Tsuyoshi Takami

Tumor-infiltrating myeloid-derived suppressor cells are pleiotropic-inflamed monocytes/macrophages that bear M1- and M2-type characteristics

Here, tumor‐infiltrating CD11b+ myelomonocytoid cells in murine colon adenocarcinoma‐38 and GL261 murine glioma were phenotypically characterized. Over 90% were of the CD11b+F4/80+ monocyte/macrophage lineage. They also had a myeloid‐derived suppressor cell (MDSC) phenotype, as they suppressed the proliferation of activated splenic CD8+ T cells and had a CD11b+CD11c+Gr‐1lowIL‐4Rα+ phenotype. In addition, the cells expressed CX3CR1 and CCR2 simultaneously, which are the markers of an inflammatory monocyte. The MDSCs expressed CD206, CXCL10, IL‐1β, and TNF‐α mRNAs. They also simultaneously expressed CXCL10 and CD206 proteins, which are typical, classical (M1) and alternative (M2) macrophage activation markers, respectively. Peritoneal exudate cells (PECs) strongly expressed CD36, CD206, and TGF‐β mRNA, which is characteristic of deactivated monocytes. The MDSCs also secreted TGF‐β, and in vitro culture of MDSCs and PECs with anti‐TGF‐β antibody recovered their ability to secrete NO. However, as a result of secretion of proinflammatory cytokines, MDSCs could not be categorized into deactivated monocyte/macrophages. Thus, tumor‐infiltrating MDSCs bear pleiotropic characteristics of M1 and M2 monocytes/macrophages. Furthermore, CD206 expression by tumor‐infiltrating MDSCs appears to be regulated by an autocrine mechanism that involves TGF‐β.

Nasal T-cell lymphoma as a type of so-called "lethal midline granuloma".

Six cases were described in which an initial clinical diagnosis of “rhinitis gangrenosa progressiva” or lethal midline granuloma was made. The histological examinations of their surgical and autopsy specimens proved that their nasologic diseases could all be identified as malignant lymphoma arising from the nasal cavity, showing the general histologic characteristics reported for T‐cell lymphomata derived from peripheral T‐cells. This histologic observation was then confirmed by immunofluorescence studies using various antisera directed toward either human T‐ or B‐cell‐surface antigens. These studies clearly demonstrated that their malignant cells bore human Ly‐l‐like antigen but lacked human TL‐like and la‐like antigens as well as surface‐bound immunoglobulins, indicating their peripheral T‐cell origin. These data may suggest that so‐called “rhinitis gangrenosa progressiva” or lethal midline granuloma contains at least two distinct disease categories, one of which is Wegeners granulomatosis, and the other of which is nasal T‐cell lymphoma as described herein.

Depletion of CD4+CD25+ regulatory T cells enhances interleukin-2-induced antitumor immunity in a mouse model of colon adenocarcinoma

Interleukin 2 (IL)‐2 induces antitumor immunity and clinical responses in melanoma and renal cell carcinoma. However, IL‐2 also increases the number of CD4+CD25+ regulatory T (Treg) cells that suppress antitumor immune responses. The aim of the present study was to elucidate the effect of depletion of Treg cells on IL‐2‐induced antitumor immunity. IL‐2‐transfected mouse colon adenocarcinoma (MC38/IL‐2) cells were implanted subcutaneously or intrahepatically into male C57BL/6 mice, and tumor growth and the proportion of tumor‐infiltrating lymphocytes with Treg‐cell depletion in response to treatment with anti‐CD25 monoclonal antibody (PC61) were determined. In mice treated with phosphate‐buffered saline, 40–60% of MC38/IL‐2 tumors were rejected. In contrast, all MC38/IL‐2 tumors were rejected in mice treated with PC61. The number of tumor‐infiltrating CD8+ T cells in mice treated with PC61 was approximately twice that in mice treated with PBS. The numbers of tumor‐infiltrating CD4+ and natural killer cells were also increased significantly. To test the antimetastatic effects of IL‐2 treatment in combination with Treg‐cell depletion, human recombinant IL‐2 (rIL‐2) and PC61 were administered to mice implanted with MC38/mock cells in the spleen, and hepatic metastasis was investigated. The average liver weight in mice treated with rIL‐2 plus PC61 was 1.04 ± 0.03 g, less than that in mice treated with rIL‐2 (2.04 ± 0.51 g) or PC61 alone (1.81 ± 0.38 g). We conclude that IL‐2‐induced antitumor immunity is enhanced by Treg‐cell depletion and is due to expansion of the tumor‐infiltrating cytotoxic CD8+ T‐cell population. (Cancer Sci 2007; 98: 416–423)

Prevalence of hepatitis B and C virus infection in haematological malignancies and liver injury following chemotherapy

Abstract:  The aim of this study was to determine the carrier rate of hepatitis virus in patients with haematological malignancies and the incidence of liver injury in these patients following chemotherapy. From January 1996 to September 2002, we studied 601 consecutive, unselected series of patients with haematological malignancies admitted in our hospital unit (Japan). They consisted of 246 cases of acute leukaemia, 218 non‐Hodgkins lymphoma (NHL), 13 adult T‐cell leukaemia, and 124 multiple myeloma. Of these 601 patients, 373 were men and 228 were women; their mean age was 61 yr, with a range from 18 to 89 yr. The prevalences of hepatitis B virus (HBV) and hepatitis C virus (HCV) were 7.3% and 10.1%, respectively, in NHL, both higher than those in acute leukaemia (1.7% and 2.9%, P < 0.005) and in general Japanese population (1.2% and 2.6%). The incidence of post‐chemotherapy liver injury in 25 HBV carriers (36.0%) was significantly higher than that in 539 non‐hepatitis virus carriers (12.6%, P = 0.003) and 37 HCV carriers (10.8%, P = 0.026). Liver injury in HBV carriers was more often present in patients who had been treated with steroids than in those without steroids (72.7% and 0%, P = 0.013). After lamivudine became available in our institution, the incidence of liver injury in HBV carriers was reduced from 53.3% to 10.0% (P = 0.041). The therapeutic strategy for haematological malignancies in hepatitis virus carriers should be further investigated.

Nucleolar Organizer Regions in Hepatocarcinogenesis Induced by N-2-Fluorenylacetamide in Rats: Comparison with Bromodeoxyuridine Immunohistochemistry

The number of silver‐stained nucleolar proteins (AgNOR) was counted in preneoplastic and neoplastic rat liver lesions induced by N‐2‐fluorenylacetamide (FAA) and was compared with that of bromodeoxyuridine (BrdU)‐incorporating cells detected immunohistochemically using monoclonal antibody against BrdU. Male ACI/N rats were given diet containing 200 ppm FAA for 12, 16 or 20 weeks to induce hepatocellular foci and tumors. The mean numbers of AgNOR stained by a one‐step silver colloid method and BrdU‐labeling indices in various liver cell lesions were as follows: nontreated liver (n = 20), 1.20 and 0.08; nonlesional areas (n=20), 1.33 and 0.13; altered liver cell foci (n = 80), 2.04 and 4.05 [eosinophilic cell type (n = 20), 1.78 and 1.82; clear cell type (n=20), 1.45 and 1.77; basophilic cell type (n=20), 1.99 and 4.58; hyperbasophilic cell type (n=20), 2.94 and 8.02]; neoplastic nodules (n = 10), 3.11 and 2.99; hepatocellular carcinomas (n = 10), 7.22 and 8.29. Thus, the mean number of AgNOR and the value of BrdU‐labeling index were well correlated and both values showed a stepwise increase from normal liver cells to liver cell carcinoma, although some scatter was present. These data suggest that mean number of AgNOR may reflect the cellular kinetics in rat hepatocarcinogenesis, and the one‐step silver colloid method for demonstration of AgNOR may therefore be a simple and useful staining to examine the proliferative nature of cells.

Epstein-Barr virus-associated B-cell lymphoma in a patient with DNA ligase IV (LIG4) syndrome.

A 14‐year‐old Japanese girl with a progressing combined immunodeficiency had developed non‐Hodgkins diffuse large B cell lymphoma. Her molecular analysis showed a compound heterozygote of novel mutations in the LIG4 gene, M249V substitution and a five nucleotides deletion from nucleotide position 1,270–1,274. She had also a set of characteristic clinical features of LIG4 syndrome. Mutations in the LIG4 gene, which plays a critical role in the repair of DNA double‐strand breaks, imply a correlation with malignancies and several cases with leukemia or lymphoma have already been reported. We report here on a case of LIG4 syndrome complicated with distinct EBV‐associated B‐cell lymphoma.

Endoscopic Ultrasound-Guided Fine Needle Aspiration Biopsy for Diagnosis of Lymphoproliferative Disorders: Feasibility of Immunohistological, Flow Cytometric, and Cytogenetic Assessments

OBJECTIVES:In addition to morphology, immunophenotype and genetic abnormalities should be assessed during diagnosis and subclassification of lymphoproliferative disorders. The objective of this study was to evaluate the yield of endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNAB) using a standard 19-gauge needle for diagnosis and subclassification of lymphoma, assessing the feasibility of immunohistological, flow cytometric, and cytogenetic assessments.METHODS:Two hundred forty patients with suspected lymphoma were referred for EUS-FNAB to our quaternary EUS center between June 2005 and December 2010. EUS-FNAB using a conventional 19-gauge needle was attempted for all patients, followed by histological assessments including immunohistological staining, flow cytometry, and cytogenetic analysis (G-band karyotyping). Among the patients, 152 were ultimately diagnosed with lymphoma. The primary outcome measure of this study was the sensitivity of histological assessment, including immunohistological staining, flow cytometry, and G-band karyotyping, for diagnosis and subclassification of lymphoma.RESULTS:Among the 152 patients ultimately diagnosed with lymphoma, 147 patients (96.7%) were diagnosed by EUS-FNAB, and classification in accordance with the WHO (World Health Organization) system was also possible for 135 patients (88.8%) on the basis of histological findings, including immunohistological staining. Flow cytometry showed abnormal or unusual cell populations in 121 (79.6%) of the 152 patients diagnosed with lymphoma, and in 114 (90.5%) of the 126 patients diagnosed with B-cell lymphoma. Specific cytogenetic abnormalities were detected in 21 (13.8%) of the lymphoma patients.CONCLUSIONS:EUS-FNAB using a standard 19-gauge needle has high diagnostic value for lymphoma. Immunophenotyping is usually possible, while cytogenetic abnormalities can be identified in a relatively limited number of patients.

Pathogenesis of Morquio A syndrome: An autopsied case reveals systemic storage disorder

Mucopolysaccharidosis IVA (MPS IVA; Morquio A syndrome) is a lysosomal storage disorder caused by deficiency of N-acetylgalactosamine-6-sulfate sulfatase, which results in systemic accumulation of glycosaminoglycans (GAGs), keratan sulfate and chondroitin-6-sulfate. Accumulation of these GAGs causes characteristic features as disproportionate dwarfism associated with skeletal deformities, genu valgum, pigeon chest, joint laxity, and kyphoscoliosis. However, the pathological mechanism of systemic skeletal dysplasia and involvement of other tissues remain unanswered in the paucity of availability of an autopsied case and successive systemic analyses of multiple tissues. We report here a 20-year-old male autopsied case with MPS IVA, who developed characteristic skeletal features by the age of 1.5 years and died of acute respiratory distress syndrome five days later after occipito-C1-C2 cervical fusion. We pathohistologically analyzed postmortem tissues including trachea, lung, thyroid, humerus, aorta, heart, liver, spleen, kidney, testes, bone marrow, and lumbar vertebrae. The postmortem tissues relevant with clinical findings demonstrated 1) systemic storage materials in multiple tissues beyond cartilage, 2) severely vacuolated and ballooned chondrocytes in trachea, humerus, vertebrae, and thyroid cartilage with disorganized extracellular matrix and poor ossification, 3) appearance of foam cells and macrophages in lung, aorta, heart valves, heart muscle, trachea, visceral organs, and bone marrow, and 4) storage of chondrotin-6-sulfate in aorta. This is the first autopsied case with MPS IVA whose multiple tissues have been analyzed pathohistologically and these pathological findings should provide a new insight into pathogenesis of MPS IVA.

Serum concentration of L-kynurenine predicts the clinical outcome of patients with diffuse large B-cell lymphoma treated with R-CHOP

Purpose: Introduction of rituximab has largely improved the prognosis of patients with diffuse large B‐cell lymphoma(DLBCL). Such change in therapeutic outcome necessitates the identification of additional prognostic factors to conventional indexes that have been validated for CHOP without rituximab. Indoleamine 2,3‐dioxygenase (IDO) exerts intense immunomodulatory effects because of enzymatic activities that catalyze the breakdown of the essential amino acid L‐tryptophan. The activity of IDO can be estimated by measuring the serum concentration of L‐kynurenine. Here, we investigated the role of L‐kynurenine as a prognostic marker in R‐CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone) therapy. Experimental design: Data from 73 consecutive patients treated with eight cycles of R‐CHOP or R‐THP (tetrahydropyranyl adriamycin)‐COP between December 2002 and March 2007 were analyzed. L‐kynurenine concentrations in serum samples obtained at admission were measured by high‐performance liquid chromatography. Results: The median serum L‐kynurenine level was 1.575 μm (range 0.537–9.588). The complete response (CR) rates of patients with L‐kynurenine <1.5 and ≥1.5 μm were 83% and 61%, respectively (P < 0.05). The three‐yr overall survival (OS) rates for patients with L‐kynurenine <1.5 and ≥1.5 μm were 89% and 58%, respectively (P < 0.005). In addition, higher age, poor performance status, elevated serum lactate dehydrogenase, and unfavorable as well as revised International Prognosis Index were significantly worse factors for CR rate and OS. Multivariate analyses revealed only L‐kynurenine as an independent prognostic factor for OS. Conclusions: Serum L‐kynurenine might be a novel prognostic factor to determine the treatment outcome of DLBCL with the R‐CHOP regimen.

Indoleamine 2,3-dioxygenase in tumor tissue indicates prognosis in patients with diffuse large B-cell lymphoma treated with R-CHOP

Indoleamine 2,3-dioxygenase (IDO) exerts immunomodulatory effects due to enzymatic activities catalyzing the essential amino acid l-tryptophan. IDO activity might play an important role in regulating immune responses exerted by antigen-presenting cells as a potent tool to help escape from assault by the immune system. In this study, we performed immunohistochemical analysis for IDO expression using mouse anti-human IDO monoclonal antibody in 119 tissue samples of diffuse large B-cell lymphoma (DLBCL) obtained before treatment with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Not only the lymphoma cells themselves but also dendritic cells (DCs) expressed IDO. Positive IDO expression in lymphoma cells was found in 38 cases (32%). Complete remission rates in patients with IDO-positive DLBCL and IDO-negative DLBCL were 55.3% and 79.0% (p = 0.008), while 3-year overall survival rates were 49.8% and 78.8%, respectively (p = 0.0003). IDO activity might thus play an important role in DLBCL and cells that express IDO appear important for determining outcomes after R-CHOP treatment. IDO might represent a candidate therapeutic target for DLBCL patients who show resistance to chemotherapy.