 · Cancer Research
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    [Show abstract] [Hide abstract] ABSTRACT: BubR1, a cell cycle-related protein, is an essential component of the spindle checkpoint that regulates cell division. Mice with BubR1 expression reduced to 10% of the normal level display a phenotype characterized by progeria; however, the involvement of BubR1 in vascular diseases is still unknown. We generated mice in which BubR1 expression was reduced to 20% (BubR1(L/L) mice) of that in wild-type mice (BubR1(+/+)) to investigate the effects of BubR1 on arterial intimal hyperplasia. Ten-week-old male BubR1(L/L) and age-matched wild-type littermates (BubR1(+/+)) were used in this study. The left common carotid artery was ligated, and histopathologic examinations were conducted 4 weeks later. Bone marrow transplantation was also performed. Vascular smooth muscle cells (VSMCs) were isolated from the thoracic aorta to examine cell proliferation, migration, and cell cycle progression. Severe neointimal hyperplasia was observed after artery ligation in BubR1(+/+) mice, whereas BubR1(L/L) mice displayed nearly complete inhibition of neointimal hyperplasia. Bone marrow transplantation from all donors did not affect the reconstitution of 3 hematopoietic lineages, and neointimal hyperplasia was still suppressed after bone marrow transplantation from BubR1(+/+) mice to BubR1(L/L) mice. VSMC proliferation was impaired in BubR1(L/L) mice because of delayed entry into the S phase. VSMC migration was unaffected in these BubR1(L/L) mice. p38 mitogen-activated protein kinase-inhibited VSMCs showed low expression of BubR1, and BubR1-inhibited VSMCs showed low expression of p38. BubR1 may represent a new target molecule for treating pathological states of vascular remodeling, such as restenosis after angioplasty. © 2014 American Heart Association, Inc.
    Full-text Article · Dec 2014 · Arteriosclerosis Thrombosis and Vascular Biology
  • Conference Paper · Jul 2014
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    Satoru Saito · Yui Harada · Yosuke Morodomi · [...] · Yoshikazu Yonemitsu
    [Show abstract] [Hide abstract] ABSTRACT: Adoptive immunotherapy using natural killer (NK) cells has been a promising treatment for intractable malignancies; however, there remain a number of difficulties with respect to the shortage and limited anticancer potency of the effector cells. We here established a simple feeder-free method to generate purified (>90%) and highly activated NK cells from human peripheral blood-derived mononuclear cells (PBMCs). Among the several parameters, we found that simply 1) CD3-depletion, 2) high dose IL-2, and 3) use of a specific culture medium were sufficient to obtain highly purified, expanded (~200-fold) and activated CD3-/CD56+ NK cells from PBMCs that we named zenithal-NK cells (Z-NK). Almost all Z-NK cells expressed the lymphocyte-activated marker CD69, and showed dramatically high expression of activation receptors (i.e., NKG2D), interferon-γ, perforin and granzyme B. Importantly, only 2 hours of reaction at an effector/target ratio of 1:1 was sufficient to kill almost all K562 cells, and the antitumor activity was also replicated in tumor-bearing mice in vivo. Cytolysis was specific for various tumor cells, but not for normal cells, irrespective of MHC class I expression. These findings strongly indicate that Z-NK cells are purified, expanded, and near-fully activated human NK cells and warrant further investigation in a clinical setting.
    Full-text Article · Jul 2013 · Human Gene Therapy Methods
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    [Show abstract] [Hide abstract] ABSTRACT: Malignant pleural mesothelioma (MPM) is highly intractable and readily spreads throughout the surface of the pleural cavity, and these cells have been shown to express urokinase-type plasminogen activator receptor (uPAR). We here examined the potential of our new and powerful recombinant Sendai virus (rSeV), which shows uPAR-specific cell-to-cell fusion activity (rSeV/dMFct14 (uPA2), named "BioKnife"), for tumor cell killing in two independent orthotopic xenograft models of human. Multicycle treatment using BioKnife resulted in the efficient rescue of these models, in association with tumor-specific fusion and apoptosis. Such an effect was also seen on both MSTO-211H and H226 cells in vitro; however, we confirmed that the latter expressed uPAR but not uPA. Of interest, infection with BioKnife strongly facilitated the uPA release from H226 cells, and this effect was completely abolished by use of either pyrrolidine dithiocarbamate (PDTC) or BioKnife expressing the C-terminus-deleted dominant negative inhibitor for retinoic acid-inducible gene-I (RIG-IC), indicating that BioKnife-dependent expression of uPA was mediated by the RIG-I/nuclear factor-κB (NF-κB) axis, detecting RNA viral genome replication. Therefore, these results suggest a proof of concept that the tumor cell-killing mechanism via BioKnife may have significant potential to treat patients with MPM that is characterized by frequent uPAR expression in a clinical setting.
    Full-text Article · Feb 2012 · Molecular Therapy
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    [Show abstract] [Hide abstract] ABSTRACT: Dendritic cells (DCs) play a crucial role in maintaining the immune system. Though DC-based cancer immunotherapy has been suggested as a potential treatment for various kinds of malignancies, its clinical efficacies are still insufficient in many human trials. Issues that limit the clinical efficacy of DC-based immunotherapy, as well as the difficulty of the industrial production of DCs, are largely due to the limited number of autologous DCs available from each patient. We here established a possible breakthrough, a simple cytokine-based culture method to expand the log-scale order of functional human DCs. Floating cultivation of cord-blood CD34(+) cells under an optimized cytokine cocktail led these progenitor cells to stable log-scale proliferation and to DC differentiation. The expanded DCs had typical features of conventional myeloid DCs in vitro. Therefore, the concept of DC expansion should contribute significantly to the progress of DC immunotherapy.
    Full-text Article · Nov 2011 · Scientific Reports
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    [Show abstract] [Hide abstract] ABSTRACT: Supplemantal figure and table
    Full-text Dataset · Nov 2011
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    Takeshi Takano · Yoshikazu Yonemitsu · Satoru Saito · [...] · Yoshihiko Maehara
    [Show abstract] [Hide abstract] ABSTRACT: Intestinal damage after ischemia followed by revascularization, referred to as "ischemia-reperfusion (I/R) injury," is a devastating complication that can occur after acute superior mesenteric obstruction, or after both elective and emergent abdominal aortic surgery. Once an entire layer of intestine is involved in severe ischemia, the mortality rate reaches 90%; no effective medical treatment has been reported to date. Here, we demonstrate that a somatostatin analogue, octreotide, but not a free-radical scavenger, MCI-186, prevented death due to surgically induced intestinal I/R injury in rats. Superior mesenteric artery (SMA) of Male Sprague-Dawley rats, that received MCI-186 or octreotide, was surgically clamped, and then the clips were removed and SMA blood flow restored. Survival was assessed, and blood and small intestine were subjected to cell count, enzyme-linked immunosorbent assay (ELISA), Western blotting, and immunohistochemistry. Of interest, pretreatment with octreotide, but not with MCI-186, just before induced intestinal ischemia prompted the early expression of heme oxygenase-1 (HO-1) protein-associated accumulation of CD68-positive cells, a possible cellular source of HO-1. Inversely, the administration of tin protoporphyrin IX (SnPPN), a specific inhibitor of HO-1, completely abolished the therapeutic effects of octreotide, indicating that the favorable effects of octreotide against intestinal I/R injury is predominantly dependent on the early induction of HO-1. These results suggest that a somatostatin analogue may be useful in leading to an improvement of the prognosis of patients with intestinal I/R injury in the clinical setting.
    Full-text Article · Apr 2011 · Journal of Surgical Research
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    [Show abstract] [Hide abstract] ABSTRACT: Glioblastoma multiforme (GM), the most frequent primary malignant brain tumor, is highly invasive due to the expression of proteases, including urokinase-type plasminogen activator (uPA). Here, we show the potential of our new and powerful recombinant Sendai virus (rSeV) showing uPA-specific cell-to-cell fusion activity [rSeV/dMFct14 (uPA2), named "BioKnife"] for GM treatment, an effect that was synergistically enhanced by arming BioKnife with the interferon-β (IFN-β) gene. BioKnife killed human GM cell lines efficiently in a uPA-dependent fashion, and this killing was prevented by PA inhibitor-1. Rat gliosarcoma 9L cells expressing both uPA and its functional receptor uPAR (9L-L/R) exhibited high uPA activity on the cellular surface and were highly susceptible to BioKnife. Although parent 9L cells (9L-P) were resistant to BioKnife and to BioKnife expressing IFN-β (BioKnife-IFNβ), cell-cell fusion of 9L-L/R strongly facilitated the expression of IFN-β, and in turn, IFN-β significantly accelerated the fusion activity of BioKnife. A similar synergy was seen in a rat orthotopic brain GM model with 9L-L/R in vivo; therefore, these results suggest that BioKnife-IFNβ may have significant potential to improve the survival of GM patients in a clinical setting.
    Full-text Article · Oct 2010 · Molecular Therapy