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Manabu Kawakami

Publications and source records attributed to Manabu Kawakami.

At least 19 recordsLinked to original sources
PubMed2006

A phase I/II trial of a WT1 (Wilms' tumor gene) peptide vaccine in patients with solid malignancy: safety assessment based on the phase I data.

OBJECTIVE: We conducted a phase I study to investigate the safety of a weekly WT1 tumor vaccine therapy in patients with solid tumors that had been refractory to all other anti-cancer therapies. METHODS: Skin-test-negative patients were intradermally injected weekly for 12 weeks with 3.0 mg of an HLA-A*2402-restricted modified 9-mer WT1 peptide emulsified in Montanide ISA51 adjuvant. We estimated the Bayesian posterior probability of the occurrence of grade 3 or 4 toxicity when receiving the weekly WT1 vaccination. This analysis provided the basis for making a decision to terminate the phase I study and switch to phase II. Moreover, we performed an exploratory assessment of the anti-tumor effects of WT1 treatment. RESULTS: Ten patients received 114 vaccinations with WT1 on a weekly schedule. No grade 3 or 4 toxicities were observed. Based on the Bayesian approach, it was highly likely that the probability of grade 3 or 4 toxicity was below 20% (the posterior probability = 0.914). Fifteen grade 2 and two grade 1 toxicities were observed; all of these incidents, however, were determined by the Independent Data and Safety Monitoring Committee to be unrelated to the WT1 treatment. One patient exhibited a partial response; five additional patients had stable disease while receiving weekly WT1 treatment. CONCLUSION: This paper confirms that the potential toxicities of the treatment schedule of weekly WT1 vaccination are acceptable and suggested a potential anti-tumor effect. Consequently, we validated the decision to continue to the phase II trial.

Adolescent↗
PubMed2006

Unmanipulated HLA 2-3 antigen-mismatched (haploidentical) stem cell transplantation using nonmyeloablative conditioning.

The major problems in human leukocyte antigen (HLA)-mismatched stem cell transplantation (SCT) are graft failure and graft-versus-host disease (GVHD). Less-intensive regimens should be associated with a lower release of inflammatory cytokines and possibly less GVHD. The objective of this study was to investigate whether HLA-haploidentical SCT can be performed using nonmyeloablative conditioning and pharmacologic GVHD prophylaxis, including glucocorticoids. Using conditioning consisting of fludarabine, busulfan, and anti-T-lymphocyte globulin and GVHD prophylaxis consisting of tacrolimus and methylprednisolone (1 mg/kg/day), 26 patients who had hematologic malignancies in an advanced stage or with a poor prognosis underwent transplantation using peripheral blood stem cells from an HLA-haploidentical donor (2-3 antigen mismatches in the graft-versus-host [GVH] direction) without T-cell depletion. All patients except for 1 achieved donor-type engraftment. Rapid hematologic engraftment was achieved (neutrophils > 0.5 x 10(9)/L on day 12 and platelets > 20 x 10(9)/L on day 12), with full donor chimerism achieved by day 14. Fifteen patients did not develop acute GVHD clinically, and only 5 patients developed grade II GVHD. The recovery of CD4+ T cells was delayed compared with that of CD8+ T cells. Sixteen of the 26 patients are alive in complete remission. Four died of transplantation-related causes, and 6 died of progressive disease. These data suggest that nonmyeloablative conditioning, GVHD prophylaxis consisting of tacrolimus and methylprednisolone, and early therapeutic intervention for the GVH reaction allow stable engraftment and effectively suppress GVHD in HLA 2-3 antigen-mismatched SCT.

Adult↗
PubMed2006

Wilms' tumor gene WT1 17AA(-)/KTS(-) isoform induces morphological changes and promotes cell migration and invasion in vitro.

The wild-type Wilms' tumor gene WT1 is overexpressed in human primary leukemia and in a wide variety of solid cancers. All of the four WT1 isoforms are expressed in primary cancers and each is considered to have a different function. However, the functions of each of the WT1 isoforms in cancer cells remain unclear. The present study demonstrated that constitutive expression of the WT1 17AA(-)/KTS(-) isoform induces morphological changes characterized by a small-sized cell shape in TYK-nu.CP-r (TYK) ovarian cancer cells. In the WT1 17AA(-)/KTS(-) isoform-transduced TYK cells, cell-substratum adhesion was suppressed, and cell migration and in vitro invasion were enhanced compared to that in mock vector-transduced TYK cells. Constitutive expression of the WT1 17AA(-)/KTS(-) isoform also induced morphological changes in five (one gastric, one esophageal, two breast and one fibrosarcoma) of eight cancer cell lines examined. No WT1 isoforms other than the WT1 17AA(-)/KTS(-) isoform induced the phenotypic changes. A decrease in alpha-actinin 1 and cofilin expression and an increase in gelsolin expression were observed in WT1 17AA(-)/KTS(-) isoform-transduced TYK cells. In contrast, co-expression of alpha-actinin 1 and cofilin or knockdown of gelsolin expression by small interfering RNA restored WT1 17AA(-)/KTS(-) isoform-transduced TYK cells to a phenotype that was comparable to that of the parent TYK cells. These results indicated that the WT1 17AA(-)/KTS(-) isoform exerted its oncogenic functions through modulation of cytoskeletal dynamics. The present results may provide a novel insight into the signaling pathway of the WT1 gene for its oncogenic functions.

Actinin↗
PubMed2005

AML1-ETO rapidly induces acute myeloblastic leukemia in cooperation with the Wilms tumor gene, WT1.

AML1-ETO, a chimeric gene frequently detected in acute myelogenous leukemia (AML), inhibits the differentiation of myeloid progenitors by suppressing genes associated with myeloid differentiation and increases the replating ability of clonogenic myeloid progenitors. However, AML1-ETO alone cannot induce AML and thus additional genetic events are required for the onset of AML. The Wilms tumor gene (WT1), which has been identified as the gene responsible for Wilms tumor, is expressed at high levels in almost all human leukemias. In this study, we have generated transgenic mice (WT1-Tg) that overexpress WT1 in hematopoietic cells to investigate the effects of WT1 on AML1-ETO-associated leukemogenesis. AML1-ETO-transduced bone marrow (BM) cells from WT1-Tg mice exhibited inhibition of myeloid differentiation at more immature stages and higher in vitro colony-forming ability compared with AML1-ETO-transduced BM cells from wild-type mice. Most importantly, all of the mice that received a transplant of AML1-ETO-transduced BM cells from the WT1-Tg mice rapidly developed AML. These results demonstrate that AML1-ETO may exert its leukemogenic function in cooperation with the expression of WT1.

Animals↗
PubMed2005

The Wilms' tumor gene WT1 is a common marker of progenitor cells in fetal liver.

It is well known that the Wilms' tumor gene WT1 plays an important role in cell proliferation and differentiation, and in organ development. In this study, to examine the role of the WT1 gene in lineage determination, fetal liver cells from LacZ-transgenic mice, in which WT1 expression was marked by the expression of the LacZ gene driven by WT1 promoter, were FACS-sorted according to LacZ expression of high (LacZ(++)) or undetectable (LacZ(-)) levels, which paralleled endogenous WT1 expression levels. LacZ(++) fetal liver cells were enriched by hepatocyte and endothelial progenitor cells. These results indicated that WT1 expression is a common marker of both hepatocyte and endothelial progenitors. These results also implied a role of the WT1 gene in lineage determination.

Animals↗
PubMed2005

A case of immune recovery vitritis induced by donor leukocyte infusion for the treatment of cytomegalovirus retinitis.

Donor leukocyte infusion (DLI) has been successfully used for some life-threatening viral infections after stem cell transplantation (SCT). We describe here the first case of DLI treatment for cytomegalovirus (CMV) retinitis. A 49-year-old female patient with AML, M1 underwent SCT with a reduced-intensity conditioning regimen from HLA-haploidentical son. On day +140, the patient developed CMV retinitis of her left eye despite the continuing antiviral therapy. DLI at a dose of 1 x 10(5) CD3+ cells/kg was added to ganciclovir and foscarnet therapy. Eighteen days after the DLI, the funduscopic findings revealed improvement of the retinitis and the development of vitreous inflammation. Simultaneously, the number of CD4+ cells in the peripheral blood rapidly increased. Thus, we consider it likely that DLI induced a local immune response against CMV antigens, which resulted in the immune recovery vitritis. This case suggested the potentiality of DLI for the treatment of CMV retinitis.

Acute Disease↗
PubMed2004

Induction of WT1 (Wilms' tumor gene)-specific cytotoxic T lymphocytes by WT1 peptide vaccine and the resultant cancer regression.

The Wilms' tumor gene WT1 is overexpressed in leukemias and various types of solid tumors, and the WT1 protein was demonstrated to be an attractive target antigen for immunotherapy against these malignancies. Here, we report the outcome of a phase I clinical study of WT1 peptide-based immunotherapy for patients with breast or lung cancer, myelodysplastic syndrome, or acute myeloid leukemia. Patients were intradermally injected with an HLA-A*2402-restricted, natural, or modified 9-mer WT1 peptide emulsified with Montanide ISA51 adjuvant at 0.3, 1.0, or 3.0 mg per body at 2-week intervals, with toxicity and clinical and immunological responses as the principal endpoints. Twenty-six patients received one or more WT1 vaccinations, and 18 of the 26 patients completed WT1 vaccination protocol with three or more injections of WT1 peptides. Toxicity consisted only of local erythema at the WT1 vaccine injection sites in patients with breast or lung cancer or acute myeloid leukemia with adequate normal hematopoiesis, whereas severe leukocytopenia occurred in patients with myelodysplastic syndrome with abnormal hematopoiesis derived from WT1-expressing, transformed hematopoietic stem cells. Twelve of the 20 patients for whom the efficacy of WT1 vaccination could be assessed showed clinical responses such as reduction in leukemic blast cells or tumor sizes and/or tumor markers. A clear correlation was observed between an increase in the frequencies of WT1-specific cytotoxic T lymphocytes after WT1 vaccination and clinical responses. It was therefore demonstrated that WT1 vaccination could induce WT1-specific cytotoxic T lymphocytes and result in cancer regression without damage to normal tissues.

Amino Acid Substitution↗
PubMed2004

Successful treatment of life-threatening human herpesvirus-6 encephalitis with donor lymphocyte infusion in a patient who had undergone human leukocyte antigen-haploidentical nonmyeloablative stem cell transplantation.

BACKGROUND: Encephalitis as the result of human herpesvirus (HHV)-6 is usually fatal when it is resistant to antiviral drugs. METHODS: We describe a patient who developed HHV-6 encephalitis after human leukocyte antigen-haploidentical transplantation using a reduced intensity regimen. RESULTS: The patient developed severe disorientation, amnesia, and tremors on day 28. Magnetic resonance imaging of the brain revealed limbic encephalitis, and the cerebrospinal fluid sample was positive for only HHV-6 in polymerase chain reaction analysis. Neither ganciclovir nor foscarnet was effective. The patient recovered from the critical condition of HHV-6 encephalitis after donor lymphocyte infusion (DLI). Almost all of his symptoms resolved, polymerase chain reaction tests for HHV-6 in the cerebrospinal fluid were negative, and magnetic resonance imaging findings were normal. CONCLUSIONS: This is the first report of DLI as a treatment for HHV-6 encephalitis and the first report of DLI from an human leukocyte antigen-haploidentical donor as a treatment for life-threatening viral infection.

Adult↗
PubMed2004

WT1 peptide vaccination combined with BCG-CWS is more efficient for tumor eradication than WT1 peptide vaccination alone.

A Wilms' tumor gene WT1 is expressed at high levels not only in most types of leukemia but also in various types of solid tumors, including lung and breast cancer. WT1 protein has been reported to serve as a target antigen for tumor-specific immunotherapy both in vitro in human systems and in vivo in murine models. We have shown that mice immunized with WT1 peptide or WT1 cDNA could reject a challenge from WT1-expressing tumor cells (a "prophylactic" model). However, it was not examined whether WT1 peptide vaccination had the potency to reject tumor cells in a "therapeutic" setting. In the present study, we demonstrated for the first time that WT1 peptide vaccination combined with Mycobacterium bovis bacillus Calmette-Guérin cell wall skeleton (BCG-CWS) was more effective for eradication of WT1-expressing tumor cells that had been implanted into mice before vaccination (a "therapeutic" model) compared with WT1 peptide vaccination alone. An intradermal injection of BCG-CWS into mice, followed by that of WT1 peptide at the same site on the next day, generated WT1-specific cytotoxic T lymphocytes (CTLs) and led to rejection of WT1-expressing leukemia or lung cancer cells. These results showed that BCG-CWS, which was well known to enhance innate immunity, could enhance WT1-specific immune responses (acquired immunity) in combination with WT1 peptide vaccination. Therefore, WT1 peptide vaccination combined with BCG-CWS may be applied to cancer immunotherapy in clinical settings.

Animals↗
PubMed2004

Effect of heparin addition on expansion of cord blood hematopoietic progenitor cells in three-dimensional coculture with stromal cells in nonwoven fabrics.

Primary human cord blood mononuclear cells (CB MNCs) were inoculated into layers of primary human bone marrow stromal cells prepared in a nonwoven fabric porous carrier [three dimensional (3-D)] or on a dish [two dimensional (2-D)] using a cytokine-free medium and were cultured for 7 days with or without the addition of heparin. The number of progenitor cells increased threefold during the 3-D coculture, whereas it decreased in the 2-D culture. Heparin addition to the 3-D coculture further increased the number of progenitors twofold, whereas the addition of desulfated heparin had no effect. The heparin effect was also observed in a 3-D culture of CB MNCs without stromal cells when conditioned medium was employed. The coating of the carrier with N-(O-beta-(6-O-sulfogalactopyranosyl)-6-oxyhexyl)-3,5-bis (dodecyloxy)-benzamide instead of heparin addition also increased the number of progenitor cells in the 3-D culture of CB MNCs without stromal cells when the conditioned medium was employed. The 3-D coculture constructed with nonwoven fabrics and stromal cells was clearly superior to the 2-D culture because of the expansion of CB hematopoietic progenitor cells without cytokine addition. Heparin addition to the 3-D coculture further increased the number of progenitor cells, which may result from a synergistic effect of soluble cytokines produced by stromal cells with the sulfur group of heparin.

Animals↗
PubMed2004

Solitary right ventricle metastasis by renal cell carcinoma.

A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography.

Carcinoma, Renal Cell↗
PubMed2004

WT1 gene transcript assay for relapse in acute leukemia after transplantation.

The WT1 gene is highly expressed in various types of leukemia, particularly in acute type leukemia. The extent of minimal residual disease (MRD) of leukemia can be evaluated by measuring the WT1 gene expression level using a quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method. The WT1 transcript assay can be applied to almost all patients with leukemia regardless of the presence or absence of chimeric DNA markers. Furthermore, because of the fact that WT1 expression levels increase significantly at relapse compared with those at the time of diagnosis, and because of the decrease in background levels of WT1 expression in bone marrow following allogeneic SCT, the WT1 transcript assay possesses a high degree of sensitivity following allogeneic SCT. Frequent monitoring of the WT1 gene expression level predicts the risk of relapse following allogeneic SCT, and furthermore, the kinetics of WT1 transcripts predict the efficacy of immunomodulation therapy such as donor leukocyte infusion.

Acute Disease↗
PubMed2004

Absence of mutations in the Wilms' tumor gene WT1 in primary breast cancer.

BACKGROUND: It was recently demonstrated that the WT1 gene was overexpressed in primary breast cancer and that the high expression levels of WT1 mRNA significantly correlated with poor prognosis. However, it remained undetermined whether or not the WT1 gene expressed in breast cancer had mutations. METHODS: Breast cancer tissues were obtained from 36 patients with breast cancer. WT1 genomic DNA was PCR-amplified and examined for mutations by direct sequencing. RESULTS: The sequencing analysis showed the absence of mutations through the whole 10 exons of the WT1 gene in the 36 cases of primary breast cancer. Two different single nucleotide polymorphisms (SNP) without an amino acid change (Pro42, C to T in exon 1, and/or Arg300, A to G in exon 7) were detected in the WT1 gene in 31 (86%) of the 36 cases examined. CONCLUSION: The results indicate that the wild-type WT1 gene plays an important role in the tumorigenesis of primary breast cancer.

Adult↗
PubMed2004

WT1 peptide-based immunotherapy for patients with lung cancer: report of two cases.

The Wilms' tumor gene WT1 is overexpressed in various types of solid tumors, including lung and breast cancer and WT1 protein is a tumor antigen for these malignancies. In phase I clinical trials of WT1 peptide-based cancer immunotherapy, two patients with advanced lung cancer were intradermally injected with 0.3 mg of an HLA-A*2402-restricted, 9-mer WT1 peptide emulsified with Montanide ISA51 adjuvant. Consecutive WT1 vaccination at 2-week intervals resulted in a reduction in tumor markers such as chorio-embryonic antigen (CEA) and sialyl Lewis (x) (SLX) and by a transient decrease in tumor size. No adverse effects except for local erythema at the injection sites of WT1 vaccine were observed. These results provided us with the first clinical evidence demonstrating that WT1 peptide-based immunotherapy should be a promising treatment for patients with lung cancer.

Aged↗
PubMed2004

Overexpression of the Wilms' tumor gene W T1 in primary astrocytic tumors.

Expression of the Wilms' tumor gene W T1 in primary astrocytic tumors was examined using a quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) or immunohistochemistry. Real-time RT-PCR showed that W T1 mRNA was expressed at various levels in all of the 25 astrocytic tumors examined. Immunohistochemical analysis showed that W T1 protein was expressed in 5 of 6 low-grade astrocytic tumors (grade I-II) and all of 18 high-grade ones (grade III-IV), and that expression levels of W T1 protein in high-grade tumors were significantly higher than those in low-grade ones. W T1 protein was not detected in the normal glial cells contained in the tumor specimens. Furthermore, treatment with W T1 antisense oligomers specifically inhibited growth of glioblastoma cell lines, U87-MG, A172, and T-98G. These results may indicate that the W T1 gene plays an important role in tumorigenesis of primary astrocytic tumors.

Adolescent↗