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Tomoki Naoe

Publications and source records attributed to Tomoki Naoe.

At least 55 records · Page 3Linked to original sources
PubMed2005

Long-term outcomes for unselected patients with acute myeloid leukemia categorized according to the World Health Organization classification: a single-center experience.

The actual utility of a new classification system of acute myeloid leukemia (AML) recently introduced by the World Health Organization (WHO) has not been thoroughly investigated yet. In this study, we evaluated long-term outcomes of unselected AML patients categorized according to the new WHO classification. Between 1990 and 2002, 109 adult AML cases were referred to our hospital. For the entire population, the median survival duration was 1.2 yr with a 5-yr survival rate of 31%. AML with recurrent genetic abnormalities accounted for 26%, AML with multilineage dysplasia for 29%, therapy-related AML for 13%, and AML not otherwise categorized for 32% of classifiable cases. Among the four groups, a significant difference was observed in terms of overall survival (P < 0.0001). Univariate analysis showed that six variables affected survival: cytogenetic risk, age, multilineage dysplasia, prior chemo/radiotherapy, type of treatment (intensive or palliative), and transplantation. However, in multivariate analysis no adverse prognostic impact of multilineage dysplasia and prior chemo/radiotherapy was detected (P = 0.4979 and 0.8702), whereas cytogenetic risk and patient age maintained their prognostic value (P = 0.0005 and 0.0100). These results indicate that outcomes for AML patients appear to be distinguished on the basis of the WHO classification, but the prognostic significance of multilineage dysplasia and prior therapy is lost after adjusting for cytogenetic risk and age. Our findings suggest that the WHO classification may be strengthened by greater emphasis on genetic/cytogenetic information.

Adolescent↗
PubMed2005

CD56/NCAM-positive Langerhans cell sarcoma: a clinicopathologic study of 4 cases.

This report concerns the clinicopathologic features of 4 patients with CD56/neural cell adhesion molecule (NCAM)-positive Langerhans cell sarcoma (LCS). Three of the patients were elderly, between 59 and 62 years of age at presentation, and the other was 35 years old. The presenting symptoms included fever, bone pain, and weakness. The patients shared some clinical findings, such as multiorgan involvement of lymph nodes, skin, lung, bone marrow, and spleen. LCS carries a poor prognosis, and 3 of the patients died of the disease within several years of presentation despite multiagent chemotherapy and radiotherapy. Of special interest is that all of the cases showed CD56 expression on the tumor cells in addition to expression of CD1a, S100beta, and langerin, the presence of which suggests derivation from Langerhans cells. For control, CD56 was also examined in 8 cases of Langerhans cell histiocytosis (LCH), a single-system unifocal or multifocal disease, and the results of staining of the tumor cells were negative. Our findings indicated that CD56 may be a clinically relevant biologic marker for predicting an intractable course of Langerhans cell neoplasms, although it is often difficult to draw a definite morphologically-based distinction between LCS and LCH.

Adult↗
PubMed2005

Assessment of the international prognostic scoring system for determining chemotherapeutic indications in myelodysplastic syndrome: Japanese retrospective multicenter study.

To standardize a rational therapeutic strategy of chemotherapy using the International Prognostic Scoring System (IPSS), we retrospectively analyzed 292 high-risk myelodysplastic syndrome (MDS) patients in 20 hospitals in Japan. Results of multivariate analysis of the data on patients who received all types of chemotherapy indicated that poor cytogenetics as shown by the IPSS was the only significant risk factor (P = .047). We then focused on the IPSS composition of each patient. The intermediate 2 (Int-2) category consisted of a heterogeneous group. We attempted to subdivide the category into Int-2A and Int-2B. Patients with good or intermediate cytogenetics had > or = 5% bone marrow (BM) blasts (Int-2A), and most of the other patients had poor cytogenetics and < or = 10% BM blasts (Int-2B). In the Int-2B category, overall survival for patients who received chemotherapy was significantly worse than for those who did not receive chemotherapy (P = .005). Most patients in the High category who had the diagnosis of MDS according to the World Health Organization classification had poor overall survival with or without chemotherapy. We propose the Int-2B and High categories may be considered possible high risk, whereas all patients in the Int-2A category and patients with more than 5% BM blasts in the Int-1 category may be categorized as being at possible intermediate risk. Our proposition may be useful for developing a chemotherapeutic strategy for patients with MDS in Japan.

Adult↗
PubMed2005

BMI-1 is highly expressed in M0-subtype acute myeloid leukemia.

Recent studies have suggested that one of the polycomb group genes, BMI-1, has an important role in the maintenance of normal and leukemic stem cells by repressing the INK4a/ARF locus. Here, we quantitatively examined BMI-1 expression level in samples from patients with acute myeloid leukemia (AML) and other hematologic malignancies. Moderate to high BMI-1 expression was detected in AML patients, and the BMI-1 expression levels in AML samples were significantly higher than in normal bone marrow controls (P = .0011). Specimens of French-American-British classification subtype M0 showed higher relative expression of the BMI-1 transcript (median, 390.2 3 10(-3)) than the other subtypes (median, 139.0 3 10(-3)) (P < .0001). Leukemia other than AML showed low to moderate expression. INK4a-ARF transcript expression tended to be inverse proportion to that of BMI-1. In an M0 patient with a high BMI-1 transcript level, the INK4a-ARF transcript level fell promptly and maintained a low value after the patient achieved complete remission. These results indicated that a subgroup of M0 patients has a high expression level of polycomb group gene BMI-1, which may contribute to leukemogenesis.

Acute Disease↗
PubMed2005

[Clinical course of the disease and the level of WT1 mRNA in 191 patients with acute myeloid leukemia (AML): joint research by 23 institutions in Japan].

We evaluated the clinical course of acute myeloid leukemia (AML) and the levels of WT1 mRNA in 191 AML patients. Of 114 previously untreated patients with AML, 107 cases were positive for WT1 mRNA (93.9% : 107/114). WT1 mRNA expression-levels declined to below 50 copies/microg RNA ("negative") after remission was achieved in all 66 patients who achieved remission and 84.8% (47/54) cases were "negative" at the end of the follow-up periods. On the other hand, WT1 mRNA was expressed in 87.0% of non-remission cases (47/54), maintaining 50 copies/microg of RNA or higher ("positive"). In all 29 cases who relapsed during the follow-up observation period after achieving remission, WT1 mRNA levels declined transiently approximately around the time of achieving remission and then rose again when the disease relapsed. Moreover, we determined the time of elevation of WT1 mRNA in 29 relapsed cases. In 79.3% of relapsed cases (23/29), WT1 mRNA levels rose above 200 copies/microg RNA, 43 days (median) before the diagnosis of "relapse". Given the percent of the correct diagnosis, WT1 mRNA at 200 copies/microg RNA appeared to be a reasonable cut-off level for early detection of AML-relapse. The WT1 mRNA level reflected the clinical condition. Taken together, these findings indicate that WT1 mRNA levels allow us to detect the presence of so-called "minimal residual disease" (leukemic cells) that cannot be detected by morphological examination. Besides these promising data, this kit is suitable for routine monitoring of AML because this kit utilizes peripheral blood as a test specimen, reducing the patient's burden at the time of collection of clinical samples as compared with bone marrow aspirate.

Adult↗
PubMed2004

Targeted disruption of mouse ortholog of the human MYH9 responsible for macrothrombocytopenia with different organ involvement: hematological, nephrological, and otological studies of heterozygous KO mice.

Among three different isoforms of non-muscle myosin heavy chains (NMMHCs), only NMMHCA is associated with inherited human disease, called MYH9 disorders, characterized by macrothrombocytopenia and characteristic granulocyte inclusions. Here targeted gene disruption was performed to understand fundamental as well as pathological role of the gene for NMMHCA, MYH9. Heterozygous intercrosses yielded no homozygous animals among 552 births, suggesting that MYH9 expression is required for embryonic development. In contrast, MYH9+/- mice were viable and fertile without gross anatomical, hematological, and nephrological abnormalities. Immunofluorescence analysis also showed the normal cytoplasmic distribution of NMMHCA. We further measured the auditory brainstem response and found two of six MYH9+/- mice had hearing losses, whereas the remaining four were comparable to wild-type mice. Such observation may parallel the diverse expression of Alport's manifestations of human individuals with MYH9 disorders and suggest the limited requirement of the gene for maintenance and function of specific organs.

Animals↗
PubMed2004

Molecular cloning and characterization of ZFF29: a protein containing a unique Cys2His2 zinc-finger motif.

We have cloned a gene, ZFF29 (zinc-finger protein of human fetal liver erythroid cells 29), from human fetal liver erythroid cells. Two types of mature mRNA were identified and designated ZFF29a and ZFF29b. In human genome the ZFF29 gene is on chromosome 9q, and the two forms are splice variants. There is a unique transcription start site, which predicts major mRNAs composed of 2485 bases for ZFF29a and 1801 bases for ZFF29b. The anticipated mRNAs were demonstrated in K562 cells, but not in any adult human tissues examined by Northern blotting. In the mouse, reverse transcription-PCR revealed that the ZFF29 mRNA is present in adult bone marrow and ovary at a higher level than in any other tissues examined. These findings suggest that ZFF29 proteins are expressed in embryonic/fetal erythroid tissues. The deduced polypeptide chains of ZFF29a and ZFF29b are composed of 306 and 350 amino acids respectively. A unique zinc-finger motif composed of two contiguous Cys(2)His(2)-type fingers is common to both forms of ZFF29. They are nuclear proteins and ZFF29b, but not ZFF29a, is an activator of erythroid gene promoters.

Alternative Splicing↗
PubMed2004

Molecular evaluation of endothelial progenitor cells in patients with ischemic limbs: therapeutic effect by stem cell transplantation.

OBJECTIVE: Although some patients with limb ischemia have recently undergone therapeutic angiogenesis by cell transplantation, their angiogenic potential has not been well characterized. It is also important to evaluate endothelial progenitor cell (EPC) contents in different stem cell sources to choose the best material for therapeutic angiogenesis. METHODS AND RESULTS: We quantitated the mRNA expression of EPC-specific molecules (eg, Flk-1, Flt-1, CD133, VE-cadherin, etc) in bone marrow-derived or peripheral blood-derived mononuclear cells obtained from patients with ischemic limbs, using real-time reverse-transcription polymerase chain reaction technique. The mRNA expression level of EPC markers was significantly lower in the patients than in healthy controls, which was consistent with results of flow cytometric analysis. However, the implantation of autologous bone marrow mononuclear cells increased the circulating EPCs in the peripheral blood of patients. We furthermore revealed the different expression pattern of EPC markers in possible sources for stem cell transplantation, including normal bone marrow, peripheral blood obtained from recombinant granulocyte colony-stimulating factor-treated donor, and umbilical cord blood. CONCLUSIONS: Patients with peripheral obstructive arterial diseases may have lower angiogenic potential because of decreased expression of EPC specific molecules in their marrow and blood. Therapeutic angiogenesis by transplantation of autologous marrow mononuclear cells increased circulating EPCs in the patients and improved ischemic symptoms.

AC133 Antigen↗
PubMed2004

Combination of intensive chemotherapy and imatinib can rapidly induce high-quality complete remission for a majority of patients with newly diagnosed BCR-ABL-positive acute lymphoblastic leukemia.

The outcome for adult patients with BCR-ABL-positive acute lymphoblastic leukemia (ALL) remains dismal and long-term survival can hardly be achieved except by allogeneic hematopoietic stem cell transplantation (HSCT). The Japan Adult Leukemia Study Group (JALSG) has recently started a phase 2 trial with intensive chemotherapy and imatinib for newly diagnosed BCR-AB-positive ALL patients, and we present here the interim results for the first 24 patients. All patients except one case of early death (96%) attained complete remission (CR) after a single course of remission induction therapy. Polymerase chain reaction (PCR) negativity was achieved in 28% of the patients on day 28, in 50% on day 63, and in up to 78% during the follow-up period. The toxicity profile was almost similar to that with chemotherapy alone. As a result, 15 patients (63%) could receive an allogeneic HSC transplant during their first CR. Although the number of patients is small and the observation period is too short, the combination therapy is very promising and produces high-quality CR for most newly diagnosed patients with BCR-ABL-positive ALL. This is especially useful because it provides the patients with a better chance to receive an allogeneic HSC transplant.

Adolescent↗
PubMed2004

Expression cloning of oligomerization-activated genes with cell-proliferating potency by pseudotype retrovirus vector.

We developed a method of clone proliferation promoting fusion genes whose proteins were activated by protein oligomerization through the helix-loop-helix region (PNT domain) of TEL. We inserted a cDNA library downstream of the PNT domain with a retrovirus vector. The resulting retrovirus infected cytokine-dependent 32D cells and cells with cytokine-independent growth were analyzed for the inserted cDNA. We cloned 25 independent fusion genes including seven kinds of partner genes. Six of the seven were a fusion of TEL with protein tyrosine kinase, LYN, HCK, FGR, SYK, FLT3, and TYK2. A serine/threonine kinase, ARAF1, was also found to fuse with TEL. These kinase fusion proteins included kinase domains with proper reading frames. These fusions may be a useful model for clarifying the downstream signal transduction of constitutive active kinase and this expression cloning method may provide a new tool with which to study cell proliferation signalling.

Animals↗
PubMed2004

Phenylarsine oxide (PAO) more intensely induces apoptosis in acute promyelocytic leukemia and As2O3-resistant APL cell lines than As2O3 by activating the mitochondrial pathway.

We studied the cytotoxic effect of an organic arsenical compound, phenylarsine oxide (PAO) on an acute promyelocytic leukemia (APL) cell line (NB4) and an As2O3-resistant NB4 subline (NB4/As). Cell growth was inhibited by 50% (IC50) upon 2-day treatment with As2O3 or PAO at 0.54 and 0.06 microM, respectively in NB4 cells (P = 0.025), and 2.80 and 0.08 microM, respectively in NB4/As (P = 0.030). 0.1 microM PAO increased the proportion of hypodiploid cells (50.3%) by a greater degree than the same dose of As2O3 (3.8%) in NB4 cells. In NB4 cells, 0.1 microM PAO reduced the mitochondrial transmembrane potential (20.5% in a PI(negative)-Rhodamine123(low) fraction) by a greater degree than 1 microM As2O3 (7.1%). Western blotting showed that 0.1 microM PAO downregulated the expression of both Bcl-2 and Bcl-X(L) proteins, whereas I microM As2O3 downregulated only Bcl-2 expression. These results suggest that the cytotoxic effect of PAO on an APL cell line and As2O3-resistant subline is significantly higher than that of As2O3. PAO-induced apoptosis seems to be related to the activation of the mitochondrial pathway and downregulation of both Bcl-2 and Bcl-X(L). PAO is a considerable agent for relapsed/refractory APL and for purging APL cells following stem cell transplantation.

Apoptosis↗
PubMed2004

Polymorphisms of p53 Arg72Pro, p73 G4C14-to-A4T14 at exon 2 and p21 Ser31Arg and the risk of non-Hodgkin's lymphoma in Japanese.

We hypothesized that the polymorphisms in the two p53 family genes (p53 Arg72Pro and p73 G4C14-to-A4T14 at exon 2 (G4A)) and p21 Ser31Arg polymorphism might modulate the risk of non-Hodgkin's lymphoma, and conducted a hospital-based prevalent case control study at Aichi Cancer Center Hospital to clarify the association. Risk estimation for each genotype by the unconditional logistic model demonstrated the possible association between the p53 Pro72 allele and the risk of non-Hodgkin's lymphoma in Japanese population (OR = 1.59; 95% CI, 0.99-2.57, P = 0.057), although no other significant association was observed. The analyses of statistical interactions between these three polymorphisms (p73 G4A, p53 Arg72Pro and p21 Ser31Arg polymorphisms) revealed the marginally significant OR for interaction between p53 Arg72Pro and p73 G4A polymorphisms (OR = 2.54; 95% CI, 0.97 6.62, P = 0.057). When those without p53 Pro72 and p73 A4T14 alleles were defined as a reference, those with p53 Pro72 and p73 A4T14 alleles demonstrated a significantly higher OR (2.08; 95% CI, 1.11-3.90, P = 0.023). Further examination with a sufficiently larger population and other ethnicities are required to confirm our findings.

Adult↗
PubMed2004

Multiplex real-time RT-PCR for prospective evaluation of WT1 and fusion gene transcripts in newly diagnosed de novo acute myeloid leukemia.

Prognostic assessment is crucial for the management of AML. Although the use of karyotype analysis for risk-stratification is widely accepted, prognosis of AML remains ambiguous, particularly for patients categorized into the intermediate cytogenetic risk group and additional markers are required for an accurate prediction of outcome. For this study, we used multiplex real-time RT-PCR, which can simultaneously quantify WT1 and 10 distinct fusion gene transcripts, to prospectively evaluate the pre-treatment bone marrow findings of 53 de novo AML patients. Five patients with normal karyotype or insufficient metaphases detected by conventional karyotype analysis proved to have AML1-MTG8, CBFbeta-MYH11 or PML-RARalpha fusion transcripts. WT1 overexpression was observed in 92% of the patients, and the levels were significantly higher in the cytogenetic favorable risk group, especially patients with PML-RARalpha. WT1 levels also correlated with the percentage of blasts in bone marrow, especially in cases of core-binding factor leukemia. There was no association between initial WT1 levels and outcome in terms of event-free survival or overall survival. These results suggest that multiplex real-time RT-PCR is rapid and useful for the precise cytogenetic stratification of AML, and that WT1 levels at presentation correlate with several biologic features of leukemia, but have no prognostic significance.

Adolescent↗
PubMed2003

Altered interaction of HDAC5 with GATA-1 during MEL cell differentiation.

The transcription factor GATA-1 plays a significant role in erythroid differentiation and association with CBP stimulates its activity by acetylation. It is possible that histone deacetylases (HDACs) repress the activity of GATA-1. In the present study, we investigated whether class I and class II HDACs interact with GATA-1 to regulate its function and indeed, GATA-1 is directly associated with HDAC3, HDAC4 and HDAC5. The expression profiling and our previous observation that GATA-2 interacts with members of the HDAC family prompted us to investigate further the biological relevance of the interaction between GATA-1 and HDAC5. Coexpression of HDAC5 suppressed the transcriptional potential of GATA-1. Our results demonstrated that GATA-1 and HDAC5 colocalized to the nucleus of murine erythroleukemia (MEL) cells. Furthermore, a portion of HDAC5 moved to the cytoplasm concomitant with MEL cell erythroid differentiation, which was induced by treatment with N,N'-hexamethylenebisacetamide. These observations support the suggestion that control of the HDAC5 nucleocytoplasmic distribution might be associated with MEL cell differentiation, possibly through regulated GATA-1 transactivation.

Animals↗
PubMed2003

Biologic and clinical significance of the FLT3 transcript level in acute myeloid leukemia.

Although FLT3 mutations are essentially found in myeloid-lineage leukemia cells, a high level of FLT3 expression was recently observed in MLL gene-rearranged acute lymphoblastic leukemia without FLT3 mutations. Here, we analyzed the biologic and clinical significance of the FLT3 transcript level in comparison with several gene alterations in 181 de novo acute myeloid leukemia (AML) cases. The mean expression level in AML was higher than that in normal mononuclear cells, whereas the range varied widely. A high level of FLT3 is related to internal tandem duplication of the FLT3 gene (FLT3/ITD), the mutations within the activation loop of FLT3 (FLT3/D835Mt), and tandem duplication of the MLL gene (MLL-TD) but not to p53 or N-RAS gene mutations. Furthermore, a high expression level in AML cases with FLT3 mutations was not related to MLL-TD. Overexpressed FLT3 revealed autophosphorylation and had the same sensitivity to the FLT3 inhibitor as FLT3/ITD. Overexpression of FLT3 (more than 200,000 copies/microgRNA) was an unfavorable prognostic factor for overall survival in 91 AML cases without FLT3/ITD. These results indicated that FLT3 overexpression may distinguish a novel disease entity in AML without FLT3 mutations and serve as a therapeutic target for FLT3 inhibitors.

Adult↗
PubMed2003

Different antiapoptotic pathways between wild-type and mutated FLT3: insights into therapeutic targets in leukemia.

An internal tandem duplication (ITD) of the juxtamembrane (JM) domain of FLT3 (FLT3/ITD) has been found in 20% of patients with acute myeloid leukemia (AML) and is correlated with leukocytosis and a poor prognosis. Here, we compared the antiapoptotic effects of wild-type FLT3 (WtFLT3) and FLT3/ITD in terms of the regulation of Bcl-2 family members. In a murine myeloid cell line, 32D, interleukin-3 (IL-3) deprivation induced apoptosis following the down-regulation of Bcl-XL and the dephosphorylation of Bad. However, the expression levels of Bcl-2, Bax, Bak, and Mcl-1 were unchanged. In WtFLT3-transfected 32D (WtFLT3-32D) cells, FLT3 ligand (FL) stimulation did not restore the down-regulation of Bcl-XL but maintained the phosphorylation of Bad. Combined treatment with phosphatidylinositol 3-kinase (PI3K) inhibitor, LY294002, and mitogen-activated protein kinase kinase (MEK) inhibitor, PD98059, dephosphorylated Bad and induced apoptosis in WtFLT3-32D cells stimulated with FL. Induction of nonphosphorylated Bad induced remarkable apoptosis. These findings suggest that the FL stimulation is associated with antiapoptosis through Bad phosphorylation. On the other hand, FLT3/ITD-transfected 32D (FLT3/ITD-32D) cells survived in an IL-3-or FL-deprived state. Furthermore, the dephosphorylation of Bad using LY294002 and PD98059 was insufficient for apoptosis, and the down-regulation of Bcl-XL using antisense treatment was needed to induce apoptosis. FLT3 kinase inhibitor, AG1296, alone not only dephosphorylated Bad but also down-regulated Bcl-XL, leading FLT3/ITD-32D cells into apoptosis. These findings suggest that the antiapoptotic pathways from FLT3/ITD are more divergent than those from WtFLT3 and may represent targets for drug discovery with the potential of inducing selective cell death of human leukemia cells.

Apoptosis↗
PubMed2003

A xeno-transplantable plasma cell leukemia line with a split translocation of the IgH gene.

A novel cell line, SACHI, was established from a pericardial effusion developed during the course of primary plasma cell leukemia (PCL). The cell line SACHI cells were the same as the infiltrating plasma cells with regard to surface markers (CD38(+)CD19(-)PCA-1(+)VLA-5(-)CD56(-)TdT(+)) and immunoglobulin gene rearrangements. Analysis of SACHI cells showed a complex hypertriploid (karyotype mode 70-73) including 7p32, 14q32, and Xq24 structural abnormalities, which were found also in the original leukemia cells. Dual-color fluorescence in situ hybridization revealed that the c-MYC gene was juxtaposed with a constant region of IgG (Cgamma) on 14q32. The split Cgamma locus was fused near the MAFB gene on chromosome 20. The SACHI cells had increased amounts of c-MYC and MAFB transcripts. Injection of SACHI cells into NOD/SCID mice generated leukemic plasmacytosis with invasion to liver, spleen, and bone marrow. This cell line may be useful for therapeutic testing as well as analyzing the molecular pathogenesis of PCL.

Female↗