Chihiro Shimazaki

Internal tandem duplication of FLT3 associated with leukocytosis in acute promyelocytic leukemia

FLT3 is a member of receptor tyrosine kinases expressed in leukemia cells, as well as in hematopoietic stem cells. Recently, a somatic alteration of the FLT3 gene was found in acute myeloid leukemia, as an internal tandem duplication (FLT3/ITD) which caused elongation of the juxtamembrane (JM) domain of FLT3. Here we characterized the FLT3/ITD and investigated its clinical significance in acute promyelocytic leukemia (APL). Seventy-four newly diagnosed patients with APL, who were treated with the same protocol in a multi-institutional study, were studied for the FLT3/ITD. Genomic and message sequences of the FLT3 gene were amplified by means of polymerase chain reaction (PCR), and elongated PCR products were sequenced. Fifteen patients (20.3%) had FLT3/ITD, all of which were transcribed in frame. Location of the duplicated fragments (six to 30 amino acids) varied from patient to patient. However, they always contained either Y591 or Y599, but the tyrosine kinase domain was not significantly affected. This finding implied that signal transduction of FLT3 is amplified by the duplication. Clinically, the presence of FLT3/ITD was related to high peripheral white blood cell counts as well as peripheral leukemia cell counts (P < 0.0001), high ldh level (P = 0.04), and low fibrinogen concentration (P = 0.04). These data suggest that FLT3/ITD plays a significant role in progression of APL.

Rituximab is effective for steroid-refractory sclerodermatous chronic graft-versus-host disease.

Chronic graft-versus-host disease (GVHD) is the most common late complication following allogeneic stem cell transplantation, occurring in 25–80% of transplant recipients.1 It is becoming a more frequent problem due to the increasing recipient age at transplantation as well as the increasing use of alternative donors, peripheral blood stem cells, and donor lymphocyte infusions. The most widely employed first line therapy for chronic GVHD is a combination of cyclosporine (CSA) and prednisolone, but patients who failed to respond to the initial steroid-based therapy have a poor outcome.1 Therefore, various agents have been investigated as salvage therapy for chronic GVHD, but there is no standard approach that is uniformly accepted.

B‐cell lymphoma associated with haemophagocytic syndrome: a clinical, immunological and cytogenetic study

B‐cell lymphoma associated with haemophagocytic syndrome (HPS) is extremely rare in Western countries but has recently been increasingly reported in Asian countries. We describe seven patients with B‐cell lymphoma associated with HPS, six males and one female, age range 41–82 years (median 63 years). All patients had fever and splenomegaly, and six of the seven patients had hepatomegaly with no associated lymphadenopathy. The bone marrow showed haemophagocytosis and an infiltration of lymphoma cells. All patients showed increased levels of lactate dehydrogenase, C‐reactive protein, ferritin and soluble interleukin‐2 receptor. Lymphoma cells were positive for CD19, CD20 and surface immunoglobulin in all patients examined, and positive for CD5 in four of seven patients. Cytogenetic analyses of bone marrow cells showed a complex structural abnormality including chromosome 14q32 in two patients, 19q13 in three patients and deletion of the terminal part of 8p21 in six patients. The prognosis was poor; only two of the seven patients have survived in complete remission with a median survival of 11 months. These data suggested that B‐cell lymphoma associated with HPS might constitute a distinct biological and clinical disease entity. Abnormality of chromosome 19q13 and loss of 8p21 might be involved in the pathogenesis of this disease.

B-Cell Lymphoma-Associated Hemophagocytic Syndrome

B-cell lymphoma-associated hemophagocytic syndrome (B-LAHS) is extremely rare in Western countries but has recently been increasingly reported in Asian countries, especially Japan. Here, we reviewed 25 previously reported Japanese cases of B-LAHS and summarized its clinicopathologic features and therapeutic outcome. The median age of onset was 63 years old with initial presentation of fever, hepatomegaly, and splenomegaly without associated lymphadenopathy. Laboratory findings showed increased levels of lactate dehydrogenase, C-reactive protein, ferritin and soluble interleukin-2 receptor. Histopathologically, hemo-phagocytosis was often seen in the bone marrow and spleen. Various percentages of lym-phoma cells were seen in the bone marrow, positive for CD19, CD20 and surface immunoglobulin, and some were also positive for CD5. Cytogenetic analysis showed a complex structural abnormality including chromosome 14q32, 19q13 and deletion of the terminal part of 8~21. Some patients had histological features of intravascular lymphomatosis (IVL). The prognosis was poor with a median survival period of 9 months. We treated five patients using autologous peripheral blood stem cell transplantation (PBSCT), and four are still in complete remission nine to 24 months after PBSCT, suggesting that high-dose chemotherapy followed by PBSCT might improve the survival rate.

Mobilization of hematopoietic primitive and committed progenitor cells into blood in mice by anti-vascular adhesion molecule-1 antibody alone or in combination with granulocyte colony-stimulating factor

OBJECTIVE One of the mechanisms for mobilization of hematopoietic stem cells and progenitor cells is alternation of adhesion molecules. We investigated the mobilization of hematopoietic progenitor cells in blood by administration of anti-vascular cell adhesion molecule (VCAM)-1 antibody (Ab) in mice. MATERIALS AND METHODS Twelve- to 14-week old C57BL/6J mice were injected intravenously with anti-VCAM-1 Ab and anti-very late antigen (VLA)-4 Ab at a dose of 5 mg/kg for 2 days. RESULTS The number of colony-forming cells (CFCs) in blood was increased 11.4-fold after anti-VCAM-1 Ab treatment, but the number of CFCs was not increased after treatment with anti-VLA-4 Ab. The number of colony-forming unit spleen (CFU-S) also was increased 21.6-fold in the peripheral blood by administration of anti-VCAM-1 Ab. The number of CFCs and CFU-S in the bone marrow of mice treated with anti-VCAM-1 Ab was decreased and that in the spleen also was decreased. On administration of recombinant human granulocyte colony-stimulating factor (125 microg/kg twice daily) with anti-VCAM-1 Ab, the numbers of CFCs and CFU-S were increased 141.8-fold and 439-fold, respectively. CONCLUSIONS These observations demonstrated that administration of anti-VCAM-1 Ab induced mobilization of hematopoietic progenitor cells into blood from bone marrow and spleen and that granulocyte colony-stimulating factor has synergistic effects on anti-VCAM-1 Ab-induced mobilization.

Prognostic significance of the null genotype of glutathione S-transferase-T1 in patients with acute myeloid leukemia: increased early death after chemotherapy

We investigated the prognostic significance of genetic polymorphism in glutathione-S transferase mu 1 (GSTM1), glutathione-S transferase theta 1 (GSTT1), NAD(P)H:quinone oxidoreductase (NQO1) and myeloperoxidase (MPO), the products of which are associated with drug metabolism as well as with detoxication, in 193 patients with de novo acute myeloid leukemia (AML) other than M3. Of the patients, 64.2% were either homozygous or heterozygous for GSTT1 (GSTT1+), while 35.8% showed homozygous deletions of GSTT1 (GSTT1−). The GSTT1− group had a worse prognosis than the GSTT1+ group (P = 0.04), whereas other genotypes did not affect the outcome. Multivariate analysis revealed that GSTT1− was an independent prognostic factor for overall survival (relative risk: 1.53; P = 0.026) but not for disease-free survival of 140 patients who achieved complete remission (CR). The rate of early death after the initiation of chemotherapy was higher in the GSTT1− group than the GSTT1+ group (within 45 days after initial chemotherapy, P = 0.073; within 120 days, P = 0.028), whereas CR rates and relapse frequencies were similar. The null genotype of GSTT1 might be associated with increased toxicity after chemotherapy.

High serum bone-specific alkaline phosphatase level after bortezomib-combined therapy in refractory multiple myeloma: possible role of bortezomib on osteoblast differentiation

High serum bone-specific alkaline phosphatase level after bortezomib-combined therapy in refractory multiple myeloma: possible role of bortezomib on osteoblast differentiation

A newly developed bisphosphonate, YM529, is a potent apoptosis inducer of human myeloma cells.

We examined the effect of YM529, a newly developed third-generation bisphosphonate (BP), on the growth of human myeloma cell lines using the trypan blue dye exclusion test and Alamar blue assay. BPs induced inhibition of proliferation in all cell lines dose-dependently, and YM529 had a most potent growth inhibitory effect, followed by incadronate and pamidronate. Flow cytometric analysis using annexinV and 7AAD showed that YM529 most significantly induced apoptosis of all myeloma cell lines. These observations suggested that YM529 is a potent apoptosis inducer of myeloma cells, and might have some benefit not only on the improvement of bone lesions but also on survival in some myeloma patients.

Prognostic value of p53 gene mutations and the product expression in de novo acute myeloid leukemia

Abstract: In acute myeloid leukemia (AML), p53 mutations are reportedly infrequent but associated with a poor prognosis. The majority of mutations are missense mutations, which generally lead to accumulation of nuclear p53 protein. However, the prognostic significance of the accumulation remains unknown in AML. In this study, we compared the prognostic value of p53 mutations versus accumulation of the product. p53 mutations were found in 9 (4.5%) of 200 patients with de novo AML. The p53 mutation detectable (mutation+) group had a worse prognosis (p=0.0009) than the mutation not detectable (mutation−) group. Multivariate analysis showed that the p53 mutation was an independent factor (p=0.005) for short overall survival as well as 60 yr or older (p=0.001) and unfavorable karyotypes (p=0.001). In 79 of the 200 patients, the expression of p53 was studied by immunocytochemistry (ICC) using anti‐p53 monoclonal antibody (DO‐7). All samples carrying missense mutations (N=6) were positive for ICC in over 15% of nuclei of each sample, chosen as the optimized cutoff value of p53 accumulation. Accumulation was thus found in 14 of the 79 patients. However, there was no prognostic difference according to the accumulation, because the mutation−/accumulation+ group (N=8) tended to have a good prognosis. These findings indicate that molecular detection of p53 mutations yields better prognostic information than ICC. In a subset of AML, p53 protein might be accumulated without mutation presumably due to upstream signals of p53.

Comparison of Human Herpes Virus 8 Related Primary Effusion Lymphoma with Human Herpes Virus 8 Unrelated Primary Effusion Lymphoma-Like Lymphoma on the Basis of HIV: Report of 2 Cases and Review of 212 Cases in the Literature

Background: Primary lymphomatous effusion is a rare lymphoma that arises in the body cavity and has a peculiar proliferative form, lacking a tumor. This primary lymphomatous effusion includes human herpes virus 8 (HHV8)-related primary effusion lymphoma (PEL) and HHV8-unrelated PEL-like lymphoma. We attempted to clarify the nature of the primary lymphomatous effusion. Methods: Using ‘PEL’ and ‘body cavity-based lymphoma’ (BCBL) as key words, reports written in English were collected from PubMed. Primary lymphomatous effusion was defined as BCBL with primary effusion and without tumor at onset. Adding our 2 PEL-like lymphoma cases, each case was studied as to the patients’ and lymphomas’ characteristics, therapy and survival time. Moreover, each item was compared among four groups according to the presence of HHV8 and HIV. Results: In 214 cases investigated, there was no difference in proliferation, but an apparent difference in age, gender, phenotype, effectiveness and prognosis among the four groups. Conclusions: Both PEL and PEL-like lymphoma are thought to be characterized by a peculiar proliferation, regardless of the presence of HHV8. Dividing PEL or PEL-like lymphoma into two subgroups on the basis of HIV presentation might also be appropriate.