Kazuhiro Yoshikawa

Kinki University, Ōsaka-shi, Osaka-fu, Japan

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Publications (32)85.31 Total impact

  • Article: Effects of the Rho kinase inhibitor, hydroxyfasudil, on bladder dysfunction and inflammation in rats with HCl-induced cystitis.
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    ABSTRACT: OBJECTIVE: To evaluate the effect of the Rho kinase inhibitor, hydroxyfasudil, on bladder function in a rat model of HCl-induced chemical cystitis, and to elucidate the possible mechanisms associated with its therapeutic effect. METHODS: Female Sprague-Dawley rats with HCl-induced cystitis were given hydroxyfasudil (10 mg/kg, i.p.) for 7 days. Treatment efficacy was determined by comparing bladder function and histopathology to sham and untreated control rats. Bladder function was determined by cystometric analysis. Rho kinase activity was determined by quantitative reverse transcription polymerase chain reaction and signal inhibition of downstream Ras homolog member A/Rho kinase signaling molecules by western blot and immunohistochemistry. RESULTS: Treatment with hydroxyfasudil significantly improved bladder intercontraction intervals. Rats treated with hydroxyfasudil also showed a significant reduction of histopathological features associated with cystitis. Western blot and immunohistochemistry findings showed that hydroxyfasudil inhibited downstream molecules of Rho kinase that ameliorated changes associated with HCl-induced chemical cystitis, such as inflammatory cell recruitment and smooth muscle cell proliferation. CONCLUSION: The findings from the present study suggest a promising therapeutic role for hydroxyfasudil in bladder inflammation associated with cystitis.
    International Journal of Urology 02/2013; · 1.75 Impact Factor
  • Article: Systemic transduction of p16INK4A antitumor peptide inhibits the growth of MBT-2 mouse bladder tumor cell line grafts.
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    ABSTRACT: p16INK4a (p16), a key molecule in bladder tumor development, inhibits the activities of cyclin-dependent kinases (CDKs) and maintains the retinoblastoma protein (pRb) in its active hypophosphorylated state. Following the finding that the p16 antitumor peptide dramatically inhibits the growth of aggressive leukemia̸lymphoma through the restoration of p16 function using the Wr-T peptide transporter system, in this study, we developed a systemic therapy using mouse‑p16 peptide (m‑p16) in subcutaneous p16‑null mouse bladder tumors. In vitro analysis showed that the growth of p16‑null bladder tumor cells and the hyperphosphorylation of their pRbs were inhibited by p16 transduction in a concentration‑dependent manner. In an animal model, p16‑null MBT‑2 cells were injected subcutaneously into KSN/SKC nude mice. The systemic delivery of the m‑p16 peptide using Wr‑T by cardiac injection significantly inhibited the growth of solid MBT‑2 tumors compared with the control phosphate‑buffered saline (PBS) injection. Histological examination by TUNEL staining revealed that apoptosis was increased and pRb phosphorylation was inhibited. Thus, the systemic peptide delivery of p16 restores the hypophosphorylation of pRb and may be a useful tool for the treatment of bladder tumors.
    International Journal of Oncology 12/2012; · 2.40 Impact Factor
  • Article: A new molecular targeted therapeutic approach for renal cell carcinoma with a p16 functional peptide using a novel transporter system.
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    ABSTRACT: Molecular targeting agents have become formidable anticancer weapons showing much promise against refractory tumors and functional peptides and are among the more desirable of these nanobio-tools. Intracellular delivery of multiple functional peptides forms the basis for a potent, non-invasive mode of delivery, providing distinctive therapeutic advantages. We examine the growth suppression efficiency of human renal cell carcinoma (RCC) by single-peptide targeting. We simultaneously introduced p16INK4a tumor suppressor peptides by Wr-T-mediated peptide delivery. Wr-T-mediated transport of p16INK4a functional peptide into 10 RCC lines, lacking expression of the p16INK4a molecule, reversed the specific loss of p16 function, thereby drastically inhibiting tumor growth in all but 3 lines by >95% within the first 96 h. In vivo analysis using SK-RC-7 RCC xenografts in nude mice demonstrated tumor growth inhibition by the p16INK4a peptide alone, however, inoculation of Wr-T and the p16INK4a functional peptide mixture, via the heart resulted in complete tumor regression. Thus, restoration of tumor suppressor function with Wr-T peptide delivery represents a powerful approach, with mechanistic implications for the development of efficacious molecular targeting therapeutics against intractable RCC.
    Oncology Reports 08/2011; 26(2):327-33. · 1.84 Impact Factor
  • Article: Clinicopathological significance of carbonic anhydrase 9, glucose transporter-1, Ki-67 and p53 expression in oral squamous cell carcinoma.
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    ABSTRACT: Carbonic anhydrase 9 (CA9) is a glycoprotein present on the surface of cell membranes. It is expressed in 90% of renal cancer cells, but not in normal kidney tissue. Immunotherapy targeting CA9 is underway, and our group has also conducted a clinical trial using CA9 as a cancer vaccine and confirmed the induction of cytotoxic T lymphocytes, with efficacy in some cases. Expression of CA9 antigen in oral cancer has not been reported in Japan, but our results indicate that immunotherapy targeting CA9 might be possible. We immunohistochemically observed the expression of antigens such as CA9, Ki-67, glucose transporter-1 (GLUT-1) and p53 in 107 subjects with oral squamous cell carcinoma, and examined their correlation with clinicopathological parameters. Immunostaining analysis showed expression of CA9 in 98% of oral cancer subjects, and the survival rate was significantly lower in subjects with CA9 antigen expression in 50% or more cells (P<0.05). Subjects with poorly differentiated, T4 and lymph node metastasis, or Stage IV cancer with high CA9 expression (≥50%) had a worse outcome than those with low CA9 expression. Although GLUT-1 expression was observed in 98% of subjects, similarly to CA9 expression, no significant correlation between its expression and the survival rate was seen. However, subjects with lymph node metastasis had significantly higher GLUT-1 expression, demonstrating that GLUT-1 could be an indicator of lymph node metastasis. Ki-67 was expressed in 92% of subjects, but no correlation with outcome was observed. Expression of p53 was noted in 78% of subjects, and it was found that many oral cancers have p53 genetic abnormalities, but no correlation between p53 and outcome was observed. It was confirmed that CA9 antigen is expressed in most oral cancer subjects, suggesting the possibility of immunotherapy targeting CA9 antigen in oral cancer.
    Oncology Reports 03/2011; 25(5):1227-33. · 1.84 Impact Factor
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    Article: Identification of novel biomarker candidates by proteomic analysis of cerebrospinal fluid from patients with moyamoya disease using SELDI-TOF-MS.
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    ABSTRACT: Moyamoya disease (MMD) is an uncommon cerebrovascular condition with unknown etiology characterized by slowly progressive stenosis or occlusion of the bilateral internal carotid arteries associated with an abnormal vascular network. MMD is a major cause of stroke, specifically in the younger population. Diagnosis is based on only radiological features as no other clinical data are available. The purpose of this study was to identify novel biomarker candidate proteins differentially expressed in the cerebrospinal fluid (CSF) of patients with MMD using proteomic analysis. For detection of biomarkers, CSF samples were obtained from 20 patients with MMD and 12 control patients. Mass spectral data were generated by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) with an anion exchange chip in three different buffer conditions. After expression difference mapping was undertaken using the obtained protein profiles, a comparative analysis was performed. A statistically significant number of proteins (34) were recognized as single biomarker candidate proteins which were differentially detected in the CSF of patients with MMD, compared to the control patients (p < 0.05). All peak intensity profiles of the biomarker candidates underwent classification and regression tree (CART) analysis to produce prediction models. Two important biomarkers could successfully classify the patients with MMD and control patients. In this study, several novel biomarker candidate proteins differentially expressed in the CSF of patients with MMD were identified by a recently developed proteomic approach. This is a pilot study of CSF proteomics for MMD using SELDI technology. These biomarker candidates have the potential to shed light on the underlying pathogenesis of MMD.
    BMC Neurology 11/2010; 10:112. · 2.17 Impact Factor
  • Article: Retrovirally engineered T-cell-based immunotherapy targeting type III variant epidermal growth factor receptor, a glioma-associated antigen.
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    ABSTRACT: The isotype of epidermal growth factor receptor variant III (EGFRvIII) is often identified in glioblastomas. Previously, we created a mouse monoclonal antibody, 3C10 (IgG2b), that specifically recognized EGFRvIII, and a recombinant single-chain variable fragment of 3C10. The aim of the current study was to develop genetically engineered T cells, termed T-bodies, that express a chimeric receptor consisting of the 3C10 single-chain variable fragment coupled to signaling modules such as the CD3zeta (ζ) chain, for the treatment of tumors expressing mutant EGFR. After successful construction of the chimeric 3C10/CD3ζ T-cell receptor, its expression on the T-body was observed using western blotting and flow cytometry. The specificity of the T-body for EGFRvIII was evaluated using an interferon-gamma Elispot assay and a standard (51) Cr-release cytotoxicity assay. Furthermore, we demonstrated that the systemically delivered T-body infiltrated the intrabrain tumor and significantly delayed tumor growth. These results indicate that the T-body expressing the chimeric 3C10/CD3ζ T-cell receptor specifically recognized glioma cells expressing EGFRvIII. In conclusion, T-body-based immunotherapy appears to be a promising approach for the treatment of glioma.
    Cancer Science 09/2010; 101(12):2518-24. · 3.33 Impact Factor
  • Article: Low expression of microphthalmia-associated transcription factor, a potential molecular target for interferon-alpha susceptibility, is associated with metastasis in renal cell carcinoma.
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    ABSTRACT: We previously reported that microarray expression profiling identified several candidate genes in association with interferon-alpha (IFN-alpha) response in renal cell carcinoma (RCC) cell lines (Cancer Sci 2007; 98: 529). Among them, we focused on microphthalmia-associated transcription factor (MITF), because its expression profile correlated well with IFN-alpha-response status. In addition, we investigated the clinical significance of the expression level of MITF using surgical specimens. RNA was extracted from 14 RCC cell lines and 65 RCC samples and was used in this study. Transfection of MITF cDNA into IFN-alpha-resistant RCC cell lines resulted in elevation of MITF expression and acquisition of IFN-alpha-sensitivity by quantitative PCR and WST-8 assay, respectively. Statistical analysis revealed that low MITF mRNA expression in RCC samples was significantly correlated with the presence of metastasis and poor survival of the patient. However, the correlation between MITF expression and IFN-alpha response was not obvious in the clinical cases. MITF gene transfection elevated IFN-alpha-sensitivity in RCC cell lines, suggesting that this gene is a target molecule for modulation of the IFN-alpha response. Quantification of MITF mRNA expression might be clinically useful to predict metastasis and survival of patients with RCC.
    Cancer Science 06/2009; 100(9):1714-8. · 3.33 Impact Factor
  • Article: SCL/TAL1 interrupting locus derepresses GLI1 from the negative control of suppressor-of-fused in pancreatic cancer cell.
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    ABSTRACT: As a physically binding protein of GLI1 transcription factor, Suppressor-of-Fused (SUFU) has been placed in the center of negative regulation of Hedgehog (Hh) signaling. SUFU tethers GLI1 in cytoplasm, and in some circumstances, it moves into the nucleus in association with GLI1, leading to the suppression of GLI1 target gene expression by recruiting a corepressor complex. The activated transcriptional function of GLI1 is important for cellular proliferation in a variety of human cancers. However, it has not been revealed how GLI1 is derepressed from SUFU-mediated suppression. Here, we show SCL/TAL1 interrupting locus (SIL) product, a cytoplasmic protein overexpressed in pancreatic ductal adenocarcinoma (PDA), is responsible for the derepression of GLI1. We found SIL associated with the carboxyl terminus of SUFU, one of two distinct GLI1-binding domains, and this association was responsible for cytoplasmic tethering of SUFU. Overexpressed SIL attenuated SUFU-mediated cytoplasmic tethering and target gene suppression of GLI1. Knockdown of SIL in PDA cells conversely induced the nuclear accumulation of SUFU in association with GLI1 and the transcriptional suppression of GLI1 target genes. Importantly, we also showed that oncogenic K-RAS, and not Sonic hedgehog, enhanced the SIL association with the amino-terminus of SUFU, the other GLI1-binding domain that led to further increase of nuclear translocation of GLI1. These results uncover the role of SIL in derepressing GLI1 from the negative control of SUFU, which is a crucial step for activating Hh signaling in cancer cells.
    Cancer Research 11/2008; 68(19):7723-9. · 7.86 Impact Factor
  • Article: Combinations of tumor-specific CD8+ CTLs and anti-CD25 mAb provide improved immunotherapy.
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    ABSTRACT: One new approach to cancer therapy is based on the adoptive transfer of tumor-specific cytotoxic T cells and anti-CD25 antibodies. In the present study, CD8+ and IFN-gamma secreting T lymphocytes (CTLs) were enriched as tumor-specific cytotoxic T cells from spleen lymphocytes of mice bearing the Renca tumor (a murine renal carcinoma line originating from a BALB/c mouse) after stimulation with tumor cells. An anti-CD25 IL-2Ralpha(anti-CD25) mAb from hybridoma PC61 was used for depletion for CD4(+)CD25(+) regulatory T (Treg) cells. Treatment-efficacy for tumor-bearing mice was compared using 4 systems: 1, whole spleen lymphocytes stimulated with tumor cells in vitro from tumor-bearing mice; 2, CTLs; 3, anti-CD25 mAbs; 4, CTLs and anti-CD25 mAbs. At the 50th day after tumor inoculation, in the group which received anti-CD25 mAb for depletion of T cells and inoculation of CTLs, tumors had disappeared and no re-growth was observed. In contrast, all mice of the non-treated and other three groups, treated with whole spleen cells alone, CTLs alone and anti-CD25 mAb alone, had died. These results showed that a combination of Treg cell-depletion using anti-CD25 mAbs and CTL administration is a feasible approach for treatment of cancers which warrants further exploration in the clinical setting.
    Oncology Reports 06/2008; 19(5):1265-70. · 1.84 Impact Factor
  • Article: Potent synergy of dual antitumor peptides for growth suppression of human glioblastoma cell lines.
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    ABSTRACT: Molecular targeting agents have become formidable anticancer weapons, which show much promise against the refractory tumors. Functional peptides are among the more desirable of these nanobio-tools. Intracellular delivery of multiple functional peptides forms a basis for potent, non-invasive mode of delivery, providing distinctive therapeutic advantages. Here, we examine growth suppression efficiency of human glioblastomas by dual-peptide targeting. We did simultaneous introduction of two tumor suppressor peptides (p14(ARF) and p16(INK4a) or p16(INK4a) and p21(CIP1) functional peptides) compared with single-peptide introduction using Wr-T-mediated peptide delivery. Wr-T-mediated transport of both p14(ARF) and p16(INK4a) functional peptides (p14-1C and p16-MIS, respectively) into human glioblastoma cell line, U87DeltaEGFR, reversed specific loss of p14 and p16 function, thereby drastically inhibiting tumor growth by >95% within the first 72 h, whereas the growth inhibition was approximately 40% by p14 or p16 single-peptide introduction. Additionally, the combination of p16 and p21(CIP1) (p21-S154A) peptides dramatically suppressed the growth of glioblastoma line Gli36DeltaEGFR, which carries a missense mutation in p53, by >97% after 120 h. Significantly, our murine brain tumor model for dual-peptide delivery showed a substantial average survival enhancement (P < 0.0001) for peptide-treated mice. Wr-T-mediated dual molecular targeting using antitumor peptides is highly effective against growth of aggressive glioblastoma cells in comparison with single molecule targeting. Thus, jointly restoring multiple tumor suppressor functions by Wr-T-peptide delivery represents a powerful approach, with mechanistic implications for development of efficacious molecular targeting therapeutics against intractable human malignancies.
    Molecular Cancer Therapeutics 06/2008; 7(6):1461-71. · 5.23 Impact Factor
  • Article: Prediction of in vitro response to interferon-alpha in renal cell carcinoma cell lines.
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    ABSTRACT: We analyzed the correlation between interferon-alpha (IFNalpha) response and gene expression profiles to predict IFNalpha sensitivity and identified key molecules regulating the IFNalpha response in renal cell carcinoma (RCC) cell lines. To classify eight RCC cell lines of the SKRC series into three subgroups according to IFNalpha sensitivity, that is, sensitive, resistant and intermediate group, responses to IFNalpha (300-3000 IU/mL) were quantified by WST-1 assay. Microarray, followed by supervised hierarchical clustering analysis, was applied to selected genes according to IFNalpha sensitivity. In order to find alteration of expression profiles induced by IFNalpha, sequential microarray analyses were performed at 3, 6, and 12 h after IFNalpha treatment of RCC cell lines and mRNA expression level was confirmed using quantitative real time polymerase chain reaction. According to the sequential microarray analysis between IFNalpha-sensitive and -resistant line, seven genes were selected as candidates for IFNalpha-sensitivity-related genes in RCC cell lines. Among these seven genes, we further developed a model to predict tumor inhibition with four genes, that is, adipose differentiation-related protein, microphthalmia associated transcription factor, mitochondrial tumor suppressor 1, and troponin T1 using multiple linear regression analysis (coefficient=0.948, P=0.0291) and validated the model using other RCC cell lines including six primary cultured RCC cells. The expression levels of the combined selected genes may provide predictive information on the IFNalpha response in RCC. Furthermore, the IFNalpha response to RCC might be modulated by regulation of the expression level of these molecules.
    Cancer Science 05/2007; 98(4):529-34. · 3.33 Impact Factor
  • Article: Differential profiling analysis of proteins involved in anti-proliferative effect of interferon-alpha on renal cell carcinoma cell lines by protein biochip technology.
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    ABSTRACT: Interferon-alpha (IFN) is widely used for the treatment of progressive renal cell carcinoma (RCC), but its effective response rate is only about 15%. New biomarkers of RCC contributing to the effective IFN treatment are needed to establish a sensitivity test for evaluating if the IFN is effective or not against RCC. All the proteins expressed in the IFN-susceptible and -resistant RCC cell lysates were analyzed by surface enhanced laser desorption ionization (SELDI) mass spectrometry using ProteinChip technology and their different protein expression were detected by the comparison of the profiles between them. We detected the following candidate markers that exhibited peak shifts: a) in the IFN-susceptible cell lines, a candidate marker with a molecular weight of 5,688 Da was detected on a hydrophobic (H4) chip: b) in the IFN-resistant cell lines, candidate markers each with a molecular weight of 8,049, 3,157, 3,993, and 8,959 Da were detected on strong anion exchange (SAX2, pH 9.0, two types) chips, H4 chip, and weak cation exchange (WCX, pH 9.0) chips, respectively. IFN treatment produced no weight increase in these four proteins, and c) candidate marker with a molecular weight of 1,623 Da that was expressed in both cell lines after the IFN treatment was detected on the H4 chip. These data suggest that the ProteinChip system is very useful in identifying proteins showing unique peaks in the RCC cell lines with different IFN susceptibility, and the comparison of these proteins measured in RCC cell lysates may help to identify the IFN sensitivity. Furthermore, the discovery of a susceptibility and or a inhibitory factor may eventually lead to the development of a novel drug targeting the respective factor for the improvement of anticancer chemotherapy.
    International Journal of Oncology 05/2006; 28(4):965-70. · 2.40 Impact Factor
  • Article: A phase I trial of vaccination of CA9-derived peptides for HLA-A24-positive patients with cytokine-refractory metastatic renal cell carcinoma.
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    ABSTRACT: A phase I peptide vaccination trial was done in patients with progressive cytokine-refractory metastatic renal cell carcinoma (RCC) to assess both the toxicity and capability to induce immune responses of three peptides (CA9p219-227, p288-296, and p323-331) derived from CA9, a tumor-associated antigen ubiquitously expressed in RCC. Twenty-three patients positive for human leukocyte antigen (HLA)-A24 with histologically confirmed RCC were enrolled. Eligibility included progressive disease after standard cytokine therapy with interleukin-2 and/or IFN-alpha. Patients were vaccinated s.c. with the three peptides emulsified in incomplete Freund's adjuvant at 2-week intervals. Pre- and post-vaccination blood samples were obtained for toxicity assessment and immunologic studies. Patients were monitored for clinical responses on a 3-monthly basis. Vaccinations were well tolerated without any major adverse event. Most of the patients developed peptide-specific CTLs and/or immunoglobulin G reactive to the peptides after the 6th or 9th vaccination, followed by a gradual increase in both CTL frequency and levels of peptide-reactive serum IgG. Three patients with multiple lung metastases showed partial responses with disappearance and shrinking of metastatic lesions. Additionally, stable disease for >6 months was observed in six patients (median duration, 12.2 months). Moreover, the median survival time of all patients who were progressive at trial enrollment after failing immunotherapy was 21.0 months (5-35 months). These results suggest that vaccination of these peptides is safe and recommended for further trials for HLA-A24-positive metastatic RCC patients.
    Clinical Cancer Research 03/2006; 12(6):1768-75. · 7.74 Impact Factor
  • Article: Multiple endocrine neoplasia type I and Cushing's syndrome due to an aggressive ACTH producing thymic carcinoid.
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    ABSTRACT: Thymic carcinoid in multiple endocrine neoplasia type 1 (MEN 1) is previously reported as a non-ACTH producing tumor. The present case is a 39-year-old man with mortal outcome from thymic carcinoid and Cushing's syndrome with high plasma ACTH. The symptom was first observed at age 29 and was relieved after extended thymectomy, with reduction of ACTH level. The tumor was positive for ACTH, Grimelius silver staining and Chromogranin A. The finding of primary hyperparathyroidism, pituitary adenoma, and a novel germline nonsense mutation (W423X) established the diagnosis of MEN 1. Cushing's syndrome due to ACTH producing thymic carcinoid should be also considered as one phenotype of the MEN 1 spectrum.
    Internal Medicine 02/2006; 45(2):81-6. · 0.94 Impact Factor
  • Article: [Antibody-based therapy for brain tumor].
    Syuntaro Takasu, Kazuhiro Yoshikawa, Jun Yoshida
    Nippon rinsho. Japanese journal of clinical medicine 10/2005; 63 Suppl 9:563-8.
  • Article: Targeting Hyperthermia for Renal Cell Carcinoma Using Human MN Antigenspecific Magnetoliposomes
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    ABSTRACT: Magnetoliposomes (MLs) conjugated with an antibody fragment to give specificity to a tumor were applied to hyperthermia for cancer. The Fab' fragment of the G250 antibody, which binds to MN antigen on many types of human renal cell carcinoma, was cross–linked to Af–(6–maleimidocaproyl–oxy)–dipalmitoyl phosphatidylethanolamine (EMC–DPPE) in liposomal membrane. The targetabil–ity of the G250–Fab' fragment–conjugating MLs (G250–FMLs) was investigated using the mouse renal cell carcinoma (mRCC) and MN antigen–presenting cell, MN–mRCC. The amount of G250–FMLs uptake reached 67 pg/cell against MN–mRCC cells in an in vitro experiment using plastic dishes and this value was about 6 tunes higher than that in the case of MLs. In an in vivo experiment using MN–mRCC–harboring mice, 1.5 mg of the FMLs per carcinoma tissue accumulated (tumor weight was 0.19 g), which corresponded to approximately 50% of the total injection. This value was 27 tunes higher than that of the MLs. After injection of the FMLs, mice were exposed to intracellular hyperthermia using alternating magnetic field irradiation. The temperature of tumor tissue increased to 43°C and the growth of the carcinoma was strongly arrested for at least 2 weeks. These results indicate the G250–FMLs could target renal cell carcinoma cells in vitro and in vivo, and are efficiently applicable to the hyper thermic treatment of carcinoma.
    Cancer Science 08/2005; 92(10):1138 - 1146. · 3.33 Impact Factor
  • Article: Production and characterization of an active single-chain variable fragment antibody recognizing CD25.
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    ABSTRACT: The alpha subunit of the interleukin-2 receptor (IL-2Ralpha, CD25) is a potential target in therapeutic approaches for hematolopoietic malignancies expressing CD25 on their cell surface, such as adult T cell leukemia/lymphomas. Recent reports have demonstrated that depletion of CD4+CD25+ regulatory T cells with anti-CD25 antibodies may enhance host tumor immunity. We previously raised a mouse monoclonal antibody (mAb), Ta60b mAb (IgG1kappa), specifically recognizing CD25, and an attempt was made here to produce a single chain Fv fragment (scFv) from this mAb as an initial step to development of scFv-based therapeutics. cDNA fragments encoding for the variable regions of the light and heavy chains of the Ta60b mAb were thus isolated by polymerase chain reaction-mediated cloning, and, an expression vector constructed to express Ta60b scFv fused with the maltose binding protein (MBP) in the periplasm of Escherichia coli. The soluble form of MBP-Ta60b fused scFv could be extracted and affinity-purified with an amylose/agarose column, allowing its immunoreactivity to be analyzed by enzyme-linked immunosorbent assay (ELISA), mixed hemadsorption assay, and fluorescence activated cell sorting. In addition, binding activity was studied by competitive ELISA and surface plasmon resonance. The results showed that Ta60b scFv obtained from periplasm retains good reactivity, although its KD value was 4-fold lower than that of the whole Ta60b antibody, suggesting possible clinical use for treatment of patients with CD25-expressing tumors and also for enhancing anti-tumor immunity.
    Cancer Letters 08/2005; 225(2):225-36. · 4.24 Impact Factor
  • Article: Highly efficient delivery of p16 antitumor peptide into aggressive leukemia/lymphoma cells using a novel transporter system.
    Eisaku Kondo, Masao Seto, Kazuhiro Yoshikawa, Tadashi Yoshino
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    ABSTRACT: Molecular targeting of hematopoietic malignancies has been generally hindered by technological obstacles to gene delivery in the neoplastic cells. The development of peptide delivery systems based on protein transduction domains has recently gained attention as a means of potentially overcoming these impediments. Here, we present a novel peptide transporter system that increases the efficiency of peptide delivery more than 10 times compared with the previous methods. The transporter, Wr-T, has an enlarged hydrophobic pocket consisting of triple tryptophan-rich domains fused with nine d-enantiomer polyarginines (r9) via Gly-Pro-Gly spacer, which serves to augment delivery of a cargo peptide. Wr-T-mediated transport of p16(INK4a) functional peptide dramatically inhibits growth of highly aggressive leukemia/lymphomas by up to 80% through restoration of p16 function. The Wr-T system thus represents a highly effective approach to cargo peptide delivery with the potential for substantially developing p16 peptide-based therapy for hematopoietic malignancies.
    Molecular Cancer Therapeutics 01/2005; 3(12):1623-30. · 5.23 Impact Factor
  • Article: The level of cadherin-6 mRNA in peripheral blood is associated with the site of metastasis and with the subsequent occurrence of metastases in renal cell carcinoma.
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    ABSTRACT: To evaluate the significance of the presence of circulating renal cell carcinoma (RCC) cells in the development of metastases, the authors extended a previous study to quantify cadherin-6 mRNA levels in association with the pattern of metastasis. Cadherin-6 mRNA levels were measured in peripheral blood samples from 66 patients with RCC, including 55 patients who had newly diagnosed RCC (43 without metastases and 12 with metastases) and 11 patients who had recurrent RCC. For quantitative polymerase chain reaction analysis, a cutoff value was determined in blood samples from 25 healthy volunteers and was verified in samples from 5 healthy controls and from 10 patients who had other malignancies. The correlation between the site of metastases and the cadherin-6 mRNA level was analyzed, and a follow-up study (median, 39 months) to track subsequent metastases was performed after patients underwent nephrectomy. Cadherin-6 was found in 69.9% of patients with metastases and in 34.9% of patients without apparent metastases (P = 0.0099). In the group of patients with recurrent RCC, patients who had only pulmonary metastases had a significantly lower positivity rate (25.0%) compared with patients who had distant metastases (85.7%; P = 0.044). Among 43 patients with newly diagnosed RCC, 5 of 15 patients who were positive for cadherin-6 had metastases after nephrectomy, whereas only 2 of the 28 patients with negative cadherin-6 status had recurrent disease (P = 0.0398). In addition, the recurrence-free survival of patients who were positive for cadherin-6 was poorer compared with the survival of patients who were negative for cadherin-6 (P = 0.062). The quantification of cadherin-6 mRNA in peripheral blood may be a significant predictive marker for current and future metastases. However, subsequent metastases did not always correlate with levels of cadherin-6 mRNA. This may have been due either to the small numbers of circulating tumor cells or to the low levels cadherin-6 mRNA in circulating tumor cells.
    Cancer 10/2004; 101(5):963-8. · 4.77 Impact Factor
  • Article: Detection of cadherin-6 mRNA by nested RT-PCR as a potential marker for circulating cancer cells in renal cell carcinoma.
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    ABSTRACT: To detect circulating RCC cells, we established a nested RT-PCR system for cadherin-6 mRNA, which is specifically expressed in RCC. A total of 121 samples of peripheral blood (34 healthy volunteers and 87 patients with RCC) were analyzed in this study. Total RNA of the monocyte fraction of the blood was extracted, then nested RT-PCR using specific primers was performed to detect mRNA of N-cadherin or cadherin-6. Nested RT-PCR revealed that expression of cadherin-6 mRNA was not present in the blood of most healthy volunteers (absent in 32/34), but positive expression was observed in the blood at concentrations of 10 cells/ml or greater of the SKRC-33 RCC cell line, which is a strong expresser of cadherin-6. In peripheral blood from patients with metastatic disease, cadherin-6 mRNA was detected in 70.4% (19/27). Messenger RNA of cadherin-6 was detectable in 45.0% (27/60) of patients with localized tumors. The PCR-based detection system for peripheral blood samples from patients with metastatic disease could reveal the presence of circulating RCC cells in the blood. Detection of cadherin-6 mRNA in non-metastatic presurgical RCC patients suggests that careful follow-up study is necessary in these patients.
    International Journal of Oncology 11/2003; 23(4):1049-54. · 2.40 Impact Factor