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T Komeno

Publications and source records attributed to T Komeno.

At least 19 recordsLinked to original sources
PubMed2001

Detection of minimal residual disease in a patient having acute myelogenous leukemia with t(16;21)(p11;q22) treated by allogeneic bone marrow transplantation.

A 29-year-old woman having acute myelogeneous leukemia-M1 subtype with the chromosomal abnormality t(16;21)(p11;q22) is presented. Complete blood count at onset showed a hemoglobin level of 7.2 g/dl, a platelet count of 48 x 10(9)/l, and a white blood cell count of 161.2 x 10(9)/l with 99% blasts and 1% lymphocytes. Bone marrow aspiration revealed massive proliferation of blasts that were positive for CD13, CD33, CD34, CD56 and myeloperoxidase, and negative for other T-cell, B-cell and monocytic markers. After achieving complete remission following conventional chemotherapy, she received an HLA-matched bone marrow transplantation (BMT) from her sibling after conditioning with busulfan, etoposide and cyclophosphamide. However, 9 months later, the leukemia relapsed as a painful extramedullary mass in her left femur. In spite of intensive re-induction chemotherapy, she died of progressive disease and sepsis. Although we could not detect the TLS/FUS-ERG fusion transcripts by reverse transcriptase-polymerase chain reaction in pre-BMT remission phase, they were clearly detectable in bone marrow cells obtained 6 months after transplantation with no translocation detected by conventional cytogenetics. We consider that even high-dose chemotherapy with BMT may not be effective in the eradication of this type of leukemia, and that the detection of minimal residual disease possibly contributes to the better planning of the therapeutic strategy.

Adult↗
PubMed2000

Genetic defect in human X-linked agammaglobulinemia impedes a maturational evolution of pro-B cells into a later stage of pre-B cells in the B-cell differentiation pathway.

Surrogate light chains (lambda 5/VpreB) are selectively expressed in early precursors of B cells. B-cell defects in X-linked agammaglobulinemia (XLA) are caused by mutations in the gene for Bruton's tyrosine kinase. To elucidate the nature of early B-lineage cells in bone marrow (BM), samples from 13 XLA patients and 24 healthy controls of different ages were comparatively analyzed using an antihuman VpreB monoclonal antibody. Expression of surrogate light (SL) and mu-heavy chains were examined after cell membrane permeabilization because they are mainly expressed in the cytoplasm of early B-lineage cells. A flow cytometric analysis of normal BM identified 5 discrete cell types of B cells: mu(-)SL(++) (pro-B [B-cell progenitor]), mu(low)SL(++) (pre-B1a), mu(low)SL(+) (pre-B1b), mu(low)SL(- )(pre-B2), and mu(high)SL(- )(B). The large cells, presumably in cycling states, were enriched in pre-B1a cells. The frequencies of B-lineage cells in BM were higher in young children, and declined with advancing age. In contrast, XLA showed a profound reduction in BM B-lineage cells. In XLA BM, an expansion of pro-B cells with some small pre-B1a cells was marked, but other cells were negligible. These observations illustrate a B-cell maturation defect in XLA as well as a normal human B-cell differentiation pathway. The results suggest that the genetic defect in XLA may impede the evolution of pro-B cells beyond the earlier pre-B stage into the later stage of pre-B cells in B-cell development. (Blood. 2000;96:610-617)

Adolescent↗
PubMed2000

Nasal natural killer cell lymphoma in a post-renal transplant patient.

Posttransplant lymphoproliferative disorders in organ allograft recipients are most commonly of B-cell origin and only occasionally of T-cell origin. We present here a case of nasal natural killer cell lymphoma associated with Epstein-Barr virus that occurred in a recipient of a renal transplant 4 years posttransplantation. Immunohistochemically, the lymphoma cells showed CD2-, surface CD3-, cytoplasmic CD3E+, CD56+, CD57-, CD16-, and CD43+ phenotype. Analyses of T-cell receptor beta and gamma genes showed germ line configurations. EBER-1 was detectable in the lymphoma cells. The patient was diagnosed as having natural killer cell lymphoma and was treated with six courses of combination chemotherapy for non-Hodgkin's lymphoma He has been in remission for more than 3 years thereafter. To the best of our knowledge, this is the first report of a posttransplant NK cell lymphoma associated with Epstein-Barr virus.

Adult↗
PubMed2000

Chronic myelomonocytic leukemia derived from a possible common progenitor of monocytes and natural killer cells.

The neural cell adhesion molecule, CD56, is expressed on acute myelogenous leukemia (AML) cells in 17-20% of the patients. However, the clinical and biological significance of its expression in AML has not been well analyzed from the standpoint of CD56 expression and its association with differentiation to a natural killer (NK) cell lineage. Here we present a 78-year-old patient with chronic myelomonocytic leukemia (CMML) whose leukemic cells had features of both monocytes and NK cells. We demonstrated that the leukemic cells were positive for CD4, CD56 and interleukin-2 (IL-2) receptor beta chain (CD112) in addition to myelomonocytic markers such as CD33, CD11b and CD11c. These leukemic cells proliferated well in vitro in response to 10-100 U/ml of IL-2, and functionally showed significant cytotoxicity against K562 target cells in a 4-hour (51) Cr release assay. All the above data indicate that these cells possessed at least some of the biological features of NK cells. Accordingly, we speculate that the leukemic cells in this patient may have been derived from a possible common progenitor of monocytes and NK cells.

Aged↗
PubMed2000

Priming effects of macrophage colony-stimulating factor on monocytic leukemia cells in combination with chemotherapy: induction of programmed cell death in vivo.

Two elderly patients with chronic myelomonocytic leukemia were treated with cytosine arabinoside (Ara-C) and aclarubicin (ACR) under simultaneous administrations of macrophage colony-stimulating factor (M-CSF) (CAM), and both obtained good responses. Examination of apoptosis using flow cytometry revealed induction of apoptotic death of leukemia cells by CAM in Patient 2, while neither induction of apoptotic death of leukemia cells nor clinical response were seen with CAG (Ara-C, ACR, and granulocyte colony-stimulating factor) given prior to CAM in Patient 1. These findings suggested that chemotherapy combined with simultaneous administration of M-CSF could effectively reduce monocytic leukemia cells by inducing programmed cell death.

Aged↗
PubMed2000

Clinicopathological analyses of 5 Japanese patients with CD56+ primary cutaneous lymphomas.

We analyzed the clinicopathological features of 5 Japanese patients with CD56+ primary cutaneous lymphomas (3 men and 2 women aged 25 to 73 years). Except for 1 patient in whom bone marrow involvement was simultaneously observed, all patients presented with cutaneous lesions. Based on their Epstein-Barr virus (EBV) status, we categorized these patients into 2 groups, namely EBV-encoded small RNA-1 (EBER-1) (3 patients) and EBER-1- (2 patients). Generalized lymphadenopathy and bone marrow involvement were observed only in EBER-1 patients. Morphologically, angiocentric proliferation was more prominent in EBER-1+ patients and was accompanied by panniculitis-like changes. The lymphomas in EBER-1- patients featured monomorphic proliferation of lymphoblastic cells with no cytoplasmic granules. Phenotypically, CD3-, cytoplasmic CD3 epsilon+, and CD56+ were common findings in both types. The EBER-1- type showed an additional distinguishing feature, CD7+, CD4+, CD8-, HLA-DR+, and terminal deoxynucleotidyl transferase-positive (TdT+) phenotype. The lymphoma was primarily resistant in the EBER-1+ type, and the patients died within 6 months of admission. In contrast, the lymphoma in the EBER-1- patients was originally chemosensitive. Collectively, we consider there to be at least 2 types of CD56+ primary cutaneous lymphomas, corresponding to nasal-type natural killer (NK)/T-cell lymphomas (EBER-1+) and blastic NK-cell lymphomas (EBER-1-).

Adult↗
PubMed1999

Immature megakaryocytes undergo apoptosis in the absence of thrombopoietin.

We examined withdrawal effects of recombinant mouse Tpo (rm-Tpo) on the apoptosis of mature and immature megakaryocytes in in vitro experiments. Apoptotic megakaryocytes were detected by double staining for acetylcholinesterase and by the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method. When the purified mature megakaryocytes were cultured with or without rm-Tpo, the numbers of viable megakaryocytes, apoptotic megakaryocytes, and megakaryocytes with cytoplasmic processes were not significantly different between the two groups. In contrast, purified immature megakaryocytes underwent apoptosis when rm-Tpo was absent from the culture system. Murine bone marrow cells were cultured with rm-Tpo (50 U/mL) on days 1-7 to generate immature megakaryocytes and subsequently were cultured with different concentrations of rm-Tpo (0-50 U/mL) on days 8-14. The number of viable megakaryocytes was decreased and that of apoptotic megakaryocytes was increased by rm-Tpo in a dose-dependent manner. These results indicated a clear relation between the rm-Tpo level and the apoptosis of immature megakaryocytes.

Animals↗
PubMed1999

Priming with G-CSF effectively enhances low-dose Ara-C-induced in vivo apoptosis in myeloid leukemia cells.

We investigated the role of apoptosis in chemotherapy for hematologic malignancies. Twelve consecutive patients with acute myelogenous leukemia (AML) or refractory anemia with excess of blasts in transformation (RAEB-t) who were not tolerable for standard-dose chemotherapy were treated with CAG regimen (low-dose cytosine arabinoside [Ara-C] plus aclarubicin with concurrent administration of granulocyte colony-stimulating factor [G-CSF]). Bone marrow mononuclear cells obtained before the commencement of the chemotherapy were cultured with various concentrations (0-10(-5) M) of Ara-C in the presence or absence of 10 ng/mL of G-CSF, and the resultant cell proliferation/cytotoxicity was assayed. In all but one patient, half killing concentration (LC50) of Ara-C was significantly reduced in the presence of G-CSF (by 400- and 1.45-fold, median: 21-fold). Furthermore, LC(50) values in responders assayed in the presence of 10 ng/mL of G-CSF were significantly lower than those in nonresponders (p = 0.02). In vitro killing tests using a G-CSF-dependent leukemic cell line suggested that addition of G-CSF potentiates Ara-C-induced cytotoxicity through the mechanism of apoptosis. We thus assayed apoptosis in peripheral blood leukemic cells during CAG chemotherapy by flow cytometry using 7-amino-actinomycin D. Peak percentages of apoptosis in responders were significantly higher than those in nonresponders (p = 0.02). These results collectively suggest that apoptosis plays an important role for eradicating leukemic cells by CAG chemo-therapy.

Aged↗
PubMed1999

Non-Hodgkin's lymphoma followed by plasmacytoma, both arising in A thyroid gland with Hashimoto's disease.

We describe here a rare case of malignant lymphoma followed by plasmacytoma in Hashimoto's thyroiditis. The patient developed malignant lymphoma (small, non-cleaved cell, and non Burkitt's type by Working Formulation classification), and remained in remission for 2 years after receiving combination chemotherapy, and then developed plasmacytoma in the same lesion. Rearrangement bands for IgH from both specimens showed different bands, indicating that both were of monoclonal type but of a different clonal origin. Considering the clinical course in this case, thyroidectomy may be indicated for lymphoproliferative diseases in Hashimoto's thyroiditis treated with chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

High-dose chemotherapy with peripheral blood stem cell rescue in blastoid natural killer cell lymphoma.

A 25-year-old man was referred because of skin rash, lymphadenopathy and anemia. Laboratory examinations revealed severe anemia (Hb, 4.8 g/dl) and elevated levels of GOT, GPT, LDH and soluble interleukin-2 receptor. Work-up studies disclosed the involvement of lymphoma cells in lymph nodes, skin, bilateral kidneys and bone marrow. Lymph node biopsy revealed diffuse proliferation of medium- to large-sized lymphoblastic cells. Bone marrow aspiration showed massive infiltration of large blastic cells with no cytoplasmic granules. The lymphoma cells in bone marrow and lymph node showed surface CD3-, cytoplasmic CD3epsilon+, CD4+, CD8-, CD56+, CD57-, CD16- and CD43 (MT-1)+ phenotype. Analyses of T cell receptor beta and gamma genes showed germ line configurations. EBER-1 was not detectable in the lymphoma cells. He was diagnosed as having blastoid natural killer (NK) cell lymphoma. In spite of several courses of combination chemotherapy, the lymphoma was progressive. He was then treated with high-dose chemotherapy and peripheral blood stem cell rescue, achieving remission which has now lasted for more than 12 months. We consider that blastoid NK cell lymphoma is an extremely aggressive subtype of CD56-positive lymphomas, and high-dose chemotherapy with peripheral blood stem cell rescue should be included for the choice of the treatment.

Adult↗
PubMed1999

[T-cell prolymphocytic leukemia with CD4+8+25+ phenotype in a patient presenting with venous thrombosis in the lower leg].

A 58-year-old man was referred to our hospital because of painful swelling in the left lower leg and leukocytosis in January 1999. Moderate hepatosplenomegaly but no lymph node swelling was observed. Marked leukocytosis (leukocytes 44.9 x 10(4)/microliter with 95% morphologically prolymphocytes) and thrombocytopenia were detected. The surface phenotype of the leukemia cells was CD1-2+3+5+7+4+8+25+. Magnetic resonance imaging revealed dilated veins in the left lower leg. An abnormal 47XY, +22 karyotype was detected in 1/20 cells. Tests for HTLV-I antibody were negative. A diagnosis of T-cell prolymphocytic leukemia (T-PLL) was made on the basis of data including cytochemical and electron microscopic findings. Although 2 courses of chemotherapy comprising vincristine, cyclophosphamide, and prednisolone improved the venous thrombosis in the leg, the leukemia cells were refractory to chemotherapy. To prevent the recurrence of venous thrombosis due to leukostasis, the patient underwent repeated leukapheresis. The leukocyte count was maintained at around 20.0 x 10(4)/microliter after total 7 courses of leukapheresis, one course of which comprised 7l of extracorporeal circulation. In addition to the rare presentation of venous thrombosis, the CD4+8+25+ phenotype observed in this case is rare in patients with T-PLL.

CD4-CD8 Ratio↗
PubMed1998

Role of GATA-1 in proliferation and differentiation of definitive erythroid and megakaryocytic cells in vivo.

To elucidate the contributions of GATA-1 to definitive hematopoiesis in vivo, we have examined adult mice that were rendered genetically defective in GATA-1 synthesis (Takahashi et al, J Biol Chem 272:12611, 1997). Because the GATA-1 gene is located on the X chromosome, which is randomly inactivated in every cell, heterozygous females can bear either an active wild-type or mutant (referred to as GATA-1.05) GATA-1 allele, consequently leading to variable anemic severity. These heterozygous mutant mice usually developed normally, but they began to die after 5 months. These affected animals displayed marked splenomegaly, anemia, and thrombocytopenia. Proerythroblasts and megakaryocytes massively accumulated in the spleens of the heterozygotes, and we showed that the neomycin resistance gene (which is the positive selection marker in ES cells) was expressed profusely in the abnormally abundant cells generated in the GATA-1.05 mutant females. We also observed hematopoiesis outside of the bone marrow in the affected mutant mice. These data suggest that a small number of GATA-1.05 mutant hematopoietic progenitor cells begin to proliferate vigorously during early adulthood, but because the cells are unable to terminally differentiate, this leads to progenitor proliferation in the spleen and consequently death. Thus, GATA-1 plays important in vivo roles for directing definitive hematopoietic progenitors to differentiate along both the erythroid and megakaryocytic pathways. The GATA-1 heterozygous mutant mouse shows a phenotype that is analogous to human myelodysplastic syndrome and thus may serve as a useful model for this disorder.

Animals↗
PubMed1998

Anaplastic large-cell lymphoma of null-cell type with multiple bone involvement.

A 21-year-old man who had anaplastic large cell lymphoma (ALCL) of the null-cell type with multiple bone involvement is reported. On admission, he had symptoms of incomplete paraplegia and urinary and rectal incontinence. Workup studies for staging revealed para-aortic lymph node swellings and multiple bone involvement including skull, ribs, left iliac bone, and thoracic/lumbar spine. Because paraplegia was rapidly progressive, a decompression operation was performed. The biopsy specimen obtained from the lumbar spine revealed sheetlike proliferation of anaplastic large cells. These cells were positive for CD30 (Ki-1), EMA, vimentin, and p80NPM/ALK, and negative for CD3, CD20 (L26), and CD45 (LCA). Epstein-Barr virus-encoded small RNAs were not detectable in these cells. Thus, the patient was diagnosed as having ALCL of the null-cell type. He was treated with several courses of combination chemotherapy, and finally with total body irradiation plus high-dose chemotherapy supported by peripheral blood stem cell transplantation. However, soon after the treatment, the lymphoma cells massively infiltrated his bone marrow. He died of lymphoma 8 months after admission.

Adult↗
PubMed1998

Serum thrombopoietin level is mainly regulated by megakaryocyte mass rather than platelet mass in human subjects.

A patient with idiopathic thrombocytopenic purpura (ITP) developed T-cell lymphoma while undergoing steroid therapy. We examined the relationship between the patient's serum thrombopoietin (Tpo) level, platelet count, megakaryocyte number and CFU-Meg number during the second 5 d course of chemotherapy for lymphoma in which megakaryopoiesis switched from ITP phase to amegakaryocytic phase. The patient's platelet count was temporarily elevated but CFU-Meg numbers were markedly suppressed, and megakaryocyte numbers were decreased in this period, whereas serum Tpo level was not suppressed despite an increased platelet count, indicating that serum Tpo level is mainly regulated by megakaryocyte mass.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Ablation of Nrf2 function does not increase the erythroid or megakaryocytic cell lineage dysfunction caused by p45 NF-E2 gene disruption.

Maf recognition elements (MAREs or NF-E2 binding sites) have been shown to be vital for erythroid- and megakaryocyte-specific gene expression. Transcription factor NF-E2 is composed of p45, a large subunit belonging to the CNC family proteins, and a small Maf subunit, and is thought to activate transcription through its binding to MAREs in both the erythroid and megakaryocytic cell lineages. While p45 gene knockout mice exhibit thrombocytopenia due to abnormal terminal differentiation of megakaryocytes, and the mutant mice die of massive bleeding within a week after birth, anemia is not apparent in these animals. Disruption of the nrf2 gene, encoding another CNC family protein, results in no hematological abnormalities. We have therefore tested the hypothesis that Nrf2 might compensate for the p45 deficiency in erythroid lineage cells of p45-knockout mice, thereby masking the anticipated anemia. However, we failed to detect any greater failure in either erythroid or megakaryocytic cell development in Nrf2 plus p45 compound mutant mice as compared to with either individual homozygous mutation. These data suggest that p45 and Nrf2 may both be dispensable for hematopoietic cell development, and that other factors regulate erythroid- and megakaryocyte-specific gene expression through their required MAREs.

Anemia↗
PubMed1997

[Allopurinol induced pancytopenia in a patient with myeloproliferative disorder].

We reported a rare case of pancytopenia caused by allopurinol. A 61-year-old man was first admitted in May 1993, because of thrombocytosis. He had suffered from chronic glomerulonephritis. He was administered allopurinol for hyperuricemia from March 1993. On first admission the laboratory findings revealed leukocytosis (10,100/microliter) and thrombocytosis (971 x 10(3)/microliter) in the peripheral blood. Myelofibrosis was strongly suspected due to increased number of MgK and reticular fiber in the bone marrow. Two months later, he readmitted due to pancytopenia (WBC 1,300/microliter, Hb 6.2g/dl, Plt 10 x 10(3)/microliter). His bone marrow showed markedly hypocellular. Because we suspected that pancytopenia was induced by allopurinol, we discontinued allopurinol and administered oxymetholone, G-CSF, and EPO, WBC, RBC, and platelet count had been recovered about one and half months later. In vitro co-culture indicated that CFU-G, E, and Meg in the bone marrow cells after recovery from pancytopenia were markedly suppressed in the presence of patient's serum and oxipurinol. Pancytopenia due to allopurinol was reported to be rare, and some authors showed that it will sometimes be fatal. Because pancytopenia of this case had been recovered in a relatively short time with cytokine therapy, it was thought to be effective for pancytopenia due to drug like this case.

Allopurinol↗
PubMed1996

Chronic neutrophilic leukemia associated with monoclonal gammopathy of undetermined significance.

A 30-year-old man with chronic neutrophilic leukemia (CNL) in association with monoclonal gammopathy is presented. Physical examination on admission revealed moderate hepatosplenomegaly. Initial blood count showed neutrophilic leukocytosis (42.2 x 10(9)/1 with 90% mature neutrophils). Leukocyte alkaline phosphatase (LAP) score was elevated. Bone marrow aspiration showed myeloid hyperplasia without dysplastic features. Karyotypic and molecular analyses of bone marrow cells showed the absence of Philadelphia (Ph1) chromosome and bcr gene rearrangement. Because there was no underlying infection or neoplasm, he was diagnosed as having CNL associated with IgG kappa-type monoclonal gammopathy (IgG, 1,269 mg/dl). In addition to its association with monoclonal gammopathy of undetermined significance (MGUS), the present case was also characterized by spontaneous remission of CNL during the 12-year follow-up, accompanied by a gradual increase in serum IgG levels up to 3,000 mg/dl. As far as we know, there have been 19 cases of CNL associated with monoclonal gammopathy in the literature. The median survival of these cases was 5 years. Although there have been only 6 cases of CNL associated with MGUS, survival of these cases was particularly favorable. Taken together with the observation that leukocytosis and hepatosplenomegaly in the present case subsided without specific treatment, we speculate that myeloid proliferation in the present case may have been a leukemoid reaction to underlying monoclonal gammopathy.

Adult↗