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Biomedical subjects

Masahiro Kikuchi

Publications and source records attributed to Masahiro Kikuchi.

At least 37 records · Page 2Linked to original sources

Expression of FoxP3, a key molecule in CD4CD25 regulatory T cells, in adult T-cell leukaemia/lymphoma cells.

Adult T-cell leukaemia/lymphoma (ATLL) is an aggressive neoplastic disease that usually exhibits a CD4(+)CD25(+) phenotype. Regulatory T cells (Treg), which suppress T-cell effector function, are characterized by the co-expression of CD4 and CD25. We analysed the expression of forkhead/winged helix transcription factor (FoxP3), a specific marker that is important for the function of Treg, on ATLL cells from 17 patients (peripheral blood, n = 8; lymph node, n = 9). Real-time polymerase chain reaction and immunostaining detected FoxP3 expression in 10 ATLL cases, but was relatively down-regulated compared with Treg from normal subjects. These results indicate the association of ATLL and Treg.

Adult↗

Apoptosis- and cell cycle-associated gene expression profiling of histiocytic necrotising lymphadenitis.

Cell death is of two types; necrosis and apoptosis. In histiocytic necrotising lymphadenitis (HNL), apoptosis is the main form of cell death. Apoptosis results in the formation of nuclear debris, which is one of the characteristic features of HNL. We previously reported that in HNL it is predominantly CD8-positive cytotoxic T cells that undergo apoptosis; however, the majority of proliferating cells are also CD8-positive T cells. Recent advances in technical and analytical methods have facilitated the parallel quantitation of expression of numerous genes using DNA microarrays. The technology is particularly well suited to compare differences in gene expression between normal tissues and inflammatory disease. To investigate the apoptosis- and cell cycle-associated gene expression in HNL, we analysed five cases each of HNL and non-specific lymphadenitis (NSL), using ready-made microarrays, including cyclins and caspases, and immunohistochemical staining of caspase-3, ssDNA, bcl-2 and NF-kappaB. Caspase-3- and ssDNA-positive apoptotic cells were frequently detected in HNL, but were rare in NSL. However, bcl-2- and NF-kappaB-positive cells were rare in HNL. Gene expression tree analysis of DNA microarrays showed different clustering of HNL and NSL. In comparison with NSL, HNL exhibited diffuse upregulation of these gene profiles, particularly of cyclins and caspases (ratio; cyclin A2, 2.72; caspase-6, 2.43; caspase-3, 2.02); whereas, Mcl-1, which has been shown to delay apoptosis, was downregulated (ratio, 0.71), as confirmed by reverse transcriptase-polymerase chain reaction (RT-PCR). Almost all apoptosis-associated genes, especially caspases, were upregulated, and apoptosis inhibitory genes, including bcl-2 by immunohistochemistry, were downregulated in all five cases with HNL. In addition, cell cycle-associated genes were upregulated in all. These findings confirm that both apoptosis and proliferation are simultaneously present in HNL lesions.

Apoptosis↗

Very late central nervous system relapse in a patient with B cell lymphoblastic lymphoma.

Very late relapse of lymphoblastic lymphoma (LBL) is very rare. We report a case of a patient who developed central nervous system (CNS) relapse of LBL 16 years after the onset of the primary disease. An 8-year-old girl was hospitalized with a skin tumor in the occipital region on November 27, 1984. Examination of a biopsy of the skin tumor showed typical features of non-Hodgkin's lymphoma (diffuse medium-sized cell type). She received multiagent chemotherapy and went into remission. On July 4, 2000, she was hospitalized with persistent headache. Cranial magnetic resonance imaging showed a cerebellar lesion, which was hypointense on T1-weighted images and of heterogeneous intensity on T2-weighted images. A midline suboccipital craniotomy was performed and pathological examination revealed a diffuse proliferation of lymphoid cells, which were positive for terminal deoxynucleotidyl transferase, but negative for CD45RO, CD3 and CD20. Tumor cells stained positively for CD10, CD22, CD38 and HLA-DR. Revised immunohistochemistry of the primary specimens of skin tumor obtained 16 years earlier revealed a phenotype similar to that of the CNS disease. Polymerase chain reaction products for the immunoglobulin gene from both the skin and cerebellar specimens were an identical size. Thus, the original diagnosis of diffuse medium-sized lymphoma was revised to B cell LBL. An isolated CNS relapse of LBL was apparent in the present case. After salvage chemotherapy, the patient underwent high-dose chemotherapy with autologous peripheral blood stem cell support and subsequent craniospinal irradiation. She went into a lasting complete remission.

Cell Proliferation↗

Clinicopathologic analysis of 22 cases of subcutaneous panniculitis-like CD56- or CD56+ lymphoma and review of 44 other reported cases.

In 22 histologic cases of subcutaneous panniculitis-like lymphoma, we studied the clinicopathologic differences between CD56- and CD56+ cases (11 each). CD56- cases had skin ulcers (1 [9%]); tumor invasion in the superficial dermis (1 [9%]); erythrophagocytosis (10 [91%]); and medium-sized (11 [100%]), CD8+ (10 [91%]), T-cell receptor (TcR)betaF1+ (10 [91%]), and CD95 (Fas)- tumor cells. CD56+ cases had skin ulcers (9 [82%]); tumor invasion in the superficial dermis (8 [73%]); erythrophagocytosis (1 [9%]); and pleomorphic large (10 [91%]), CD8+ (2/10 [20%]), TcRbetaF1 + (3/10 [30%]), and CD95 (Fas)+ (7/10 [70%]) tumor cells. These 7 factors were significantly different between groups (P < .01). Median survival rates were 96 and 12 months for the CD56- and CD56+ groups, respectively. Age younger than 40 years, no skin ulcers, no tumor invasion in the superficial dermis, and CD8+, TcRbetaF1 +, CD95 (Fas)-, and CD56- tumor cells were significantly better prognostic factors (P < .01). The CD56- and CD56+ groups showed different tumor cell characteristics, clinicopathologic findings, and prognosis. In the CD56+ group, 1 was gamma/delta T-cell phenotype, 3 were alpha/beta T-cell, and 6 were TcRbetaF1- and gamma/delta- NK/T-cell, and 3 NK/T-cell cases had nuclear signals of Epstein-Barr virus-encoded RNA. Cases of CD56+ T- and NK/T-cell lymphoma had similar clinicopathologic findings and prognosis.

Adult↗

Expression of human tumor-associated antigen RCAS1 in adult T-cell leukemia/lymphoma.

In human cancer, RCAS1 (the receptor-binding cancer antigen expressed on SiSo cells) on the surface of various kinds of tumor cells reportedly induces the apoptosis of T-cells and natural killer cells, resulting in evasion of the immune system. In the present study, an immunohistochemical analysis of RCAS1 expression was performed with lymph node specimens obtained from patients with adult T-cell leukemia/lymphoma (ATLL). Positive staining was seen in 15 (75%) of 20 cases and in all cases of patients with short survival times. In the cases of B-cell lymphomas, positive staining was seen in only 1 (13%) of 8 cases. These findings indicate that expression of RCAS1 may be associated with the evasion from immune surveillance of cells infected with human T-lymphotropic virus type I, resulting in the development of overt leukemia/lymphoma. Determination of RCAS1 expression may be useful for predicting the prognosis of patients with ATLL.

Adult↗

Enhanced cementum formation in experimentally induced cementum defects of the root surface with the application of recombinant basic fibroblast growth factor in collagen gel in vivo.

BACKGROUND: Therapies using biologically active, soluble factors such as growth factors or cytokines have been investigated for potential clinical use in regenerating lost periodontal tissue due to periodontitis. Basic fibroblast growth factor (bFGF, FGF-2) is a multifunctional growth factor that has a variety of effects including induction of proliferation and morphogenesis in a wide range of cells and tissues including periodontal ligament tissue. METHODS: In this study, we examined the effects of bFGF on the regeneration of cementum and periodontal ligament in experimentally induced partial defects in a beagle dog model. bFGF in a collagen gel was applied to the defects and root surfaces, and the teeth were replanted. RESULTS: Eight weeks post-surgery, formation of cementum on denuded dentin was enhanced by application of 0.1, 1, or 5 microg of bFGF in a collagen gel compared to collagen gel containing vehicle. Histological analyses revealed that at 4 weeks post-surgery, random periodontal ligament fibers had bound to dentin, but were attached only to denuded dentin to which 0.1, 1, or 5 microg of bFGF in collagen gel had been applied. At 8 weeks post-surgery, we observed the formation of dense fibers bound to alveolar bone and newly synthesized cementum in teeth treated with 1 microg of bFGF. CONCLUSION: These results suggest that basic fibroblast growth factor in a collagen gel is a suitable therapy for damaged periodontal ligament and could lead to readily achievable methods of treatment for periodontal disease.

Alveolar Process↗

Effects of the overexpression of fructose-1,6-bisphosphate aldolase on fermentation pattern and transcription of the genes encoding lactate dehydrogenase and pyruvate formate-lyase in a ruminal bacterium, Streptococcus bovis.

Whether fructose-1,6-bisphosphate (FBP) triggers the transcriptional regulation of the gene expression of lactate dehydrogenase (LDH) and pyruvate formate-lyase (PFL) in Streptococcus bovis was examined by constructing a recombinant strain that overexpresses FBP aldolase (FBA). When the recombinant strain was grown on glucose, intracellular FBP was much lower as compared to the parent strain, whereas dihydroxyacetone phosphate (DHAP) and d-glyceraldehyde-3-phosphate (GAP) were slightly higher. Intracellular ATP and ADP were slightly lower, but the NADH/NAD(+) ratio was not different. When glucose was replaced by lactose, a less readily utilized substrate, there was no great difference in FBP, DHAP, GAP, or adenine nucleotides. Overexpression of FBA decreased the level of LDH-mRNA, and increased the level of PFL-mRNA. Consequently, FBP concentration was positively related to the LDH-mRNA level and inversely related to the PFL-mRNA level. On the contrary, DHAP and GAP concentrations were positively related to the PFL-mRNA level and inversely related to the LDH-mRNA level. The levels of these mRNA were proportional to the amounts of corresponding enzymes in cells. As a result, the ratio of formate to lactate produced was increased by the overexpression of FBA. From these results, it could be presumed that FBP is involved in the transcriptional control of LDH and PFL synthesis in S. bovis.

Acetyltransferases↗

Chromosomal imbalances in angioleiomyomas by comparative genomic hybridization.

Angioleiomyoma is a benign soft tissue tumor that usually develops in the subcutis of the lower extremities. It characteristically consists of thick vessel walls formed by proliferating smooth muscle cells, and vascular channels. Very little is known about the molecular cytogenetic changes in angioleiomyoma. In the present study, we employed comparative genomic hybridization (CGH) to identify relative DNA copy number changes in 33 angioleiomyomas using formalin-fixed and paraffin-embedded tumor tissues. CGH results were obtained in 23 (70%) cases. Eight (35%) of the 23 cases exhibited DNA copy number changes involving one or two chromosomes, whereas the remaining 15 cases exhibited no DNA copy number changes. The most common recurrent loss was found in chromosome 22 (the minimal common region was 22q11.2 in five cases). Recurrent gain was seen at Xq (three cases). High-level amplification was not observed. To our knowledge, this is the first report on molecular cytogenetic characterization of angioleiomyomas using CGH from formalin-fixed and paraffin-embedded specimen. The present study has identified chromosomal regions that may contain genes involved in the development of at least some angioleiomyomas.

Adult↗

Differential expression of chemokines, chemokine receptors, cytokines and cytokine receptors in diffuse large B cell malignant lymphoma.

Host immunity, particularly T cell immunity (Th1/Th2 balance), plays an important role in clinicopathological features of malignant disease. However, the T cell immunity has not been fully investigated in patients with lymphoid malignancies. Recent studies suggested the important role of dysregulation of the endogenous immune system in lymphomagenesis. The relationships between cytokines/chemokines and their receptors, are important in determining the selectivity of local immunity. To investigate differences in the endogenous immune system of diffuse large B cell lymphoma (DLBL), we performed gene expression profiling using cDNA microarrays of cytokines/chemokines and their receptors. We studied 5 cases each of primary central nervous system lymphomas (PCNSL), extranodal and nodal lymphomas. PCNSL exhibited diffuse down-regulated profiles, compared to normal peripheral blood lymphocytes. While extranodal and nodal lymphomas also exhibited diffuse down-regulated profiles, some genes displayed up-regulated profiles. Hierarchical clustering analysis separated PCNSL and extranodal lymphomas into distinct groups based on their gene expression profiles, as well as extranodal and nodal, but not PCNSL and nodal. PCNSL exhibited significantly lower expression of BLC/BCA-1 and CCR-3 (Th2 type), and higher expression of IL-8 and MIP-1beta (Th1 type) than extranodal lymphomas. Immunohistochemistry and RT-PCR revealed frequent CCR-3 and BLC/BCA-1 expression in extranodal lymphomas, compared with PCNSL. Our results provide new insights into the pathogenesis of each DLBL. A better understanding of the immune response in each DLBL could help in the design of novel therapeutic strategies based on cytokines/chemokines and their receptors.

Adult↗

Comparative study of primary mammary small cell carcinoma, carcinoma with endocrine features and invasive ductal carcinoma.

Mammary small cell carcinoma (SmCC) is a very rare neoplasm with a poor prognosis compared with other invasive carcinomas. We studied the histological and immunohistochemical profiles of two cases of mammary SmCC, and compared them with those of five cases of carcinoma with endocrine features (CEF) and five cases of invasive ductal carcinoma (IDC), to elucidate the correct diagnosis of mammary SmCC. Immunohistochemical analysis was performed with antibodies against cytokeratins (CKAE1/AE3, CK34betaE12, CKCAM5.2, CK7, CK8, CK19, CK20), epithelial membrane antigen (EMA), vimentin, CD10, neural cell adhesion molecule (NCAM; CD56), neuron-specific enolase (NSE), chromogranin A, S-100 protein, carcino-embryonic antigen (CEA), E-cadherin, N-cadherin, thyroid transcription factor-1 (TTF-1), p53, estrogen (ER), progesterone (PR), HER2/neu, bcl-2, synaptophysin, calcitonin and Leu7. SmCCs were diffusely and strongly positive for NCAM in comparison with CEFs and IDCs. SmCCs were negative for vimentin, whereas CEFs and IDCs were positive. Neuro-endocrine carcinomas, including SmCCs and CEFs, were diffusely and strongly positive for NSE, compared with IDCs. Moreover, neuroendocrine carcinomas were negative for CK34betaE12, CK20 and CD10, whereas IDCs were positive. Our study suggests that NCAM and vimentin are useful markers for the diagnosis of mammary SmCC. CK34betaE12, NSE, CD10, CK20 and chromogranin A appear to be useful for differentiating neuroendocrine carcinoma from IDCs.

Aged↗

Clinicopathological states of Epstein-Barr virus-associated T/NK-cell lymphoproliferative disorders (severe chronic active EBV infection) of children and young adults.

Epstein-Barr virus (EBV)-associated T/NK-cell lymphoproliferative disorders (LPD) of children and young adults are sometimes termed as severe chronic active EBV infection (CAEBV), and are associated with an aggressive clinical course. However, these clinicopathological states and the role of EBV have not been clarified. A retrospective study was performed on 43 children and adult patients, who manifested EBV-associated T/NK-cell lymphoproliferative disorders (EBV-T/NK-LPD) and most of whom had experienced general illness with CAEBV for several months or years. Clinicopathologically, 43 patients were classified into four groups: group A (smoldering state) (n=7), morphological non-neoplastic LPD with chronic clinical course (several years); group B (chronic state) (n=10), non-neoplastic LPD with clonal EBV-infected cells and a chronic course; group C (leukemia/lymphoma state) (n=22), neoplastic LPD with a subacute course (years to months); group D (fulminant state) (n=4), neoplastic LPD with a fulminant course (weeks to days). The 43 patients comprised 21 males and 22 females. The median age of group A was 14 years, group B 12 years, group C 17 years, and group D 1 year. Four of 7 patients in group A, 3 of 10 in group B, 12 of 22 in group C, and all 4 in group D have died. Causes of death included hemophagocytic syndrome and/or tumor death. Genotypically and phenotypically, group C was composed of peripheral T-cell lymphoma (PTCL), and NK-cell leukemia/lymphoma (NKLL), and group D comprised cases of PTCL. Groups A and B exhibited increased NK- or T-cells (CD8>CD4), and rare B-cells. Serologic titers of EBV were only modestly elevated or not elevated in almost all cases. EBV early RNA-1 (EBER-1)-expressing EBV-infected cells were frequently encountered in each group, but the number of infected cells varied between the cases. The EBV genotype did not differ between the groups. Our findings support an important pathogenic role for EBV-infected T/NK-cell infection, rather than the EBV state, in CAEBV and consequent EBV-associated NK/T-neoplasia.

Adolescent↗

Radiation response mechanisms of the extremely radioresistant bacterium Deinococcus radiodurans.

Effect of microgravity on recovery of bacterial cells from radiation damage was examined in IML-2, S/MM-4 and S/MM-9 experiments using the extremely radioresistant bacterium Deinococcus radiodurans. The cells were irradiated with gamma rays before the space flight and incubated on board the Space Shuttle. The survival of the wild type cells incubated in space increased compared with the ground controls, suggesting that the recovery of this bacterium from radiation damage was enhanced under the space environment. No difference was observed between the survivals of radiosensitive mutant rec30 cells incubated in space and on the ground. The amount of DNA-repair related RecA protein induced under microgravity was similar to those of ground controls, however, induction of PprA protein, product of a unique radiation-inducible gene (designated pprA) responsible for loss of radiation resistance in repair-deficient mutant, KH311, was enhanced under microgravity compared with ground controls. Recent investigation in vitro showed that PprA preferentially bound to double-stranded DNA carrying strand breaks, inhibited Escherichia coli exonuclease III activity, and stimulated the DNA end-joining reaction catalyzed by DNA ligases. These results suggest that D. radiodurans has a radiation-induced non-homologous end-joining (NHEJ) repair mechanism in which PprA plays a critical role.

Bacterial Proteins↗

Imbalances of chemokines, chemokine receptors and cytokines in Hodgkin lymphoma: classical Hodgkin lymphoma vs. Hodgkin-like ATLL.

Classical Hodgkin lymphoma (HL) is characterized by the presence of Hodgkin and Reed-Sternberg cells (H&RS) and a prominent lymphocytic infiltration. We previously reported Hodgkin-like adult T-cell leukemia/lymphoma (HL-like ATLL) (new WHO classification). Various CXC and CC chemokines are expressed on H&RS cells and the relationships between chemokines and the chemokine receptor (R) are thought to be important for selectivity of local immunity of Th1 and Th2 T cells. To clarify the role of T-cell immunity in classical HL and Hodgkin-like ATLL, we performed gene expression profiling (chemokine, chemokine R and cytokine DNA chips) in 12 cases [classical HL, 8 cases [mixed cellularity (MC) type, 4; nodular sclerosis (NS) type, 4]; Hodgkin-like ATLL, 4 cases] and immunohistochemical staining in 29 cases (MC, 10; NS, 10; Hodgkin-like ATLL, 9). EBV-infected H&RS cells were detected in 9 of 10 cases of HL MC, 5 of 9 of HL-like ATLL and 2 of 10 HL NS. T-cell-directed chemokine thymus- and activation-regulated chemokine (TARC)- and/or macrophage-derived chemokine (MDC)-positive H&RS cells were detected in all 20 cases of HL MC and HL NS but only in 5 of 9 cases of HL-like ATLL. Interferon-gamma-inducible protein-10 (IP10)- and monokine induced by interferon-gamma (MIG)-positive H&RS cells were detected in all 10 HL MC but only in 5 of 10 cases of HL NS and 2 of 9 cases of HL-like ATLL. However, 2 of 5 cases of HL-like ATLL with EBV infection and 2 of 2 HL NS with EBV had IP10/MIG-positive H&RS cells. The chemokine expressions in H&RS cells seemed to be associated with EBV infection rather than histologic subtypes. In the DNA chip expression analysis, classical HL and HL-like ATLL had a mixed Th1/Th2-type profile, and HL MC (EBV-positive) and HL NS (EBV-negative) were differentially clustered. However, 2 cases of HL-like ATLL clustered with HL MS and the other 2 cases of HL-like ATLL clustered with HL NS. The former HL-like ATLL had EBV infection in H&RS cells, whereas the latter did not have EBV infection. This finding also suggests that EBV might influence local expression of chemokines rather than HL subtypes. Our results indicate that local immunologic disorder or imbalance appears to influence the formation of H&RS cells and that in HL-like ATLL, HTLV-1 infection might not be necessary for H&RS cell formation.

Chemokines↗

Th1, Th2, and activated T-cell marker and clinical prognosis in peripheral T-cell lymphoma, unspecified: comparison with AILD, ALCL, lymphoblastic lymphoma, and ATLL.

A new World Health Organization classification was recently proposed. However, classification of peripheral T-cell lymphomas remains to be clarified. Particularly, unspecified type was considered as a heterogeneous category. Here we studied the expressions of chemokine receptors, Th1-associated CXCR3 and CCR5 and Th2-associated marker ST2(L), and activated T-cell receptor OX40/CD134 in 185 patients with nodal T-cell lymphoma, and evaluated the relationship to prognosis. Their expression patterns correlated with the specific subtype of nodal T-cell lymphoma, such as angioimmunoblastic T-cell lymphoma (AILD), anaplastic large cell lymphoma (ALCL), and in peripheral T-cell lymphoma (PTCL), unspecified. In AILD, almost all cases were immunoreactive for OX40/CD134 (96%) and for CXCR3 (89%). In ALCL, all cases were immunonegative for OX40/CD134, and only a few cases (24%) were immunoreactive for CXCR3, whereas almost all cases (94%) were positive for ST2(L). Cases of PTCL, unspecified, were divided into 2 groups; group 1 (cases positive for either ST2(L), CCR5, or CXCR3) tended to show favorable prognosis compared with group 2 (cases negative for ST2(L), CCR5, and CXCR3). Our results indicate that further subtyping of PTCL, unspecified, into groups 1 and 2 could be significant for evaluating prognosis and understanding the functional role of these tumors.

Biomarkers, Tumor↗

Establishment of a new human malignant fibrous histiocytoma cell line, FU-MFH-1: cytogenetic characterization by comparative genomic hybridization and fluorescence in situ hybridization.

Although a number of malignant fibrous histiocytoma (MFH) cell lines have been reported, their characterization at a molecular cytogenetic level has not been fully established. In this study, we established a new human cell line, designated as FU-MFH-1, from a storiform-pleomorphic MFH arising in the retroperitoneum of a 61-year-old woman, and applied comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH) with chromosome painting probes for the characterization of chromosome alterations. FU-MFH-1 cells were spindle, round, or polygonal in shape with oval nuclei, and were maintained continuously in vitro for over 50 passages for more than 12 months. G-banding analysis was performed and FU-MFH-1 revealed a complex karyotype with an abnormal chromosome 19 containing a homogeneously staining region (hsr). CGH analysis showed a high-level amplification of 12q13-->q21. The high-level amplification detected by CGH was refined by FISH. These results showed that the hsr was composed of amplified DNA sequences from 12q. Our study emphasizes the usefulness of CGH as a powerful tool for chromosomal localization of amplified sequences. The FU-MFH-1 cell line should be useful for biologic and molecular pathogenetic investigations of human MFH.

Animals↗

Expressions of two adenomatous polyposis coli and E-cadherin proteins on human colorectal cancers.

Mutations in the adenomatous polyposis coli (APC) gene contribute to the progression of colorectal tumorigenesis. Despite the importance, few studies regarding the localization of this protein on surgically resected human colorectal cancer specimens using immunohistochemistry have been reported so far because of the unavailability of the antibodies for this use. The goal of this study has been to provide the APC protein expression and to validate the APC molecular studies. We took advantage of an immunohistochemistry procedure of applying the unique detergent-mediated antigen retrieval technique to frozen sections and examined the expressions of one amino (N)-terminal (AC4) and one carboxy (C)-terminal APC antibody (HG2). Further, we compared the stainings of APC antibodies with those of the E-cadherin antibody using a quantitative image analysis. E-cadherin is a critical morphogenetic regulator during embryogenesis and recent evidence strongly suggests that downregulation of E-cadherin expression in cancers is associated with a high rate of invasion and metastasis. The analysis indicated statistically that normal epithelia showed stronger staining than cancer cells ( P<0.05). Further, in normal epithelia, the amino (N)-terminal APC antibody (AC4) showed a positive correlation with another carboxy (C)-terminal APC antibody (HG2). E-cadherin showed no positive correlation with other APCs in either the normal epithelia or cancer cells. This study verified reduced expressions of APCs and E-cadherin proteins in colorectal cancer cells. This suggests that the normal APC and E-cadherin protein expressions in benign epithelium are progressively and independently lost in the sporadic colorectal cancers.

Adenomatous Polyposis Coli Protein↗

Expression of apoptosis-associated protein RCAS1 in macrophages of histiocytic necrotizing lymphadenitis.

Receptor-binding cancer antigen expressed on SiSo cells (RCAS1), which is recognized by the 22-1-1 monoclonal antibody (MoAb) against human uterine adenocarcinoma cell line SiSo, has been identified on various kinds of cancer cells. RCAS1 appears to be an apoptosis-associated protein that induces apoptosis in activated T-cells and erythroid progenitor cells. We previously demonstrated that monocytes/macrophages express RCAS1. In the present study, we investigated RCAS1 expression by 22-1-1 MoAb in histiocytic necrotizing lymphadenitis (HNL), which is characterized by necrotic lesions consisting of T-cells undergoing apoptosis and macrophages in proliferation. Expression of RCAS1 was analyzed by immunohistochemical staining in 9 cases of HNL and in 9 cases of reactive lymphadenitis used as a control. The ratio of RCAS1+ cells to CD68+ cells (monocytes/macrophages) was significantly higher in the patients with HNL than in the patients with reactive lymphadenitis (P = .0002; paired t test). Our findings suggest that RCAS1 expressed on macrophages may play an important role in the induction of activated T-cell apoptosis in cases of HNL.

Adolescent↗

Clinical and genetic characteristics of Japanese Burkitt lymphomas with or without leukemic presentation.

To clarify the clinical and genetic features of Burkitt lymphoma with or without leukemic presentation, we have conducted clinical, cytogenetic, and genetic studies. Of 40 Japanese patients with Burkitt lymphoma examined by cytogenetic and/or fluorescence in situ hybridization analysis or Southern blot analysis using MYC probes, 35 patients had t(8;14) translocations, and 5 had t(8;22). Breakpoints were located far upstream of MYC in 4 (12%) of 33 tumors with t(8;14), and Epstein-Barr virus infection was found in 3 (8%) of 40 tumors. These findings are similar to those reported for non-Japanese patients with the sporadic form of Burkitt lymphoma. Clinical and genetic characteristic were compared for 30 patients presenting with lymphoma and 10 presenting with leukemia. The overall survival was shorter in aggressively treated leukemia patients than in aggressively treated lymphoma patients (P = .003); however, the incidence rates of TP53 mutation, p16INK4a deletion, and p15INK4b deletion that were found in 6 (15%) of 40,3 (9%) of 35, and 2 (6%) of 35 tumors, respectively, were similar between the 2 subtypes. Thus, the present study has shown the different prognoses for the 2 subtypes of Burkitt lymphoma but has failed to clarify the genetic backgrounds that may explain the different outcomes.

Adolescent↗