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Biomedical subjects

R Ueda

Publications and source records attributed to R Ueda.

At least 199 records · Page 11Linked to original sources
PubMed1995

Differential expression of the c-kit proto-oncogene in germ cell tumours.

The c-kit proto-oncogene product and its ligand stem cell factor play an important role in haematopoiesis, spermatogenesis, and melanogenesis. Using an anti-c-kit antiserum raised against a synthetic peptide, we studied the immunohistochemical expression of the c-kit gene product in 60 germ cell tumours (GCTs) (53 testicular, 7 extragonadal), derived from primary GCTs in 45 cases and metastatic tumours in 15 cases. Twenty-eight out of 28 seminomas showed c-kit membranous staining in the majority of cells. A similar pattern of expression was seen in intratubular germ cell neoplasia. Nine out of 29 (32 per cent) non-seminomas displayed cytoplasmic, but not membranous, c-kit immunoreactivity in occasional cells. In three mixed GCTs, c-kit expression was limited to the seminoma component. In normal testis, c-kit expression was observed in some basal tubular cells, corresponding to undifferentiated spermatogonia. These results suggest a role for c-kit in the oncogenesis of GCT, where down-regulation of c-kit might be a critical step during progression from seminomas to non-seminomas. Immunohistochemical analysis of c-kit should be considered as a diagnostic aid for GCT and in particular may be helpful in the identification of certain extragonadal seminomas.

Adolescent↗
PubMed1995

Ki-1 (CD30) positive anaplastic large cell lymphoma of T-cell phenotype developing in association with long-standing tuberculous pyothorax: report of a case with detection of Epstein-Barr virus genome in the tumor cells.

We report a case of CD30 positive anaplastic large cell lymphoma of T-cell phenotype developing in association with long-standing tuberculous pyothorax. Phenotypic analysis showed CD1a-, CD2+, CD3+, CD4+, CD5-, CD8-, CD10-, CD19-, CD20 +/-, CD21-, CD25-, CD56-, T-cell receptor (TCR) alpha/beta antigens-, and HLA-DR+ phenotype. Neither rearrangement of TCR beta and gamma chain genes or of immunoglobulin heavy chain gene was detected in DNA extract from fresh material. The lymphoma cells were also shown to express the latent membrane protein-1 and the Epstein-Barr virus (EBV)-encoded nuclear antigen-2 by immunohistochemistry and EBV-encoded small RNAs by in situ hybridization.

Aged↗
PubMed1995

A 130 kDa polypeptide immunologically related to the 180 kDa catalytic subunit of DNA polymerase alpha-primase complex is detected in early embryos of Drosophila.

An immunocytochemical method using specific antibodies was employed to detect DNA polymerase alpha-primase complex in Drosophila melanogaster embryos during the first 13 nuclear division cycles. A monoclonal antibody specific to the 72 kDa polypeptide stained interphase nuclei, but not metaphase chromosome, while at late anaphase and thereafter staining of the chromosome was regained. On the other hand, a polyclonal antibody specific to the 180 kDa polypeptide stained not only the interphase nuclei but also the cytoplasmic regions surrounding interphase nuclei. These results suggest that the distributions of the 180 kDa and the 72 kDa polypeptides of DNA polymerase alpha-primase complex are different. We detected the 180 kDa and the 72 kDa polypeptides in the extract prepared from a single Drosophila embryo by Western blotting, and a 130 kDa polypeptide immunologically related to the 180 kDa polypeptide was also detected in the extract. These polypeptides (180, 130, and 72 kDa) in the embryos were detected at similar levels at interphase and at the mitotic phase. These three polypeptides were also detected in unfertilized eggs, showing that they were maternally stored. The 130 kDa polypeptide was detected till cycle 10, then began to decrease, and finally disappeared at cycle 14, whereas the 180 kDa and the 72 kDa polypeptides were present without marked fluctuation in quantity throughout the developmental stages. Even in unfertilized eggs, the level of the 130 kDa polypeptide decreased gradually with a similar time course to that in fertilized ones, but the levels of the 180 kDa and the 72 kDa polypeptides remained unchanged. This is the first report suggesting the existence of the 130 kDa polypeptide in vivo in the early embryos of Drosophila. The significance of the 130 kDa polypeptide is discussed.

Amino Acid Sequence↗
PubMed1995

The positive nuclear staining observed with monoclonal antibody against PRAD1/cyclin D1 correlates with mRNA expression in mantle cell lymphoma.

Recently, we produced a monoclonal antibody, 5D4, against the PRAD1/cyclin D1 product and suggested positive nuclear staining to be associated with mantle cell lymphoma (MCL). Now we have further characterized the specificity of this antibody and studied the relation of immunohistochemical detection to PRAD1/cyclin D1 mRNA expression and DNA rearrangement. Immunofluorescence and immunoblotting studies demonstrated the 5D4 antibody to be crossreactive with cyclin D2, but not cyclin D3. On immunostaining, 15 of 19 MCL cases (79%) presented the nuclear staining pattern and PRAD1/cyclin D1 mRNA expression was detected by Northern blot analysis in 12 of 15 MCL cases studied (80%): all cases with the mRNA expression showed the nuclear staining pattern. Southern blot analysis with 11q13 BCL-1 probes detected DNA rearrangements in 8 of 19 MCL cases (42%), all 8 exhibiting PRAD1/cyclin D1 mRNA expression. In 21 lymphoma cases of types other than MCL, neither the mRNA expression nor the nuclear staining were observed, although cytoplasmic staining was often apparent. These results indicated that positive nuclear staining of lymphoma cells by 5D4 antibody reflects PRAD1/cyclin D1 mRNA expression, and showed that this monoclonal antibody has diagnostic value for differentiating MCL from other types of lymphomas.

Animals↗
PubMed1995

Angioimmunoblastic T-cell lymphoma (angioimmunoblastic lymphadenopathy with dysproteinemia [AILD]-type T-cell lymphoma) followed by Hodgkin's disease associated with Epstein-Barr virus.

A patient is described with angioimmunoblastic T-cell lymphoma (AIL) (angioimmunoblastic lymphadenopathy with dysproteinemia [AILD]-type T-cell lymphoma), which was later followed by Hodgkin's disease. At the time of the initial diagnosis, histological examination of a cervical lymph node showed a typical picture of AIL with abundant clear cells which were CD45RO+, CD43+, and CD20-, and there was no evidence of a monoclonal B-cell proliferation by immunohistochemical analysis. In situ hybridization for Epstein-Barr virus (EBV) was negative. Interposed by a bout of recurrence, the patient developed, 16 years later, a left subparotid mass which showed histologic features of Hodgkin's disease, mixed cellularity type. Diagnostic Reed-Sternberg cells and their variants were CD30+, CD15- and CD20+. Neither rearrangement of TCR beta and gamma chain genes nor of immunoglobulin heavy chain and kappa light chain genes was detected in DNA extract from fresh material. In situ hybridization showed the presence of EBV within the Reed-Sternberg cells. The data show that EBV was not etiologically related to AIL in this case. Further, the deficit in cellular immunity that accompanied AIL conceivably permit primary EBV infection or reactivation of latent infection, which eventuated in development of Hodgkin's disease, but the exact pathogenesis remains uncertain.

Blotting, Southern↗
PubMed1995

Phenotypic and molecular characterization of croaker, a new mating behavior mutant of Drosophila melanogaster.

Mating of Drosophila melanogaster is a stereotypically patterned behavior consisting of a fixed sequence of actions that is primarily under genetic control. Although courtship can be easily monitored and quantified, little is known about its neural basis. To obtain a better understanding of cellular and molecular mechanisms underlying courtship, we have isolated mutants that disrupt specific aspects of mating behavior. The croaker mutant was isolated from approximately 1,000 lines harboring single P-element insertions by screening for aberrant courtship song: croaker males often generate polycyclic pulse song while most of the song pulses are monocyclic in the wild-type. The mutant is also defective in flight. Intracellular recordings of excitatory junction potentials from larval body wall muscles and Ca++ action potentials from adult indirect flight muscles demonstrated that neuromuscular transmission and Ca++ electrogenesis in the muscle fibers are not impaired by the croaker mutation. To define the croaker gene molecularly, genomic DNA surrounding the P-element insertion site was cloned by plasmid rescue and subsequent screening of a cosmid library. Northern blotting with the genomic DNA probes detected three transcripts in the wild-type, which were not expressed in the croaker mutant.

Animals↗
PubMed1995

Detection of hydroxyl radical in intact cells of Chlorella vulgaris.

Using ESR with 5,5-dimethyl-1-pyrroline N-oxide (DMPO) as a spin-trapping reagent, we measured the levels of free radical species generated from living cells of Chlorella vulgaris var. vulgails (IAM C-534). To investigate the production of free radicals in the living Chlorella vulgaris cells, the influence of DMPO toward the intact cells of the Chlorella vulgaris using the O2 evolution rate was first studied as a guide. Since the O2 evolution rate was not changed by DMPO, it was judged that DMPO has no toxicity toward the intact cells of Chlorella vulgaris. Only hydroxyl radicals (.OH) were detected as the DMPO-OH adduct in the suspension of intact cells of Chlorella vulgaris irradiated with visible light. Moreover, since production of .OH was inhibited by some hydroxyl radical scavengers such as KI and ethanol, production of .OH was proved to be due to hydroxyl radicals. It was also clear that the intensity of .OH increased with increasing irradiation intensity of visible light. Therefore, it was suggested that .OH might be one of the photoinhibition factors of the intact Chlorella vulgaris cells in severe light conditions.

Chlorella↗
PubMed1995

Bispecific antibody-mediated cytotoxicity by CD4+ and CD8(+)-activated T cells generated from leukemia patients after allogeneic bone marrow transplantation.

The F(ab')2 bispecific antibody (BSAb) was prepared from anti-CD3 moAb and anti-CD10 moAb. The BSAb could react with both CD3+ T cells and CD10+ leukemia cells and triggered T cell-mediated cytotoxicity. To apply the BSAb to prevention of leukemic relapse after BMT, we investigated the generation of both CD4+ and CD8+ anti-tumor effector T cells from patient's PBMC 14 days after BMT. Neither CD4+ T cells nor CD8+ T cells, which were activated with immobilized anti-CD3 moAb plus IL-2, could lyse CD10+ leukemia cells by themselves, but they showed augmented cytotoxicity against CD10+ leukemia cells by targeting with anti-CD3 x anti-CD10 BSAb. Moreover, the activated CD4+ T cells were demonstrated to produce IL-2 and IFN-gamma when they were cultured with CD10+ leukemia cells in the presence of the BSAb. The BSAb-mediated cytotoxicity of activated T cells was demonstrated not only against the recipient leukemia cells but also against third party leukemia cells. These results suggested that anti-CD3 x anti-CD10 BSAb might be a good tool to prevent relapse after BMT in combination with activated CD4+ T cells and CD8+ T cells.

Antibodies, Monoclonal↗
PubMed1995

[Molecular approach to lung cancer].

Lung cancer is associated with a number of cytogenetic abnormalities, such as chromosomal deletions on 3p, 12q, and 17p, which suggest the involvement of multiple tumor suppressor genes. These findings led to the discovery of the inactivation of the Rb and p53 genes in lung cancer. Recent remarkable progress in molecular biology should add a number of genes to the list of tumor suppressor gene involved in the pathogenesis of lung cancer. In addition, dominant oncogenes as well growth factors and their receptors have been shown to be involved in this process. Our understanding of the molecular pathogenesis of this fatal disease will now allow us to design new strategies to better diagnose and treat lung cancer. In this symposium, we discuss how the molecular oncological approach can be used to reduce the rapidly increasing rates of death due to lung cancer.

Genes, p53↗
PubMed1994

Immune function in mice lacking the perforin gene.

Mice lacking the perforin gene were generated by using targeted gene disruption in embryonal stem cells. When infected with lymphocytic choriomeningitis virus (LCMV), perforin-less (-/-) mice showed clear signs of having mounted an immune response based on activation of CD8 T cells but were unable to clear the LCMV infection. This failure to eliminate virus was accompanied by a failure to generate spleen cells capable of lysing LCMV-infected fibroblasts in vitro. Spleen cells from LCMV-infected -/- mice were able to lyse hematopoietic target cells after exposure to phorbol 12-myristate 13-acetate and ionomycin, provided the target cells expressed the Fas antigen. Spleen cells from -/- mice also responded to alloantigen in mixed leukocyte culture by blastogenesis and proliferation. The resulting cells were able to lyse hematopoietic target cells, although not as well as spleen cells from +/+ littermates sensitized in the same manner. However, lysis by -/- cells was again seen only if the target cells expressed Fas antigen. We conclude that perforin-less -/- mice retain and express the Fas lytic pathway as expressed in vitro but that this pathway is insufficient to clear an LCMV infection in vivo.

Animals↗
PubMed1994

A variant chromosome translocation at 11q13 identifying PRAD1/cyclin D1 as the BCL-1 gene.

The 11q13 breakpoint region of t(11;14) (q13;q32), translocated to the Ig heavy chain locus at 14q32, has been designated as BCL-1 for B-cell leukemia/lymphoma-1, but the nature of the transcriptional unit has long remained unclear. Recently, the PRAD1 gene encoding cyclin D1, isolated from the 11q13 region, was proposed as a candidate BCL-1 gene on the basis of chromosome walking and concordant overexpression of PRAD1 mRNA in cell lines with t(11;14)(q13;q32). We report here molecular analysis of a variant translocation at the BCL-1 locus, t(11;22)(q13;q11), showing juxtaposition of the Ig light chain gene, Ig lambda, to the PRAD1 gene at its 3' end, resulting in overexpression of PRAD1 mRNA. Because only the PRAD1 gene is present between the Ig heavy chain and light chain gene breakpoints, an identity between BCL-1 and the PRAD1/cyclin D1 gene is strongly indicated.

Base Sequence↗
PubMed1994

Serum glutathione S-transferase-pi level as a tumor marker for non-small cell lung cancer. Potential predictive value in chemotherapeutic response.

BACKGROUND: Resistance to chemotherapeutic agents is a major problem in non-small cell lung cancer (NSCLC) chemotherapy, and recent studies have indicated that glutathione S-transferase-pi (GST-pi) may play an important role in the resistance of cancer cells to alkylating agents that include platinum compound. METHODS: GST-pi in serum of 121 patients with NSCLC was measured by a sandwich enzyme-linked immunosorbent assay, and the serum concentrations of carcinoembryonic antigen (CEA), squamous cell carcinoma (SCC) antigen, and neuron-specific enolase (NSE) were also examined. Serum levels of these tumor markers were also evaluated in relation to therapeutic response in 69 patients who received combination chemotherapy with platinum compound. RESULTS: Fifty of 121 patients with NSCLC (41.3%) showed elevated serum GST-pi levels above a cutoff value of 34.8 ng/ml (mean + two standard deviations in 30 healthy control subjects). The positive rate of GST-pi in patients with NSCLC was higher than those of CEA (37.2%), SCC (15.7%), and NSE (14.9%). The mean pretreatment GST-pi level was significantly lower in patients with a partial response to chemotherapy than in those with no response (26.9 +/- 11.3 ng/ml versus 38.8 +/- 16.7 ng/ml; P < 0.003). Among patients with elevated levels of pretreatment serum GST-pi, only 13.8% (four of 29) responded to the combination chemotherapy, whereas partial response was observed in 40.0% of patients (16 of 40) with serum GST-pi concentration below the cutoff level (P < 0.02). Neither CEA, SCC, nor NSE showed such a relationship. CONCLUSIONS: The serum GST-pi level may have limited value as a tumor marker for NSCLC: Interestingly, pretreatment serum GST-pi levels may be a useful parameter for predicting therapeutic response to combination chemotherapy regimens that include platinum compound.

Adult↗
PubMed1994

Messenger RNA levels of five genes located at chromosome 11q13 in B-cell tumors with chromosome translocation t(11;14)(q13;q32).

To identify genes activated by chromosome translocation t(11;14)(q13;q32), mRNA levels of five genes (cyclin D1, EXP1, MB38, HST1, and INT2) at chromosome 11q13 were investigated. The cyclin D1 mRNA increased in BCL-1-rearranged B-cell tumor cell lines SP-49, NOP-2, FLAM-76, KMS-12-PE, and KMS-12-BM cells, while it was not detected in cell lines without the translocation, Raji, U266, and HEL cells. A significant amount of the MB38 mRNA was detected irrelevantly to the translocation in all of these cell lines. The mRNAs of EXP1, HST1, and INT2 were undetectable in these cells. The results suggested that the translocation activates cyclin D1 alone, while the mRNA levels of the other four genes are regulated independently of the translocation.

Blotting, Northern↗
PubMed1994

Ectopic expression of c-kit in small-cell lung cancer.

Accumulating evidence suggests that c-kit plays an important role in the regulation of growth of at least 3 lineages of stem cells, while only very limited data are available on the development of human solid tumors. Our recent studies have shown that c-kit transcripts are expressed in a very restricted sub-set of human solid tumors such as small-cell lung cancer (SCLC). We have also conducted an immunohistological study on in situ localization of the c-kit protein in various human solid tumors as well as in corresponding fetal and adult normal tissues. No c-kit expression was detected in normal bronchial epithelial cells or pneumocytes in lung parenchyma of human fetal and adult specimens, indicating that the c-kit protein is aberrantly expressed in lung-cancer cells. We also found that significant chemotactic response as well as moderate in vitro cell growth occurred in SCLC cell lines upon addition of recombinant human stem-cell factor.

Adenocarcinoma↗
PubMed1994

Newly established cell lines from Drosophila larval CNS express neural specific characteristics.

From the central nervous system of Drosophila melanogaster 3rd instar larvae, eight continuous cell lines have been established (named ML-DmBG1 to 8). Using ML-DmBG2, single colony isolation was carried out and six colonial clones were obtained. All reacted to the antibody to horseradish peroxidase, which is a neuronal marker in insects. Acetylcholine, a known neurotransmitter in Drosophila, was detected in three of the colonial clones by high performance liquid chromatography. Therefore, it is concluded that the established colonial clones are neural cells originating in the larval central nervous system. Among them, some variation was observed with respect to morphology, acetylcholine content, and reactivity to anti-HRP. The variation may reflect the heterogeneity of cells composing the central nervous system.

Acetylcholine↗
PubMed1994

A case of neural cell adhesion molecule-positive peripheral T-cell lymphoma associated with human T-cell lymphotrophic virus type 1 showing an unusual involvement of the gastrointestinal tract during the course of the disease.

We report a case of neural cell adhesion molecule (NCAM)-positive peripheral T-cell lymphoma (PTCL), pleomorphic, medium and large cell type according to the updated Kiel classification, which was associated with human T-cell lymphotrophic virus type 1 (HTLV-1). The patient showed an unusual involvement of the gastrointestinal tract forming a bulky mass during the course of his disease, and a relatively indolent clinical course for 53 months until death. Phenotypic analysis showed CD2+, CD3-, CD4+, CD5+, CD7+, CD8-, CD16-, CD56+, and CD57- phenotype. Human T-cell lymphotrophic virus type 1 antibody was detected by the enzyme-linked immunosorbent assay. The proviral integration of HTLV-1 and the monoclonal rearrangements of T-cell receptor beta and gamma genes also were confirmed in DNA extract from fresh material. This fact calls attention to NCAM as one of the potential factors playing a role in the localization and behavior of lymphomas even within the category of PTCL associated with HTLV-1, ie, adult T-cell leukemia/lymphoma (ATLL).

Antigens, Surface↗