Publications (11)29.74 Total impact

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    ABSTRACT: Cytotoxic effects of normal mouse serum on mouse tumor cells were investigated in vitro. When FE melanoma cells of C57BL/6 mouse origin, were cultured in medium containing 1% fetal calf serum (FCS) and 10-30% C57BL/6 mouse serum, number of viable FE cells markedly decreased after a little increase in their number, indicating cell death of FE cells in culture with mouse serum. Phase-contrast microscopic examination showed appearance of fatty degeneration in FE cells after 24 h, and an increase in cell death after 48 h. Electron microscopic examination, and agarose gel electrophoresis of DNA at 72 h of culture showed that their cell death occurred as necrosis. This cytotoxic effect of mouse serum was also found in culture of combinations of C57BL/6 mouse serum and C57BL/6 mouse melanoma cells (G6 cells), and BALB/c mouse serum and various BALB/c mouse tumor cells (G-5 and G-1 liver tumor cells, and Colon 26 cells). Furthermore, sera of BALB/c and B10D2 mice also showed the cytotoxic effect on FE cells. The cytotoxic effect of mouse serum was not ascribed to complement activity because all mouse sera were treated at 56 degrees C for 30 min before use, and this heat treatment completely abolished complement activity, and because serum of C5-deficient mice also showed the cytotoxic effect. This cytotoxic activity was stable at heat treatment at 100 degrees C for 10 min, and was in a serum fraction of molecular weights more than 30,000 dalton. The present results show that normal mouse serum has a factor(s) inducing fatty degeneration and necrosis of mouse tumor cells.
    Oncology Reports 05/1998; 5(3):693-8. DOI:10.3892/or.5.3.693 · 2.30 Impact Factor
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    ABSTRACT: The effect of pregnancy on experimental pulmonary metastasis was studied. Compared to the incidence of pulmonary metastasis induced by G6 cells in non-pregnant mice, the incidence of such metastasis was found to be greatly enhanced when the cells were injected i.v. in the latter half of pregnancy. The maximum enhancement was seen on the 15th day of pregnancy. The incidence of pulmonary metastasis returned to the level observed in non-pregnant mice when the cells were injected 4 days after parturition. Pregnancy also significantly increased the incidence of pulmonary metastasis of 2 other cell lines (3LL and Colon 26). Injection of G6 cells after hysterectomy performed on the 15th day of pregnancy resulted in decreased lung colonization, similar to that seen after parturition. Quantificative analysis of the arrest of G6 cells labeled with [125I]-5-iodo-2'-deoxyuridine in the lungs showed that the tumor-cell clearance from the lungs during the 24-72 hr after tumor-cell injection was much slower in pregnant than in non-pregnant mice. The continuous administration of beta-estradiol and/or progesterone, which maintained serum levels of the hormones equivalent to those prevailing on the 15th day of pregnancy, did not affect the lung colonization of G6 cells. Tumor-cell-platelet aggregation was more extensive with platelets obtained from mice at the 15th day of pregnancy than with those from non-pregnant mice. When platelets isolated from pregnant mice were injected into normal mice 5 min before G6 injection, lung metastasis was also enhanced. These findings suggest that a pregnant host is handicapped with regard to pulmonary metastasis, this being partly due to increased platelet-aggregating activity in response to tumor cells.
    International Journal of Cancer 07/1995; 62(3):314-8. DOI:10.1002/ijc.2910620314 · 5.09 Impact Factor
  • Y Tanigaki · Y Saeki · T Matsuhisa · S Ishiguro · Y Mori · H Tanaka · H Akedo
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    ABSTRACT: Two cell lines were established from liver cells (BALB/c mouse) exposed to benzo(a)pyrene: one was highly metastatic (G-5) and the other poorly metastatic (G-1) to the lung when subcutaneously implanted. However, there was no difference in lung colonization between G-1 and G-5 cells when they were intravenously injected. When G-1 cells were subcutaneously inoculated on one side of the back of mice followed by a challenge on the other side with G-5 cells 10 days later, the growth of the latter tumor was inhibited and the number of metastatic nodules in the lung was reduced. The functional vascular volume of G-1 tumor was less than the G-5 one. In mice bearing G-1 tumors, the neovascularization of intradermally inoculated G-5 cells was reduced. The conditioned medium from G-1 culture contained an inhibitory activity on the growth of endothelial cells from calf pulmonary artery. The inhibitory substance(s) was heat-stable, trichloroacetic acid-soluble, nondialyzable and resistant to various proteinases. The present results imply that G-1 cells produce an antiangiogenic substance(s), probably a polysaccharide(s), which inhibits the angiogenesis required for growth and metastasis of the G-5 tumor.
    Invasion and Metastasis 02/1995; 15(1-2):70-80.
  • Yoichi Mori · Yumiko Tanigaki · Atsuko Yamaguchi · Hitoshi Akedo
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    ABSTRACT: The effect of sodium butyrate on the intracellular cyclic AMP levels and the activities of cyclic AMP-regulating enzymes were examined in two types of mastocytoma p-815 cells in culture: one type (S cell) was sensitive and the other (R cell) was resistant to the induction of differentiation by sodium butyrate. In the presence of sodium butyrate, adenylate cyclase activity increased in both S and R cells to the same degree, whereas the level of cyclic AMP was elevated only in S cells. Cyclic AMP phosphodiesterase activity increased in R cells but not in S cells. Cyclic AMP phosphodiesterase activities of two cell populations differed in their response to sodium butyrate and they seem to have an important role in regulating cellular level of cyclic AMP that might be an important factor in controlling cell differentiation.
    Biochemical and Biophysical Research Communications 09/1986; 138(3):1030-6. DOI:10.1016/S0006-291X(86)80385-0 · 2.30 Impact Factor
  • Y Mori · H Akedo · T Matsuhisa · Y Tanigaki · M Okada
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    ABSTRACT: Microtubule poisons such as colchicine, colcemid and vinblastine caused extrusion of nuclei of murine suspension culture cells (mastocytoma p-815 cells, myeloma PU-3 cells, leukemia M1 cells). Enucleation did not follow spontaneously in most cells, but it did occur when the treated cells were centrifuged in Separate-L gradient. These poisons did not induce nuclear extrusion in cells growing in monolayer (L cells, BALB/c 3T3 cells, SV40-transformed BALB/c 3T3 cells, histiocytoma HC-11 cells). Cytochalasin B (CB) that had been reported to cause nuclear extrusion in the cells cultured in monolayer [1] did not induce the extrusion in the suspension culture cells but inhibited the colchicine-induced nuclear extrusion.
    Experimental Cell Research 09/1984; 153(2):574-80. DOI:10.1016/0014-4827(84)90628-1 · 3.25 Impact Factor
  • Y Mori · Y Tanigaki · K Shinkai · M Okada · H Akedo
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    ABSTRACT: Alkaline phosphatase (ALP) activity of cultured Li-10 cells obtained from rat liver was found to be a function of cell population density. After the cells grew to confluence, the enzyme activity per cell increased about 100 times that at a low population density. The increase of activity was inhibited by the addition of actinomycin D or cycloheximide to the culture medium. When the cells that had gained high ALP activity after confluency were subcultured, ALP activity decreased to a low basal level after about 48 h. Under cytochemical examination using an electron microscope, the induced ALP activity was seen exclusively at the apical surface region of the cells but scarcely at cell-cell and cell-substratum contact regions.
    European Journal of Cell Biology 03/1982; 26(2):255-8. · 3.83 Impact Factor
  • Y Mori · H Akedo · Y Tanigaki · K M Tanaka · M Okada · N Nakamura
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    ABSTRACT: Effect of sodium butyrate on the cellular serotonin, histamine and glycosaminoglycans (GAGs) contents of mastocytoma p-815 cells was examined. When mastocytoma p-815-4 cells were cultured for 4 days in the presence of butyrate at 2 mM, the optimal concentration for the induction of granulopoiesis in this cell line, the cellular serotonin, histamine and GAGs contents increased markedly: serotonin increased almost 7 times, histamine 140 times and total GAGs 10 times. Chondroitinase ABC-resistant GAGs, heparin and/or heparan sulfate, increased 21 times. These cellular products reached at 3 or 4 days culture their maximal levels which depended on the amount of butyrate added up to 2 mM. The effectiveness of butyrate varied among the cloned cell lines: serotonin and histamine contents did not increase in mastocytoma p-815-6 cells, in which butyrate failed to induce granulopoiesis.
    Experimental Cell Research 07/1980; 127(2):465-70. DOI:10.1016/0014-4827(80)90455-3 · 3.25 Impact Factor
  • Y Mori · H Akedo · Y Tanigaki · K Tanaka · M Okada
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    ABSTRACT: Cilia developed on the surfaces of cells of an established line derived from rat liver (LI 10) as the population of the cultures increased. Ultrastructural examination by the scanning electron microscope (SEM) showed that a cilium appeared on a cell surface when cells were cultured more than 5 days after reaching the confluent stage. The essential components of the cilium were a basal body and central and peripheral fibrils displaying 9 + 2 or 9 + 0 doublet arrangement in the cross section. The cilium was not observed during the time when the cells were growing.
    Experimental Cell Research 06/1979; 120(2):435-9. DOI:10.1016/0014-4827(79)90408-7 · 3.25 Impact Factor
  • Y Mori · H Akedo · K Tanaka · Y Tanigaki · M Okada
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    ABSTRACT: The effect of sodium butyrate on mastocytoma p-815-4 cells was examined. In the presence of butyrate, the proliferation of mastocytoma p-815-4 cells decreased without any detectable cellular degeneration, and the average cell volume of the butyrate-treated cells increased. These cells tended to adhere to the substratum, and manifested their morphological changes. On the second day after the addition of butyrate, basophilic granules appeared around the Golgi area and gradually increased in number and in size. Ultrastructural examination with the electron microscope showed a well developed Golgi complex, numerous basophilic granules, many profiles of endoplasmic reticulum and many microvilli. These changes were maximized 3–4 days after the addition of this agent. The agglutination of the butyrate-treated cells by concanavalin A (ConA) or wheat germ agglutinin (WGA) did not change significantly. The induction of granulopoiesis of the cells in the presence of butyrate was prevented by the addition of actinomycin D or cycloheximide.
    Experimental Cell Research 02/1979; 118(1):15-22. DOI:10.1016/0014-4827(79)90578-0 · 3.25 Impact Factor
  • Y Mori · H Akedo · Y Tanigaki
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    ABSTRACT: In the presence of concanavalin A obtained from nata beans (Canavalia gladiata), mastocytoma cells, Ogun, HR-1, Janosky and monocytic leukemia cells in suspension culture rapidly adhered to the glass surface and gradually spread their cytoplasms like monolayer cells. The morphological shape of the spreading cells differed according to cell strains. The spreading cells were not detached by the treatment with trypsin or with EDTA. Actinomycin D and cycloheximide did not affect either the adhesion or the spreading of mastocytoma cells. Colchicine inhibited the adhesion of mastocytoma cells only slightly but it caused a great change in the morphological shape of the spreading cells. The cell adhesion was temperature-dependent and was inhibited markedly by d-mannose and α-methyl-d-glucoside and slightly by d-galactose.
    Experimental Cell Research 05/1973; 78(2):360-6. DOI:10.1016/0014-4827(73)90080-3 · 3.25 Impact Factor
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    ABSTRACT: Concanavalin A was purified and crystallized from Canavalia gladiata. The crystallized concanavalin A possessed properties similar in biological respects to those from Canavalia ensiformis. However, their physicochemical properties differed slightly from each other. Concanavalin A from Canavalia gladiata agglutinates various types of animal cells and stimulates blast formation of human and rat peripheral lymphocytes. On isoelectric focusing in polyacrylamide gel concanavalin A was separated into eight protein bands. From rat erythrocyte stroma two glycoproteins which were agglutinated by concanavalin A were isolated and purified. The molecular weights of these proteins were estimated as 2 · 105 and 3 · 105, respectively. Both of the glycoproteins contained a relatively large amount of hexose and a small quantity of sialic acid. No hexosamine was detected.
    Biochimica et Biophysica Acta (BBA) - Protein Structure 07/1972; 271(2-271):378-387. DOI:10.1016/0005-2795(72)90213-9