bluuebunny/crossref_metadata_2025 huggingface dataset:
Pendolmycin, a New Tumor Promoter of the Teleocidin A Class on Skin of CD‐1 Mice
Authors: Nishiwaki Shinji , Fujiki Hirota , Yoshizawa Seiji , Suganuma Masami , Furuya‐Suguri Hiroko , Okabe Sachiko , Nakayasu Michie , Okabe Kazuaki , Muratake Hideaki , Natsume Mitsutaka , Umezawa Kazuo , Sakai Shin‐ichiro , Sugimura Takashi
Published: August 2005

Pendolmycin, isolated from Nocardiopsis, is a compound structurally similar to teleocidin A, one of the 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA)‐type tumor promoters. Pendolmycin has a C5 dimethyl allyl group attached to C‐7 of (‐)‐indolactam‐V, whereas teleocidin A has a C10 linalyl group attached to the molecule. The structure‐activity relationships of a hydrophobic moiety attached to (‐)‐indolactam‐V were studied in four compounds, (‐)‐indolactam‐V, pendolmycin, teleocidin A and newly synthesized 7‐(nerolidyl)‐(‐)‐indolactam‐V in tests on inhibition of the specific [3H]TPA binding to a particulate fraction of mouse skin, activation of protein kinase C and induction of both adhesion of HL‐60 cells and ornithine decarboxylase in mouse skin. The potencies of the compounds for these activities increased mainly depending on the length of the hydrophobic group. Pendolmycin had a tumor‐promoting activity on mouse skin initiated with a single application of 7,12‐dimethyl‐benz[a]anthracene, and its potency was just between those of (‐)‐indolactam‐V and teleocidin A. The role of the hydrophobic moiety is discussed with particular emphasis on the results obtained with 7‐(nerolidyl)‐(‐)‐indolactam‐V.
Induction of Glutathione S‐Transferase P‐Form in Primary Cultured Rat Hepatocytes by Epidermal Growth Factor and Insulin
Authors: Hatayama Ichiro , Yamada Yuichi , Tanaka Keiji , Ichihara Akira , Sato Kiyomi
Published: August 2005

The effects of epidermal growth factor (EGF) (10 ng/ml) and insulin (100 nM) on the expression of glutathione S‐transferases (GSTs), especially the GST‐P form (GST 7–7), were examined in primary cultured rat hepatocytes in serum‐free medium. On culture with EGF and insulin, the GST activities towards l‐chloro‐2,4‐dinitrohenzene and l,2‐dichloro‐4‐nitrobenzene were transiently decreased on day 2 to 10% of those of freshly isolated hepatocytes and then increased to 60 to 100% of those of freshly isolated cells on day 4. Western hlot analysis of GSTs revealed that GST‐P, which is not present in freshly isolated hepatocytes, was markedly induced and that GST subimits 3 and 4 of the Mu class also increased after addition of EGF and/or insulin, while the subunits 1 and 2 of the Alpha class disappeared. Northern blot analysis showed that on addition of EGF and insulin the level of GST‐P mRNA was also elevated and expressions of the nuclear oncogenes c‐jun and c‐fos were enhanced. These results suggest that the enhanced expression of GST‐P induced by EGF or insulin in primary cultured rat hepatocytes might he regulated by JUN and FOS proteins.
Primer‐dependent Amplification of mdr1 mRNA by Polymerase Chain Reaction
Authors: Sugawara Isamu , Watanabe Masatoshi , Masunaga Atsuko , Itoyama Shinji , Ueda Kazumitsu
Published: August 2005

We have developed a sensitive reverse transcription (RT)‐polymerase chain reaction (PCR) to evaluate multidrug resistance in various tissues, using seven mdr‐specific primer sets, mdr1 mRNA expression was noted in 16/197 samples. However, the apparent degree of mdr1 mRNA expression depended on the sequence of the primers employed. These findings suggest that more than two sets of primers should he used for effective RT‐PCR.
A Case‐Control Study on Occupational Lung Cancer Risks in an Industrialized City of Japan
Authors: Yamaguchi Naohito , Kido Masamitsu , Hoshuyama Tsutomu , Manabe Hideo , Kikuchi Yutaka , Nishio Tetsuo , Ohshima Li Hwa K. , Watanabe Shaw
Published: August 2005

A hospital‐based case‐control study was conducted to evaluate occupational risks of lung cancer in an industrialized city of Japan. The lung cancer cases were obtained from 3 major hospitals in the city. The control group consisted of patients with a variety of diseases hospitalized in the same wards of the same hospitals as the cases. After matching on sex, 5–year age category and hospital, 144 cases and 676 controls comprised the study group. A self‐administered questionnaire was used to obtain lifetime job histories and smoking status. The conditional logistic regression model was used to estimate relative risks after controlling for smoking and employment in other jobs. The workers in shipbuilding, ironworks and other plants (mostly chemical plants) showed statistically significant increases in lung cancer risk with relative risks of 6.18, 2.02, and 2.66, respectively. An increase in risk with the duration of employment was also observed in the “other plants” category. Building and road construction workers also showed increased relative risks, 1.95 and 1.79, but they were not significant. When the risk was evaluated on the exposure chemicals, the workers exposed to inorganic acids and bases had significantly increased risk. The workers exposed to asbestos, dust or organic chemicals also showed increased risk but the effects were not significant. The combined effect of smoking and employment in ironworks showed a good fit to an additive model, while that in the “other plants” category was closer to a multiplicative model.
Diagnostic Validity of Fecal Occult Blood Tests for Detecting Gastroenterological Cancers
Authors: Murakami Ryosuke , Otani Torn , Nakanishi Katsumi , Fudemoto Yoshiyuki , Ishikawa Hideki , Hiyama Tomohiko , Tsukuma Hideaki , Fujimoto Isaburo , Miki Nobuo , Oshima Akira
Published: August 2005

In order to estimate the diagnostic validity of chemical fecal occult blood tests, i.e. orthotolidine (Shionogi A) and guajac (Shionogi B) slides for detecting cancers of the esophagus, stomach and colorectum, the authors followed up all the examinees (n=3,449) of comprehensive medical check‐ups at the Center for Adult Diseases, Osaka, by means of record linkage to the Osaka Cancer Registry's files. Then, diagnostic validity was calculated based on the results of two years’ follow‐up. Sensitivity for the respective cancers was 20.0%, 11.8% and 62.5% for Shionogi A, and 20.0%, 5.9% and 43.8% for Shionogi B slides. Likelihood ratio for the respective cancers was 1.4, 0.8 and 4.5 for Shionogi A, and 3.3, 1.0 and 7.5 for Shionogi B. Specificity was analogous among the three cancer sites, being 86% for Shionogi A and 94% for Shionogi B. These results suggest that the diagnostic validity of chemical occult blood tests for detecting cancers of the esophagus and the stomach is very poor, and therefore imply that close examinations of these sites for screening positives is unnecessary in mass screenings for colorectal cancer.
High Susceptibility of Analbuminemic Rats to Neurogenic Tumor Induction by Transplacental Administration of N‐Ethyl‐N‐nitrosourea
Authors: Usuki Seigou , Maekawa Akihiko , Kang Ho‐il , Shumiya Seigo , Nagase Sumi
Published: August 2005

The susceptibilities of Nagase analbuminemic rats (NAR) and control Sprague‐Dawley rats (SDR) to N‐ethyl‐N‐nitrosourea (ENU) were compared. In Experiment I, the rats were given daily subcutaneous injections of 10 mg/kg of ENU for a week from 4 weeks of age. In Experiment II, mother rats were given a single subcutaneous injection of 60 mg/kg of ENU on day 17 of pregnancy and tumor development in their offspring was examined. In Experiment I, the incidence of neurogenic tumors was slightly, but not significantly, higher in NAR than in control rats. In Experiment II, the incidence of total tumors including neurogenic tumors was significantly higher in NAR (40/43, 93.0%) than in SDR (13/61, 21.3%). NAR showed particularly high susceptibility to induction of nenrogenic tumors (34/43, 79.1%) and renal tumors (15/43, 34.9%). In an attempt to elucidate the underlying mechanisms of the increased susceptibility of NAR to ENU, O6‐ethylguanine, a major premutagenic ethylated DNA adduct, was quantitated in fetal brain DNA of NAR and SDR after a pulse exposure to 60 mg/kg ENU. No significant difference in the initial formation or subsequent repair of O6‐ethylguanine was observed in the two strains, indicating that abnormality at some later stage(s) of chemical carcinogenesis may lead to the increased susceptibility of NAR to induction of neurogenic tumors.
Length of Telomeric Repeats in Neuroblastoma: Correlation with Prognosis and Other Biological Characteristics
Authors: Hiyama Eiso , Hiyama Keiko , Yokoyama Takashi , Ichikawa Toru , Matsuura Yuichiro
Published: August 2005

Telomeres are the physical ends of eukaryotic chromosomes. In view of reports of the reduction of telomeric repeats in human malignant tumors, we measured the lengths of telomeric repeats in 55 primary neuroblastomas. The average lengths of telomeric repeats in these tumors fell in a wide range (from 1.1 kb to more than 23 kb) relative to those in ganglioneuromas and normal peripheral mononuclear cells. The reduction of telomeric repeats was significantly correlated with advanced stages of tumor development, poor prognosis, and increased S‐phase fractions in tumor cells. On the other hand, three cases of Stage IV‐S tumors showed the reduction of telomeric repeats and low percentage of S‐phase fractions. These Stage IV‐S patients had a good prognosis with spontaneous regression of metastatic tumors.
Tumor‐specific T Cell Lines: Capacity to Proliferate and Produce Interleukin 2 in Response to Various Forms of Tumor Antigens
Authors: Shimizu Jun , Suda Takashi , Katagiri Tatsuo , Fujiwara Hiromi , Hamaoka Toshiyuki
Published: August 2005

Anti‐tumor proliferative T cell lines were established from cultures of lymph node cells from BALB/c mice immunized to syngeneic CSAIM fibrosarcoma with the CSAIM tumor cell membrane. The cultures were maintained throughout in the absence of exogenous interleukin 2 (IL2) J. Cell surface phenotypes of all T cell lines established were Thy‐1+, Ig‐, L3T4+ and Lyt‐2‐. Their proliferation was induced in a tumor antigen dose‐dependent fashion and a tumor antigen‐specific way. Such proliferative responses were inhibited by the addition to cultures of anti‐class II H‐2d (anti‐I‐Ad) or anti‐L3T4 but not of anti‐class I H‐2d or anti‐Lyt‐2 monoclonal antibody. None of the T cell lines exhibited any cytotoxic T lymphocyte activity but they all produced IL2 upon stimulation with CSAIM tumor antigens, indicating that they represent helper‐type T cell (Th) lines. The activation of these tumor‐specific Th lines was induced with either CSAIM tumor cells themselves, or their membrane or detergent‐solubilized fraction depending on the presence of antigen‐presenting cells (APC). Most importantly, activation was also inducible by membranous tumor antigen‐pulsed APC, which were capable of producing potent anti‐tumor protective immunity when administered in vivo into syngeneic BALB/c mice. These results indicate that the tumor‐specific Th lines established here can be activated with various forms of tumor antigens for their expression of helper function. Since Th lines of this type have not been described previously, our Th lines provide an intriguing tool for investigating the cellular and molecular mechanisms by which tumor‐specific Th recognize tumor antigens.
Enhancement of the Cytotoxicity of Cytosine Arabinoside by Interleukin‐3
Authors: Tanaka Masao
Published: August 2005

We have evaluated the feasibility of enhancing the cytotoxic effect of cytosine arabinoside (ara‐C) on acute myeloid leukemia (AML) cells by increasing the proliferative activity with hematopoietic growth factors. Leukemic cells from 8 persons with AML were tested. Preincubation with interleukin (IL)‐3 (5 U/ml) for 3 days increased DNA synthesis as measured by tritiated thymidine incorporation and Ki67 expression in cells from 7 out of 8 persons with AML, Leukemic cells preincubated with IL‐1 (10 U/ml) or IL‐3 (5 U/ml) were subsequently exposed to ara‐C (3μg/ml) for the final 24 h and the activity of ara‐C against clonogenic acute myeloid leukemia cells was evaluated in terms of the inhibition of colony formation in semisolid media. The exposure to ara‐C inhibits the proliferation of a higher proportion of clonogenic cells in culture pretreated with IL‐3 than in control or cells pretreated with IL‐1. The enhanced cytotoxic effect of ara‐C in the cells pretreated with IL‐3 correlated with increased formation of intracellular ara‐CTP. IL‐3‐induced recruitment of quiescent blasts into the proliferative compartment will lead to increased formation of ara‐CTP in the cells, which would result in an enhanced leukemia cell kill.
Interaction of the Tumor Inhibitor IKP‐104, a 4(1H)‐Pyridinone Derivative, with Microtubule Proteins
Authors: Mizuhashi Fukutaro , Murata Kyoji , Kitagaki Tadaharu , Tomita Isao
Published: August 2005

The effects of a mitotic arrestant, IKP‐104, which has an antitumor activity, on the in vitro., polymerization and depolymerization of rat brain microtubules were investigated. IKP‐104 inhibited microtubule polymerization at concentrations greater than 0.71 × 10‐6M.,a nd its IC50 value was determined to be 1.31 × 10‐6 M by probit analysis. Fifty‐two percent of pre‐polymerized microtubules depolymerized at 1.31 × 10‐6M IKP‐104. Electron micrographs of microtubules taken immediately after treatment with 1 × 10‐3M IKP‐104 revealed a fraying of microtubule ends into elongated coil‐like filaments, which were composed of 2 or 3 protofilaments. When microtubule protein treated with 1 × 10‐3M IKP‐104 was cleaved by trypsin, fragments of 41,36, 34, 23,21,19 and 16 kilodaltons (kDa) derived from a‐tubulin were produced. In particular, the 19, 23 and 34 kDa fragments were characteristically observed in the trypsin cleavage of microtubules treated with IKP‐104, and these fragments were not observed with untreated microtubules. The effects of IKP‐104 on microtubule protein mentioned above were mostly similar to those of vinblastine (VLB) and we suggest that IKP‐104 bound to the site or sites near “VLB‐binding site or sites” of α‐tubulin subunit, resulting in induction of conformational changes.
Characterization of Acquired Resistance to cis‐Diamminedichloroplatinum(II) in Mouse Leukemia Cell Lines
Authors: Tashiro Tazuko , Sato Yuko
Published: August 2005

We have established in vivo cisplatin‐resistant mouse leukemia cell lines, L‐1210/DDP and P388/ DDP, in order to elucidate the mechanism of acquired resistance to cisplatin. Resistance indices were 22 and 14, respectively, when the cells were exposed to cisplatin for 48 h. Uptake of cisplatin by both resistant lines was significantly reduced, compared with values for the respective parent lines (17% for L‐1210/DDP and 27% for P388/DDP, at 100 μM for 1 h). While glutathione contents in the resistant cells were 1.7‐1.9 times higher than those in the sensitive ones, their reduction by preincubation with buthionine sulfoximine did not influence the sensitivity of the cells to cisplatin. In addition, the resistant lines dill not show lower sensitivity to CdCl2, than the respective sensitive ones, suggesting that intracellular SH groups might contribute little to the mechanism of cisplatin resistance in these cells. Postincubation with DNA repair inhibitors, caffeine and aphidicolon, did not selectively enhance the sensitivity of the resistant cells to cisplatin. These results suggested that reduced drug uptake would be a primary mechanism of cisplatin resistance in L‐1210/DDP and P388/DDP. Cross‐resistance patterns to platinum complexes were quite different between L‐1210/DDP and P388/DDP. Colon 26/DDP, another cisplatin‐resistant mouse tumor showed a different pattern from those observed with L‐1210/DDP and P388/DDP. In the development of new platinum complexes we should use plural resistant lines for examining cross‐resistance patterns to candidate platinum complexes.
Infrequent Mutation of p53 Gene in Human Renal Cell Carcinoma Detected by Polymerase Chain Reaction Single‐strand Conformation Polymorphism Analysis
Authors: Suzuki Yasushi , Tamura Gen , Satodate Ryoichi , Fujioka Tomoaki
Published: August 2005

Mutation of the p53 gene, which plays an important role in the genesis of diverse human cancers, was investigated in 23 surgical specimens of human renal cell carcinoma using the polymerase chain reaction single‐strand conformation polymorphism method of analysis. Only one of the 23 tumors (4.3%) carried a mutated p53 gene, which was present in exons 7–8. Direct DNA sequencing confirmed a point mutation at codon 276 (GCC to CCC) resulting in a substitution of alanine for proline. No specific clinicopathological characteristics were observed in the case with the p53 gene mutation in human renal cell carcinoma. These observations suggest that mutation of the p53 gene is rare and thus does not contribute significantly to the genesis of this tumor.
Antitumor Activity of Synthetic Oligonucleotides with Sequences from cDNA Encoding Proteins of Mycobacterium bovis BCG
Authors: Kataoka Tetsuro , Yamamoto Saburo , Yamamoto Toshiko , Kuramoto Etsuro , Kimura Yoshimitsu , Yano Osamu , Tokunaga Tohru
Published: August 2005

Thirteen kinds of 45‐mer or 30‐mer synthetic oligonucleotides with sequences randomly selected from the cDNA encoding three kinds of protein of Mycobacterium bovis BCG were tested for their antitumor activity in a murine tumor system. Six out of the 13 single‐stranded oligonucleotides which contained one or more hexameric palindromic sequences showed strong antitumor activity while the others without palindromic structure did not. Namely, repeated intralesional injections of 100 μg of the 6 oligonucleotides caused regression of the established tumor but the other 7 were ineffective. When tumor cells were mixed with 100 μg of an effective oligonucleotide and injected into mice, tumor growth was markedly suppressed. These results suggested that palindromic structure is essential for the antitumor activity of the synthetic oligonucleotides.
Spontaneous Follicular Center Cell Lymphomas of B Cell Origin in Cataract Mice
Authors: Hayashi Shim‐mo , Nonoyama Takashi , Miyajima Hiroaki
Published: August 2005

Spontaneous lymphomas from a strain of hereditary cataract (CAC‐nct/+) mice were examined by light and electron microscopy and by immunohistochemical reaction for the mouse heavy and light immunoglobulin chains. Lymphomas occurred in 28 out of 45 male cataract mice and in 34 out of 52 females at 25 to 65 weeks of age. All of the lymphoma‐bearing mice showed an enlargement of the spleen and mesenteric lymph nodes, and some mice also had hepatomegaly. Morphologically, all tumors were composed of a mixed population of small and large cells. Neoplastic cells had features of follicular center cell lymphomas, such as scant to moderate amounts of cytoplasm and cleaved and/or round nuclei with a large nuclear‐to‐cytoplasmic ratio. Large cells were often admixed with small cells, and had vesicular nuclei with prominent nucleoli juxtaposed to the nuclear membrane. Intracytoplasmic eosinophilic inclusions were observed in occasional cells, but Golgi apparatus was poorly developed and rough‐surfaced endoplasmic reticulum was scant, unlike those in plasma cells. C‐particles were seen in all lymphoma‐bearing mice by electron microscopy. Intracisternal A‐particles were detected in some mice. Immunohistochemically, neoplastic lymphoid cells were positive for the kappa light chain and the surface/cytoplasmic immunoglobulin M. These results indicate that lymphoid cell neoplasms found in hereditary cataract mice originate from follicular center B cells.
Histopathological and Immunohistochemical Study of Atypical Lymphoid Hyperplasia and Benign Lymphoid Hyperplasia of the Stomach
Authors: Takano Yasuo , Kato Yo , Sugano Haruo
Published: August 2005

We propose dividing histologically reactive lymphoid hyperplasia (RLH) of the stomach into two categories: atypical lymphoid hyperplasia (ALH), characterized by abnormal follicular architecture and infiltration of atypical lymphoid cells, and benign lymphoid hyperplasia (BLH), where normal follicular patterns are preserved and no atypical cells are found. Using twenty RLH cases (10 ALHs and 10 BLHs), both categories were compared front histopathological and immunohistochemical aspects. Macroscopic division into superficial, thick‐walled and nodular types revealed most ALH (80%) to be superficial in character whereas in BLH superficial and thick‐walled types were almost equally represented. Lesion size tended to be larger in ALH (> 6.1 cm) than in BLH (6.0 cm >) cases. As for prognosis after gastrectomy, both categories were favorable. On immunohistochemistry, ALH tended to be strongly labeled by B lymphocyte markers as compared to BLH, where only a weakly positive reaction was expressed. Infiltration of cells labeled by T lymphocyte markers was less conspicuous in ALH than in BLH. From these data, we concluded that ALH and BLH are two distinctive categories of lesion and that ALH has characteristics similar to these demonstrated by malignant lymphoma.
Short Sequence in LI Region of Human Papillomaviruses Correlates with Clinical Pictures and Grouping by Cross‐hybridization
Authors: Iwamoto Aikichi , Yoshikawa Hiroyuki , Kitagawa Kyoko , Igarashi Hiroko , Kawana Takashi , Yoshikura Hiroshi
Published: August 2005

A consensus primer‐mediated polymerase chain reaction devised to amplify a short sequence in LI region (L1‐PCR) efficiently detected genital human papillomaviruses (HPVs) in clinical materials. Nucleotide sequencing of the amplified fragment showed that L1‐PCR is also applicable to hitherto unsequenced HPVs. By comparing the amplified 210 nucleotides HPVs were classified into six groups, which are consistent with clinical pictures and a grouping based on cross‐hybridization under the stringent condition.
A Novel Tetracyclic Peptide, Trapoxin, Induces Phenotypic Change from Transformed to Normal in sis‐Oncogene‐transformed NIH3T3 Cells
Authors: Yoshida Hiroshi , Sugita Kenji
Published: August 2005

A novel tetra cyclic peptide, trapoxin [cyclo(L‐phenylalanyl‐L‐phenylalanyl‐D‐pipecolinyl‐L‐2‐amino‐8‐oxo‐9,10‐epoxy‐decanoyl)], was found to induce the flat phenotype in v‐sis‐transformed NIH3T3 cells at a quite low concentration of 1 ng/ml. Actin stress fiber could be detected after trapoxin treatment. Almost complete reversion into the flat phenotype was observed at 6 h after the administration of the compound. The effect of trapoxin was reversible, when the cell culture was incubated for more than 24 h after its removal. The intracellular level of sis‐mRNA did not decrease with trapoxin treatment at a concentration (50 ng/ml), sufficient to reverse the transformed morphology. Substitution of pipecolinic acid with proline in trapoxin did not change the activity. WF3161, in which leucine was substituted for a phenylalanine of trapoxin, showed only one‐sixteenth of the activity of trapoxin. Reduction of the epoxide residue of trapoxin destroyed the activity.
Illiteracy, Ignorance, and Willingness to Quit Smoking among Villagers in India
Authors: Gavarasana Satyanarayana , Gorty Prasad V. S. N. R. , Allam Apparao
Published: August 2005

During the field work to control oral cancer, difficulty in communication was encountered with illiterates. A study to define the role of illiteracy, ignorance and willingness to quit smoking among the villagers was undertaken in a rural area surrounding Doddipatla Village, A.P., India. Out of a total population of 3,550, 272 (7.7%) persons, mostly in the age range of 21–50 years, attended a cancer detection camp. There were 173 (63.6%) females and 99 (36.4%) males, among whom 66 (M53 + F13) were smokers; 36.4% of males and 63% of females were illiterate. Among the illiterates, it was observed that smoking rate was high (56%) and 47.7% were ignorant of health effects of smoking. The attitude of illiterate smokers was encouraging, as 83.6% were willing to quit smoking. Further research is necessary to design health education material for 413.5 million illiterates living in India (1991 Indian Census). A community health worker, trained in the use of mass media coupled with a person‐to‐person approach, may help the smoker to quit smoking.
Ubiquitous Presence in Mammalian Cells of Enzymatic Activity Specifically Cleaving 8‐Hydroxyguanine‐containing DNA
Authors: Yamamoto Fuyumi , Kasai Hiroshi , Bessho Tadayoshi , Chung Myung‐Hee , Inoue Hideo , Ohtsuka Eiko , Hori Tomokatsu , Nishimura Susumu
Published: August 2005

Here we report the finding of enzymatic activity that specifically cleaves DNA containing 8‐hydroxyguanine (oh8Gua) residues in various mammalian cells. To detect this activity, we used a synthetic double‐stranded DNA containing a single oh8Gua at a defined position as the substrate, and analyzed the products of enzymatic digestion by polyacrylamide gel electrophoresis. Two cleavage sites near the oh8Gua residue were detected with partially purified fractions from cow brain and rat liver, and also with preparations from all mammalian tissues examined. These results suggest that enzymatic activity for the removal of oh8Gua from DNA is widely distributed in mammalian cells.
Augmentation by Bispecific F(ab′)2 Reactive with P‐Glycoprotein and CD3 of Cytotoxicity of Human Effector Cells on P‐Glycoprotein Positive Human Renal Cancer Cells
Authors: Heike Yuji , Okumura Ko , Tsuruo Takashi
Published: August 2005

A bispecific F(ba′)2 was constructed that was composed of two Fab fragments, one derived from anti‐CD3 monoclonal antibody (mAb) (OKT3) and the other from anti P‐glycoprotein mAb (MRK 16). This bispecific F(ab′)2 enhanced the binding and cytotoxicity of human peripheral blood mononuclear cells (PBMCs) on P‐glycoprotein‐positive human kidney cancer cells (ADMHK/E). It had no effect on the cytotoxicity of PBMCs on P‐glycoprotein‐negative HK/E cells [long‐term cultured HK/E (LCHK/E)]. Control F(ab′)2 composed of OKT3 or MRK16 alone did not influence the cytotoxicity of PBMCs on ADMHK/E cells. These findings suggest that the MRK16‐OKT3 bispecific F(ab′)2 may be therapeutically beneficial in treatment of human multidrug‐resistant cancers.
Dose Dependence of N‐Hydroxy‐3,2′‐dimethyM‐aminobiphenyl‐induced Rat Prostate Carcinogenesis
Authors: Shirai Tomoyuki , Iwasaki Shogo , Naito Hatsumi , Masui Tsuneo , Kato Toshio , Imaida Katsumi
Published: August 2005

Groups of F344 rats were administered biweekly intraperitoneal injections of N‐hydroxy‐3,2′‐dimethyl‐4‐aminobiphenyl (N‐OH‐DMAB) at a dose of 5, 10 or 20 mg/kg body weight or DMAB, the parent compound, at a dose of 25 mg/kg body weight, for a total of 10 times. Prostate carcinomas in the ventral lobe developed in a N‐OH‐DMAB dose‐dependent manner (0, 17.6 and 66.7%, respectively) with limited tumor yields in other organs. Although intraperitoneal administration of DMAB was similarly found to induce prostate tumors, it also caused severe chemical peritonitis, which resulted in a high mortality. The present data confirmed that intraperitoneal administration of N‐OH‐DMAB provides a relatively specific induction method for models of prostate carcinogenesis.
Identification of Antibodies against Human Papillomavirus Type 16 E6 and E7 Proteins in Sera of Patients with Cervical Neoplasias
Authors: Sasagawa Toshiyuki , Inoue Masaki , Tanizawa Osamu , Yutsudo Masuo , Hakura Akira
Published: August 2005

We have developed a sensitive and specific ELISA method using the s10‐fusion proteins of human papillomavirus (HPV) 16 E6 and E7, expressed in E, coli. Sera from 97 women (30 patients with invasive cervical cancers, 26 patients with cervical intraepithelial neoplasia III (CIN III) and 38 healthy women) were tested for the presence of antibodies to E6 and E7 proteins. Eight (27%) of the 30 cervical cancer sera, five (19%) of the 26 CIN sera and none of the 38 normal sera were reactive with E6 proteins (cut‐off point: absorbance (A)= 0.59, x + 3SD). Ten (33%) of the 30 cervical cancer sera, two (8%) of the 26 CIN III sera and none of the 38 normal sera were reactive with E7 proteins (cut‐off point: A = 0.40, x + 3SD). The mean absorbance for anti‐E7 antibody in positive cases was higher in cancer patients than in CIN III patients, while that for E6 did not differ between these two groups. Interestingly, six (50%) of 12 cancer sera which reacted with either E6 or E7 proteins were reactive for both proteins, whereas none of the sera from the CIN III patients reacted with both proteins. The high prevalence rates and high absorbance values for HPV 16 E6 and E7 antibodies in association with malignant transformation suggest that detection of these antibodies may be a useful diagnostic aid for cervical cancer‐associated HPV 16.
Differential Expression of Subspecies of Polyomavirus and Murine Leukemia Virus Enhancer Core Binding Protein, PEBP2, in Various Hematopoietic Cells
Authors: Satake Masanobu , Inuzuka Manabu , Shigesada Katsuya , Oikawa Tsuneyuki , Ito Yoshiaki
Published: August 2005

The core sequence of the enhancer of murine leukemia virus (MuLV) long terminal repeat is highly conserved in a large number of MuLV strains and appears to play an essential role when SL3‐3 or Moloney strains induce T cell lymphoma in mice. We found by using the electrophoretic mobility shift assay that a polyomavirus enhancer core‐binding protein, PEBP2, bound to this core motif of MuLV. We also noted that PEBP2 in several hematopoietic cell lines derived from B lymphocyte, macrophage and myelocyte lineages migrated significantly faster than the authentic PEBP2 detected in NIH3T3 (ibroblasts. Interestingly, PEBP2 detected in the cell lines of T lymphocyte lineage appeared to contain both types, which were indistinguishable in electrophoretic mobility from those of NIH3T3 and of B lymphocyte, macrophage and myelocyte lineages. The treatment of the nuclear extract containing PEBP2 with phosphatase generated PEBP3, which is a subcomponent of PEBP2 and retained the same DNA‐binding specificity as PEBP2. The altered mobility of hematopoietic cell‐derived or T lymphocyte‐derived PEBP2 was found to be due to the alteration of the mobility of PEBP3. Based on the distinct mobility of PEBP2/3 of T lymphocytes from those of other hematopoietic cells, we discuss the implication of PEBP2 in MuLV‐induced T cell leukemia and T cell‐specific gene expression.
A Serine Protease‐inhibitory Benzamidine Derivative Inhibits the Growth of Human Colon Carcinoma Cells
Authors: Nishimura Yasuhiko , Yasui Wataru , Yoshida Kazuhiro , Matsuyama Toshiya , Dohi Kiyohiko , Tahara Eiichi
Published: August 2005

The inhibitory effect of a serine protease‐inhibiting tetra‐benzamidine derivative, TAPP‐Br, on the cell growth of 8 human colon carcinoma cell lines was examined and the mechanism of the inhibition was analyzed. TAPP‐Br inhibited the cell growth of all the colon carcinoma cell lines, and this effect was irreversible. The expression of mRNAs for nuclear oncogenes such as MYC, FOS and JUN was decreased by TAPP‐Br after treatment for 3 h and the effect continued for 48 h‐ mRNA expression of epidermal growth factor receptor, transforming growth factor‐β and type IV collagenase was suppressed at 48 h after the initiation of TAPP‐Br treatment, suggesting an indirect action of TAPP‐Br. TAPP‐Br decreased protein kinase C activity in the participate fraction, whereas it increased the enzyme activity in the soluble fraction. These findings overall suggest that the serine protease inhibitor, TAPP‐Br, might inhibit the cell growth of colon carcinoma cell lines through suppressing the expression of genes whose promoter contains a 12–0‐tetradecanoylphorbol‐13‐acetate‐responsive element or serum‐responsive element.
High Sensitivity to Peripheral Blood Lymphocytes and Low HLA‐class I Antigen Expression of Small Cell Lung Cancer Cell Lines with Diverse Chemo‐radiosensitivity
Authors: Tanio Yoshiro , Watanabe Masatoshi , Osaki Tadashi , Tachibana Isao , Kawase Ichiro , Kuritani Taro , Saito Shin'ichi , Masuno Tomiya , Kodama Nagahisa , Furuse Kiyoyuki , Kishimoto Tadamitsu
Published: August 2005

Three cell lines of small cell lung cancer (SCLC), which were established from specimens of untreated primary tumors biopsied by diagnostic bronchofiberscopy, were analyzed for immunological characteristics. These cell lines showed considerable heterogeneity in chemo‐radiosensitivity, which was well correlated with clinical responses of the respective tumors, but their HLA‐class I antigen expressions were equally depressed and they were susceptible to peripheral blood lymphocytes (PBL) and lymphokine‐activated killer (LAK) cells, irrespective of their diverse chemo‐radiosensitivity. Treatment of the cell lines with recombinant immune interferon (rIFN‐γ) increased their HLA‐class I antigen expression and conversely depressed PBL sensitivity but not LAK sensitivity. This inverse relationship between HLA‐class I expression and PBL susceptibility was also demonstrated using other pairs of autologous PBL and SCLC cell lines. rIFN‐γ changed neither HLA‐class H antigen nor SCLC‐spccilic antigen expression under the same experimental conditions. In vitro immunization of allogeneic peripheral blood lymphocytes with rIFN‐γ ‐treated SCLC cells induced allo‐specific killer cells which lysed rIFN‐7‐treated more strongly than non‐treated SCLC cells. These results suggest that reduced HLA‐class I antigen expression of SCLC could protect the cancer from attack of killer T cells in spite of the higher sensitivity to PBL or LAK cells.
Alteration of Type II Regulatory Subunit of cAMP‐dependent Protein Kinase in Human Cisplatin‐resistant Cells as a Basis of Collateral Sensitivity to 8‐Chloro‐cAMP
Authors: Nishio Kazuto , Morikage Toshihiko , Kubota Naohiro , Ohmori Tohru , Takeda Yuichiro , Fujiwara Yasuhiro , Miki Keizaburo , Abe Kaoru , Saijo Nagahiro
Published: August 2005

A cyclic adenosine 3′,5′‐monophosphate (cAMP) analogue, 8‐chloro‐cAMP (8‐Cl‐cAMP), had a collateral growth‐inhibitory effect on a cis‐diamminedichloroplatinum(II) (CDDP)‐resistant human cancer cell lines (PC‐14/CDDP). The non‐selective analogues dibutyryl‐cAMP, 8‐bromo‐cAMP and forskolin, which are cAMP agonists, showed far less cytotoxicity than 8‐Cl‐cAMP in both cell lines. There was no significant difference in cAMP content between PC‐14 and PC‐14/CDDP. Because 8‐Cl‐cAMP has been shown to bind selectively to the site I receptor of the type II regulatory subunit (RII) of cAMP‐dependent protein kinase, we determined the level of expression of regulatory subunits in PC‐14 and PC‐14/CDDP cells by photoaffinity labeling. PC‐14/CDDP cells had a higher RII level, low site I receptor of type I regulatory subunit (RI) level, and a lower RI/RII ratio than the parental PC‐14 cells. Exposure to 8‐Cl‐cAMP increased the RI and RII level in PC‐14/CDDP cells in dose‐ and time‐dependent manners. On the other hand, in parental PC‐14 cells, RII was not detected and the levels of RI and RII were not increased by exposure to 8‐Cl‐cAMP. These results suggested that the change in RI and/or RII levels caused by 8‐Cl‐cAMP was correlated with 8‐Cl‐cAMP‐induced growth inhibition and that the collateral sensitivity to 8‐Cl‐cAMP in CDDP‐resistant cells was due to the increased RII level. Our results suggest that 8‐Cl‐cAMP can be used in combination with CDDP and that measurement of RI and RII levels and/or the RI/RII ratio is a useful tool to predict CDDP sensitivity.
Therapeutic Effect of Ansamitocin Targeted to Tumor by a Bispecific Monoclonal Antibody
Authors: Okamoto Kayoko , Harada Kaori , Ikeyama Shuichi , Iwasa Susumu
Published: August 2005

We have constructed a murine hybrid hybridoma that secretes a bispecific monoclonal antibody (mAb) by fusing a hybridoma secreting an anti‐ansamitocins mAb with a hybridoma secreting an anti‐human transferrin receptor (TfR) mAb that binds to human A431 epidermoid carcinoma cells. The bispecific mAb, reactive to both ansamitocins and TfR, was purified by a combination of hydrophobic column chromatography and hydroxyapatite high‐performance liquid chromatography, and evaluated in in vivo experiments using human tumor cell‐implanted nude mice. Ansamitocin P‐3 targeted through one of the antigen combining sites of the bispecific mAb was potentially more effective in suppressing the growth of established A431 tumor xenografts implanted on nude mice than unconjugated ansamitocin P‐3 or the immunoconjugate of ansamitocin P‐3 and monospecific anti‐ansamitocins antibody, and the targeted ansamitocin P‐3 finally eradicated the tumor mass. The bispecific mAb also played an important role in reducing such undesirable side‐effects of ansamitocin P‐3 as the loss of body weight, the damage to liver functions and the decrease in the number of white blood cells.
Induction of Adenocarcinomas in the Glandular Stomach of BALB/c Mice Treated with N‐Methyl‐N‐nitrosourea
Authors: Tatematsu Masae , Ogawa Kumiko , Hoshiya Toru , Shichino Yutaka , Kato Toshio , Imaida Katsumi , Ito Nobuyuki
Published: August 2005

Male 6‐week‐old BALB/c strain animals (groups 1 and 2) received 10 weekly intragastric intubations of 0.5 mg/mouse of N‐methyl‐N‐nitrosourea. At week 11 the forestomachs were resected in group 1 but not group 2. Although many animals in group 2 died due to development of squamous cell carcinomas in the forestomach, development of cancers in the glandular stomach was quite similar in both groups. Well‐differentiated adenocarcinomas in groups 1 and 2 were found at low incidence at week 20, rising to 100% at week 40, with two lesions metastasizing to the lymph nodes. Four poorly differentiated adenocarcinomas and 5 signet ring cell carcinomas were also found in 27 glandular stomach tumor‐bearing animals.
High Correlation between Lipid Peroxide Radical and Tumor‐promoter Effect: Suppression of Tumor Promotion in the Epstein‐Barr Virus/B‐Lymphocyte System and Scavenging of Alkyl Peroxide Radicals by Various Vegetable Extracts
Authors: Maeda Hiroshi , Katsuki Takato , Akaike Takaaki , Yasutake Ritsu
Published: August 2005

We examined the ability of hot‐water extracts of 66 vegetables and plants to suppress tumor promotion, as well as to scavenge lipid peroxide radicals in vitro. To assess the effect against tumor promotion (transformation) in vitro, we used the phorbol myristate acetate/Epstein‐Barr virus/ B‐lymphocyte system. To assess the lipid radical‐scavenging effect, the luminol‐enhanced cliemi‐luminescence method using the tot‐butyl hydroperoxide/heme system was used, which generates more alkyl peroxide radical (ROO·) than alkyl (R·) and alkoxyl <RO) radicals. The results showed a significant correlation between the anti‐tumor‐promoting effect and the lipid radical‐scavenging effect (r=0.82). We found that boiled extracts of green leaves of carrot, crucifers, and beans (black bean, red bean, mung bean, and soybean) had the greatest anti‐tumor‐promoter and radical‐scavenging activities. Cold‐water extracts of vegetables generally exhibited only about 10% or less of the activity of the hot‐water extracts.
Absence of ras Family Point Mutations at Codons 12, 13 and 61 in N‐Ethyl‐N‐hydroxyethylnitrosamine‐ or N‐Nitrosomorpholine‐induced Renal Cell Tumors in Rats
Authors: Matsumoto Kazuyuki , Tsuda Hiroyuki , Iwase Teruhiko , Ito Mitsuya , Nishida Yoshihisa , Oyama Fumitaka , Titani Koiti , Ushijima Toshikazu , Nagao Minako , Hirono Iwao
Published: August 2005

The prevalence of Ki‐ras, Ha‐ras and N‐ras point mutation within exons 1 and 2 was studied in 17 cases of renal cell tumors (8 carcinomas and 9 adenomas) induced by N‐ethyl‐N‐hydroxyethylnitrosamine or N‐nitrosomorpholine. DNA samples prepared from acetone‐fixed, paraffin‐embedded tissues were amplified by means of the polymerase chain reaction, and point mutations at codons 12, 13 and 61 were analyzed by direct sequence methods with oligonucleotide primers. No mutations were detected in any of the renal tumors. The results thus indicated that ras family point mutation is not necessary for kidney tumor development in rats, supporting the view that ras mutations may not be generally relevant to neoplastic development in various organs in different species.
Anti‐promoting Effect of Nordihydroguaiaretic Acid on N‐Butyl‐N‐(4‐hydroxybutyl)nitrosamine and Sodium Saccharin‐induced Rat Urinary Bladder Carcinogenesis
Authors: Yu Akinori , Hashimura Takayuki , Nishio Yasunori , Kanamaru Hiroshi , Fukuzawa Shigeki , Yoshida Osamu
Published: August 2005

The effects of oral administration of nordihydroguaiaretic acid (NDGA), an antioxidant and inhibitor of arachidonic acid metabolism, on rat bladder carcinogenesis were examined. Six‐week‐old male Fischer 344 rats were given drinking watar containing 0.05% N‐butyl‐N‐(4‐hydroxybutyl)nitrosamine for 4 weeks. Following this 4‐week period, diet containing 5% sodium saccharin (SS) with or without 0.1% NDGA supplement was given to the rats for 36 weeks. The incidences of papillary or nodular (PN) hyperplasia and of papilloma in the group treated with SS plus NDGA were significantly lower than those in the group treated with SS alone. The number of PN hyperplasic foci per 10 cm of basement membrane in rats treated with SS plus NDGA was also lower than that in the group treated with SS alone. These results suggest that NDGA has an anti‐tumor‐promoting effect on rat bladder carcinogenesis.
Synergism of Environmental Carcinogens and Promoters on Bladder Cancer Development Initiated by N‐Butyl‐N‐(4‐hydroxybutyl)nitrosamine in F344 Rats
Authors: Ono Satoko , Kurata Yasushi , Shichino Yutaka , Sano Masashi , Fukushima Shoji
Published: August 2005

Synergistic or additive effects of combined treatments with carcinogens or promoters on N‐butyl‐N‐(4‐hydroxybutyl)nitrosamine (BBN)‐initiated rat bladder carcinogenesis were examined. Male F344 rats were given BBN as an initiator followed by low doses of 3 sodium salts (sodium bicarbonate, sodium L‐ascorbate and sodium citrate) and/or 3 antioxidants (butylated hydroxyanisole, butylated hydroxytoluene and tertiary butylhydroxyquinone). Combined treatments with 3 sodium salts or 3 antioxidants, and especially all 6 chemicals together promoted bladder carcinogenesis. In addition, these combined treatments were associated with increased DNA synthesis of the bladder epithelium. Combined administration of the carcinogens, o‐anisidine, p‐cresidine, and 4‐chloro‐o‐phenylenedi‐amine at low doses also enhanced BBN‐initiated bladder carcinogenesis. These results indicate that environmental carcinogens or promoters can exert synergistic or additive actions on bladder cancer induction.
High Incidence of p53 Gene Mutation in Human Ovarian Cancer and Its Association with Nuclear Accumulation of p53 Protein and Tumor DNA Aneuploidy
Authors: Kihana Toshimasa , Tsuda Hitoshi , Teshima Shinichi , Okada Shuichi , Matsuura Shumpei , Hirohashi Setsuo
Published: August 2005

Using the poylmerase chain reaction and single‐strand conformation polymorphism analysis, p53 gene mutations were examined in 24 cases of ovarian tumor including 14 ovarian carcinomas and 2 borderline cases of common epithelial type, 7 germ cell tumors, and one stromal tumor. Abnormal bands indicating mutations were detected in 12 (50%) of the cases examined, being present most frequently in common “epithelial” ovarian carcinoma (71%, 10/14). One case each of squamous cell carcinoma originating in a dermoid cyst and anaplastic dysgerminoma were positive for mutation. Direct sequencing confirmed 12 mutations and revealed G→A and G→C nucleotide changes in 5 and 3 cases (42% and 25%), respectively. The mutation was localized at the CpG site of the gene in 3 cases. Immunohistochemical examination of p53 protein in 21 cases and DNA flow‐cytometrical analysis in 17 cases were also performed. Nuclear accumulation of the p53 protein and DNA aneuploidy pattern were detected in 11 (52%) and 9 (53%) cases, respectively. These were significantly correlated with p53 gene mutation (P<0.01 and P<0.05, respectively; Fisher's exact test). Neither mutation of the p53 gene, nuclear accumulation of p53 protein nor DNA aneuploidy was detected in borderline cases of common “epithelial” type, typical dysgerminoma and immature teratoma. These results suggest that p53 gene mutation, nuclear accumulation of the protein and the DNA aneuploidy pattern are events occurring almost simultaneously in the progression of ovarian tumors, and that p53 abnormalities seem to be correlated with a high grade of malignancy.
Maintenance of Androgen‐, Glucocorticoid‐ or Estrogen‐responsive Growth in Shionogi Carcinoma 115 Subline Sustained in Castrated Mice with High Dose of Estrogen for 30 Generations (3 Years)
Authors: Fujita Masaki Q. , Yasui Toshiyuki , Sato Bunzo , Uchida Naomi , Uchida Kiyohisa , Shiratori Osamu , Takeda Kenichi , Matsumoto Keishi
Published: August 2005

Shionogi carcinoma 115 (SC115), an androgen‐dependent mouse mammary tumor, rapidly loses its androgen responsiveness after androgen withdrawal. The growth of this tumor can also be stimulated by high doses of estrogen or glucocorticoid. In the present study, the maintenance of hormone‐responsive growth of SC115 tumors with a high dose of estrogen was examined in castrated male mice using an SCI 15 subline obtained by serial transplantations of SCI 15 tumors in estrogen‐treated castrated mice for 3 years (30 generations) (subline E2). Seed tumors from both SC115 and subline E2 could rapidly grow in castrated mice given daily injections of testosterone propionate (TP), 17β‐estradiol (E2), or dexamethasone (Dex) (100 μg/mouse/day) but not in those given vehicle alone. Although SCI 15 and subline‐E2 tumors grown with TP or Dex showed temporary regression after steroid withdrawal, the tumors grown with E2 did not show such temporary regression. The TP‐, E2‐, or Dex‐induced growth of subline‐E2 tumors was almost the same as that of the original SCI 15 tumors. However, responsiveness to androgen, estrogen or glucocorticoid of both tumors disappeared within one passage in steroid‐depleted castrated mice. The present findings demonstrate that the loss of responsiveness to androgen as well as to high doses of estrogen or glucocorticoid of SCI 15 tumors can be prevented in castrated mice not only with androgen but also with high doses of estrogen.
Potentiation of the Vincristine Effect on P388 Mouse Leukemia Cells by a Newly Synthesized Dihydropyridine Analogue, PAK‐200
Authors: Shudo Norimasa , Fujii Ryu‐ichi , Matsumoto Tamotsu , Mizoguchi Tetsuro , Seto Kiyotomo , Sakoda Ryozo , Akiyama Shin‐ichi
Published: August 2005

A newly synthesized dihydropyridine analogue, 2‐[benzyl(phenyl)amino]ethyl 1,4‐dihydrb‐2,6‐dimethyl‐5‐(5,5‐dimethyl‐2‐oxo‐l,3,2‐dioxaphosphorinan‐2‐yl)‐l‐(2‐morpholinoethyl)‐4‐(3‐nitrophen‐yl)‐3‐pyridinecarboxylate (PAK‐200), at 1 μM completely reversed the resistance to vincristine in vincristine‐resistant P388 mouse leukemia cells (P388/VCR), in vitro. PAK‐200 at 2 μM inhibited the efflux of [3H]vincristine from P388/VCR and increased the accumulation of [3H]vincristine in P388/VCR to a level similar to that in P388 cells. P‐Glycoprotein in membrane vesicles from P388/ VCR cells was photolabeled with [3H]azidopine. The labeling was completely inhibited by 10 μM PAK‐200. The calcium antagonistic activity of PAK‐200 was about 1000 times lower than that of another dihydropyridine analogue, nicardipine. Experiments with P388 and P388/VCR‐bearing mice showed that PAK‐200 enhanced the effect of vincristine on both leukemia cells in vivo. These results suggest that PAK‐200 interacts with P‐glycoprotein and reverses drug resistance in P388 mouse leukemia cells in vitro, and that PAK‐200 has an ability to potentiate the effect of vincristine on P388 mouse leukemia cells in vivo.