start-ver=1.4 cd-journal=joma no-vol=313 cd-vols= no-issue=1 article-no= start-page=169 end-page=174 dt-received= dt-revised= dt-accepted= dt-pub-year=2017 dt-pub=201707 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=In vitro analysis of radioprotective effect of monoterpenes en-subtitle= kn-subtitle= en-abstract= kn-abstract= Monoterpenes are naturally occurring hydrocarbons composed of two units of isoprenes. They exhibit antioxidant activity to scavenge reactive oxygen species, such as hydroxyl radicals. We investigated the potential of monoterpenes such as thymol, linalool, and menthol to act as radioprotectants. The proliferation of EL4 cells, a mouse lymphoma cell line, treated with linalool at a concentration of 500 μM or more was not affected by X-ray irradiation. Plasmid-nicking assay performed using formamidopyrimidine-DNA glycosylase showed that linalool prevented single strand breaks and oxidized purines on pUC19 plasmid DNA. These findings indicate that linalool has the ability to scavenge reactive oxygen species and is a potential radioprotector. en-copyright= kn-copyright= en-aut-name=KudoKen-ichi en-aut-sei=Kudo en-aut-mei=Ken-ichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=HanafusaTadashi en-aut-sei=Hanafusa en-aut-mei=Tadashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OnoToshiro en-aut-sei=Ono en-aut-mei=Toshiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil= affil-num=2 en-affil=Department of Radiation Research, Advanced Science Research CenterOkayama University kn-affil= affil-num=3 en-affil=Department of Radiation Research, Advanced Science Research CenterOkayama University kn-affil= en-keyword=Monoterpenes kn-keyword=Monoterpenes en-keyword= Linalool kn-keyword= Linalool en-keyword=X-ray irradiation kn-keyword=X-ray irradiation en-keyword= Reactive oxygen species kn-keyword= Reactive oxygen species en-keyword= SSB kn-keyword= SSB END start-ver=1.4 cd-journal=joma no-vol=71 cd-vols= no-issue=3 article-no= start-page=219 end-page=226 dt-received= dt-revised= dt-accepted= dt-pub-year=2017 dt-pub=201706 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=The Immunological Impact of Chemotherapy on the Tumor Microenvironment of Oral Squamous Cell Carcinoma en-subtitle= kn-subtitle= en-abstract= kn-abstract= Anticancer drugs induce cell-cycle arrest and apoptosis not only in tumor cells, but also in immune cells. However, many preclinical and clinical findings show that some chemotherapeutic agents can improve the antitumor efficacy of immunotherapy. We immunohistochemically analyzed the degree of immune cell infiltration and the relevance of programmed cell death 1 ligand-1 (PD-L1) expression in surgically resected oral squamous cell carcinoma (OSCC) specimens from patients who had undergone pretreatment with certain chemotherapies and other patients without pretreatment. We divided the patients into the group of neoadjuvant chemotherapy (NAC) patients (n=8) and the nNAC (without NAC) patient group (n=10). We observed that NAC induced infiltrations of CD4, CD8 T cells and CD56 NK cells into the tumor microenvironment. Decreased numbers of Tregs and PD-1-positive cells were observed in the NAC group. No significant difference was observed in the degree of immune-cell infiltration between the patient groups except for CD56 NK cells in the stroma and PD-1 cells in cancer nests. Eighty percent of the nNAC specimens showed intermediate-to-strong PD-L1 protein expression, whereas 75% of the NAC specimens showed down-regulation of the PD-L1 protein, indicating the effectiveness of the chemotherapeutic treatment before surgery. en-copyright= kn-copyright= en-aut-name=TakakuraHiroaki en-aut-sei=Takakura en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=DomaeShohei en-aut-sei=Domae en-aut-mei=Shohei kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OnoToshiro en-aut-sei=Ono en-aut-mei=Toshiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=SasakiAkira en-aut-sei=Sasaki en-aut-mei=Akira kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=2 en-affil=Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= affil-num=3 en-affil=Department of Radiation Research, Advanced Science Research Center, Okayama University kn-affil= affil-num=4 en-affil=Department of Oral and Maxillofacial Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences kn-affil= en-keyword=oral squamous cell carcinoma kn-keyword=oral squamous cell carcinoma en-keyword=programmed cell death 1 ligand-1 kn-keyword=programmed cell death 1 ligand-1 en-keyword=tumor microenvironment kn-keyword=tumor microenvironment en-keyword=neoadjuvant chemotherapy kn-keyword=neoadjuvant chemotherapy en-keyword=immunohistochemistry kn-keyword=immunohistochemistry END start-ver=1.4 cd-journal=joma no-vol= cd-vols= no-issue= article-no= start-page= end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2015 dt-pub=20150620 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Adsorption and removal of strontium in aqueous solution by synthetic hydroxyapatite en-subtitle= kn-subtitle= en-abstract= kn-abstract=Hydroxyapatite (HAP) is a main mineral constituent of bone and tooth and has an outstanding biocompatibility. HAP is a possible sorbent for heavy metals in wastewater due to its high adsorption capacity and low water solubility. We developed a removal system of 90Sr from aqueous solution by HAP column procedure. More than 90 % of 90Sr was adsorbed and removed from the 90Sr containing solution. Divalent cations, Ca2+, had little effect on the removal of 90Sr up to a concentration of 1 mmol L−1. This clearly indicates that the HAP column technique is advantageous with respect to the capacity to adsorb 90Sr from water present in the environment. en-copyright= kn-copyright= en-aut-name=NishiyamaYuichi en-aut-sei=Nishiyama en-aut-mei=Yuichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=HanafusaTadashi en-aut-sei=Hanafusa en-aut-mei=Tadashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=YamashitaJun en-aut-sei=Yamashita en-aut-mei=Jun kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=YamamotoYoko en-aut-sei=Yamamoto en-aut-mei=Yoko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=OnoToshiro en-aut-sei=Ono en-aut-mei=Toshiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil= kn-affil=Department of Radiation Research, Advanced Science Research Center, Okayama University affil-num=2 en-affil= kn-affil=Department of Radiation Research, Advanced Science Research Center, Okayama University affil-num=3 en-affil= kn-affil=Institute of Plant Science and Resources, Okayama University affil-num=4 en-affil= kn-affil=Institute of Plant Science and Resources, Okayama University affil-num=5 en-affil= kn-affil=Department of Radiation Research, Advanced Science Research Center, Okayama University en-keyword=Strontium kn-keyword=Strontium en-keyword=Hydroxyapatite kn-keyword=Hydroxyapatite en-keyword=Adsorption kn-keyword=Adsorption en-keyword=Desorption kn-keyword=Desorption en-keyword=Divalent cation kn-keyword=Divalent cation END start-ver=1.4 cd-journal=joma no-vol=301 cd-vols= no-issue=1 article-no= start-page=57 end-page=62 dt-received= dt-revised= dt-accepted= dt-pub-year=2011 dt-pub=20110201 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Isolation and characterization of human lung cancer antigens by serological screening with autologous antibodies en-subtitle= kn-subtitle= en-abstract= kn-abstract=Serological analysis of a recombinant cDNA expression library (SEREX) derived from two lung adenocarcinoma cancer cell lines using autologous sera led to the isolation of 41 positive cDNA clones comprising 28 different antigens. They coded for a variety of nuclear and cytoplasmic proteins. Among the antigens, nucleoporin 107 (NUP107) was isolated most frequently (5 of 41 clones). The second most frequently isolated antigen was coded for by C21orf58 (4 of 41 clones). During serological analysis of selected antigens based on their reactivity to sera from normal individuals and lung cancer patients, none of the antigens showed a cancer-restricted recognition pattern. However, five genes including NUP107 showed higher expression when we examined the changes in gene expression in five different adenocarcinoma cell lines, including those used in SEREX, compared with their levels in normal lung tissues by cDNA microarray analysis. On the other hand, the expression levels of five genes including C21orf58 were down regulated in all adenocarcinoma cell lines. This SEREX study combining comprehensive gene expression assays has added to the growing list of lung cancer antigens, which may aid the development of diagnostic and immunotherapeutic reagents for patients with lung cancer. en-copyright= kn-copyright= en-aut-name=HanafusaTadashi en-aut-sei=Hanafusa en-aut-mei=Tadashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MohamedAli Eldib Ali en-aut-sei=Mohamed en-aut-mei=Ali Eldib Ali kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KitaokaKenta en-aut-sei=Kitaoka en-aut-mei=Kenta kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=OhueYoshihiro en-aut-sei=Ohue en-aut-mei=Yoshihiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=NakayamaEiichi en-aut-sei=Nakayama en-aut-mei=Eiichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=OnoToshiro en-aut-sei=Ono en-aut-mei=Toshiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= affil-num=1 en-affil= kn-affil=Department of Radiation Research, Advanced Science Research Center, Okayama University affil-num=2 en-affil= kn-affil=Faculty of Science, Alexandria University affil-num=3 en-affil= kn-affil=Hyogo Prefectural Awaji Hospital affil-num=4 en-affil= kn-affil=Department of Medicine, Kawasaki Medical University affil-num=5 en-affil= kn-affil=Faculty of Health and Welfare, Kawasaki University of Medical Welfare affil-num=6 en-affil= kn-affil=Department of Radiation Research, Advanced Science Research Center, Okayama University en-keyword=Lung adenocarcinoma kn-keyword=Lung adenocarcinoma en-keyword=SEREX kn-keyword=SEREX en-keyword=Tumor antigen kn-keyword=Tumor antigen en-keyword=NUP107 kn-keyword=NUP107 en-keyword=MYL6B kn-keyword=MYL6B END start-ver=1.4 cd-journal=joma no-vol=65 cd-vols= no-issue=2 article-no= start-page=91 end-page=95 dt-received= dt-revised= dt-accepted= dt-pub-year=2011 dt-pub=201104 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=An Assessment of Radioactivity Levels of 210Pb and 40K in Tobacco and Radiation Exposure from Smoking en-subtitle= kn-subtitle= en-abstract= kn-abstract=No research has been conducted on the radiation influence of tobacco on the alimentary system, although there have been some previous works on the respiratory system. In this study, the radioactive concentrations of 210Pb and 40K in a cigarette sample were first measured. The transfer factors of the nuclides from tobacco into smoke and solution (saliva and/or alcohol) were then examined. Moreover, the radiation doses from smoke inhalation were also evaluated. The radioactive concentrations of 210Pb and 40K in the cigarette tobacco were 0.01 and 0.3 Bq/cigarette. Since this 210Pb activity and the 210Po activity previously reported for the same sample were comparable, it can be concluded that there was a radioactive equilibrium between the 2 nuclides. The observed transfer factor of 210Pb (12%) into smoke was almost the same as that of 40K (15%), whereas the reported value for 210Po (60%) was significantly higher. The radiation doses due to inhalation of cigarette smoke varied from organ to organ, depending on the organotropic properties of the nuclide. For example, the kidneys, respiratory tract, and spleen showed relatively high doses from 210Pb and 210Po. The leaching rates indicated an inconsistent tendency related to solution types. This result could suggest that alcohol drinking, which is common in smokers, does not especially enhance the leaching characteristics. en-copyright= kn-copyright= en-aut-name=NagamatsuTomohiro en-aut-sei=Nagamatsu en-aut-mei=Tomohiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=SakodaAkihiro en-aut-sei=Sakoda en-aut-mei=Akihiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KataokaTakahiro en-aut-sei=Kataoka en-aut-mei=Takahiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=OnoToshiro en-aut-sei=Ono en-aut-mei=Toshiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=YamaokaKiyonori en-aut-sei=Yamaoka en-aut-mei=Kiyonori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil= kn-affil=Graduate School of Health Sciences, Okayama University affil-num=2 en-affil= kn-affil=Graduate School of Health Sciences, Okayama University affil-num=3 en-affil= kn-affil=Graduate School of Health Sciences, Okayama University affil-num=4 en-affil= kn-affil=Department of Radiation Research Shikata Laboratory, Advanced Science Research Center, Okayama University affil-num=5 en-affil= kn-affil=Graduate School of Health Sciences, Okayama University en-keyword=tobacco kn-keyword=tobacco en-keyword=radionuclides kn-keyword=radionuclides en-keyword=smoking kn-keyword=smoking en-keyword=intake kn-keyword=intake en-keyword=radiation exposure kn-keyword=radiation exposure END start-ver=1.4 cd-journal=joma no-vol=48 cd-vols= no-issue=5 article-no= start-page=279 end-page=282 dt-received= dt-revised= dt-accepted= dt-pub-year=1994 dt-pub=199410 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Allergens of the house dust mite, Dermatophagoides pteronyssinus, in patients with mite allergic rhinitis: a clinical investigation by intracutaneous skin tests and nasal provocation tests. en-subtitle= kn-subtitle= en-abstract= kn-abstract=
To determine the allergens of mite allergic rhinitis, we studied 31 patients with mite allergic rhinitis by skin tests and nasal provocation tests (15 for skin and 16 for nasal tests) using 6 fractions of Dermatophagoides pteronyssinus (Dp) extract differing in molecular weights (15, 25, 32, 53, 95 and 190 kDMW). In skin testing, patients showed intense positive reactions to the fractions of 15, 25, 32, 95 and 190 kDMW, among which the most patients showed positive reactions to the fractions of 15 and 25 kDMW. Significant differences were found in patients' positive reactivity among each fraction and between low (15 and 25 kD) and high (95 and 190 kD) molecular weight fractions as well. In nasal provocation tests, patients showed intense positive reactions to the fractions of 15, 32, 53 and 95 kDMW, especially to the fractions of 15 and 95 kDMW. Furthermore, the insidence of positive reactions to the 15 kDMW fraction was significantly higher than that to any other fraction in the skin tests (P < 0.05). From these results, the low molecular weight fraction, 15 kDMW, is considered to be the main allergen of this mite and the high molecular weight fractions, 95 and 190 kDMW, may also be considered to be allergens of this mite.
en-copyright= kn-copyright= en-aut-name=NishiokaKeiko en-aut-sei=Nishioka en-aut-mei=Keiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=SaitoChisato en-aut-sei=Saito en-aut-mei=Chisato kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NaganoToshiaki en-aut-sei=Nagano en-aut-mei=Toshiaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=OkanoMitsuhiro en-aut-sei=Okano en-aut-mei=Mitsuhiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=NakagawaFumio en-aut-sei=Nakagawa en-aut-mei=Fumio kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=NishiokaSatoko en-aut-sei=Nishioka en-aut-mei=Satoko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=MasudaYu en-aut-sei=Masuda en-aut-mei=Yu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=OnoToshiro en-aut-sei=Ono en-aut-mei=Toshiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= affil-num=1 en-affil= kn-affil=Hiroshima City Hospital affil-num=2 en-affil= kn-affil=Okayama City Hospital affil-num=3 en-affil= kn-affil=Okayama Univeristy affil-num=4 en-affil= kn-affil=Okayama Uniiversity affil-num=5 en-affil= kn-affil=Okayama University affil-num=6 en-affil= kn-affil=Okayama University affil-num=7 en-affil= kn-affil=Okayama University affil-num=8 en-affil= kn-affil=Okayama University en-keyword=mite allergen kn-keyword=mite allergen en-keyword=skin test kn-keyword=skin test en-keyword=nasal provoration test kn-keyword=nasal provoration test en-keyword=allergen rhinitis kn-keyword=allergen rhinitis END start-ver=1.4 cd-journal=joma no-vol=48 cd-vols= no-issue=5 article-no= start-page=279 end-page=282 dt-received= dt-revised= dt-accepted= dt-pub-year=1994 dt-pub=199410 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Allergens of the house dust mite, Dermatophagoides pteronyssinus, in patients with mite allergic rhinitis: a clinical investigation by intracutaneous skin tests and nasal provocation tests. en-subtitle= kn-subtitle= en-abstract= kn-abstract=To determine the allergens of mite allergic rhinitis, we studied 31 patients with mite allergic rhinitis by skin tests and nasal provocation tests (15 for skin and 16 for nasal tests) using 6 fractions of Dermatophagoides pteronyssinus (Dp) extract differing in molecular weights (15, 25, 32, 53, 95 and 190 kDMW). In skin testing, patients showed intense positive reactions to the fractions of 15, 25, 32, 95 and 190 kDMW, among which the most patients showed positive reactions to the fractions of 15 and 25 kDMW. Significant differences were found in patients' positive reactivity among each fraction and between low (15 and 25 kD) and high (95 and 190 kD) molecular weight fractions as well. In nasal provocation tests, patients showed intense positive reactions to the fractions of 15, 32, 53 and 95 kDMW, especially to the fractions of 15 and 95 kDMW. Furthermore, the insidence of positive reactions to the 15 kDMW fraction was significantly higher than that to any other fraction in the skin tests (P < 0.05). From these results, the low molecular weight fraction, 15 kDMW, is considered to be the main allergen of this mite and the high molecular weight fractions, 95 and 190 kDMW, may also be considered to be allergens of this mite.
en-copyright= kn-copyright= en-aut-name=NishiokaKeiko en-aut-sei=Nishioka en-aut-mei=Keiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=SaitoChisato en-aut-sei=Saito en-aut-mei=Chisato kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NaganoToshiaki en-aut-sei=Nagano en-aut-mei=Toshiaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=OkanoMitsuhiro en-aut-sei=Okano en-aut-mei=Mitsuhiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=NakagawaFumio en-aut-sei=Nakagawa en-aut-mei=Fumio kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=NishiokaSatoko en-aut-sei=Nishioka en-aut-mei=Satoko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=MasudaYu en-aut-sei=Masuda en-aut-mei=Yu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=OnoToshiro en-aut-sei=Ono en-aut-mei=Toshiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= affil-num=1 en-affil= kn-affil=Hiroshima City Hospital affil-num=2 en-affil= kn-affil=Okayama City Hospital affil-num=3 en-affil= kn-affil=Okayama Univeristy affil-num=4 en-affil= kn-affil=Okayama University affil-num=5 en-affil= kn-affil=Okayama University affil-num=6 en-affil= kn-affil=Okayama University affil-num=7 en-affil= kn-affil=Okayama University affil-num=8 en-affil= kn-affil=Okayama University en-keyword=mite allergen kn-keyword=mite allergen en-keyword=skin test kn-keyword=skin test en-keyword=nasal provoration test kn-keyword=nasal provoration test en-keyword=allergen rhinitis kn-keyword=allergen rhinitis END start-ver=1.4 cd-journal=joma no-vol=5 cd-vols= no-issue= article-no= start-page= end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2005 dt-pub=20050120 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Functional promoter upstream p53 regulatory sequence of IGFBP3 that is silenced by tumor specific methylation en-subtitle= kn-subtitle= en-abstract= kn-abstract=Background: Insulin-like growth factor binding protein (IGFBP)-3 functions as a carrier of insulinlike
growth factors (IGFs) in circulation and a mediator of the growth suppression signal in cells. There are two reported p53 regulatory regions in the IGFBP3 gene; one upstream of the promoter and one intronic. We previously reported a hot spot of promoter hypermethylation of IGFBP-3 in
human hepatocellular carcinomas and derivative cell lines. As the hot spot locates at the putative upstream p53 consensus sequences, these p53 consensus sequences are really functional is a question to be answered.
Methods: In this study, we examined the p53 consensus sequences upstream of the IGFBP-3 promoter for the p53 induced expression of IGFBP-3. Deletion, mutagenesis, and methylation
constructs of IGFBP-3 promoter were assessed in the human hepatoblastoma cell line HepG2 for promoter activity.
Results: Deletions and mutations of these sequences completely abolished the expression of IGFBP-3 in the presence of p53 overexpression. In vitro methylation of these p53 consensus
sequences also suppressed IGFBP-3 expression. In contrast, the expression of IGFBP-3 was not affected in the absence of p53 overexpression. Further, we observed by electrophoresis mobility
shift assay that p53 binding to the promoter region was diminished when methylated.
Conclusion: From these observations, we conclude that four out of eleven p53 consensus sequences upstream of the IGFBP-3 promoter are essential for the p53 induced expression of
IGFBP-3, and hypermethylation of these sequences selectively suppresses p53 induced IGFBP-3 expression in HepG2 cells.