Shinobu Takahara

Interferon modulates the messenger RNA of G1-controlling genes to suppress the G1-to-S transition in Daudi cells

Interferon (IFN) is one of the potent antiproliferative cytokines and is used to treat some selected cancers. IFN arrests the growth of Burkitt Iymphoma derived cell line Daudi cells in the G1 phase. G1-to-S progression is controlled by positive and negative regulatory genes. Therefore, we investigated the effects of IFN on G1-controlling genes. Expression of cyclin-dependent kinases (Cdks 2, 3, 4, 5, 6), MO 15/Cdk7, and cyclins E and H was studied to assess positive regulators, while p15Ink4B, p16Ink4, p18, p21CipI, and p27Kip1 were assessed as negative regulators. Cdks 2, 4, 6 and cyclin E were markedly down-regulated. MO15/Cdk7 expression showed little change, but its regulatory subunit (cyclin H) was down-regulated like cyclin E. Expression of p15Ink4B and p16Ink4 was not observed. p18 was induced until 48 h and its expression returned to the initial level at 72 h. In contrast, p21Cip1 mRNA expression remained at the baseline level throughout IFN treatment, while the expression of p27Kip1 increased at 48 and 72 h. Taken together, these data indicate that IFN changes the messenger RNA of G1-controlling genes towards the suppression of G1-to-S transition.

Pseudo-Gaucher Cell Proliferation Associated with Myelodysplastic Syndrome

We report an extremely rare case of pseudo-Gaucher cell proliferation with myelodysplastic syndrome (MDS). A 77-year-old Japanese man was referred to our hospital with splenomegaly and thrombocytopenia, and subsequent bone marrow aspiration revealed infiltrates of foamy vacuolated macrophages without any evidence of other morphologic abnormalities. A karyotype analysis showed the presence of 46,XY,del(20)(q11) in 20 of 20 examined bone marrow cells. We performed a splenectomy, and the resulting pathologic findings revealed massive infiltration of foamy vacuolated macrophages, which were morphologically compatible with Gaucher cells. The activities of β-glucosidase and acid sphingomyelinase were within normal ranges; therefore, the foamy vacuolated macrophages were considered pseudo-Gaucher cells. A diagnosis of MDS, subclassified as refractory anemia, was then made according to World Health Organization classification guidelines. Pseudo-Gaucher cell proliferation and infiltration might therefore be observed in other patients presenting with MDS.

Band 3 Tokyo: Thr837-->Ala837 Substitution in Erythrocyte Band 3 Protein Associated with Spherocytic Hemolysis

We report a case of spherocytosis associated with erythrocyte band 3 deficiency. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of erythrocyte membrane proteins showed that the patient’s band 3 was reduced to about 80% of the control level. Molecular analysis revealed that this quantitative alteration was accompanied by a novel base change at codon 837 (ACG→GCG) of the AE1 gene, resulting in substitution of alanine for threonine. In bone marrow mononuclear cells, both mutant and wild-type mRNA were comparably detected, suggesting that this mutation interfered with band 3 processing or assembly, leading to impaired accumulation of mutant band 3 in the plasma membrane.

A case of primary esophageal mucosa-associated lymphoid tissue lymphoma with a numerical abnormality of 18q21 detected by fluorescence in situ hybridization.

Dear Editor, Mucosa-associated lymphoid tissue (MALT) lymphoma, which was first described in 1983. MALT lymphoma can develop from organs where lymphocytes are normally absent by the acquisition of MALT. The acquired MALT appears in association with chronic inflammation induced by persistent infection or autoimmune disorders such as Helicobacter pylori (H. pylori) infection, Sjogren’s syndrome, or Hashimoto’s disease. Although MALT lymphoma arises from any different organs, esophagus is a rare site of origin in the literature. We report here a primary esophageal MALT lymphoma with a numerical cytogenetic abnormality detected by fluorescence in situ hybridization (FISH). A 70-year-old woman has received endoscopy and submucosal tumors (SMT) were detected incidentally in October 2004. The examination revealed two SMT lesions (0.6×0.4 cm, 2.0×0.8 cm) approximately 26 and 28 cm from the incisor teeth (Fig. 1a). Histological examination of biopsied samples revealed that smallto medium-sized cells resembling marginal zone cells (Fig. 1b). Tumor cells were positive for CD20, CD79a, bcl-2, and negative for CD5, CD10, and cyclin D1. She had no episode of any autoimmune diseases or H. pylori gastritis. Computed tomography demonstrated no evidence of enlarged regional lymph nodes in the neck, chest, or abdomen. No bone marrow involvement was detected. We diagnosed her with primary esophageal MALT lymphoma. Endoscopic mucosal resection was performed in January 2005. Immunophenotypical analysis showed a kappa light chain restriction. FISH analysis was carried out using paraffin-embedded tissue with two differentially labeled probes each placed on upstream and downstream to MALT1, resulting three non-split signals (Fig. 1c). She received additional radiation therapy (30 Gy) after endoscopic mucosal resection. The patient is alive without any symptoms or recurrence of MALT lymphoma. MALT lymphoma exemplifies the close relationship between chronic inflammation and lymphomagenesis. It is well known that the most frequent primary involved site is the gastrointestinal tract. The lymphoma cells are preceded by the acquisition of MALT as a result of H. pylori infection. Eradication of H. pylori can result in regression of the lymphoma in 75% cases. However, additional genetic environmental or other factors should play a role, since most patients with H. pylori gastritis do not develop lymphoma. Recently cytogenetic data on MALT lymphoma has been accumulated. The t(11;18)(q21;q21) results in a Ann Hematol (2009) 88:703–704 DOI 10.1007/s00277-008-0653-y

A macrolide antibiotic, roxithromycin, inhibits the growth of human myeloid leukemia HL60 cells by producing multinucleate cells

The antiproliferative effect of roxithromycin (RXM) was studied using human myeloid leukemia HL60 cells. RXM inhibited the growth of HL60 cells in a concentration-dependent manner, and significantly inhibited growth at concentrations above 75 μM. This growth inhibition was not associated with specific cell cycle arrest and DNA synthesis was not impaired. In addition, the number of viable cells remained almost unchanged in the presence of 100 νM RXM. RXM induced growth inhibition at least partly by the formation of multinucleate cells. Both flowcytometric and morphological examination revealed that more than 40% of the RXM-treated cells were binucleate. These findings demonstrate that RXM is a potent new modulator of cell cycle progression in HL60 cells and suggest that the inhibition of cytokinesis by this drug may provide a new model for studying mitosis.

Diffuse large B‐cell lymphoma arising independently to lymphoplasmacytic lymphoma: a case of two lymphomas

Richters syndrome occurs in 5–10% of patients with chronic lymphocytic leukemia, either by transformation of the primary neoplastic lymphocyte, or as a distinct B‐cell neoplasm. We report a Japanese patient with lymphoplasmacytic lymphoma in whom a diffuse large B‐cell lymphoma developed after treatment with rituximab. Molecular examination on immunoglobulin VH genes revealed that the lymphomas had arisen in two separate clones. We reviewed clinical case reports in literature, and found 30–40% of cases with Richters syndrome and composite lymphoma had a second B‐cell lymphoma of a different origin.

Biological effects of a relatively low concentration of 1-beta-D-arabinofuranosylcytosine in K562 cells: alterations of the cell cycle, erythroid-differentiation, and apoptosis.

Therapeutic strategies for leukemia are directed to induction of differentiation and apoptosis as well as growth inhibition. One of the key antileukemic agents, 1-β-D-arabinofuranosylcytosine (ara C), is clinically applied according to these therapeutic aims. However, the molecular effects of 0.1 μg/ml of ara C, a concentration that corresponds to the serum level in leukemic patients on a conventional dose of ara C, have not been well disclosed. Here, we addressed these issues using K562 cells which derived from a blastic crisis of chronic myeloid leukemia. DNA synthesis of treated cells was suppressed from 1-6 h. But, it recovered at 12 h and no further inhibition was observed. The number of cells was not decreased but DNA fragmentation was observed at 72 h. The number of erythroid-differentiated cells also increased to 30% at 72 h. Along with treatment, no marked alteration of mRNAs for cell cycle-regulating genes was found and the retinoblastoma gene product remained hyperphosphorylated throughout treatment. The expression of mRNAs for apoptosis-regulating genes also remained unchanged, except for slight down-regulation of Bax. c-myc protein was not found later than 48 h, and Max mRNA was downregulated. c-jun was immediately induced, followed by the fluctuated expression level along with treatment. These findings suggest that the 0.1 μg/ml ara C changed the proliferation, differentiation and death of K562 cells in a biphasic manner. In the early phase, DNA synthesis was inhibited without altering the expression of cell cycle regulating-genes. In the latter phase, cell death and erythroid- differentiation occurred in accordance with the down-regulation of c-myc.

Rapid progression and unusual premortal diagnosis of mucormycosis in patients with hematologic malignancies: analysis of eight patients

Mucormycosis is a rare but emerging group of life-threatening opportunistic mycoses. We described experience of eight patients who developed mucormycosis. These patients had developed hematologic malignancies, and none achieved complete remission. Six of the eight patients presented with neutropenia, five received corticosteroid, and four had concomitant hyperglycemia. The most frequent physical finding was fever, and five patients complained of facial pain, headache, or chest pain. Four patients presented with concomitant bacterial infection, pulmonary aspergillosis, or intestinal candidiasis. Premortal diagnosis of mucormycosis was made in only one patient. Postmortem biopsy or autopsy was the diagnostic tool for the other patients. Although patients who were treated with amphotericin B survived longer than those treated with micafungin or voriconazole, all patients died due to the progression of mucormycosis. Estimated median survival was 23 days. Premortal diagnosis was rarely achieved as biopsy of infected tissues was the only diagnostic tool, and four patients who revealed dual infection were diagnosed with aspergillosis or bacterial infections. In patients with a high risk of mucormycosis presenting with pain and uncontrollable fever, mucormycosis should be included in the differential diagnosis. High dosages of liposomal amphotericin B should be given and surgical debridement should be performed promptly in cases highly suggestive of mucormycosis.

No V H Somatic Hypermutation Was Detected in B-Cells of a Patient with Macroglobulinemia Due to Splenic Marginal Zone Lymphoma

B-cell diseases are classified on the basis of the normal differentiation stages. We report here a case of a patient with a long history of leukocytosis, splenomegaly without lymphadenopathy, and hyperviscosity symptoms. Clinically, the patient’s diagnosis was leukemic Waldenström macroglobulinemia. Chromosomal analysis revealed translocation t(2;7)(p11;q22) along with disease progression. Death occurred from pulmonary infection at 46 months after the initial presentation. At autopsy, malignant lymphocytes were found in the marginal areas of the spleen with spreading to the bone marrow and the liver. The histologic findings were consistent with splenic marginal zone lymphoma. We examined the sequences of the immunoglobulin VH gene in cells from the initial peripheral blood and from the spleen at autopsy and found that the sequences were identical and had no somatic hypermutation. Macroglobulinemia can occur in various B-cell disorders, including splenic marginal zone lymphoma, even with the transformation of unmutated B-lymphocytes. Int J Hematol. 2002;76:453-459.

Carcinoembryonic antigen—producing multiple myeloma detected by a transcription—reverse transcription concerted reaction system

Multiple myeloma is a disease involving the clonal evolution of plasma cells that produce monoclonal immunoglobulin; however, other products, such as ammonia and amylase, reportedly are secreted by neoplastic plasma cells. We describe a patient with immunoglobulin A (IgA) myeloma who showed a high serum level of carcinoembryonic antigen (CEA) that correlated well with disease status and IgA level. We detected CEA-specific messenger RNA in plasma cells by means of a recently introduced rapid and quantitative RNA-amplification system, the transcription-reverse transcription concerted reaction system. This report is the first of a patient with a diagnosis of CEA-producing multiple myeloma.