Publications by authors named "Taisei Nomura"

44 Publications

A glypican-1-targeted antibody-drug conjugate exhibits potent tumor growth inhibition in glypican-1-positive pancreatic cancer and esophageal squamous cell carcinoma.

Neoplasia 2021 Sep 28;23(9):939-950. Epub 2021 Jul 28.

Department of Clinical Immunology, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan; Institute for Biomedical Sciences Molecular Pathophysiology, Iwate Medical University, Yahaba, Iwate, Japan; Division of Allergy and Rheumatology, Department of Internal Medicine, Iwate Medical University School of Medicine, Yahaba, Iwate, Japan. Electronic address:

An antibody-drug conjugate (ADC) is a promising therapeutic modality because selective and effective delivery of an anti-cancer drug is achieved by drug-conjugated antibody-targeting cancer antigen. Glypican 1 (GPC1) is highly expressed in malignant tumors, including pancreatic ductal adenocarcinoma (PDAC) and esophageal squamous cell carcinoma (ESCC). Herein, we describe the usefulness of GPC1-targeting ADC. Humanized anti-GPC1 antibody (clone T2) was developed and conjugated with monomethyl auristatin E (MMAE) via maleimidocaproyl-valine-citrulline-p-aminobenzyloxycarbonyl (mc-vc-PABC) linkers (humanized GPC1-ADC[MMAE]). Humanized GPC1-ADC(MMAE) inhibited the growth of GPC1-positive PDAC and ESCC cell lines via inducing cycle arrest in the G2/M phase and apoptosis in vitro. The binding activity of humanized GPC1-ADC(MMAE) with GPC1 was comparable with that of the unconjugated anti-GPC1 antibody. The humanized GPC1-ADC(MMAE) was effective in GPC1-positive BxPC-3 subcutaneously xenografted mice but not in GPC1-negative BxPC-3-GPC1-KO xenografted mice. To assess the bystander killing activity of the humanized GPC1-ADC(MMAE), a mixture of GPC1-positive BxPC-3 and GPC1-negative BxPC-3-GPC1-KO-Luc cells were subcutaneously inoculated, and a heterogenous GPC1-expressing tumor model was developed. The humanized GPC1-ADC(MMAE) inhibited the tumor growth and decreased the luciferase signal, measured with an in vivo imaging system (IVIS), which suggests that the suppression of the BxPC-3-GPC1-KO-Luc population. The humanized GPC1-ADC(MMAE) also inhibited the established liver metastases of BxPC-3 cells and significantly improved the overall survival of the mice. It exhibited a potent antitumor effect on the GPC1-positive PDAC and ESCC patient-derived xenograft (PDX) models. Our preclinical data demonstrate that GPC1 is a promising therapeutic target for ADC.
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http://dx.doi.org/10.1016/j.neo.2021.07.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8340053PMC
September 2021

Identification and Therapeutic Targeting of GPR20, Selectively Expressed in Gastrointestinal Stromal Tumors, with DS-6157a, a First-in-Class Antibody-Drug Conjugate.

Cancer Discov 2021 Jun 12;11(6):1508-1523. Epub 2021 Feb 12.

Daiichi Sankyo, Co., Ltd., Tokyo, Japan.

Currently, the only approved treatments for gastrointestinal stromal tumor (GIST) are tyrosine kinase inhibitors (TKI), which eventually lead to the development of secondary resistance mutations in KIT or PDGFRA and disease progression. Herein, we identified G protein-coupled receptor 20 (GPR20) as a novel non-tyrosine kinase target in GIST, developed new GPR20 IHC, and assessed GPR20 expression in cell lines, patient-derived xenografts, and clinical samples from two institutes (United States and Japan). We studied GPR20 expression stratified by treatment line, KIT expression, GIST molecular subtype, and primary tumor location. We produced DS-6157a, an anti-GPR20 antibody-drug conjugate with a novel tetrapeptide-based linker and DNA topoisomerase I inhibitor exatecan derivative (DXd). DS-6157a exhibited GPR20 expression-dependent antitumor activity in GIST xenograft models including a GIST model resistant to imatinib, sunitinib, and regorafenib. Preclinical pharmacokinetics and safety profile of DS-6157a support its clinical development as a potential novel GIST therapy in patients who are refractory or have resistance or intolerance to approved TKIs. SIGNIFICANCE: GPR20 is selectively expressed in GIST across all treatment lines, regardless of / genotypes. We generated DS-6157a, a DXd-based antibody-drug conjugate that exhibited antitumor activity in GIST models by a different mode of action than currently approved TKIs, showing favorable pharmacokinetics and safety profiles..
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http://dx.doi.org/10.1158/2159-8290.CD-20-1434DOI Listing
June 2021

Anti-glypican-1 antibody-drug conjugate is a potential therapy against pancreatic cancer.

Br J Cancer 2020 04 10;122(9):1333-1341. Epub 2020 Mar 10.

Laboratory of Immune Signal, National Institute of Biomedical Innovation, Health and Nutrition, Ibaraki, Japan.

Background: Pancreatic cancer (PDAC) is the most lethal malignancy. New treatment options for it are urgently required. The aim was to develop an antibody-drug conjugate (ADC) targeting glypican-1 (GPC-1) as a new therapy for PDAC.

Methods: We evaluated GPC-1 expression in resected PDAC specimens and PDAC cell lines. We then measured the antitumour effect of anti-GPC-1 monoclonal antibody conjugated with the cytotoxic agent monomethyl auristatin F (MMAF) in vitro and in vivo.

Results: GPC-1 was overexpressed in most primary PDAC cells and tissues. The PDAC cell lines BxPC-3 and T3M-4 strongly expressed GPC-1 relative to SUIT-2 cells. Compared with control ADC, GPC-1-ADC showed a potent antitumour effect against BxPC-3 and T3M-4, but little activity against SUIT-2 cells. In the xenograft and patient-derived tumour models, GPC-1-ADC significantly and potently inhibited tumour growth in a dose-dependent manner. GPC-1-ADC-mediated G2/M-phase cell cycle arrest was detected in the tumour tissues of GPC-1-ADC-treated mice relative to those of control-ADC-treated mice.

Conclusions: GPC-1-ADC showed significant tumour growth inhibition against GPC-1-positive pancreatic cell lines and patient-derived, GPC-1-positive pancreatic cancer tissues. Our preclinical data demonstrated that targeting GPC-1 with ADC is a promising therapy for patients with GPC-1-positive pancreatic cancer.
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http://dx.doi.org/10.1038/s41416-020-0781-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7189381PMC
April 2020

Study of glycosylation of prostate-specific antigen secreted by cancer tissue-originated spheroids reveals new candidates for prostate cancer detection.

Sci Rep 2020 02 17;10(1):2708. Epub 2020 Feb 17.

Laboratory of glycobiology, The Noguchi Institute, Tokyo, 173-0033, Japan.

Prostate-specific antigen (PSA) is the most frequently used biomarker for the screening of prostate cancer. Understanding the structure of cancer-specific glycans can help us improve PSA assay. In the present study, we analysed the glycans of PSA obtained from culture medium containing cancer tissue-originated spheroids (CTOS) which have similar characteristics as that of the parent tumour to explore the new candidates for cancer-related glycoforms of PSA. The glycan profile of PSA from CTOS was determined by comparing with PSA from normal seminal plasma and cancer cell lines (LNCaP and 22Rv1) using lectin chromatography and mass spectrometry. PSA from CTOS was mostly sialylated and the content of Wisteria floribunda agglutinin reactive glycan (LacdiNAc) was similar to that of PSA derived from seminal plasma and 22Rv1. Conversely, concanavalin A (Con A)-unbound PSA was definitely detected from the three cancer origins but was almost negligible in seminal PSA. Two novel types of PSA were elucidated in the Con A-unbound fraction: one is a high molecular weight PSA with highly branched N-glycans, and the other is a low molecular weight PSA without N-glycans. Furthermore, the existence of Lewis X antigen group on PSA was indicated. These PSAs will be candidates for new cancer-related markers.
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http://dx.doi.org/10.1038/s41598-020-59622-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7026178PMC
February 2020

Spermatogenesis-associated changes of fucosylated glycolipids in murine testis.

Hum Cell 2020 Jan 29;33(1):23-28. Epub 2019 Nov 29.

Animal and Human Model Project for Healthcare and Drug Development (Nomura Project), National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), 7-6-8 Asagi-Saito, Ibaraki, Osaka, 567-0085, Japan.

By targeted deletion of either the FUT1- or FUT2-gene for α1,2-fucosyltransferase, expression of FGM1 and FGA1, in murine testis was revealed to be sustained through unique interchangeability of the genes, indicating their significant roles for spermatogenesis. Accordingly, we examined the amounts of FGM1 and FGA1 in the testes of mice at 1-42 days after birth in comparison to those of several glycolipids including seminolipid. Although Forssman antigen and GM1 were present in relatively constant amounts during the period examined, GM3, which was the major one at 1 day, quickly decreased during development and had completely disappeared at 4 weeks. The following glycolipids were expressed in stage-specific manners, FGM1 for primary spermatocytes at 1 week, a seminolipid for secondary spermatocytes at 2 weeks, and GM3 lactone and FGA1 for spermatids and spermatozoa at 3 weeks. In fact, immunohistochemical staining with anti-FGM1 and anti-FGA1 antibodies demonstrated that FGM1 and FGA1 were distributed in the spermatocytes, and the spermatids and spermatozoa, respectively, and FGA1, together with seminolipid, were the immunogenic markers of spermatozoa. Thus, the fucosylation of glycolipids is a spermatogenesis-associated event, which should occur even with use of either the FUT1- or FUT2-gene.
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http://dx.doi.org/10.1007/s13577-019-00304-xDOI Listing
January 2020

A Novel HER3-Targeting Antibody-Drug Conjugate, U3-1402, Exhibits Potent Therapeutic Efficacy through the Delivery of Cytotoxic Payload by Efficient Internalization.

Clin Cancer Res 2019 12 30;25(23):7151-7161. Epub 2019 Aug 30.

Daiichi Sankyo Co., Ltd., Tokyo, Japan.

Purpose: HER3 is a compelling target for cancer treatment; however, no HER3-targeted therapy is currently clinically available. Here, we produced U3-1402, an anti-HER3 antibody-drug conjugate with a topoisomerase I inhibitor exatecan derivative (DXd), and systematically investigated its targeted drug delivery potential and antitumor activity in preclinical models.

Experimental Design: pharmacologic activities and the mechanisms of action of U3-1402 were assessed in several human cancer cell lines. Antitumor activity of U3-1402 was evaluated in xenograft mouse models, including patient-derived xenograft (PDX) models. Safety assessments were also conducted in rats and monkeys.

Results: U3-1402 showed HER3-specific binding followed by highly efficient cancer cell internalization. Subsequently, U3-1402 was translocated to the lysosome and released its payload DXd. While U3-1402 was able to inhibit HER3-activated signaling similar to its naked antibody patritumab, the cytotoxic activity of U3-1402 in HER3-expressing cells was predominantly mediated by released DXd through DNA damage and apoptosis induction. In xenograft mouse models, U3-1402 exhibited dose-dependent and HER3-dependent antitumor activity. Furthermore, U3-1402 exerted potent antitumor activity against PDX tumors with HER3 expression. Acceptable toxicity was noted in both rats and monkeys.

Conclusions: U3-1402 demonstrated promising antitumor activity against HER3-expressing tumors with tolerable safety profiles. The activity of U3-1402 was driven by HER3-mediated payload delivery via high internalization into tumor cells.
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http://dx.doi.org/10.1158/1078-0432.CCR-19-1745DOI Listing
December 2019

High-throughput screening in colorectal cancer tissue-originated spheroids.

Cancer Sci 2019 Jan 20;110(1):345-355. Epub 2018 Nov 20.

Department of Clinical Bio-resource Research and Development, Graduate School of Medicine, Kyoto University, Kyoto, Japan.

Patient-derived cancer organoid culture is an important live material that reflects clinical heterogeneity. However, the limited amount of organoids available for each case as well as the considerable amount of time and cost to expand in vitro makes it impractical to perform high-throughput drug screening using organoid cultures from multiple patients. Here, we report an advanced system for the high-throughput screening of 2427 drugs using the cancer tissue-originated spheroid (CTOS) method. In this system, we apply the CTOS method in an ex vivo platform from xenograft tumors, using machines to handle CTOS and reagents, and testing a CTOS reference panel of multiple CTOS lines for the hit drugs. CTOS passages in xenograft tumors resulted in minimal changes of morphological and genomic status, and xenograft tumor generation efficiently expanded the number of CTOS to evaluate multiple drugs. Our panel of colorectal cancer CTOS lines exhibited diverse sensitivities to the hit compounds, demonstrating the usefulness of this system for investigating highly heterogeneous disease.
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http://dx.doi.org/10.1111/cas.13843DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6317944PMC
January 2019

Enhanced fucosylation of GA1 in the digestive tracts of X-ray-irradiated mice.

Glycoconj J 2017 04 18;34(2):163-169. Epub 2016 Nov 18.

Animal Models of Human Diseases, National Institute of Biomedical Innovation, 7-6-8 Asagi-Saito, Osaka, Ibaraki, 567-0085, Japan.

In mice at 4 days after X-ray-irradiation at 0.5 Gy/min for 16 min, the tissue weights of immune organs, i.e., thymus and spleen, were decreased due to injury to lymphocytes by the X-rays. The resulting immunosuppressive condition allowed the growth of lactobacilli, i.e., L. murinus, which contained LacβTH-DG and possessed the ability to induce transcription of the fucosyltransferase gene for synthesis of FGA1. LacβTH-DG was detected in the jejunal and ileal contents of X-ray-irradiated mice, but not in those of control mice, whereas LacTetH-DG of L. johnsonii was present in the stomach and caecal contents of both mice. The amounts of FGA1 in the duodenal and jejunal tissues of X-ray-irradiated mice increased to 4- and 9-fold of those in controls, respectively. Reflecting the enhanced fucosylation of GA1, the total amounts of FGA1 excreted into the contents of X-ray-irradiated mice were 1.4-times higher than those in controls. Also, when the extent of enhanced fucosylation of GA1 in several regions of the digestive tracts of X-ray-irradiated mice was compared with that in immune deficient nude, scid and pIgR(-/-) mice, the more than 4-fold increases of FGA1 observed in duodenal and jejunal tissues corresponded to those in pIgR(-/-) mice without secretory IgA. Since an increased amount of FGA1 in the small intestine was observed only 4 days after X-ray-irradiation, and diminished synthesis of FGA1 occurred on administration of penicillin and streptomycin, fucosylation of GA1 in the small intestine was revealed to occur quickly in response to a change in the intestinal bacterial population.
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http://dx.doi.org/10.1007/s10719-016-9746-3DOI Listing
April 2017

Neutron relative biological effectiveness in Hiroshima and Nagasaki atomic bomb survivors: a critical review.

J Radiat Res 2016 Nov 10;57(6):583-595. Epub 2016 Sep 10.

National Institute of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki-shi, Osaka 567-0086, Japan.

The calculated risk of cancer in humans due to radiation exposure is based primarily on long-term follow-up studies, e.g. the life-span study (LSS) on atomic bomb (A-bomb) survivors in Hiroshima and Nagasaki. Since A-bomb radiation consists of a mixture of γ-rays and neutrons, it is essential that the relative biological effectiveness (RBE) of neutrons is adequately evaluated if a study is to serve as a reference for cancer risk. However, the relatively small neutron component hampered the direct estimation of RBE in LSS data. To circumvent this problem, several strategies have been attempted, including dose-independent constant RBE, dose-dependent variable RBE, and dependence on the degrees of dominance of intermingled γ-rays. By surveying the available literature, we tested the chromosomal RBE of neutrons as the biological endpoint for its equivalence to the microdosimetric quantities obtained using a tissue-equivalent proportional counter (TEPC) in various neutron fields. The radiation weighting factor, or quality factor, Q, of neutrons as expressed in terms of the energy dependence of the maximum RBE, RBE, was consistent with that predicted by the TEPC data, indicating that the chromosomally measured RBE was independent of the magnitude of coexisting γ-rays. The obtained neutron RBE, which varied with neutron dose, was confirmed to be the most adequate RBE system in terms of agreement with the cancer incidence in A-bomb survivors, using chromosome aberrations as surrogate markers. With this RBE system, the cancer risk in A-bomb survivors as expressed in unit dose of reference radiation is equally compatible with Hiroshima and Nagasaki cities, and may be potentially applicable in other cases of human radiation exposure.
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http://dx.doi.org/10.1093/jrr/rrw079DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5137296PMC
November 2016

Absence of lactobacilli containing glycolipids with the α-galactose epitope and the enhanced fucosylation of a receptor glycolipid GA1 in the digestive tracts of immune-deficient scid mice.

J Biochem 2015 Jul 9;158(1):73-82. Epub 2015 Mar 9.

Department of Biochemistry, Faculty of Science and Technology, Kinki University, 3-4-1 Kowakae, Higashiosaka, Osaka 577-8502, Japan; Department of Obstetrics and Gynecology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan; and Animal Models of Human Diseases, National Institute of Biomedical Innovation, 7-6-8 Asagi-Saito, Ibaraki, Osaka 567-0085, Japan.

The Lactobacillus species in the digestive tracts of immune-deficient scid mice was distinct from that in control mice, i.e. Lactobacillus murinus in scid and L. johnsonii in control mice, according to their 16S-rRNA, indicating that a symbiotic relationship between lactobacilli and a host is established under pressure from the immune system. The caecal and colonal contents rich in L. murinus of scid mice were loose with a strong sour smell, resulting in diarrhoea, and those with L. johnsonii in control mice included abundant solid materials. Lactobacillus glycolipids were revealed to be recognized by the immune system, and by TLC-immunostaining, LacTetH-DG (Galα1-6Galα1-6Galα1-2Glcα1-3'DG) of L. johnsonii was detected in the stomach, caecum and colon of control mice, but not in those of scid ones, in which fucosylation of a receptor GA1 for L. johnsonii was enhanced more than 4-fold compared with in the control mice. Thus, structural modification of receptor glycolipids was revealed to occur in the process of establishment of a symbiotic relationship between lactobacilli and a host. LacTetH-DG was also immunogenic to human, because of the presence of natural antibodies against it, and the antibody binding to it was comparable to that of blood group- and species-related glycosphingolipids.
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http://dx.doi.org/10.1093/jb/mvv021DOI Listing
July 2015

Altered Actions of Memantine and NMDA-Induced Currents in a New Grid2-Deleted Mouse Line.

Genes (Basel) 2014 Dec 11;5(4):1095-114. Epub 2014 Dec 11.

Laboratory of Cell Signaling and Metabolic Disease, National Institute of Biomedical Innovation, Saito-Asagi, Ibaraki, Osaka 567-0085, Japan.

Memantine is a non-competitive antagonist of the N-methyl-D-aspartate (NMDA) receptor, and is an approved drug for the treatment of moderate-to-severe Alzheimer's disease. We identified a mouse strain with a naturally occurring mutation and an ataxic phenotype that presents with severe leg cramps. To investigate the phenotypes of these mutant mice, we screened several phenotype-modulating drugs and found that memantine (10 mg/kg) disrupted the sense of balance in the mutants. Moreover, the mutant mice showed an attenuated optokinetic response (OKR) and impaired OKR learning, which was also observed in wild-type mice treated with memantine. Microsatellite analyses indicated that the Grid2 gene-deletion is responsible for these phenotypes. Patch-clamp analysis showed a relatively small change in NMDA-dependent current in cultured granule cells from Grid2 gene-deleted mice, suggesting that GRID2 is important for correct NMDA receptor function. In general, NMDA receptors are activated after the activation of non-NMDA receptors, such as AMPA receptors, and AMPA receptor dysregulation also occurs in Grid2 mutant mice. Indeed, the AMPA treatment enhanced memantine susceptibility in wild-type mice, which was indicated by balance sense and OKR impairments. The present study explores a new role for GRID2 and highlights the adverse effects of memantine in different genetic backgrounds.
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http://dx.doi.org/10.3390/genes5041095DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4276928PMC
December 2014

Histologic evaluation of human benign prostatic hyperplasia treated by dutasteride: a study by xenograft model with improved severe combined immunodeficient mice.

Urology 2015 Jan 6;85(1):274.e1-8. Epub 2014 Nov 6.

Animal Models of Human Diseases, National Institute of Biomedical Innovation, Ibaraki, Osaka, Japan.

Objective: To evaluate histologic change in human prostate samples treated with dutasteride and to elucidate direct effects of dutasteride on human prostate tissue, the present study was conducted by using a xenograft model with improved severe combined immunodeficient (super-SCID) mice, although it is well known that dutasteride reduces prostate volume.

Methods: After establishment of a xenograft model of human benign prostatic hyperplasia in morphology and function, samples implanted into super-SCID mice with and without dutasteride were evaluated pathohistologically at 2 and 6 months after initiation of dutasteride administration.

Results: The proliferative index evaluated by Ki-67 staining was significantly lower in the dutasteride group than the control at 2 and 6 months after administration. Apoptotic index evaluated by the terminal transferase TdT-mediated dUTP-biotin nick end labeling staining was higher in the dutasteride group than the control at 2 and 6 months after administration. Quick scores in the dutasteride group for staining of both cyclooxygenase-2 (Cox-2) and Ras homolog gene family, member A (RhoA) were significantly lower than those in the control group at 2 and 6 months after administration.

Conclusion: Dutasteride inhibits cell proliferation and induces apoptosis of prostatic cells, causing a reduced prostate volume. Furthermore, decreased expression of Cox-2 and RhoA within benign prostatic hyperplasia tissue by dutasteride may induce an early effect on improvement of lower urinary tract symptoms, probably by attenuating inflammation reaction of the prostate and decreasing intraurethral pressure, other than the mechanism of reduced prostate volume.
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http://dx.doi.org/10.1016/j.urology.2014.09.024DOI Listing
January 2015

p53-Dependent suppression of genome instability in germ cells.

Mutat Res 2014 Feb 7;760:24-32. Epub 2014 Jan 7.

Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, B4, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan. Electronic address:

Radiation increases mutation frequencies at tandem repeat loci. Germline mutations in γ-ray-irradiated medaka fish (Oryzias latipes) were studied, focusing on the microsatellite loci. Mismatch-repair genes suppress microsatellite mutation by directly removing altered sequences at the nucleotide level, whereas the p53 gene suppresses genetic alterations by eliminating damaged cells. The contribution of these two defense mechanisms to radiation-induced microsatellite instability was addressed. The spontaneous mutation frequency was significantly higher in msh2(-/-) males than in wild-type fish, whereas there was no difference in the frequency of radiation-induced mutations between msh2(-/-) and wild-type fish. By contrast, irradiated p53(-/-) fish exhibited markedly increased mutation frequencies, whereas their spontaneous mutation frequency was the same as that of wild-type fish. In the spermatogonia of the testis, radiation induced a high level of apoptosis both in wild-type and msh2(-/-) fish, but negligible levels in p53(-/-) fish. The results demonstrate that the msh2 and p53 genes protect genome integrity against spontaneous and radiation-induced mutation by two different pathways: direct removal of mismatches and elimination of damaged cells.
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http://dx.doi.org/10.1016/j.mrfmmm.2013.12.004DOI Listing
February 2014

Enhanced expression of fucosyl GA1 in the digestive tract of immune-deficient scid, nude and pIgR(-/-) mice.

J Biochem 2013 Dec 1;154(6):541-9. Epub 2013 Oct 1.

Department of Biochemistry, Faculty of Science and Technology, Kinki University, 3-4-1 Kowakae, Higashiosaka, Osaka 577-8502; Yakult Central Institute for Microbiological Research, 1796 Yaho, Kunitachi-shi, Tokyo 186-8650; and Animal Models of Human Diseases, National Institute of Biomedical Innovation, 7-6-8 Asagi-Saito, Ibaraki, Osaka 567-0085, Japan.

Fucosylation of GA1 in murine intestinal epithelia occurs through transcriptional induction of α1,2-fucosyltransferase along with bacterial infection, but the mechanism has not been clearly characterized as to whether it is induced as a result of an immune response to bacteria or of genetic manipulation of the host by bacteria. Accordingly, we analysed the expression of fucosyl GA1 (FGA1) and fucosyltransferase activity in the digestive tracts of immune-deficient scid, nude and pIgR(-/-) mice. In comparison with those in control mice bred under the same SPF circumstances, the amount of FGA1 and the α1,2-fucosyltransferase activity were significantly increased in the immune-deficient mice, indicating that the immune system is not involved in induction of the α1,2-fucosyltransferase gene. Reflecting the enhanced synthesis of FGA1, the total amounts of FGA1 in the intestinal contents of immune-deficient mice were higher than those in control mice. Also, the major faecal bacteria grown on a MRS agar plate were different in immune-deficient and control mice as follows, Lactobacillus murinus for scid and pIgR(-/-) mice, and Lactobacillus johnsonii for their control, and Enterococcus faecalis for nude mice and Lactococcus garvieae for the control, indicating that an alteration in the intestinal lactobacilli is partly involved in the induction of α1,2-fucosyltransferase.
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http://dx.doi.org/10.1093/jb/mvt087DOI Listing
December 2013

Changes in bacterial glycolipids as an index of intestinal lactobacilli and epithelial glycolipids in the digestive tracts of mice after administration of penicillin and streptomycin.

Glycoconj J 2013 Dec 1;30(9):889-97. Epub 2013 Sep 1.

Department of Biochemistry, Faculty of Science and Technology, Kinki University, 3-4-1 Kowakae, Higashiosaka, Osaka, 577-8502, Japan,

The major lipid constituent of symbiotic gram-positive bacteria in animals are phosphatidylglycerol, cardiolipin and dihexaosyl diglycerides (DH-DG), whose hydrophobic structures are characteristic of the environments, and the carbohydrate structures of DH-DGs are bacterial species-characteristic. Immunization of rabbits with intestinal lactobacilli generated antibodies against DH-DGs and their modified structures, among which Galα1-6-substituted DH-DG, i.e., Lactobacillus tetrahexaosyl diglyceride (LacTetH-DG), reacted with antibodies more intensely than DH-DG. Whereas, from the 16S-rRNA sequence, the intestinal lactobacilli in murine digestive tracts were revealed to be L. johnsonii, in which LacTetH-DG is present at the concentration of 2.2 ng per 1 × 10(6) cells. To obtain more accurate estimates of intestinal lactobacilli in several regions of the digestive tract of mice, LacTetH-DG was detected by TLC-immunostaining with anti-Lactobacillus antisera, being found in the stomach, cecum and colon of normal breeding mice, 1.0 × 10(9), 3.5 × 10(9) and 7.4 × 10(9) cells, respectively. Administration of penicillin and streptomycin for 6 days resulted in a reduction in the number of intestinal lactobacilli, the levels being 0 %, 30 % and 4 % of the control ones in the stomach, cecum and colon, respectively, which was associated with the accumulation of the contents in the tracts from the stomach to the cecum and with diarrhea. In addition, a reduced amount of fucosyl GA1 (FGA1) and a compensatory increase in GA1 due to the reduced activity of α1,2-fucosyltransferase in the small intestine and the enhanced discharge of FGA1 into the contents occurred in mice, probably due to the altered population of bacteria caused by administration of penicillin and streptomycin.
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http://dx.doi.org/10.1007/s10719-013-9494-6DOI Listing
December 2013

Bacterial species-characteristic profiles of molecular species, and the antigenicity of phospholipids and glycolipids in symbiotic Lactobacillus, Staphylococcus and Streptococcus species.

Glycoconj J 2012 May 26;29(4):199-209. Epub 2012 May 26.

Department of Biochemistry, Faculty of Science and Technology, Kinki University, 3-4-1 Kowakae, Higashiosaka, Osaka, 577-8502, Japan.

Human symbiotic bacteria, Lactobacillus reuteri (LR) in the intestines, Staphylococcus epidermidis (SE) in skin and Streptococcus salivalis (SS) in the oral cavity, contain dihexaosyl diglycerides (DH-DG) in concentrations equivalent to those of phosphatidyl glycerol (PG) and cardiolipin (CL), together with mono- to tetrahexaosyl DGs. The molecular species, as the combination of fatty acids in the DG moiety, were revealed to be bacterial species-characteristic, but to be similar between glycolipids and phospholipids in individual bacteria, the major ones being 16:0 and cy19:0 for LR, ai15:0 and ai17:0 for SE, and 16:0 and 18:1 for SS, respectively. The carbohydrate structures of DH-DGs were also bacterial species-characteristic, being Galα1-2Glcα for LR, Glcβ1-6Glcβ for SE, and Glcα1-2Glcα for SS, respectively. Also, bacterial glycolipids were revealed to provide antigenic determinants characteristic of bacterial species on immunization of rabbits with the respective bacteria. Anti-L. johnsonii antiserum intensely reacted with tri- and tetrahexaosyl DGs, in which Galα was bound to DH-DG through an α1-6 linkage, as well as with DH-DG from LR. Although anti-SE antiserum preferentially reacted with DH-DG from SE, anti-SS antiserum reacted with DH-DG from SS and, to a lesser extent, with DH-DGs from LR and SE. But, both anti-SE and anti-SS antiserum did not react at all with monohexaosyl DG or glycosphingolipids with the same carbohydrates at the nonreducing terminals. In addition, 75 % of human sera, irrespective of the ABO blood group, were found to contain IgM to tri- and tetrahexaosyl DGs from LR, but not to DH-DGs from LR, SE and SS.
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http://dx.doi.org/10.1007/s10719-012-9393-2DOI Listing
May 2012

Characterization of novel glycolipid antigens with an α-galactose epitope in lactobacilli detected with rabbit anti-Lactobacillus antisera and occurrence of antibodies against them in human sera.

J Biochem 2011 Nov 22;150(5):515-23. Epub 2011 Jul 22.

Department of Biochemistry, Kinki University, Kowakae, Higashiosaka, Osaka, Japan.

Anti-Lactobacillus johnsonii (LJ) antisera generated by immunization of rabbits with LJ reacted with glyceroglycolipids in LJ, i.e. dihexaosyl diacylglycerol (DH-DG), trihexaosyl DG (TH-DG) and tetrahexaosyl DG (TetH-DG), whose reactivities with antisera increased proportionally with longer carbohydrate chains of glycolipids. Structural analyses of glycolipids from LJ revealed that DH-DG was Galα1-2Glcα1-3'DG, and TH-DG and TetH-DG were novel derivatives of it with α-Gal at the non-reducing terminal, i.e. Galα1-6Galα1-2Glcα1-3'DG and Galα1-6Galα1-6Galα1-2Glcα1-3'DG, respectively. DH-DG was commonly present in several lactobacilli examined, but TetH-DG was restricted to LJ, L. intestinalis and L. reuteri, while the TH-DGs from L. casei were Glc1-6Galα1-2Glcα1-3'DG and an esterified derivative of it, Glc1-6Galα1-2Glc(6-fatty acid)α1-3'DG, as reported in the literature. Anti-LJ antisera reacted with TH-DG and esterified TH-DG from L. casei to lesser extents, but not at all with gentibiosyl DG from Staphylococcus epidermidis or kojibiosyl DG from Streptococcus salivalis or sphingoglycolipids containing α-Gal residues. The major molecular species of glycolipids obtained from lactobacilli were 11-octadecenoic and 11,12-methylene-octadecanoic acids-containing ones. Also, human IgM antibodies against TH-DG and TetH-DG from LJ were detected in human sera, with various antibody titres, indicating that an immune reaction to symbiotic lactobacilli occurs against their glycolipid antigens, TH-DG and TetH-DG.
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http://dx.doi.org/10.1093/jb/mvr091DOI Listing
November 2011

Excretion into feces of asialo GM1 in the murine digestive tract and Lactobacillus johnsonii exhibiting binding ability toward asialo GM1. A possible role of epithelial glycolipids in the discharge of intestinal bacteria.

Glycoconj J 2011 Jan 21;28(1):21-30. Epub 2010 Dec 21.

Department of Biochemistry, Faculty of Science and Technology, Kinki University, 3-4-1 Kowakae, Higashiosaka, Osaka, 577-8502, Japan.

In the digestive tract of mice (HR-1, 5 months old, ♀), asialo GM1 (GA1) exhibiting receptor activity toward several intestinal bacteria was preferentially expressed in the small intestine. Also, less than 10% of GA1 in the small intestine was converted into fucosylated and sulfated derivatives, but it was completely converted to fucosyl GA1 (FGA1) in the stomach, cecum and colon. Among the lipid components in these tissues, glycolipids other than Forssman antigen and cholesterol sulfate (CS) were present in the digestive tract contents. However, sulfated GA1, sulfatide and fucosyl GM1 in the gastro-intestinal contents were not present in the cecal and colonic contents, in which the major glycolipids were ceramide monohexoside (CMH), GA1 and FGA1. The total amount of GA1 in the whole contents was 20% of that in the tissues. Thus, glycolipids were stable during the process of digestion, and excreted from the body together with cholesterol and CS. On the other hand, Lactobacillus johnsonii (LJ), whose receptor is GA1, was detected in the cecal and colonic contents on sequential analysis of 16S-ribosomal RNA and TLC-immunostaining of antigenic glycolipids with anti-LJ antiserum. LJ was found to comprise 20% of the total bacteria cultured in the lactobacillus medium under aerobic conditions, and to be present in the cecal and colonic contents, 9.8 × 10(7) cells versus 37 μg GA1 and 1.4 × 10(8) cells versus 49 μg GA1, respectively. Thus, GA1 in the contents might facilitate the discharge of intestinal bacteria by becoming attached them to prevent their irregular diffusion.
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http://dx.doi.org/10.1007/s10719-010-9320-3DOI Listing
January 2011

CRABP1-reduced expression is associated with poorer prognosis in serous and clear cell ovarian adenocarcinoma.

J Cancer Res Clin Oncol 2011 Apr 23;137(4):715-22. Epub 2010 Jun 23.

Department of Obstetrics and Gynecology, Osaka Rosai Hospital, 1179-3 Nagasone, Kita-ku, Sakai, Osaka 591-8025, Japan.

Purpose: CRABP1 is a modulator of retinoic acid function. The aim of the present study was to investigate CRABP1 expression and its clinical significance in ovarian carcinoma.

Methods: Expression of CRABP1 protein was investigated by immunohistochemical analysis in 100 ovarian carcinomas of various histological sub-types, including serous and clear cell adenocarcinomas. Relationship of CRABP1 expression to clinical features, including prognosis, was analyzed.

Results: Reduced expression of CRABP1 protein was detected especially frequently in the serous and clear cell adenocarcinomas sub-types, 50% (20 of 40) and 38% (10 of 26) of cases, respectively. We found that in both serous and clear cell adenocarcinomas overall survival was significantly poorer in the cases with reduced CRABP1 expression compared to similar cases where expression was maintained, irrespective of the disease stage (P = 0.0073 and 0.049, respectively). Disease-free survival of the serous and clear cell adenocarcinoma cases with reduced CRABP1 expression was significantly poorer, compared to the cases whose CRABP1 expression was maintained (P = 0.024). Multivariate analysis showed that reduced expression of CRABP1 was a significantly important prognostic factor (adjusted hazard ratio: 8.189 (95% CI, 2.186-30.672, P = 0.0019)).

Conclusions: The present study is the first to demonstrate that the reduced expression of CRABP1 has a potential as a prognostic marker for serous adenocarcinoma which is the most frequent histological ovarian tumor type and also for clear cell carcinoma that often exhibits chemo-resistance. Further study is necessary to clarify how CRABP1 protein expression was altered and how CRABP1 affects ovarian carcinoma cells.
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http://dx.doi.org/10.1007/s00432-010-0930-8DOI Listing
April 2011

Effects of fission neutrons on human thyroid tissues maintained in SCID mice.

Mutat Res 2010 Feb 12;696(2):107-13. Epub 2010 Jan 12.

Department of Radiation Biology and Medical Genetics, Osaka University, Suita, Osaka, Japan.

Morphology and function (secretion of thyroid hormone) of human thyroid tissues from Graves' disease patients are well maintained in C57BL/6J-scid mice. Serum level of thyroid hormone was reduced by fission neutrons from the nuclear reactor UTR-KINKI, and changes in thyroid hormone by fission neutrons were bigger than those by low LET radiations, X-rays and (137)Cs gamma-rays, suggesting high relative biological effectiveness (RBE; 6.5) of fission neutrons. Microarray analyses revealed that about 3% of genes showed more than 4-fold change in gene expression in the unexposed thyroid tissues against surgically resected thyroid tissues from the same patient, probably due to the difficult oxygen and nutrient supply shortly after transplantation. Dose-dependent changes in gene expression against unexposed concurrent controls were observed with increasing doses of fission neutrons (0.2-0.6Gy) and (137)Cs gamma-rays (1.0-3.0Gy) and showed high RBE (4.2). Furthermore, there were some specific genes which showed more than 4-fold change in gene expression in all the thyroid tissues exposed to higher doses of radiation, especially neutrons (0.4 and 0.6Gy), but none at lower doses (0.2Gy of neutrons and 1.0 and 2.0Gy of gamma-rays). These genes related to degeneration, regeneration, apoptosis, and transcription, respond specifically and very sensitively to neutron injury in human thyroid tissues. This is the first experimental report that fission neutrons can induce some morphological and functional disorders in human tissues, showing high RBE against gamma-ray exposure. These results are useful to evaluate the risks of fission neutrons and cosmic rays to humans.
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http://dx.doi.org/10.1016/j.mrgentox.2009.12.017DOI Listing
February 2010

Distribution of receptor glycolipids for Lactobacilli in murine digestive tract and production of antibodies cross-reactive with them by immunization of rabbits with Lactobacilli.

J Biochem 2009 Aug 7;146(2):185-91. Epub 2009 Apr 7.

Department of Biochemistry, Kinki University, Kowakae, Higashiosaka, Osaka, Japan.

In the digestive tract of mice (HR-1 strain), glycolipids belonging to the ganglio-series were revealed to be expressed in region-specific manners, i.e. FGA1 and FGM1 in the stomach, GA1 in the small intestine, and FGA1 and sulphatides in the cecum. The amount of GA1 as a receptor glycolipid for Lactobacilli was especially higher in the small intestine than in the other regions, it comprising 1.6-2.8 microg/mg dry weight. On immunization of rabbits with Lactobacillus johnsonii and Lactobacillus intestinalis, both of which are murine intestinal bacteria, antibodies toward bacterial glycolipids, i.e. Galalpha1-2Glcalpha1-3DG, and tri- and tetrahexaosyl DGs, were effectively generated and, in addition, they were found to cross-react with GA1 and GalCer, but not with structurally related glycolipids such as Lc(4)Cer, nLc(4)Cer and IV(3)Galalpha-nLc(4)Cer, indicating that GA1 is a preferable antigen for anti-lactobacillus antisera and suggesting the presence of epitopes common to both Lactobacilli and the host. In fact, molecules reacting with anti-GA1 antibodies were detected among bacterial proteins on Western blotting, indicating a possible occurrence of the carbohydrate structure mimicking GA1 in bacterial proteins.
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http://dx.doi.org/10.1093/jb/mvp058DOI Listing
August 2009

Differential radiation sensitivity to morphological, functional and molecular changes of human thyroid tissues and bone marrow cells maintained in SCID mice.

Mutat Res 2008 Nov 19;657(1):68-76. Epub 2008 Aug 19.

Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan.

Morphology and function of human organs and tissues are well maintained in the improved SCID (severe combined immunodeficient) mice for a long period (approximately 3 years). To study the radiation-induced damage on human thyroid gland, human thyroid tissues transplanted to SCID mice were consecutively exposed to X-rays or 137Cs gamma-rays at high and low dose rates for approximately 2 years. Consecutive irradiation resulted in the disappearance of follicles and significant decrease of thyroid hormone secretion. Mutations in p53 and c-kit genes were induced significantly in human thyroid tissues from old head and neck cancer patients (av. 56.8 years, 4 males) and a Graves' disease patient (20 years, male) over the dose of 24 Gy (44.7+/-5.9 Gy, mean+/-S.E) and 11 Gy (20.2+/-7.8 Gy), respectively, while mutations were not detected at lower doses nor in unexposed matched controls (p < 0.01). There were significant differences in mutation frequency in the transplanted human thyroid tissues (31 years, female) between high dose rate (1.19 Gy/min; 8 in 20 tissues) and low dose rate (0.00023 Gy/min; 0 in 14 tissues) exposures (p < 0.01). Mutations were not detected in RET, K-ras and beta-catenin genes. Expression analysis by GeneChip indicated that gene expression was also well maintained in the transplanted human thyroid tissues. However, lower doses (1 or 3 Gy) of 137Cs gamma-rays can induce changes in gene expression in the transplanted human thyroid tissues. Furthermore, fatally irradiated SCID mice could survive with human bone marrow cell transplantation. When about half of mouse bone marrows were replaced by human bone marrow cells, the human bone marrow cells showed high sensitivity to gamma-irradiation; 28.0% and 0.45% survival after 0.5 and 2.0 Gy exposures, respectively.
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http://dx.doi.org/10.1016/j.mrgentox.2008.08.006DOI Listing
November 2008

Transgenerational effects from exposure to environmental toxic substances.

Authors:
Taisei Nomura

Mutat Res 2008 Jul-Aug;659(1-2):185-93. Epub 2008 Mar 28.

Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan.

Exposure of mouse germ cells to radiation and chemicals results in mutation, malformation, cancer and other adverse effects (e.g., functional disorders) in the offspring, though these findings have not been proven in human studies. Environmental toxic substances such as urethane (ethyl carbamate) which had been injected subcutaneously to 50 million people as a co-solvent of analgesics and dioxin (an endocrine disruptor) have been found to be associated with adverse effects in the progeny of mice after parental exposures. There are some reports on congenital malformations in the progeny of fathers who had been exposed to dioxin. However, these substances have not shown mutagenicity in in vitro assay systems such as bacterial systems even with S9, cell transformation assays, etc., in spite of their potent teratogenicity and carcinogenicity in in vivo systems. Urethane was negative in the mouse specific locus test for germ cell mutations, but elicited a significant response at the same loci in the offspring of mice treated during pregnancy. Further, urethane is a mutagen in Drosophila germ cell tests, specifically inducing point mutations. Dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin) does not induce in vivo somatic mutations in mice and rats. It does not induce chromosomal aberrations when the mouse and/or human sperm are treated, but induces mutations at ESTR (expanded simple tandem repeat) loci in mice at low frequencies and also congenital malformations. In this paper, we first present an overview of the results of our studies on transgenerational effects of these toxic substances, compare the results with those obtained after radiation exposure, and then discuss our subsequent studies to reconcile the problems underlying their mutagenicity, teratogenicity and carcinogenicity.
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http://dx.doi.org/10.1016/j.mrrev.2008.03.004DOI Listing
September 2008

Distortion of neutron field during mice irradiation at Kinki University reactor UTR-KINKI.

Appl Radiat Isot 2007 Sep 22;65(9):1037-40. Epub 2007 May 22.

Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan.

A dosimetry study of mice irradiation at the Kinki University nuclear reactor (UTR-KINKI) has been carried out. Neutron and gamma-ray doses at the irradiation port in the presence of 0, 1, 2, 4 and 6 mice were measured using the paired chamber method. The results show that neutron dose is reduced with increasing numbers of mice. In the six-mice irradiation condition, neutron dose is about 15% smaller compared to a case where no mice were placed in the irradiation port. To investigate the distortion of the neutron spectrum during mice irradiation at UTR-KINKI, a Monte Carlo calculation using the MCNP4C code has been carried out. The measured variation in dose with respect to the total mouse mass was closely reproduced by the calculation results for neutron and gamma-ray dose. Distortion of the neutron spectrum was observed to occur between 1 keV and 1 MeV.
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http://dx.doi.org/10.1016/j.apradiso.2007.04.018DOI Listing
September 2007

Down-regulation of insulin-like growth factor binding protein-5 (IGFBP-5): novel marker for cervical carcinogenesis.

Int J Cancer 2007 May;120(10):2068-77

Department of Obstetrics and Gynecology, Osaka University Graduate School of Medicine, 1-1 Yamada-oka, Suita, Osaka 565-0871, Japan.

To better understand the underlying pathways of cervical carcinogenesis, cDNA microarray analysis was performed on 2 sets of squamous cell carcinomas (SCCs) and their adjacent normal squamous epithelia. Consistently altered expression was detected for 32 genes. Real-time RT-PCR analysis was conducted on a selected subset of these genes (S100A2, GPC4, p72, IGFBP-5, TRIM2 and NAB2) for 14 additional SCCs and 10 normal epithelia. This found that, of the 6 candidate genes, only the insulin-like growth factor binding protein-5 (IGFBP-5) mRNA was generally and significantly under-expressed in SCCs (p < 0.001). All normal cervical epithelia (30 of 30) stained positively for IGFBP-5 protein, with 70% showing strong staining, whereas 65% (17/26) of SCC had complete loss of IGFBP-5, and only 8% (2/26) SCC retained strong expression (p < 0.001). Immunohistochemistry of premalignant cervical intraepithelial neoplasia (CIN) lesions shows a significantly weaker or negative staining in advanced CIN3 lesions compared with normal squamous epithelia (p = 0.001). This is the first study to show that down-regulation of IGFBP-5 protein correlates with cervical carcinogenesis and does so at a preneoplastic stage.
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http://dx.doi.org/10.1002/ijc.22264DOI Listing
May 2007

Transgenerational effects of radiation and chemicals in mice and humans.

Authors:
Taisei Nomura

J Radiat Res 2006 ;47 Suppl B:B83-97

Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan.

Parental exposure of mice to radiation and chemicals causes a variety of adverse effects (e.g., tumors, congenital malformations and embryonic deaths) in the progeny and the tumor-susceptibility phenotype is transmissible beyond the first post-radiation generation. The induced rates of tumors were 100-fold higher than those known for mouse specific locus mutations. There were clear strain differences in the types of naturally-occurring and induced tumors and most of the latter were malignant. Another important finding was that germ-line exposure elicited very weak tumorigenic responses, but caused persistent hypersensitivity in the offspring for the subsequent development of cancer by the postnatal environment. Activations of oncogenes, ras, mos, abl, etc. and mutations in tumor suppressor genes such as p53 were also detected in specific tumors in cancer-prone descendants. However, the majority of tumors observed in the progeny were those commonly observed in the strains that were used and oncogene activations were rarely observed in these tumors. It can be hypothesized that genetic instability modifies tumor occurrence in a transgenerational manner, but so far no links could be established between chromosomal and molecular changes and transmissible tumor risks. Our data are consistent with the hypothesis that cumulative changes in many normal but cancer-related genes affecting immunological, biochemical and physiological functions may slightly elevate the incidence of tumors or fasten the tumor development. This hypothesis is supported by our GeneChip analyses which showed suppression and/or over-expression of many such genes in the offspring of mice exposed to radiation. In humans, a higher risk of leukemia and birth defects has been reported in the children of fathers who had been exposed to radionuclides in the nuclear reprocessing plants and to diagnostic radiation. These findings have not been supported in the children of atomic bomb survivors in Hiroshima and Nagasaki, who were exposed to higher doses of atomic radiation. However, it will be important to follow the human subjects, especially for adult type cancers and chronic diseases throughout their lives to determine whether the mouse studies can predict human responses.
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http://dx.doi.org/10.1269/jrr.47.b83DOI Listing
December 2009

Germ-line mutations at a mouse ESTR (Pc-3) locus and human microsatellite loci.

J Radiat Res 2006 ;47 Suppl B:B31-7

Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan.

We examined the use of the mouse Pc-3 ESTR (expanded simple tandem repeat) locus and 72 human microsatellite loci as potentially sensitive biomarkers for mutagenic exposures to germ cells in mice and humans respectively. In the mouse work, we treated male mice with TCDD (2, 3, 7, 8-tetrachlorodibenzo-p-dioxin; a chemical known to induce congenital anomalies in humans and mice) and, analysed the F(1) fetuses for Pc-3 mutations. Although the incidence of anomalies was higher in the TCDD group, there were no induced mutations. However, respiratory distress syndrome (RDS) was observed in 3 of 7 fetuses born to male mice which were treated with TCDD and which showed abnormal length of Pc-3 allele. In the human studies, the children of Chernobyl liquidators were examined for mutations at a total of 72 (31 autosomal, 1 X-linked and 40 Y-linked) microsatellite loci. This study was prompted by earlier findings of increases in microsatellite mutations in barn swallows and wheat in the highly contaminated areas after the Chernobyl accident. We examined 64 liquidator families (70 children) and 66 control families (70 children). However, no increases in mutation rates were found. The estimated mean dose to the liquidators was about 39 mSv and this might be one possible reason why no increases of mutations could be found.
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http://dx.doi.org/10.1269/jrr.47.b31DOI Listing
December 2009

Gene mutation analysis of sinonasal lymphomas in Indonesia.

Oncol Rep 2006 May;15(5):1257-63

Department of Anatomical Pathology, Faculty of Medicine, University of Indonesia/Dr. Cipto Mangunkusumo Hospital, Jalan Salemba Raya, Jakarta 10430, Indonesia.

Sinonasal lymphomas comprise NK/T-cell (NKTCL) type and B-cell type with unique geographical development. In this study, mutations of p53, K-ras, c-kit, beta-catenin, and bak gene were analyzed using polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) followed by direct sequencing in 41 sinonasal lymphomas (27 NKTCL and 14 B-cell type) from Indonesia. In situ hybridization study with EBER-1 probe revealed that 85% of NKTCL cases were EBV positive, but none of B-cell type was EBV positive. Frequency of mutations in p53, K-ras, c-kit, beta-catenin, and bak gene was 62.9%, 0%, 11.1%, 18.5%, and 25.9%, respectively, in NKTCL, and 71.4%, 0%, 23.1%, 21.4%, and 57.1%, respectively, in B-cell cases, showing that mutation frequency in all genes was higher in B-cell than in NKTCL cases. These findings suggest that gene mutations might be the driving-force for B-cell lymphoma, whereas combined EBV infection and gene mutations contribute to NKTCL development in Indonesia.
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May 2006

Transforming growth factor-beta3 promotes mesenchymal cell proliferation and angiogenesis mediated by the enhancement of cyclin D1, Flk-1, and CD31 gene expression during CL/Fr mouse lip fusion.

Birth Defects Res A Clin Mol Teratol 2005 Dec;73(12):956-65

Graduate School of Dental Science, Kyushu University, Fukuoka, Japan.

Background: Cleft lip with or without cleft palate is the most common congenital anomaly in the craniofacial region. Knowledge of the molecular mechanisms behind normal lip fusion can contribute to better intervention and improved functional clinical outcome. Transforming growth factor-beta3 (TGF-beta3) has been implicated in lip morphogenesis. Therefore, we hypothesized that TGF-beta3 functions during lip fusion through regulation of angiogenesis and mesenchymal cell cycle progression during early developmental stages.

Methods: To test this hypothesis we used the CL/Fraser mouse model, which has a high incidence of cleft lip. Lips isolated from embryonic day (ED) 11.5 mouse embryos were allowed to develop in serum-free organ cultures in the presence or absence of TGF-beta3. The lips that developed in these cultures fused in 2 days.

Results: During normal development, we detected positive immunoreactions for TGF-beta3 at the site of fusion. We also detected mesenchymal cells that were immunopositive for Flk-1 and CD31, which are markers for endothelial cell precursors. Exogenous TGF-beta3 accelerated lip fusion in culture. This enhancement was associated with an increase in the number of capillary blood vessels in the lips cultured in the presence of TGF-beta3, in comparison with controls. In tandem, TGF-beta3 increased the level of expression of both Flk-1 and CD31. Our data suggest that an elevated level of TGF-beta3 may promote angiogenesis in developing lips that is mediated by increased Flk-1 and CD31 expression. We also detected increased cyclin D1 expression (a marker for cell proliferation) in the presence of TGF-beta3, which suggests that TGF-beta3 promoted cell proliferation.

Conclusions: TGF-beta3 promoted cell proliferation and angiogenesis in lip mesenchymal tissues. These events led to enhanced lip fusion in the presence of TGF-beta3.
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http://dx.doi.org/10.1002/bdra.20191DOI Listing
December 2005
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