Kunio Kitamura

Ichinomiya Municipal Hospital, Itinomiya, Aichi, Japan

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Publications (25)170.46 Total impact

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    ABSTRACT: Eculizumab is a humanized monoclonal antibody that targets complement protein C5 and inhibits terminal complement-mediated hemolysis associated with paroxysmal nocturnal hemoglobinuria (PNH). The molecular basis for the poor response to eculizumab in a small population of Japanese patients is unclear. We assessed the sequences of the gene encoding C5 in patients with PNH who had either a good or poor response to eculizumab. We also evaluated the functional properties of C5 as it was encoded in these patients. Of 345 Japanese patients with PNH who received eculizumab, 11 patients had a poor response. All 11 had a single missense C5 heterozygous mutation, c.2654G → A, which predicts the polymorphism p.Arg885His. The prevalence of this mutation among the patients with PNH (3.2%) was similar to that among healthy Japanese persons (3.5%). This polymorphism was also identified in a Han Chinese population. A patient in Argentina of Asian ancestry who had a poor response had a very similar mutation, c.2653C → T, which predicts p.Arg885Cys. Nonmutant and mutant C5 both caused hemolysis in vitro, but only nonmutant C5 bound to and was blocked by eculizumab. In vitro hemolysis due to nonmutant and mutant C5 was completely blocked with the use of N19-8, a monoclonal antibody that binds to a different site on C5 than does eculizumab. The functional capacity of C5 variants with mutations at Arg885, together with their failure to undergo blockade by eculizumab, account for the poor response to this agent in patients who carry these mutations. (Funded by Alexion Pharmaceuticals and the Ministry of Health, Labor, and Welfare of Japan.).
    New England Journal of Medicine 02/2014; 370(7):632-9. DOI:10.1056/NEJMoa1311084 · 55.87 Impact Factor
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    ABSTRACT: Liu F, Asano N, Tatematsu A, Oyama T, Kitamura K, Suzuki K, Yamamoto K, Sakamoto N, Taniwaki M, Kinoshita T & Nakamura S (2012) Histopathology Plasmablastic lymphoma of the elderly: a clinicopathological comparison with age-related Epstein–Barr virus-associated B cell lymphoproliferative disorder Aims: Plasmablastic lymphoma (PBL) is an aggressive lymphoma with a terminally differentiated B cell phenotype; half of patients with this disease have Epstein–Barr virus (EBV) infection. The majority of PBL cases are associated with human immunodeficiency virus (HIV) infection, while the remaining HIV-negative cases were accompanied by other immunodeficiency conditions or immunosenescence in the elderly. Methods and results: To characterize HIV-negative PBL of the elderly (PBL-E), we compared the clinicopathological characteristics of 10 cases of PBL-E and 124 cases with age-related EBV-associated B cell lymphoproliferative disorder (AR-EBVLPD). The 10 PBL-E (eight men, two women; median age: 68 years) were associated with a more indolent clinical behaviour and a better overall survival than AR-EBVLPD. Extranodal involvement was higher in PBL-E (50%) than AR-EBVLPD; notably, the nasal cavity was affected most frequently in PBL-E (60%). Immunoglobulin heavy chain/(IGH)/MYC translocation was detected in half of the PBL-E cases. Conclusions: PBL-E shares some clinical features with AR-EBVLPD, such as HIV negativity, old age, and EBV infection, no known immunosuppressive condition but there are some differences such as a higher ratio of extranodal involvement and better prognosis. PBL-E is a newly recognized condition and should be distinguished from HIV-positive PBL, sharing features with AR-EBVLPD in particular, immunosenescence of the elderly.
    Histopathology 06/2012; 61(6). DOI:10.1111/j.1365-2559.2012.04339.x · 3.45 Impact Factor
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    ABSTRACT: Angioimmunoblastic T-cell lymphoma (AITL) is a major type of peripheral T-cell lymphoma (PTCL). To elucidate the clinicopathologic characteristics and prognosis of AITL in Japan, we retrospectively analyzed 207 patients with AITL. The median patient age was 67 years (range, 34-91 years), with 73% of patients older than 60 years. With a median follow-up of 42 months in surviving patients, 3-year overall survival (OS) was 54% and progression-free survival (PFS) was 38%. The International Prognostic Index (IPI) and the prognostic index for PTCL, not otherwise specified (PIT) were predictive for OS in this analysis. Multivariate analysis found that age older than 60 years, elevated white blood cell (WBC) and IgA levels, the presence of anemia and thrombocytopenia, and extranodal involvement at > 1 site were significant prognostic factors for OS, and IgA, anemia, and mediastinal lymphadenopathy were significant prognostic factors for PFS. A novel prognostic model consisting of the prognostic factors for OS was successfully constructed. In conclusion, IPI and PIT were still useful for prognostication of AITL, and other factors, including those not used in IPI, such as IgA, anemia, WBC count, thrombocytopenia, and mediastinal lymphadenopathy, also significantly affected prognosis. Future investigations for IgA as a unique prognostic factor are warranted.
    Blood 02/2012; 119(12):2837-43. DOI:10.1182/blood-2011-08-374371 · 10.45 Impact Factor
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    ABSTRACT: It was recently recognized that some chronic myeloid leukemia patients with a complete molecular response could sustain that response after discontinuation of imatinib. To characterize the clinical outcomes and profiles of chronic phase chronic myeloid leukemia patients who could discontinue imatinib, we conducted a nationwide survey in Japan. Among 3,242 imatinib-treated chronic myeloid leukemia patients, we identified 50 who had discontinued imatinib for at least six months; of these we analyzed 43. Molecular recurrence was detected in 19 patients, and a complete molecular response rate was estimated to be 47% following imatinib discontinuation. Based on multivariate regression analysis, imatinib dose intensity and prior interferon-α administration were independently predictive of molecular recurrence within 12 months. The depth of the molecular response should be a factor influencing long-term sustained complete molecular response after discontinuation of imatinib. Additionally, an immunological mechanism modified by interferon-α might control chronic myeloid leukemia stem cells.
    Haematologica 12/2011; 97(6):903-6. DOI:10.3324/haematol.2011.056853 · 5.81 Impact Factor
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    ABSTRACT: Primary gastric diffuse large B cell lymphoma (PG-DLBCL) is common subtype of extranodal non-Hodgkin lymphoma. The optimal treatment strategy for PG-DLBCL in the rituximab era still remains unknown. To evaluate clinical outcomes of PG-DLBCL in the rituximab era, we conducted a retrospective, multicenter analysis of 95 patients with PG-DLBCL. In 58 patients with localized disease, 3-year progression-free survival (PFS) and overall survival (OS) were 91% and 91% for patients with six cycles of rituximab plus CHOP (R-CHOP) and 92% and 95% for patients with three to four cycles of R-CHOP plus radiotherapy (Log-rank test, P = 0.595 and P = 0.278, respectively). In 37 patients with advanced disease, 3-year PFS and 3-year OS were 43% and 64% for patients with R-CHOP chemotherapy with or without radiotherapy. On multivariate analysis, advanced stage and elevated serum LDH levels were independent predictors of survival in patients with PG-DLBCL. One patient with localized disease relapsed in lymph node, and eight patients with advanced disease relapsed in lymph node (n = 3), stomach (n = 2), central nervous system (CNS; n = 2), and duodenum (n = 1). Intriguingly, CNS relapse developed within 6 months after initial series of treatment (4.9 and 5.8 months, respectively), and stomach relapse developed in later phase (27.2 and 32.9 months, respectively). Clinical outcomes of PG-DLBCL were extremely favorable for localized-stage patients in the rituximab era, although these might be poor for advanced-stage patients even in the rituximab era. Further prospective analyses are warranted.
    Annals of Hematology 08/2011; 91(3):383-90. DOI:10.1007/s00277-011-1306-0 · 2.63 Impact Factor
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    ABSTRACT: Early relapse is a parameter that affects clinical outcomes in relapsed diffuse large B cell lymphoma (DLBCL). The prognostic value of lymphopenia following the completion of first-line therapy and the relationship between lymphopenia and early relapse are unknown. Therefore, we studied the role of absolute lymphocyte count (ALC) on early relapse. We retrospectively analyzed de novo DLBCL patients who were treated with rituximab-containing treatment between 2003 and 2010. The median age at the time of diagnosis of 59 DLBCL patients was 71 years. We identified no association between ALC at diagnosis and ALC following the completion of first-line therapy. Among all patients analyzed, 13 (22%) patients were confirmed to exhibit early relapse. Low ALC following the completion of first-line therapy was significantly associated with early relapse by univariate analysis [hazard ratio (HR) = 4.05; 95% confidence interval (CI), 1.11-14.73; P = 0.02] and multivariate analysis (HR = 4.66; 95% CI, 1.24-17.48; P = 0.023). The low ALC group tended to have worse outcomes than the high ALC group with lower rates of progression-free survival (66% and 74%, respectively; P = 0.13) and overall survival (74% and 86%, respectively; P = 0.09), but these differences did not reach statistically. Lymphopenia following the completion of first-line therapy can be used as a marker to predict early relapse.
    Annals of Hematology 08/2011; 91(3):375-82. DOI:10.1007/s00277-011-1305-1 · 2.63 Impact Factor
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    ABSTRACT: Herpes zoster is the most common infection in patients treated with bortezomib-containing regimens for multiple myeloma. Some clinical trials have reported on the use of acyclovir prophylaxis to decrease the incidence of herpes zoster. However, the appropriate acyclovir dose and duration of prophylaxis remain unclear. The primary objective of this study was to evaluate the efficacy of continuous oral 200 mg/day acyclovir prophylaxis and the secondary objective was to determine the risk factors for developing herpes zoster. We collected medical information from consecutive patients who received bortezomib with or without acyclovir prophylaxis for relapsed or refractory multiple myeloma at our hospital and retrospectively analyzed the efficacy of acyclovir prophylaxis and the parameters for predicting the risk factors for developing herpes zoster. The definition of acyclovir prophylaxis was oral continuous administration of 200 mg of once daily, without cessation, during the entire period of bortezomib treatment. Six of the 33 patients in the study developed herpes zoster during bortezomib treatment. No varicella-zoster virus reactivation was observed in the 19 patients in the acyclovir prophylaxis group. The incidence of herpes zoster was significantly higher in the group that did not receive acyclovir prophylaxis (43%, 6 of 14 patients) than in the group that did (0%, 0 of 19; P = 0.003). The predictive factors for varicella-zoster virus reactivation were male sex (P = 0.035) and the use of acyclovir (P = 0.003). Continuous prophylaxis by oral 200 mg/day acyclovir in multiple myeloma patients receiving bortezomib treatment is effective and sufficient in preventing herpes zoster.
    Japanese Journal of Clinical Oncology 05/2011; 41(7):876-81. DOI:10.1093/jjco/hyr063 · 2.02 Impact Factor
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    ABSTRACT: BCR-ABL1 kinase domain mutations were evaluated in 60 imatinib-resistant patients with Philadelphia-positive (Ph(+)) leukemia using PCR-Invader assay and direct sequencing. In chronic myelogenous leukemia (CML)--chronic phase (CP), 5 had P-loop mutations and 3 had T315I mutations. CML-CP patients with high Sokal score showed significantly higher incidence of mutations. P-loop mutations were associated with higher risk of disease progression. In CML-advanced phase, P-loop mutations and T315I mutation were associated with significantly shorter survival. In Ph(+) acute lymphoblastic leukemia, overall survival was poor irrespective of mutational status. The PCR-Invader assay is useful for screening of mutations and prediction of prognosis.
    Leukemia research 05/2011; 35(5):598-603. DOI:10.1016/j.leukres.2010.12.006 · 2.35 Impact Factor
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    International journal of hematology 04/2011; 93(4):413-4. DOI:10.1007/s12185-011-0834-7 · 1.92 Impact Factor
  • Journal of Clinical Oncology 12/2010; 28(36):e750-2. DOI:10.1200/JCO.2010.30.5813 · 18.43 Impact Factor
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    ABSTRACT: This study investigated the clinical value of monitoring peripheral blood (PB) WT1 mRNA levels in acute myeloid leukemia (AML) patients. We evaluated the correlation between PB and bone marrow (BM) WT1 mRNA levels in the follow-up period of the clinical course of 17 AML patients. The levels of fusion gene transcripts in PB were also monitored when detected before chemotherapy. Patients with sustained complete remission (CR) showed a trend toward a higher WT1 mRNA reduction rate by induction therapy than patients who relapsed after CR (p=0.09). Correlation between the WT1 levels of PB and BM samples obtained on the same day was relatively strong (R=0.87). Among the four fusion transcript-positive patients, the levels of fusion transcripts and WT1 showed a similar transition pattern. These findings suggest that WT1 mRNA is a useful marker to improve risk-stratification for post-induction therapy and to guide management of individual AML patients by monitoring minimal residual disease, especially for patients with no disease-specific marker. Since WT1 monitoring via PB sampling is simple and less invasive than BM sampling, the use of this marker also improves patient management.
    [Rinshō ketsueki] The Japanese journal of clinical hematology 12/2010; 51(12):1748-55.
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    ABSTRACT: Pharmacokinetic (PK) factors have been suggested to be involved in the unfavorable clinical responses of chronic myeloid leukemia (CML) patients treated with imatinib. The purpose of this study was to clarify prognostic implications of PK factors in CML patients treated with imatinib. The plasma trough (C(min)) level of imatinib and serum α(1)-acid glycoprotein (AGP) level were measured on two different days in 65 CML patients treated with imatinib for more than 12 months. We further examined whether the C(min) level of imatinib actually reflects inhibitory activity against BCR-ABL kinase using the plasma inhibitory activity (PIA) assay. Since the differences of five patients were statistically rejected by the Smirnov-Grubbs' test, we excluded them for further analysis. The C(min) level was strongly associated with the achievement of MMR at the 12th month, and ROC analysis demonstrated C(min) levels and their discrimination potential for major molecular response (MMR) with the best sensitivity (63.2%) and specificity (68.2%) at a C(min) threshold of 974 ng/mL. The α(1)-Acid glycoprotein (AGP) level was within the normal range in 57 of 60 patients, indicating little impact of AGP on our study. There was a weak correlation between PIA against phospho (P)-BCR-ABL and the C(min) level of imatinib (r(2) = 0.2501, P = 0.0007), and patient plasma containing >974 ng/mL imatinib sufficiently inhibited P-BCR-ABL. These results collectively indicated that maintaining ∼1000 ng/mL of C(min) was clinically and biologically important for the optimal response in CML patients treated with imatinib. A prospective intervention study is required to establish PK-based management in CML patients treated with imatinib.
    Cancer Science 10/2010; 101(10):2186-92. DOI:10.1111/j.1349-7006.2010.01643.x · 3.52 Impact Factor
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    ABSTRACT: We retrospectively analyzed the potential of Wilms' tumor gene 1 (WT1) mRNA levels in peripheral blood for predicting the prognosis of 50 patients with AML. After achieving complete remission (CR), 34 patients (69.4%) were determined to be positive and 15 (30.6%) were negative for WT1. The relapse rate of the positive and negative patients was 73.5% and 40.0% (p = 0.02), respectively. After consolidation therapy, only 15 patients (32.6%) were positive and 31 (67.4%) were negative for WT1. Although the relapse rate of the positive and negative patients was 80.0% and 54.8% (p = 0.10), respectively, the rate of relapse within 1 year was 73.3% in positive patients and only 33.3% in negative patients (p = 0.01), respectively. The disease-free survival (DFS) rate at 3 years was 20.0% for positive patients and 50.0% for negative patients (p = 0.01). The overall survival (OS) rate at 3 years was 42.8% in positive patients and 69.8% in negative patients (p = 0.04), respectively. WT1 mRNA levels in the peripheral blood can predict relapse after CR, and its levels after consolidation therapy are closely correlated with DFS, OS, and early relapse.
    Leukemia & lymphoma 10/2010; 51(10):1855-61. DOI:10.3109/10428194.2010.507829 · 2.89 Impact Factor
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    ABSTRACT: Primary CNS diffuse large B-cell lymphoma (CNS DLBCL) is confined to the CNS, and constitutes a distinct entity. In the present study a series of 40 Japanese patients with CNS DLBCL who presented with neurological, but not systemic symptoms, was reviewed. Median survival was 18.7 months. CD5, CD10, Bcl-6, MUM-1, and Bcl-2 were positive in 30%, 10%, 84%, 100%, and 93% of patients, respectively. All CD10-negative patients had non-germinal center B-cell type. There was no significant difference in survival among the immunophenotypic subgroups. CNS DLBCL appeared to be homogenous as a group, which prompted the comparison with another distinct extranodal entity, intravascular large B-cell lymphoma (IVLBCL) in Japanese patients. CNS DLBCL patients did not differ in age, sex, or immunophenotype, including CD5 positivity, from IVLBCL patients, but were significantly less likely to have poor prognostic parameters than IVLBCL patients: the international prognostic index score was low or low-intermediate in 86% of CNS DLBCL patients and high or high-intermediate in 98% of IVLBCL patients. Notably, despite this difference, their survival curves almost overlapped. The present study highlights the issue of clinical distinctiveness of aggressive extranodal lymphomas, the peculiar migration and localization of which should be further clarified.
    Pathology International 08/2009; 59(7):431-7. DOI:10.1111/j.1440-1827.2009.02390.x · 1.69 Impact Factor
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    ABSTRACT: Chronic myelogenous leukemia (CML) is effectively treated with imatinib mesylate (IM), a small molecule inhibitor of the BCR-ABL tyrosine kinase that is expressed in the entire hematopoietic compartment including stem cells (HSC) and progenitors in CML patients. While IM induces disease remission, it does not appear to eradicate BCR-ABL-positive stem cells. We investigated the residual CML cells in HSC and myeloid progenitors isolated using fluorescence-activated cell sorting after IM-therapy. Quantitative real-time polymerase chain reaction detecting BCR-ABL transcripts showed that CML progenitors were eradicated within 12 months while the BCR-ABL-positive HSC remained. However, IM-therapy continuation could significantly decrease the ratio of BCR-ABL to BCR also in the HSC population. Our results implicate that the sorted and purified stem cells are useful for more sensitive quantification of BCR-ABL-positive minimal residual disease.
    International journal of hematology 12/2008; 88(5):471-5. DOI:10.1007/s12185-008-0221-1 · 1.92 Impact Factor
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    ABSTRACT: Classical Hodgkin's lymphoma (CHL) is characterized by Hodgkin's and Reed-Sternberg (H-RS) cells, most of which are derived from germinal-center B cells. Nevertheless, one or more markers for T cells and follicular dendritic cells (FDC) may be expressed in a minority of H-RS cells in some CHL patients, although the clinical significance of this remains controversial. The aim of this study was to clarify the association between phenotypic expression and clinical outcome in CHL. Participants were 324 consecutive CHL patients, comprising 132 patients with nodular sclerosis (NS), 35 patients with NS grade 2 (NS2), and 157 patients with mixed cellularity (MC). We evaluated the presenting features and prognosis of patients on categorization into four phenotypically defined groups: B-cell (CD20+ and/or CD79a+; n = 63), T-cell and/or cytotoxic molecules (CD3+, CD4+, CD8+, CD45RO+, TIA-1+, and/or granzyme B+; n = 27), FDC (CD21+ without B-cell marker; n = 22), and null-cell types (n = 212). Other potential prognostic factors were examined. The T-cell and/or cytotoxic molecules group showed a significantly poorer prognosis than the other three groups (P < .0001). This finding was seen consistently in multivariate analyses. Morphologic subtyping (NS/NS2/MC) and Epstein-Barr virus positivity were not identified as independent prognostic factors. The presence of T-cell and/or cytotoxic antigens in H-RS cells may represent a poor prognostic factor in CHL, even if their expression is not regarded as lineage specific. Examination of T-cell and/or cytotoxic molecules phenotype in CHL patients is recommended as a routine pathologic practice.
    Journal of Clinical Oncology 11/2006; 24(28):4626-33. DOI:10.1200/JCO.2006.06.5342 · 18.43 Impact Factor
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    ABSTRACT: Cytotoxic molecules (CMs) are apoptosis-inducing molecules that are present in azurophilic cytoplasmic granules of T lymphocytes. Expression of TIA-1 and granzyme B was examined for 100 cases of nodal peripheral T-cell lymphoma, unspecified (PTCL-U) to assess clinicopathologic significance of CM. Forty-one were positive for at least one CM. Patients with CM-positive PTCL-U showed younger onset (median, 55 years vs. 64 years, P = 0.01) and less male predominance (male:female ratio, 21:20 vs. 44:15, P = 0.02). CM-positive PTCL-U was significantly associated with several clinical factors to indicate poor prognosis, in comparison with CM-negative PTCL-U, such as poorer performance status (P = 0.006), more frequent B-symptoms (68% vs. 35%, P = 0.002), higher serum lactate dehydrogenase levels (P = 0.003), and more frequent extranodal involvement, particularly bone marrow involvement (33% vs. 9%, P = 0.004). Epstein-Barr virus was mostly found in CM-positive PTCL-U (51% vs. 2%, P < 0.0001). The CM-positive group showed higher distribution of the International Prognostic Index (P = 0.009) and the Prognostic Index for T-cell lymphoma (P = 0.004) scores than CM-negative group. Complete remission rate was 30% for the former but 63% for the latter. Overall survival of CM-positive PTCL-U was significantly lower than that of CM-negative patients (P = 0.004). Multivariate analyses confirmed that CM expression is a significant prognostic factor, independent from other clinical factors or prognostic index scores. These findings suggest that nodal CM-positive PTCL-U show distinct clinicopathologic characteristics among the current category of PTCL-U.
    American Journal of Surgical Pathology 11/2005; 29(10):1284-93. DOI:10.1097/01.pas.0000173238.17331.6b · 5.15 Impact Factor
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    ABSTRACT: 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.
    International Journal of Hematology 08/2005; 82(1):42-7. DOI:10.1532/IJH97.05013 · 1.92 Impact Factor
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    ABSTRACT: 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.
    Leukemia and Lymphoma 10/2004; 45(9):1803-8. DOI:10.1080/10428190410001693551 · 2.89 Impact Factor
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    ABSTRACT: 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.
    Leukemia and Lymphoma 06/2004; 45(5):987-95. DOI:10.1080/10428190310001617222 · 2.89 Impact Factor

Publication Stats

642 Citations
170.46 Total Impact Points


  • 2004–2014
    • Ichinomiya Municipal Hospital
      Itinomiya, Aichi, Japan
    • Hamamatsu University School of Medicine
      • Department of Internal Medicine II
      Hamamatu, Shizuoka, Japan
  • 2001
    • Dokkyo University
      Edo, Tōkyō, Japan
  • 2000
    • Nagoya University
      Nagoya, Aichi, Japan