The Tohoku Journal of Experimental Medicine
Online ISSN : 1349-3329
Print ISSN : 0040-8727
ISSN-L : 0040-8727
Volume 168 , Issue 2
Showing 1-50 articles out of 61 articles from the selected issue
  • FRANK J. GONZALEZ, CHARLES L. CRESPI, MACEIJ CZERWINSKI, HARRY V. GELB ...
    1992 Volume 168 Issue 2 Pages 67-72
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    GONZALEZ, F.J., CRESPI, C.L., CZERWINSKI, M. and GELBOIN, H.V. Analysis of Human Cytochrome P450 Catalytic Activities and Expression. Tohoku J. Exp. Med., 1992, 168 (2), 67-72 - Cytochromes P450 are a large group of membrane- associated heme protein monooxygenases, most of which are responsible for metabolizing foreign compounds. Chemical carcinogens, which are ingested or absorbed into the body as inert forms, are metabolically activated by P450s to electrophilic metabolites capable of binding to and mutating DNA. Different P450 forms are responsible for activation of the various classes of chemical carcinogens including the arylamines, polycyclic aromatic hydrocarbons, nitrosamines and aflatoxins. Thus, the cellular constituency and levels of P450s could determine the fate of a particular carcinogen and the risk of humans to exposure. To study the catalytic activities of human P450s, human P450 cDNAs were cloned and expressed into active enzymes using cultured cells. By both transient and stable cDNA expression systems, several human P450s were found to be capable of metabolically-activating the human hepatocarcinogen afiatoxin B1. These cDNA expression systems can also be used to determine whether an unknown chemical will be activated by a human P450 and thus be toxic or mutagenic in humans. To assess the extent of interindividual variation in P450 expression, probes developed from P450 cDNAs are being used to quantify levels of P450 mRNAs in various human tissues. Studies using RNase protection revealed that the closely related CYP2B6 and CYP2B7 mRNAs could be independently quantified in liver and lung, respectively. This procedure can be used to examine expression of different P450 genes in banks of human tissue specimens. - human cytochrome P-450; catalytic activity; cDNA expression; chemical carcinogen; RNase protection
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  • C.R. WOLF, C.A.D. SMITH, G. SMITH, A.C. GOUGH, S. BRYANT, N.K. SPURR, ...
    1992 Volume 168 Issue 2 Pages 73-81
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    WOLF, C.R., SMITH, C.A.D., SMITH, G., DOUGH, A.C., BRYANT, S., SPURR, N.K. and HARRISON, D.J. Molecular Genetics of the Human Cytochrome P450- Dependent Monooxygenases. Tohoku J. Exp. Med., 1992, 168 (2), 73-81 - In this work, the role of genetic as well as environmental factors in determining cytochrome P450 isozyme levels in man have been studied. Simple DNA based assays for the identification of individuals nulled at the CYP2D6 locus are described and have been applied to investigate whether this gene defect is associated with altered cancer susceptibility. In contrast to literature reports, in no cancer type were poor metabolizers underrepresented, indeed in several cancers the mutant allele frequency was increased. A model using human tumours grown as xenografts is described that should help elucidate the factors which regulate P450 levels in man. - human cytochrome P-450; cancer susceptibility; mutant allele frequency; CYP2D6; human tumor xenograft
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  • ALAN POLAND, CHRISTOPHER BRADFIELD
    1992 Volume 168 Issue 2 Pages 83-87
    Published: 1992
    Released: August 31, 2006
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    POLAND, A, and BRADFIELD, C. A Brief Review of the Ah Locus. Tohoku J. Exp. Med., 1992, 168 (2), 83-87 - The Ah locus, first described as a functional polymorphism among inbred strains of mice, encodes the Ah receptor-a ligand dependent transcriptional activator. This paper reviews the work on the Ah receptor and its importance in the expression of cytochrome P-450IA1 and the pleiotropic effects of halogenated aromatic hydrocarbons. - Ah locus; Ah receptor; cytochrome P-450IA1; halogeneted aromatic hydrocarbons
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  • TETSUYA KAMATAKI, MITSUKAZU KITADA, MASAYUKI KOMORI, TSUYOSHI YOKOI, R ...
    1992 Volume 168 Issue 2 Pages 89-95
    Published: 1992
    Released: August 31, 2006
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    KAMATAKI, T., KITADA, M., KOMORI, M., YOKOI, T. and KITAMURA, R. Human Fetal Liver Cytochrome P-450: Capacity to Form Genotoxic Metabolites. Tohoku J. Exp. Med., 1992, 168 (2), 89-95 - Unlike most experimental animals, human fetal liver possesses forms of cytochrome P-450. Thus, the purpose of this study was to clarify the toxicological significance of these forms of cytochrome P-450 to understand possibile roles of these cytochromes in producing genotoxic metabolites from promutagens. In fact, human fetal livers showed considerable capacity to activate aflatoxin B1 and IQ (2-amino-3-methylimidazo [4, 5-f] quinoline). Three of four forms of cytochrome P-450, P-454HFLa-d, which we could purify from human fetal livers were capable of activating promutagens to mutagens. One of these three forms, namely P-450HFLa, catalyzed the metabolic activation of aflatoxin B1 and IQ. An expression plasmid containing HFL33 cDNA encoding P-450HFLa was constructed and the protein expressed in insect (Sf9) cells and in human cancer cells, MCF-7. Aflatoxin B1 was efficiently activated to a mutagen upon addition of the lysate of Sf9 cells to the incubation mixture for the assay. Transformants of MCF-7 cells expressing P-450IIIA7 (HFLa) showed higher sensitivity to aflatoxin B1 than the parental MCF-7 cells as detected by cytotoxicity. - human fetal liver cytochrome P-450; genotoxic metabolites; aflatoxin B1; 2-amino-3-methylimidazo [4, 5-f] quinoline (IQ); transformation of MCF-7 cells
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  • KIYOMI SATO, KIMIHIKO SATOH, SHIGEKI TSUCHIDA, ICHIRO HATAYAMA, HONGXI ...
    1992 Volume 168 Issue 2 Pages 97-103
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    SATO, K., SATOH, K., TSUCHIDA, S., HATAYAMA, I., SHEN, H., YOKOYAMA, Y., YAMADA, Y. and TAMAI, K. Specific Expression of Glutathione S-transferase Pi Forms in (Pre)neoplastic Tissues: Their Properties and Functions. Tohoku J. Exp. Med., 1992, 168 (2), 97-103 - The detection of preneoplastic cells is very important for the analysis of carcinogenic processes and for developing strategies for prevention and treatment of cancer. We have been investigating enzyme alterations occurring during rat chemical hepatocarcinogenesis, especially to find more specific enzyme markers for preneoplastic hepatic lesions. We identified the placental form of glutathione S-transferese (GST-P; GST 7-7) as a new marker enzyme for preneoplastic hepatocytes. We also found human placental form, GST-π, to be a possible tumor marker for various human tissues except liver. In this article, their properties and possible functions are reviewed on basis of our recent investigations. A peroxisomal enzyme, enoyl CoA hydratese, in also described as a possible negative marker for rat preneoplastic hepatic foci/nodules and hepatomas induced by peroxisome proliferators. - (pre)neoplastic marker; glutathione S-transferase; peroxisome proliferator; enoyl CoA hydratase
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  • NAOYUKI TANIGUCHI, MUTSUO ISHIKAWA, TETSUO KAWAGUCHI, JUNICHI FUJII, T ...
    1992 Volume 168 Issue 2 Pages 105-111
    Published: 1992
    Released: August 31, 2006
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    TANIGUCHI, N., ISHIKAWA, M., KAWAGUCHI, T., FUJII, J., SUZUKI, K. and NAKATA, T. Expression on Mn-Superoxide Dismutase in Carcinogenesis. Tohoku J. Exp. Med., 1992, 168 (2), 105-111 - Human liver manganese superoxide dismutase (Mn-SOD) was highly purified by a simple procedure and crystallized. A monoclonal antibody against Mn-SOD, whose antigen-binding epitope is a C-terminus peptide was developed. Using this antibody, an enzyme-linked immunosorbent assay (ELISA) was developed. We found that Mn-SOD is highly expressed in human ovarian cancer and the serum level of the enzyme is a useful marker for the diagnosis and monitoring of the epithelial type of ovarian cancer. Tumor necrosis factor-α (TNF), lipopolysaccharide, IL-1 and phorbol ester induced the m-RNA of Mn-SOD as well as protein levels in TNF-resistant cells. No such induction was observed in Cu, Zn-SOD. Studies on the induction mechanisms indicated that at least two separate signal-transducing pathways are involved in expression of the Mn-SOD gene. One is triggered by protein kinase C activation itself in the absence of new protein synthesis. The other can be activated by stimulations with various cytokines in which a protein factor that can be induced by phorbol ester treatments is involved. - Mu-superoxide dismutase; monoclonal antibody; epithelial ovarian cancer; Tumor necrosis factor, phorbol ester
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  • FUMIYUKI VEMATSU, HIDEAKI KIKUCHI, MASAKICHI MOTOMIYA, TATSUYA ABE, CH ...
    1992 Volume 168 Issue 2 Pages 113-117
    Published: 1992
    Released: August 31, 2006
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    UEMATSU, F., KIKUCHI, H., MOTOMIYA, M., ABE, T., ISHIOKA, C., KANAMARU, R., SAGAMI, I. and WATANABE, M. Human Cytochrome P450IIE1 Gene: DraI Polymorphism and Susceptibility to Cancer. Tohoku J. Exp. Med., 1992, 168 (2), 113-117 - Human cytochrome P450IIE1(CYP2E) is involved in the metabolic activation of procarcinogens such as N-nitrosodimethylamine, benzene and ethyl carbamate. We screened DNA from 28 individuals for restriction fragment length polymorphisms (RFLPs) is the human P450IIE1 gene and detected an RFLP for the restriction endonuclease DraI. The distribution of the genotypes of this polymorphism among lung cancer patients (n=74) differed from that among controls (n=73) with statistical significance of p<0.05. In addition, the distribution among patients with cancers of the digestive system (n=38) was also different from that among controls. Our findings indicate an association between the DraI polymorphism of the IIE1 gene and susceptibility to cancers of the lung and the digestive system, - human cytochrome P450IIE1 gene; DraI polymorphism; susceptibility to cancer; lung cancer; cancers of the digestive system
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  • TAKEMI KINOUCHI, KEIKO KATAOKA, KOICHI MIYANISHI, SHIGERU AKIMOTO, YOS ...
    1992 Volume 168 Issue 2 Pages 119-122
    Published: 1992
    Released: August 31, 2006
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    KINOUCHI, T., KATAOKA, K., MIYANISHI, K., AKIMOTO, S. and OHNISHI, Y. Role of Intestinal Microflora in Metabolism of Glutathione Conjugates of 1- Nitropyrene 4, 5-Oxide and 1-Nitropyrene 9, 10-Oxide. Tohoku J. Exp. Med., 1992, 168 (2), 119-122 - DNA adduct formation in the liver of B6C3F1 mice after administration of 1-nitropyrene (1-NP) was shown by the 32P-postlabeling technique. The major adduct was not N-(deoxyguanosin-8-yl)-1-aminopyrene, which was easily formed in in vitro nitroreduction of 1-NP in the presence of DNA, but the major spots migrated to the same position as the in vitro DNA adduct spots of K-region epoxides of 1-NP (1-NP 4, 5- and 9, 10-oxide). 1-NP oxides formed by the oxidative activation of 1-NP in the liver were excreted into the bile as detoxified glutathione conjugates which were changed to cysteine conjugates in the upper intestinal tract. The cysteine conjugates were degraded by cysteine conjugate β-lyase (β-lyase) of intestinal microflora in the lower intestinal tract. The mutagenicity of cysteine conjugates of 1-NP oxides for Salmonella typhimurium was enhanced by addition of β-lyase and was decreased by addition of aminooxyacetic acid, a β-lyase inhibitor. The in vitro binding of the cysteine conjugates to calf thymus DNA was increased by addition of β-lyase and xanthine oxidase. We administered glutathione conjugates of 1-NP oxides to two groups of mice that had been treated with antibiotics or saline by gavage and analyzed the DNA adducts in the lower intestinal mucosa. The specific DNA adducts were detected in the saline-treated group but not in the antibiotics-treated group. These results suggest that intestinal microflora play an important role in activation of glutathione conjugates of 1-NP oxides. - intestinal microflora; glutathione conjugates; 1-nitropyrene 4, 5-oxide, 1-nitropyrene 9, 10-oxide; cysteine conjugate β-lyase; DNA adduct formation
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  • MASAYUKI NUMATA, HIROAKI HATA, HIROKO TOHDA, AKIRA YASUI, ATSUSHI OIKA ...
    1992 Volume 168 Issue 2 Pages 123-128
    Published: 1992
    Released: August 31, 2006
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    NUMATA, M., HATA, H., TOHDA, H., YASUI, A and OIKAWA, A. DNA Repair Pathways in Mammalian Cells Analyzed by Isolation of ACNU-Sensitive Chinese Hamster Ovary Cells. Tohoku J. Exp. Med., 1992, 168 (2), 123-128 - 1-[(4- amino-2-methyl-5-pyrimidinyl)methyl]-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) causes chloroethylation of DNA strand followed by cross linking through an ethylene bridge. We recently isolated two ACNU sensitive mutants from mutagenized Chinese hamster ovary cells, and found them to be new drug sensitive recessive mutansts (Hata et al. 1991). The O6-methyl guanine DNA methyl transferase (MT) activities of these cells were undetectable as the parental cell line, indicating that the sensitivity of the mutant cell lines to ACNU was not due to the decreased cellular level of this enzyme. By complementation analysis with the 7 established UV-sensitive CHO cell lines, one of the mutants, UVS1, turned out to complement their UV-sensitivity and, therefore, build a new complementation group among all the CHO cell lines ever reported. The other mutant, CNU1 showed hypersensitivity only to chloroethylating agents (ACNU, CCNU) and exhibited a slightly reduced unscheduled DNA synthesis (UDS) induced by UV. It is, therefore, suggestive that this mutant is defective in a specific step of DNA repair systems, which is important for the processing of DNA damages produced by ACNU. Only cell lines from the complementation group 1 and 4 out of 7 established complementation groups of UV-sensitive CHO mutants were more sensitive to ACNU than UVS1 and CNU1, indicating some steps of excision repair pathways as well as specific repair system play important roles in repairing ACNU-induced DNA damages. - chloroethylating agent; ACNU; cross linking; DNA repair; CHO mutant
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  • HIROKO TOHDA, JI HE ZHAO, ATSUSHI OIKAWA
    1992 Volume 168 Issue 2 Pages 129-132
    Published: 1992
    Released: August 31, 2006
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    TOHDA, H., ZHAO, J.H. and OIKAWA, A. A Possible Involvement of DNA Topoisomerase I in “Caffeine Effect” after Ultraviolet Irradiation. Tohoku J. Exp. Med., 1992, 168 (2), 129-132 - Caffeine has been known to enhance lethal and chromosome damaging effects of chemical and physical mutagens. In spite of numerous investigations, the mechanism is not fully elucidated. In this paper, we describe that 1) post-treatment with camptothecin (CPT), a specific inhibitor of DNA topoisomerase (topo) I, enhances SCE-induction by ultraviolet light (UV), as post-UV caffeine treatment does, 2) the lethal effect of UV is also enhanced but to a lesser degree than by post-UV caffeine treatment, and 3) caffeine, like CPT, inhibits calf thymus topo I activity, as determined by relaxation of pBR322 supercoiled DNA. These results suggest that the mechanism(s) of lethal and SCE enhancement involves the ability of caffeine to inhibit topo I. - caffeine; camptothecin; topoisomerase I; UV-damage repair
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  • MARI SEMBA, NAOMICHI INUI, MASA-ATSU YAMADA
    1992 Volume 168 Issue 2 Pages 133-136
    Published: 1992
    Released: August 31, 2006
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    SEMBA, M., INUI, N. and YAMADA, M. Inhibitory Effects of Antipromoters and Radical Scavengers on the Promotion Process in Two-Stage Cell Transformation. Tohoku J. Exp. Med., 1992, 168 (2), 133-136 - To find the mechanism of promotion process, we have investigated the antipromoting effects of radical scavengers and specific inhibitors for phospholipid metabolism and for protein kinase C using a two-stage transformation assay system in BALB/3T3 cells. All radical scavengers and inhibitors tested showed the antipromoting effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)-promoted transformation. Diacylglycerols, activators of protein kinase C, showed promoting effects in vitro and the promoted-transformation by them was suppressed by radical scavengers employed. By an electron spin resonance (ESR) spin-trapping method, inhibitors, which suppressed promoted-transformation by TPA markedly, had •OH scavenging action. It was found using a ESR spin-trapping method that treatment of TPA on BALB/3T3 cells generates •OH in a dose-dependent manner. These results suggest that generation of oxygen radicals, especially •OH, which occurs in the processes of phospholipid metabolism as well as activation of protein kinase C, is essential to the promotion process. - two-stage cell transformation; oxygen radicals; a promotion process; BALB/3T3 cells
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  • MASAYUKI ITANO, SEI MORITA, HIROMI FUJIE, YOSHIYUKI OHASHI, NAOKO MINE ...
    1992 Volume 168 Issue 2 Pages 137-139
    Published: 1992
    Released: August 31, 2006
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    ITANO, M., MORITA, S., FUJIE, H., OHASHI, Y., MINEGISHI, N., MINEGISHI, M., YAMAGUCHI, Y., SATO, T., TSUCHIYA, S., KONNO, T., HAYASHI, Y., OHI, R. and SHIRAISHI, H. Mass Screening for Neuroblastoma in Miyagi Prefecture. Tohoku J. Exp. Med., 1992, 168 (2), 137-139 - In Japan, aiming at early and preclinical detection of neuroblastoma in infancy a mass screening program for the tumor has been implemented nationwide using urinary tests for catecholamine metabolites, vanillylmandelic acid (VMA) and homovanillic acid (HVA) (Sawada 1990; Sawada et al. 1991). In this report, the results obtained from the screening program in Miyagi Prefecture for the last 6 years are described. The detection rate of neuroblastoma by mass screening was 1:8, 377 among 125, 652 infants tested in Miyagi Prefecture. All but one patients survived after removal of the primary tumor and none or minimal chemotherapy. - neuroblastoma; mass screening; urine VMA; urine HVA
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  • YUSUKE NAKAMURA, ISAMU NISHISHO, KENNETH W. KINZLER, BERT VOGELSTEIN, ...
    1992 Volume 168 Issue 2 Pages 141-147
    Published: 1992
    Released: August 31, 2006
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    NAKAMURA, Y., NISHINO, I., KINZLER, K.W., VOGELSTEIN, B., MIYOSHI, Y., MIKI, Y., ANDO, H. and HORII, A. Mutations of the APC (Adenomatous Polyposis Coli) Gene in PAP (Familial Polyposis Coli) Patients and in Sporadic Colorectal Tumors. Tohoku J. Exp. Med., 1992, 168 (2), 141-147 - We have isolated several genes on chromosome 5q21 region tightly linked to hereditary familial polyposis coli (FAP) and Gardner's syndrome (GS). Two of these genes (MCC and APC) were found to be somatically altered by point mutation, deletion or insertion in tumors of sporadic colorectal cancer patients. One (APO) of them was also found mutations in the germ line of both APC and GS patients. The identification of these genes has significant implications for understanding the pathogenesis of colorectal neoplasia and for the diagnosis and counseling of individuals with inherited predispositions to colorectal cancer. - adenomatous polyposis coli (APC) gene; chromosome 5q21; familial polyposis coli (FAP); Gardner's syndrome (GS); mutation
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  • ANDREW P. FEINBERG, LAURA A. JOHNSON, DAVID J. LAW, STEPHEN E. KUEHN, ...
    1992 Volume 168 Issue 2 Pages 149-152
    Published: 1992
    Released: August 31, 2006
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    FEINBERG, A.P., JOHNSON, L.A., LAW, D.J., KUEHN, S.E., STEENMAN, M., WILLIAMS, B.R.G., THOMAS, G., BOLAND, C.R., RAINIER, S. and KOI, M. Multiple Tumor Suppressor Genes in Multistep Carcinogenesis. Tohoku J. Exp. Med., 1992, 168 (2), 149-152-One of the most exciting areas of molecular oncology is the convergence of two independent lines of evidence suggesting involvement of multiple tumor suppressor genes in a given type of cancer. First, epidemiology and somatic cell genetics indicate the presence of multiple tumor suppressor genes in each of several malignancies. Second, cancers often lose multiple chromosomal regions during tumor progression. We will use two tumors, colorectal cancer and Wilms tumor, to illustrate the questions that multiple tumor suppressor genes raise. -allelic loss of chromosome; DNA methylation; multistep carcinogenesis; tumor suppressor genes; Wilms tumor (WT)
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  • TETSU AKIYAMA, TOHRU OHUCHI, SHUJI SUMIDA, SHI-QIONG XU, KUMAO TOYOSHI ...
    1992 Volume 168 Issue 2 Pages 153-157
    Published: 1992
    Released: August 31, 2006
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    AKIYAMA, T., OHUCHI, T., SUMIDA, S., XU, S. and TOYOSHIMA, K. Phosphorylation of the Antioncogene Products and Control of the Cell Cycle. Tohoku J. Exp. Med., 1992, 168 (2), 153-157-To investigate the function of the RB protein, we have studied cellular RB binding proteins and protein kinases responsible for phosphorylation of the RB protein. (1) We purified a cellular RB- associated protein p56 which competes with SV40 large T antigen for binding to the RB protein. (2) In another experiment, we screened expression libraries of U937 monocytic leukemia cell line by West-Western method and obtained two cDNA clones that encode RB binding proteins. (3) The RB protein was found to be phosphorylated by cdk2 and MAP kinase in vitro. Most of the sites phosphorylated in vitro are the same as those phosphorylated in vivo and the time course of activation of cdk2 in the cell cycle were similar to that of phosphorylation of the RB protein.-cdk2 kinase; MAP kinase; phosphorylation; RB protein; RB-associated protein
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  • RYUNOSUKE KANAMARU, CHIKASHI ISHIOKA
    1992 Volume 168 Issue 2 Pages 159-166
    Published: 1992
    Released: August 31, 2006
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    KANAMARU, R. and ISHIOKA, C. Mutations of the p53 Gene and Other Genes Involving in Human Colorectal Carcinogenesis. Tohoku J. Exp. Med., 1992, 168 (2), 159-166-In this study, structural changes of the p53 gene in primary specimens of human colorectal carcinomas were analyzed by polymerase chain reaction mediated-DNA sequencing method. Point mutations of p53 gene, including an intronic mutation case, were detected in 8 of 14 carcinomas (57%). Point mutations of the gene were also observed in 2 of 2 adenomas, suggesting that mutations occur prior to the carcinoma stage. These results support that p53 gene plays an important role in the development of colorectal cancer. The frequency of Ki-ras oncogene mutations was also studied by polymerase chain reaction-single strand conformation polymorphism analysis (PCR-SSCP). This resulted in the rate of 42% (10/24), a quite similar value obtained by other methods. As PCR-SSCP analysis is a convenient method to detect point mutation, we have now examined 24 colorectal cancers for the p53 gene by this method, and detected the mutations. Furthermore, expression of the DCC gene, a candidate of tumor suppressor gene involved in colorectal carcinogenesis, was examined by reverse transcriptase-mediated PCR (RT-PCR) assay, resulting in significant reduction on the DCC expression in 8 of 14 carcinoma cases (57%). -p53 gene; Ki-ras gene; DCC gene; colorectal cancer
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  • MINORU KOI, L.A. JOHNSON, A.P. FEINBERG
    1992 Volume 168 Issue 2 Pages 167-168
    Published: 1992
    Released: August 31, 2006
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    KOI, M., JOHNSON, L.A. and FEINBERG, A.P. A Novel General Strategy for Cloning Tumor Suppressor Genes Using Radiation-Reduced Chromosomal Superfragments. Tohoku J. Exp. Med., 1992, 168 (2), 167-168-To identify the tumor suppressor gene on human chromosome 11p15, we generated mouse microcell hybrids containing small transferable chromosome 11p15 fragments, which we have termed “DNA superfragments”. These hybrids will be used to identify which fragments contain a tumor suppressor gene by direct transfer of the fragments to tumor cells via microcell fusion. -DNA superfragments; tumor suppressor gene; microcell fusion
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  • TOM CURRAN
    1992 Volume 168 Issue 2 Pages 169-174
    Published: 1992
    Released: August 31, 2006
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    CURRAN, T. Fos and Jun: Oncogenic Transcription Factors. Tohoku J. Exp. Med., 1992, 168 (2), 169-174 -The fos and jun proto-oncogenes are members of the set of genes known as cellular immediate-early genes. Their expression is induced transiently by a great variety of extracellular stimuli associated with mitogenesis, differentiation processes or depolarization of neurons. They encode DNA binding proteins that form dimeric complexes through a leucine zipper structure that function as transcription factors. Continuous overexpression of fos or jun causes transformation of fibroblasts. Because of their ubiquitous expression it is believed that the target genes regulated by Fos and Jun are different in the many circumstances in which they are expressed. Thus, their functional specificity is likely to be regulated at several levels. We have uncovered several potential mechanisms that could contribute to their regulation. These include formation of a large number of heterodimeric complexes, post-translational modification by phosphorylation and a novel reduction/oxidation (redox) mechanism, presence of both positive and negative transcriptional domains and the ability of Fos and Jun to induce distinct bends in DNA structure. -fos; heterodimeric complex; jun; phosphorylation; reduction/oxidation
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  • MASAMI MURAMATSU, MITCHELL B. DICCIANNI, SHIGERU MORIMURA, TOSHIYA SUZ ...
    1992 Volume 168 Issue 2 Pages 175-182
    Published: 1992
    Released: August 31, 2006
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    MURAMATSU, M., DICCIANNI, M.B., MORIMURA, S., SUZUKI, T. and IMAGAWA, M. Complex Regulation of a Tumor Marker Expression. Enhancer and Silencer of the GST-P Gene. Tohoku J. Exp. Med., 1992, 168 (2), 175-182-Glutathione transferase P (GST-P) is expressed at high levels in precancerous lesions and hepatocellular carcinomas from a very early stage of chemically-induced hepatocarcinogenesis in the rat. To explore the molecular mechanisms of its specific activation, we are investigating the regulation mechanisms of the GST-P gene expression. By using gene technology, we have identified a strong enhancer, GPEI, at 2.5Kb and a silencer region at about 400 by upstream from the transcription start site. GPEI has a palindromic structure composed of two TPA- responsive element (TRE)-like sequences and binds at least three proteins including AP-1 (c-jun/c-fos). The silencer is composed of several sequences resembling each other and binds at least three proteins including SF-B/LAP/LIP. To determine whether the GST-P gene is activated together with a putative hepato- oncogene because they are located close to each other (cis-mechanism), or because they share a trans-acting factor that can activate both genes simultaneously (trans-mechanism), transgenic rats were produced with GST-P control region connected to the CAT reporter. The results unequivocally demonstrate that GST-P gene is activated position-independently by a trans-mechanism. -AP-1; enhancer; hepatocarcinogenesis; glutathione transferase P gene; silencer
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  • MAKI ASANO, HIDEAKI ISHIKAWA, YOSHIAKI ITO
    1992 Volume 168 Issue 2 Pages 183-187
    Published: 1992
    Released: August 31, 2006
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    ASANO, M., ISHIKAWA, H. and ITO, Y. Possible Involvement of Nuclear Oncoproteins in Regulation of DNA Replication. Tohoku J. Exp. Med., 1992, 168 (2), 183-187-Polyomavirus DNA replication requires its enhancer which contains an AP-1 site. We have shown that protooncogenes, c-jun and c-fos, whose products form heterodimeric transcription activator, AP-1, strongly stimulate polyomavirus DNA replication through the AP-1 site. The mechanisms by which this enhancer stimulates replication and transcription are different. By replacing the enhancer with the oligonucleotides representing the binding site of a transcription factor of interest, any transcription factor with the known binding sequence can be characterized in this replication assay. When Rel protein was examined, we were able to reveal a new domain in v-Rel protein which can stimulate replication strongly. Whether this domain also coincides with transforming potential of v-Rel protein is currently under investigation.-c-fos; c-jun; DNA replication; polyomavirus; Rel
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  • SHUNSUKE ISHII, TERUAKI NOMURA, CHIE KANEI-ISHII, HIDEKI NAKAGOSHI, TA ...
    1992 Volume 168 Issue 2 Pages 189-194
    Published: 1992
    Released: August 31, 2006
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    ISHII, S., NOMURA, T., KANEI-ISHII, C., NAKAGOSHI, H., SUDO, T. and SAWAZAKI, T. Transcriptional Control by myb Oncogene Product. Tohoku J. Exp. Med., 1992, 162 (2), 189-194-Structure and function of two domains of c-Myb were analyzed. We show that a leucine zipper structure is a component of the negative regulatory domain, because its disruption markedly increases both the transactivating and transforming capacities of c-Myb. Our results suggest that an inhibitor which suppresses transactivation binds to c-Myb through the leucine zipper, and that c-Myb can be oncogenically activated by mis-sense mutation. We also proposed a model, the “tryptophan cluster”, for the structure of the Myb DNA-binding domain, in which the three tryptophans form a cluster in the hydrophobic core in each repeat. The results of NMR analysis of repeat 3 revealed that the conserved tryptophans play a key role to make the hydrophobic core. -sequence-specific DNA-binding protein ; negative regulatory domain; leucine zipper; NMR
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  • ELIZABETH M. BLAOKWOOD, ROBERT N. EISENMAN
    1992 Volume 168 Issue 2 Pages 195-202
    Published: 1992
    Released: August 31, 2006
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    BLACKWOOD, E.M. and EISENMAN, R.N. Regulation of Myc: Max Complex Formation and Its Potential Role in Cell Proliferation. Tohoku J. Exp. Med., 1992, 168 (2), 195-202-The myc family of proto-oncogenes encodes short-lived nuclear phosphoproteins (Myc) involved in the control of cell proliferation and differentiation. Here we discuss the evidence for Myc's involvement in normal and abnormal cell proliferation and review recent information on Max, a novel protein that forms a sequence-specific DNA-binding complex with Myc. The properties of the Myc: Max heterodimeric complex suggest a model for how Myc may function in the cell. -basic-helix-loop-helix-Zip (b-HLH-Zip); dimerization; Max; Myc; proliferation
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  • YASUHUMI OHMORI, JUN-ICHI TANABE, MASANORI TERASHIMA, WATARU SHOJI, SH ...
    1992 Volume 168 Issue 2 Pages 203-210
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    OHMORI, Y., TANABE, J., TERASHIMA, M., SHOJI, W., TAKADA, S. and OBINATA, M. Role of c-Myc on Erythroid Differentiation. Tohoku J. Exp. Med., 1992, 168 (2), 203-210-In the early event of the induction of mouse erythroleukemia (MEL) cell differentiation, c-myc mRNA levels show a biphasic change. The elevated expression of a transfected c-myc gene inhibits the commitment and differentiation of MEL cell transformants. In the present work, we have introduced human c-myc mutants into MEL cells under the inducible promoter to define the functional domains of c-Myc involved in erythroid differentiation. The c-Myc domains necessary for commitment and differentiation are not colocalized; almost entire regions are required for inhibition of commitment, whereas domains II and IV that are essential for co-transforming activity with ras are required for inhibition of differentiation. Interestingly, mutants that delete domains for c-Myc dimerization motifs enhanced differentiation. Thus, c-Myc interferes with MEL cell differentiation by interacting with c-Myc partners and the induced protein(s) through dimerization domains. These results suggest that c-Myc may regulate commitment and differentiation by interacting with proteins through different domains. -c-Myc; commitment; differentiation; dimerization domain; erythoroleukemia cells
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  • SEN-ITIROH HAKOMORI
    1992 Volume 168 Issue 2 Pages 211-222
    Published: 1992
    Released: August 31, 2006
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    HAKOMORI, S. Functional Role of Glycosphingolipids in Tumor Progression. Tohoku J. Exp. Med., 1992, 168 (2), 211-222 -Molecular modeling of glycosphingolipids (GSLs), and their organization in membranes, suggest that GSL “patches” provide binding sites for interaction with ligands and adjacent cells, and that GSLs or their catabolites modulate transmembrane signaling. Aberrant GSL expression is a ubiquitous phenotype common to essentially all types of tumors, and leads to (i) formation of tumor-associated antigens defind by a large variety of monoclonal anti-bodies; (ii) aberrant adhesion favoring metastasis and invasiveness of tumor cells; and (iii) aberrant catabolism leading to altered transmembrane signaling and loss of growth control. Classical immunotherapy is based on (i). New approaches termed “antiadhesion” and “anti-signaling” therapy, based on (ii) and (iii), are hereby proposed. -antiadhesion therapy; glycosphingolipids; integrin family; anti-signaling therapy; tumor-associated antigen
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  • TAEKO MIYAGI, KEIKO HATA, KIMIO KONNO, SHIGERU TSUIKI
    1992 Volume 168 Issue 2 Pages 223-229
    Published: 1992
    Released: August 31, 2006
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    MIYAGI, T., HATA, K., KONNO, K. and TSUIKI, S. Multiple Forms of Mammalian Sialidase: Altered Expression in Carcinogenesis. Tohoku J. Exp. Med., 1992, 168 (2), 223-229-We have demonstrated that rat liver contains at least four types of sialidase differing in subcellular location, in catalytic property and immunologically. They are intralysosomal, cytosolic and membrane- associated sialidases I and II. Membrane sialidase I locates mainly in plasma membrane and sialidase II in lysosomal membrane. Immunological study reveals that the same types of sialidase exist in various tissues of rat and of other mammalian species. Based on these results, we examined the sialidases in rat hepatomas and in transformed cells of JB6 mouse epidermal cell. Hepatomas were found to possess four types of sialidase and the three of them altered quantitatively. Intralysosomal sialidase activity was higher but cytosolic and lysosomal membrane sialidase activities were lower in hepatomas than in control liver. When the sialidases of transformants of JB6 cells were compared with those of control cells, the activities of two lysosomal sialidases were decreased and contrarily plasma membrane sialidase was increased. We discussed a possible significance of the sialidase alterations in carcinogenesis. -sialidases; carcinogenesis; hepatoma; neoplastic alteration; subcellular localization
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  • KAZUO SUGAMURA, TOSHIKAZU TAKESHITA, HIRONOBU ASAO, SATORU KUMAKI, KAZ ...
    1992 Volume 168 Issue 2 Pages 231-237
    Published: 1992
    Released: August 31, 2006
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    SUGAMURA, K., TAKESHITA, T., ASAO, H., KUMAKI, S., OHBO, K., OHTANI, K. and NAKAMURA, M. The IL-2/IL-2 Receptor System: Involvement of a Novel Receptor Subunit, γ Chain, in Growth Signal Transduction. Tohoku J. Exp. Med., 1992, 168 (2), 231-237-We previously demonstrated the existence of a third component, p64, of IL-2 receptor (IL-2R), tentatively named the γ chain of IL-2R. Our recent studies provided evidence suggesting that the γ chain endows the β chain of IL-2R with IL-2 binding ability. The γ chain was detected in lymphoid transfectants of IL-2Rβ cDNA, which showed the intermediate- affinity IL-2R, but not in nonlymphoid transfectants of IL-2Rβ cDNA, which showed no IL-2 binding activity. The comparative study between two subclones of lymphoid MOLT4 transfectant of IL-2Rβ cDNA demonstrated that the amount of the γ chain coprecipitated with IL-2Rβ was proportional to numbers of the IL-2 binding sites. These results suggest the possibility that the γ chain associates with IL-2Rβ and has an important role in formation of the intermediate-affinity IL-2R complex. On the other hand, we have also demonstrated the association of IL-2Rβ with a certain tyrosine kinase, of which activation by IL-2 could be indispensable process at the initial pathway of signal transduction. - γ-chain; IL-2; IL-2 receptor; signal transduction; tyrosine kinase
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  • ADI F. GAZDAR
    1992 Volume 168 Issue 2 Pages 239-245
    Published: 1992
    Released: August 31, 2006
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    GAZDAR, A.F. The Molecular Biology of Lung Cancer. Tohoku J. Exp. Med., 1992, 168 (2), 239-245-Lung cancer arises atter a series of morphological changes, which take several years to progress from normal epithelium to invasive cancer. The morphological changes progress from hyperplasia, to metaplasia, to dysplasia, to carcinoma in situ, to invasive cancer and finally to metastatic cancer. Multiple molecular changes have been documanted in lung cancers, both small cell (SCLC) and non-small cell (NSCLC) types. The number of changes has been estimated to be in double digits. These changes include activation of dominant oncogenes myc family, (K-ras and neu genes), as well as loss of recessive growth regulatory genes or anti-oncogenes (p53, and RB as well as unidentified gene or genes on chromosome 3). However, cytogenetic and molecular genetic studies indicate that multiple other specific sites of actual or potential DNA loss may be present in lung cancers. Other changes may include development of drug resistance, and production of growth factors and their receptors. It is tempting to associate specific molecular changes with specific morphological changes, as has been attempted in the colon. However, because of the difficulties in serially sampling the respiratory tract, such studies have not been performed to date. Documentation of molecular changes in premalignant lesions and prospective studies of their prognostic effects will be necessary for the design of rational chemoprevention trials.-anti-oncogenes; K-ras; lung cancer; myc family; neu
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  • YOSHINORI MURAKAMI, YOUIOHI SUZUKI, YOSUKE KISHIMOTO, SETSUO HIROHASHI ...
    1992 Volume 168 Issue 2 Pages 247-255
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    MURAKAMI, Y., SUZUKI, Y., KISHIMOTO, Y., HIROHASHI, S., HAYASHI, K, and SEKIYA, T. Detection of DNA Aberrations in Human Cancers by Single-Strand Conformation Polymorphism Analysis of Polymerase Chain Reaction Products. Tohoku J. Exp. Med., 1992, 168 (2), 247-255-We have developed a simple, sensitive method, single-strand conformation polymorphism (SSCP) analysis, to detect a single nucleotide substitution in a DNA fragment amplified and labeled by the polymerase chain reaction (PCR). Mobility shift of single-stranded DNAs due to their specific conformations on non-denaturing polyacrylamide gel electrophoresis can reveal DNA aberrations. By the PCR-SSCP analysis of DNAs from surgical specimens of human cancers, mutated ras genes (17%) and aberrations of tumor suppressor p53 gene (53%) including loss of one of the two alleles and a mutation in the remaining allele were detected in lung carcinomas and aberrations of both of the p53 and retinoblastoma (RB) genes were detected exclusively in advanced hepatocellular carcinomas.-SSCP analysis; lung carcinoma; hepatocellular carcinoma; ras gene; p53 gene; RB gene
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  • FUMIAKI TEZUKA, RYOJI CHIBA, NORIYUKI IWAMA, TOHRU TAKAHASHI
    1992 Volume 168 Issue 2 Pages 257-263
    Published: 1992
    Released: August 31, 2006
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    TEZUKA, F., CHIBA, R., IWAMA, N. and TAKAHASHI, T. Development of the Human Colonic Adenocarcinoma from Adenoma as a Histopathologically Continuous Process. Tohoku J. Exp. Med., 1992, 168 (2), 257-263-The adenoma- carcinoma sequence of the human colon is usually divided into three separate steps according to the grade of epithelial dysplasia, i.e., adenomas with mild, moderate and severe dysplasia. In an attempt to re-examine whether or not this sequence can be morphologically separable as usually assumed, a total of 192 epithelial lesions including adenomas with various grades of dysplasia were analyzed, relying on morphometrical and multivariate-statistical techniques. Histologic features of epithelial lesions were characterized by 10 quantitative parameters and subjected to 10-variate cluster analysis. In the result of computations, separation of neoplastic lesions into different groups proved to be rather ambiguous, not justifying the classification into three groups as generally expected. It was concluded that adenocarcinoma can develop from adenoma as a seemingly continuous process which may involve more steps than usually assumed.-adenoma-carcinoma sequence; colon; diagnosis; dysplasia; multivariate cluster analysis
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  • TOSHIHIRO KUMABE, YOSHIAKI SOHMA, TAKAMASA KAYAMA, TAKASHI YOSHIMOTO, ...
    1992 Volume 168 Issue 2 Pages 265-269
    Published: 1992
    Released: August 31, 2006
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    KUMABE, T., SOHMA, Y., KAYAMA, T., YOSHIMOTO, T. and YAMAMOTO, T. Overexpression and Amplification of α-PDGF Receptor Gene Lacking Exons Coding for a Portion of the Extracellular Region in a Malignant Glioma. Tohoku J. Exp. Med., 1992, 168 (2), 265-269-Overexpression of the α-Platelet Derived Growth Factor Receptor (α-PDGF) gene was detected in a case of malignant glioma. This overexpression was accompanied with amplification of rearranged α-PDGF receptor gene. We have isolated a cDNA for the transcript derived from the amplified receptor gene. Characterization of the cDNA revealed a deletion of 243 nucleotides coding for 81 amino acids in the extracellular region of the receptor. This in-frame deletion removed a part of the immunoglobulin-like domains in the extracellular region of the receptor. Analysis of the amplified α-PDGF receptor gene in the glioma indicated that exons coding for the 81 amino acids were lost by a gene deletion. The gene amplification was also detected in macroscopically normal cortex adjacent to the glioma from the same patient. However, the amplified gene in the macroscopically normal cortex had no major gene rearrangement. These data suggest that the overproduction of structurally altered α-PDGF receptor may take part in the onset and the development of malignant glioma. -α-PDGF receptor; gene amplification; gene rearrangement; glioma
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  • TAKAYUKI MIZOI, HARUO OHTANI, SEIKI MATSUNO, HIROSHI NAGURA
    1992 Volume 168 Issue 2 Pages 271-273
    Published: 1992
    Released: August 31, 2006
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    MIZOI, T., OHTANI, H., MATSUNO, S. and NAGURA, H. Immunohistochemical Identification of Transforming Growth Factor-β and Its Binding Protein in Human Gastrointestinal Carcinoma. Tohoku J. Exp. Med., 1992, 168 (2), 271-273-We attempted to clarify the tissue localization of TGF-β and latent TGF-β binding protein (LTBP) in human gastrointestinal carcinomas by immunohistochemistry. The immunoreactivity for TGF-β was observed in both carcinoma cells and stromal cells, particularly in diffuse-type gastric carcinoma. The immunoreactivity for LTBP was observed only in stromal cells. These results suggest that both carcinoma cells and stromal cells may produce TGF-β, and that only stromal cells may produce LTBP in gastrointestinal carcinoma.-TGF-β; latent TGF-β binding protein; gastrointestinal carcinoma; immunohistochemistry; immunoelectron microscopy
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  • YU HASHIMOTO, SHIN-IONI OSADA, SHIGEO OHNO, TOSHIO KUROKI
    1992 Volume 168 Issue 2 Pages 275-278
    Published: 1992
    Released: August 31, 2006
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    HASHIMOTO, Y., OSADA, S., OHNO, S. and KUROKI, T. A Ca2+-Independent Protein Kinase C, nPKCη: Its Structure, Distribution and Possible Function. Tohoku J. Exp. Med., 1992, 168 (2), 275-278-Protein kinase C consists of a protein family which can be classified into two major groups: Ca2+-dependent conventional protein kinase C and Ca2+-independent novel protein kinase C (nPKC). Among eight known members of protein kinase C family, we found that nPKCη (eta) isolated from cDNA library of mouse skin, is most abundant in epithelial tissues including skin and epithelia of digestive and respiratory tracts. These data suggest potential role of this isoform in growth, differentiation and carcinogenesis of epithelial tissues.-protein kinase C; tumor promotion; epithelial cells
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  • SUSUMU OHISHI, TAKAYASU KOBAYASHI, TAKAYUKI TERASAWA, TAKASHI MURAKAMI ...
    1992 Volume 168 Issue 2 Pages 279-282
    Published: 1992
    Released: August 31, 2006
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    OHISHI, S., KOBAYASHI, T., TERASAWA, T., MURAKAMI, T., ONODA, M., TSUIKI, S. and TAMURA, S. Alteration of the Level of Protein Phosphatase 2C (IA) mRNA during the Course of Differentiation of Skeletal Muscle Cells. Tohoku J. Exp. Med., 1992, 168 (2), 279-282-On Northern hybridization using the cDNA of type 2C protein phosphatase as a probe, substantial amount of the mRNA of type 2C protein phosphatase was detected in various organs of rats, suggesting that the type 2C protein phosphatase gene is a housekeeping gene. A relatively high level of the mRNA, however, was found in skeletal muscle compared with other organs. Similar results were obtained with the organs of mice. In addition, the mRNA level in C3H10T1/2 cells (embryonal mesenchymal cells of mice) was much lower than in mature skeletal muscle of mice. The mRNA level of type 2C protein phosphatase was enhanced in accordance with the differentiation of the C3H10T1/2 cells into myoblasts induced by the transfection of MyoD cDNA. These results suggest that type 2C protein phosphatase is related to the mechanism of differentiation of skeletal muscle cells.-skeletal muscle differentiaton; protein phosphatase
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  • REI ASAKAI, KAZUHIRO TAMURA, RYOHEI OKAMOTO
    1992 Volume 168 Issue 2 Pages 283-286
    Published: 1992
    Released: August 31, 2006
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    ASAKAI, R., TAMURA, K. and OKAMOTO, R. A Novel Steroidogenic Role of Suramin-Blocked Luteal Cell Growth Factors. Tohoku J. Exp. Med., 1992, 168 (2), 283-286-Growth factors synthesized in the ovarian corpus luteum (CL) have been implicated in the development of the CL. One of these growth factors is basic fibroblast growth factor which acts on luteal cells in an autocrine manner (Tamura et al. 1991; Asakai et al. 1992). To elucidate effects of these growth factors in the development of the CL, we cultured immature luteal cells with defined medium for a week in the presense or absence of a growth factor inhibitor, and measured progesterone in the medium as an indicator of cell differentiation. Culture of luteal cells showed an increased amount of progesterone for three days and continued to synthesize progesterone for at least another four days without serum and pituitary hormones. The addition of suramin, previously reported to inhibit autocrine growth stimulation, accelerate the daily progesterone production of luteal cells apparently by switching on the early onset of differentiation. Suramin also induced apoptosis of the cells after the 3rd day of culture. These data suggest that an autostimulation mechanism by growth factors plays a physiological role on normal cell differentiation, and it is not limited to neoplastic transformation.-basic fibroblast growth factor; bFGF receptor; autocrine loop; luteal cells; corpus luteum
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  • MASAFUMI KATAYAMA, MIKIO KAN
    1992 Volume 168 Issue 2 Pages 287-290
    Published: 1992
    Released: August 31, 2006
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    KATAYAMA, M. and KAN, M. Heparin-Binding (Fibroblast) Growth Factors are Potential Autocrine Regulators of Esophageal Epithelial Cell Proliferation. Tohoku J. Exp. Med., 1992, 168 (2), 287-290-A serum-free culture system supplemented with neural tissue extract for normal human esophagus was applied to the culture of mouse esophageal epithelium. Similar to mouse mesenchyme and skin epithelium, esophageal epithelial lines (MEE) emerged after serial culture. The cells had an apparent unlimited life-span, but retained morphology and other characteristics of normal epithelial cells. A screen for growth factors that stimulated growth of MEE cells in the absence of neural extract revealed that epidermal growth factor (EGF) and heparin-binding (fibroblast) growth factors (HBGF) were most effective. An HBGF-like activity was apparent in extracts of rapidly proliferating, but not quiescent MEE cells at low or confluent densities. A cloned cell line (MEE/C8) was selected from MEE cell cultures in the absence of neural extract. MEE/C8 cells proliferated independent of either EGF or HBGF at rates equal to MEE cells, cell extracts exhibited HBGF-like activity at all stages of proliferation, and the cells formed invasive tumors in syngenic hosts. The HBGF-like activity present in extracts of tumorigenic MEE/C8 cells had properties similar to HBGF-1 (acidic fibroblast growth factor).-esophagus; epithelial cells; heparin-binding growth factors; FGF; autocrine mechanisms
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  • SHINOBU SAKAMOTO, RYOHEI OKAMOTO
    1992 Volume 168 Issue 2 Pages 291-301
    Published: 1992
    Released: August 31, 2006
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    SAKAMOTO, S. and OKAMOTO, R. Thymidine Kinase Activity in Familial Adenomatous Polyposis. Tohoku J. Exp. Med., 1992, 168 (2), 291-301-Thymidine kinase (TK) activity of polyp tissue from patients with familial adenomatous polyposis (FAP) was measured and compared with that of normal colon, sporadic polyp and colorectal carcinoma tissues. Total TK activity in colonic carcinoma was 3-fold that of normal; this increase seems attributable mainly to increased activity of cytosolic TK isozyme activity; the colorectal TK isozymes were separated into two types, i.e., fetal type and adult type isozymes predominantly in, respectively, cytosolic and mitochondrial fractions, by DEAE- cellulose column chromatography. However, FAP polyp samples from 15 patients showed an average elevation of only 1.8-fold over normal. Examined individually, only 5 of the 15 FAP samples showed significant elevations in total TK activity. Furthermore, TK isozyme analysis revealed variable patterns of the cytosolic isozyme activity being elevated in some cases (8 of 15) and remaining low in others. Thus FAP polyps seem to be a heterogenous population with respect to DNA replicative activity, and cytosolic TK isozyme activity may constitute a biochemical marker for the subsequent development of colorectal carcinoma in FAP.-familial polyposis coli (FPC); tymidine kinase (TK); isozyme
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  • YOJI NAGASHIMA, YOHEI MIYAGI, KAORU SUMINO, YOSHIHARU OHAKI, MAKOTO UM ...
    1992 Volume 168 Issue 2 Pages 303-305
    Published: 1992
    Released: August 31, 2006
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    NAGASHIMA, Y., MIYAGI, Y., SUMINO, K., OHAKI, Y., UMEDA, M., OSHIMURA, M. and MISUGI, K. Characterization of Experimental Rat Nephroblastoma and Its Cell Line. Tohoku J. Exp. Med., 1992, 168 (2), 303-305- Rat nephroblastoma (Wilms' tumor) was induced by transplacental administration of N-ethyl- nitrosourea (ENU). The induced renal tumors were histologically compatible with human nephroblastoma. A cultured cell line (ENU-T-1) established from a xenotransplant, showed similar morphological and biological features to cultured embryonal kidney cells. Introduction of normal human chromosome #11 (#11) bearing Wilms' tumor suppressor gene(s) (WT) suppressed colony-forming ability on soft agar plates (CFA) but tumorigenicity of EMU-T-1 was not affected. Whereas tumorigenicity of human nephroblastoma cell line, SK-NEP-1 was completely suppressed, CFA was unchanged. These facts indicated that pathogenenetic mechanism is different between human and experimental rat nephroblastomas.- nephroblastoma (Wilms' tumor); transplacental carcinogenesis; cell line; chromosome transfer
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  • SHINCHIRO OKADA, SHUNSUKE KOBAYASHI, HIROHISA INABA, NOBUYUKI SATO, TO ...
    1992 Volume 168 Issue 2 Pages 307-310
    Published: 1992
    Released: August 31, 2006
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    OKADA, S., KOBAYASHI, S., INABA, H., SATO, N., HASUMI, T., SHOJI, W., YOSHIDA, H. and FUJIMURA, S. Flow Cytometric DNA Analysis of Lung Cancer Cell Lines. Tohoku J. Exp. Med., 1992, 168 (2), 307-310- Tumor DNA content (ploidy) was analyzed by use of flow cytometry (FCM) in 17 lung cancer cell lines which were subcultured in our laboratory. The study included 6 adenocarcinomas, 2 squamous cell carcinomas, 1 adenosquamous cell carcinoma, 5 large cell carcinomas, and 3 small cell carcinomas. Of the 17 lung carcinoma cell lines, 15 revealed aneuploid patterns with DNA index above 1.1, whereas one had diploid. The mean DNA index (DI) in adenocarcinoma, was 1.34±0.09, DI 1.6, in squamous cell carcinoma, DI 1.0 in adenosquamous cell carcinoma, DI 1.70±0.66 in large cell carcinoma, and DI 1.29 in small cell carcinoma. Of the 17 cell lines, three lines showed multiploid patterns with clinically poor prognosis and indicated heterogeneity. Flow cytometric DNA analysis using lung cancer cell lines could provide further basic study of lung cancer cells and give a useful information on the degree of the malignancy clinically.- lung cancer; in vitro; flow cytometry; DNA index
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  • YOSHINAO ABE, JUTARO TAKAHASHI, HIROSHI FUKUDA, KIKUYOSHI YOSHIDA
    1992 Volume 168 Issue 2 Pages 311-315
    Published: 1992
    Released: August 31, 2006
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    ABE, Y., TAKAHASHI, J., FUKUDA, H. and YOSHIDA, K. Cell Kinetic Study of Murine Jejunal Crypts during Multiple Doses per Day. Tohoku J. Exp. Med., 1992, 168 (2), 311-315- We studied cell kinetics of mouse jejunal crypts during multiple fractionation using double labeling methods. Mice were irradiated to the total body once a day or twice a day. Fraction size was 2 Gy. Overall time was 1, 3 and 5 days. Labeling index (LI), duration of S phase (Ts) and potential doubling time (Tpot) were assessed next morning following the irradiation schedule. Mice were administered both bromo-deoxyuridine (BrdUrd) and 3H- Thymidine ([3H]dT) with a constant interval. Removed jejunum were stained with immuno-histochemistry and, then, processed for autoradiography. BrdUrd and [3H]dT LIs were the same and were increased up to 5 days despite the fractionation schedule. After 1 day following 2 fx/day, both Ts and Tpot decreased significantly. For 1 fx/day treatment, neither Tpot nor Ts changed. After 5 day following 1 and 2 fx/day, both Ts and Tpots were the same and Tpots were significantly shorter than that obtained from control. It seems that proliferative responses between 1 and 2 fx/day were different, - cell kinetics; fractionation; labeling index; potential doubling time; jejunal crypt
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  • TAKEHIKO FUJIWARA, KAZUO KUBOTA, MASAO TADA, MASATOSHI ITOH, TACHIO SA ...
    1992 Volume 168 Issue 2 Pages 317-321
    Published: 1992
    Released: August 31, 2006
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    FUJIWARA, T., KUBOTA, K., TODA, M., ITOH, M., SATO, T., IWATA, R., SATO, K., TAKAHASHI, J., ABE, Y., FUKUDA, H. and IDO, T. N-(P-18)-Fluoroacetyl-D- Glucosamine: A New Positron Labeled Pharmaceutical for Cancer Study. Tohoku J. Exp. Med., 1992, 168 (2), 317-321- In order to evaluate the role of hexosamine metabolism in tumor tissue, we studied the biodistribution of N-(F-18)- fluoroacetyl-D-glucosamine (FAGlu) in male Donryu rats bearing poorly differentiated hepatomas (AH109A and AH272). Compare with the former result of the high tumor uptake of FAGlu in C3H/He mice bearing well differentiated spontaneous hepatoma, the tumor uptakes of FAGlu in these tumors showed the lower values. This suggested that spontaneous hepatoma maintained a high activity of glucosamine metabolism, while poorly differentiated hepatoma had little activity. Metabolism of glucosamine in tumor tissue may be another marker for characterizing tumors. We also discuss the tissue distribution of new F-18 labeled hexosamines, N-(F-18)-fluoroacetyl-D-mannosamine and N-(F-18)- fluoroacetyl-D-galactosamine in tumor bearing rats. - N-(F-18)- fluoroacetyl-D-glucosamine; N-(F-18)-fluoroacetyl-D-mannosamine; N-(F-18)- fluoroacetyl-D-galactosamine; tissue distribution; hepatoma
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  • TOSHIO KUDO, HISAAKI SAEKI, SUSUMU SAIJYO, NOBUYUKI SATO, MUNEO NUMASA ...
    1992 Volume 168 Issue 2 Pages 323-327
    Published: 1992
    Released: August 31, 2006
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    KUDO, T., SAEKI, H., SAIJYO, S., SATO, N., NUMASAKI, M. and TACHIBANA, T. New Strategies to Establish Human Monoclonal Antibodies. Tohoku J. Exp. Med., 1992, 168 (2), 323-327- In order to establish human monoclonal antibodies to any sort of antigens efficiently, we have made following two approaches. Our first approach is to improve cell fusion frequency. By improving our previous method for production of human hybridomas, we obtained higher frequency (1/700 vs. 1/ 5500) compared with our previous method by adding irradiated myeloma cells to culture of fusion cells and modifying the selective medium. Our second approach is to use a SCID-hu mouse for immunization. Since the injection of human PBL can result in the stable long-term reconstitution of a human immune system in SCID mouse, we tried to immune SCID-hu mouse with KLH. In the serum of immunized SCID-hu mouse, we obtained human IgG antibodies to KLH. Additionally, we succeeded in establishing human B lymphoblastoid cell lines which produced antibodies specific to KLH. These methods will open new prospects for the detection and therapy of cancer.- human monoclonal antibody; SCID-hu mouse; GIT medium; cell fusion
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  • KUNIHIKO ITOH, SHUNJI ISHIWATA, NAKAO ISHIDA, MICHINAO MIZUGAKI
    1992 Volume 168 Issue 2 Pages 329-331
    Published: 1992
    Released: August 31, 2006
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    ITOH, K., ISHIWATA, S., ISHIDA, N. and MIZUGAKI, M. Diagnostic Use of Anti-Modified Neucleoside Monoclonal Antibody. Tohoku J. Exp. Med., 1992, 168 (2), 329-331- By use of monoclonal antibodies (MoAbs) termed APU-6 and AMA-2, we determined the usefulness of urinary modified nucleosides, pseudouridine and 1-methyladenosine, as markers for malignancy. In patients with leukemia and other forms of cancer, these nucleosides elevated significantly and reflected the disease status of patients. The immunohistochemical analysis showed that cancer cells were specifically stained with the MoAbs. Chemical identification of the cellular components reactive with the MoAbs revealed that APU-6-associated antigens were mainly rRNA and AMA-2-associated antigens were mainly tRNA. These results suggest that APU-6 and AMA-2 would be useful tools for clinical and biological studies of cancer.- modified nucleosides; pseudouridine; 1- methyladenosine; monoclonal antibody; tumor marker
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  • CLAUDIO ANASETTI, JOHN A. HANSEN
    1992 Volume 168 Issue 2 Pages 333-343
    Published: 1992
    Released: August 31, 2006
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    ANASETTI, C. and HANSEN, J.A. Marrow Transplantation in Cancer Therapy. Tohoku J. Exp. Med., 1992, 168 (2), 333-343- Issues in bone marrow transplantation were addressed. Reconstitution of hematopoietic function is achieved by autologous, syngeneic, or allogeneic bone marrow transplant. Problems related to transplants from HLA mismatched family members, and HLA matched unrelated donors were also delineated.- marrow ablation; high dose chemotherapy; total body irradiation; unrelated donor registry; allograft reactions
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  • SHIGERU TSUCHIYA, MASAYOSHI MINEGISHI, HIROMI FUJIE, NAOKO MINEGISHI, ...
    1992 Volume 168 Issue 2 Pages 345-350
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    TSUCHIYA, S., MINEGISHI, M., FUJIE, H., MINEGISHI, N., OHASHI, Y., ITANO, M., MORITA, S., YAMAGUCHI, Y., SATO, T. and KONNO, T. Allogeneic Bone Marrow Transplantation for Malignant Hematologic Disorders in Children. Tohoku J. Exp. Med., 1992, 168 (2), 345-350- In the present study we carried out allogeneic bone marrow transplantation (BMT) in 14 leukemia children with high risk prognostic factors. Six patients with acute nonlymphocytic leukemia (ANLL), four with acute lymphocytic leukemia (ALL), two with chronic myelogenous leukemia (CML), and two with myelodysplastic syndrome (MDS). Among these patients, six with ANLL, two with ALL, one with CML and one with MDS were alive in complete remission 8 to 58 months post-BMT. Four patients died of relapse (one with ALL, and one with MDS), and chronic GVHD (one with ALL and one with CML). In six patients recombinant granulocyte colony stimulating factor (rG-CSF)was used to shorten the period of granulocytopenia. The mean time of recovery to granulocyte count of 500/mm3 was 13.2 days in the rG-CSF+group, being 15.9 days faster than that in the rG-CSF-group. In light of these results, allogeneic BMT is shown to be a choice of treatment for leukemia children with high risk prognostic factors and rG-CSF may be an effective reagent to prevent infectious episodes in BMT.- allogeneic bone marrow transplantation; leukemia; high risk prognostic factors; recombinant granulocyte colony stimulating factor
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  • JACK S. COHEN
    1992 Volume 168 Issue 2 Pages 351-359
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    COHEN, J.S. Selective Anti-Gene Therapy for Cancer: Principles and Prospects. Tohoku J. Exp. Med., 1992, 168 (2), 351-359-Oligodeoxynucleotides can act as antisense complements to target sense sequences of natural mRNAs to selectively regulate gene expression by translation arrest. This is a form of interventional gene therapy. Chemically modified analogs that are nucleaseresis- tant enable this strategy to be utilized in practice. Of the chemically modified backbone analogs of oligodeoxynucleotides we have used the phosphorothioate (PS) analog, in which a non-bridging phosphate oxygen atom is substituted with a sulfur atom. We have shown that these oligodeoxynucleotide analogs inhibit β-globin expression in cell free systems, and that they are taken up by cells. Specific sequences have been shown to selectively regulate viral and cellular gene expression, for example the bcl-2 oncogene that is found in ca. 90% of lymphomas. However, the PS analog has certain disadvantages, notably reduced hybridization and non-selective inhibition of translation. We have therefore synthesized a series of (PS-PO) co-polymers and characterized their properties. Other related approaches include catelytic ribozymes, and formation of triplexes by direct interaction of oligomers in the major groove of DNA. In general, a chemically modified oligodeoxynucleotide analog can be regurded as a novel form of informational drug. -oligodeoxynucleotide; antisense; DNA; RNA; phosphorothioate; cancer; bcl-2
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  • YOSHIYUKI HASHIMOTO, SHINYA SUZUKI
    1992 Volume 168 Issue 2 Pages 361-369
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    HASHIMOTO, Y. and SUZUKI, S. Basic Approach to Application of Liposomes for Cancer Chemotherapy. Tohoku J. Exp. Med., 1992, 168 (2), 361-369- The method for augmentation of systemic in vivo anticancer effect of liposomes (Lip) containing adriamycin (ADM) and endocytosis activity of cancer cells to liposomal preparations have been studied. Encapsulation of ADM in liposomes increases its maximal tolerated dose and pretreatment of animals bearing tumor with tumor necrosis factor α (TNF) resulted in effective targeting of ADM-Lip to tumor, leading to its augmented therapeutic effect, but only when TNF and ADM-Lip were administered with an appropriate interval. All human tumor cell lines tested showed endocytosis activity to liposomes but the activity was differed among different tumor cell lines.- adriamycin; tumor necrosis factor α (TNF-α); liposomes; antitumor effect
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  • TOSHIO TAKAHASHI, TOSHIHARU YAMAGUCHI, KAZUYA KITAMURA, AKINORI NOGUCH ...
    1992 Volume 168 Issue 2 Pages 371-374
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    TAKAHASHI, T., YAMAGUCHI, T., KITAMURA, K., NOGUCHI, A. and HONDA, M. Monoclonal Antibody-Drug Conjugate Therapy for the Patients with Colorectal Cancer. Tohoku J. Exp. Med., 1992, 168 (2), 371-374- Monoclonal antibody drug conjugate A7 was prepared from a mouse splenocyte immunized against human colon cancer. A7 reacted with 80 percent of colorectal cancer and pancreatic cancer. A7 was bound covalently to neocarzinostatin (NCS) to form A7-NCS. A7-NCS had strong cytotoxic activity in vivo and in vitro study. A total of 77 patients with colorectal cancer, including the patients with liver, lung and peritoneal metastasis, were treated with A7-NCS. There were some tumor reduction of liver metastasis on CT scan and pain relief. Follow up study of colorectal cancer patients treated with monoclonal antibody drug conjugate A7-NCS was carried out, with comparing to those treated conventional chemotherapy. Survival rate of the patients with postoperative liver metastasis treated with A7-NCS was slightly higher than that of the patients treated with conventional intraarterial infusion chemotherapy. There was no difference between the group treated with A7-NCS and that treated with conventional chemotherapy in the overall postoperative survival. Patients given a higher dose of the conjugate had a higher survival rate. There were no serious adverse effects in the patients given A7-NCS. Human anti-mouse antibody (HAMA) was detected in all A7-NCS treated patients. -monoclonal antibody; neocarcinostatin; colorectal cancer; antibody- drug conjugate; cytotoxicity
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  • SHUNSUKE KOBAYASHI, SHIGEFUMI FUJIMURA
    1992 Volume 168 Issue 2 Pages 375-386
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    KOBAYASHI, S. and FUJIMURA, S. Characterization and the Clinical Application of Cultured Human Pulmonary Carcinoma Cells. Tohoku J. Exp. Med., 1992, 168 (2), 375-386- We had developed a new method for the selective cultivation of cancer cells in short-term. As a result of these improvement in the culture technique, long-term subcultures of cancer cells are possible in about 80% of cases of small cell carcinoma of the lung and nearly 40% of cases of non-small cell carcinoma of the lung. 23 small cell lung carcinoma (SOLO) cell lines, 48 non-SOLO cell lines and 4 metastatic lung tumor cell lines were established in our institute using the culture method. Fractional culture of cells exhibiting the same growth pattern in primary culture produce several subtype cell lines, which can be used in experimental studies of the heterogeneity of lung cancer and in treatment of patients with lung cancer. Using subcultured cancer cells of the second or third generation, we have developed and have clinically utilized a simple sensitivity test with a Terasaki's microplate for anticancer drugs. In 15 surgical patients with SOLO treated between April 1982 and March 1985, the sensitivity test was used to select optimal anticancer drugs for postoperative chemotherapy. The routine use of the sensitivity test in selecting postoperative chemotherapy definitely improved the 3-year survival rate from 38% to 52%.-tissue culture; lung cancer; heterogeneity; sensitivity test
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  • YOSHIO HONMA, TAKASHI KASUKABE, MOTOO HOZUMI
    1992 Volume 168 Issue 2 Pages 387-391
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    HONMA, Y., KASUKABE, T, and HOZUMI, M. Control of Growth and Differentiation of Philadelphia Chromosome-Positive Leukemia Cells by Tyrosine Kinase Inhibitors. Tohoku J. Exp. Med., 1992, 168 (2), 387-391- Herbimycin A, a selective inhibitor of tyrosine kinase activity, induced differentiation of leukemia cells isolated from Philadelphia chromosome-positive chronic myelogenous leukemia patients. However, it did not induce differentiation of leukemia cells from acute myelogenous leukemia patients, although these cells could be induced to differentiate by treatment with appropriate compounds. A selective inhibitor of tyrosine kinase might be useful in chemotherapy of Philadelphia chromosome-positive leukemia.- Philadelphia chromosome-positive leukemia; acute myelogenous leukemia; chronic myelogenous leukemia; herbimycin A; tyrosine kinase inhibitor
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  • SHUNICHI SUGAWARA, NOBUKO KUMANO, YASUO SAIJO, SHUJI SUZUKI, YUKA NUMA ...
    1992 Volume 168 Issue 2 Pages 393-396
    Published: 1992
    Released: August 31, 2006
    JOURNALS FREE ACCESS
    SUGAWARA, S., KUMANO, N., SAIJO, Y., SUZUKI, S., NUMATA, Y., SATO, G. and MOTOMIYA, M. Protein Kinase C Activity in Human Leukemia Cell Lines with Reference to Sensitivity to Antineoplastic Agents. Tohoku J. Exp. Med., 1992, 168 (2), 393-396- Protein kinase C (PKC) regulates many cellular processes. In view of its possible relevance to the drug resistance, the levels of PKC activity were assessed in human leukemia cell lines with reference to the sensitivity to antineoplastic agents. K562/ADM exhibited approximately 2-fold higher levels of PKC activity as compared with the parental K562. After a 1-hr preincubation with Adriamycin (ADM) (0.5, 1, 10μM), PKC activity in K562 tended to increase dose-dependently, while no substantial alteration was found in K562/ADM. Cisplatin (CDDP) or etoposide was of no effect. The activity in THP-1/E was slightly lower than THP-1, and the basal level stayed unchanged with any one of the above durgs. These results suggest that in K562 increase in PKC activity with ADM may play a role in the process of acquisition of resistance.- protein kinase C; antineoplastic agents; human leukemia cell lines; drug resistance
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