bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Mass Screening for Breast Cancer from the Aspect of Psychosocial Assessment of the Quality of Life
Authors: Yokoe Takao , Ishida Tsunehiro , Tominaga Suketami , Kuroishi Tetsuo , Morimoto Tadaoki , Tashiro Hideya , Itoh Sueyoshi , Abe Rikiya , Ota Jun , Horino Toshio , Taguchi Tetsuo , Honda Kazuyoshi , Sasakawa Michizou , Kashiki Yoshitomo , Yamamoto Satoru , Enomoto Kohji , Ogita Masami , Yoshida Koichi , Kido Choichiro , Fukuda Mamoru , Watanabe Hiromu , Izuo Masaru
Published: August 2005

To assess the quality of life (QOL) in patients with breast cancer receiving mass screening, a collaborative matched case‐control study was conducted in nine hospitals throughout Japan. A total of 122 patients detected by mass screening (study group) and 226 patients found in out‐patient clinics (control group) were assessed psychosocially on the basis of questionnaire information. The incidence of patients with early stage breast cancer was significantly higher in the study group than in the control group (P<0.05). Chest wall pain was observed in 35.2% of the study group and in 46.5% of the control group (P<0.05). Although control patients were more optimistic than study group patients, disturbed daily life and anxiety about recurrence were a little more frequent in the former group than in the latter. In particular, shoulder stiffness was frequently seen in the control group (P<0.05). Early detection and information do not create anxiety in mass screening patients (P<0.01). We should recommend mass screening to patients to detect early stage breast cancer and provide better QOL.
Enhancement of Cytosine Arabinoside Cytotoxicity by Granulocyte/Macrophage Colony‐stimulating Factor and Granulocyte Colony‐stimulating Factor in a Human Myeloblastic Leukemia Cell Line
Authors: Takauji Rumiko , Tohyama Kaoru , Ueda Takanori , Nakamura Toru
Published: August 2005

Enhancement of the cytotoxicity of cytosine arabinoside (ara‐C) by granulocyte/macrophage colony‐stimulating factor (GM‐CSF) and granulocyte colony‐stimulating factor (G‐CSF), and the mechanisms involved, were studied in the AML‐193 human leukemia cell line. AML‐193 cells require GM‐CSF and G‐CSF(CSFs) for optimum growth, and 24 h deprivation of CSFs decreased DNA synthesis measured in terms of 3H‐thymidine incorporation. The DNA synthesis gradually recovered upon addition of CSFs. To examine the sensitivity to ara‐C under different growth conditions, two groups of cell suspensions, one pretreated with CSFs after 24 h deprivation (CSFs(+) cells), and the other held continuously under CSFs‐free conditions (CSFs(‐) cells), were exposed to 1.0 μg/ml of ara‐C for 16 h. In clonogenic assays, CSFs(+) cells showed higher sensitivity to ara‐C than CSFs(‐) cells. These cell groups showed no significant difference in ara‐C triphosphate accumulation or retention, though the amount of ara‐C incorporated into the acid‐insoluble fraction was two times greater in CSFs(+) cells than CSFs(‐) cells, and that difference became even clearer in the retention pools. These data suggest that the enhancement of cytotoxicity by CSFs was due to the promotion of ara‐C incorporation into DNA as a result of an increase of the cell fraction in the S phase.
Pharmacokinetic Evaluation of (Glycolato‐O, O′) diammine Platinum(II) in Lung Lymph in Sheep
Authors: Koizumi Tomonobu , Kubo Keishi , Shinozaki Shirou , Koyama Shigeru , Amari Toshiya , Hayano Toshihide , Fujimoto Keisaku , Kobayashi Toshio , Sekiguchi Morie , Sakai Ryosuke , Ohshima Taeyuki , Miyamoto Ken‐ichi
Published: August 2005

The pharmacokinetics of (glycolato‐O, O′)diammine platinum(II) (254‐S), especially the distribution and behavior in the lung lymph in sheep, was investigated and compared with that of cis‐diammine‐dichloroplatinum(II) (CDDP). The blood and lung lymph fluid were collected from the carotid artery and a lung lymph fistula, respectively, in conscious sheep following intravenous infusion of 100 mg/body of 254‐S and CDDP for 30 min. The concentrations of these platinum complexes were measured by using atomic absorption spectrometry. We analyzed the data using an anatomically based model including part of the lymphatic circulation. The ultrafilterable platinum of 254‐S showed much larger area under the curve (AUC) and transfer rate constants than that of CDDP, even though the mean residence times were the same. The total platinum showed the opposite pharmacokinetic behavior. In anesthetized sheep, when lung tissue samples were obtained by biopsy at the same times as those of blood and lung lymph sampling after infusion of these drugs, 254‐S distributed in lung tissue appeared to move more easily into lung lymph than CDDP, which tended to be retained in lung tissue. These differences in pharmacokinetic behavior between 254‐S and CDDP seemed to be caused by differences in their strength of protein binding, the association constants of 254‐S for plasma and lymph protein were much less than those of CDDP. From these results, 254‐S may have favorable therapeutic effects on intrathoracic malignacies such as lung cancer and lymph metastasis
Enhancement of Reversing Effect of Cyclosporin A on Vincristine Resistance by Anti‐P‐glycoprotein Monoclonal Antibody MRK‐16
Authors: Naito Mikihiko , Tsuge Harumi , Kuroko Chie , Tomida Akihiro , Tsuruo Takashi
Published: August 2005

The synergistic effect of MRK‐16, a monoclonal antibody against P‐glycoprotein, and cyclosporin A (CsA) on the modulation of vincristine resistance was studied by isobologram analysis in three different, highly multidrug‐rcsistant tumor cells. In all cell lines, the synergistic effect was demonstrated at various concentrations of MRK‐16 and CsA. While MRK‐16 alone did not enhance the sensitivity of the moderately resistant KB‐8–5 cells to vincristine, it increased two‐fold the reversing effect of cyclosporin A at 1 μM, an achievable blood concentration. Since MRK‐16 alone showed therapeutic effects against multidrug‐resistant tumors, the combined use of MRK‐16, CsA and antitumor agents should provide therapeutic benefits for the treatment of resistant tumors.
Different Effects of Regenerative and Direct Mitogenic Stimuli on the Growth of Initiated Cells in the Resistant Hepatocyte Model
Authors: Coni Pierpaolo , Pichiri‐Coni Giuseppina , Curto Marcello , Simbula Gabriella , Giacomini Laura , Sarma Dittakavi S. R. , Ledda‐Columbano Giovanna M. , Columbano Amedeo
Published: August 2005

The possible mechanism(s) responsible for the different effects exerted by proliferative stimuli of different nature on the appearance of enzyme‐altered hepatic foci, were investigated in male Wistar rats. Rats given an initiating dose of diethylnitrosamine (150 mg/kg body weight) were fed a diet containing 0.03% acetylaminofluorene for 2 weeks. Between the first and the second week, cell proliferation was induced by a proliferative stimulus of compensatory type (partial hepatectomy) or by a direct mitogenic stimulus (lead nitrate, 100 μmol/kg). The effect of the two different proliferative stimuli on the appearance of γ‐glutamyl transferase‐positive foci was monitored by killing the rats for examination at 1, 2, 3, 5, and 6 days after the induction of cell proliferation. The results indicate that while enzyme‐altered hepatocytes can be observed as early as 3 days after partial hepatectomy and are characterized by a rapid growth, direct hyperplasia did not exert any effect on the growth capacity of initiated cells. No effect of lead nitrate‐induced hyperplasia was observed following three administrations of the mitogen. When platelet‐poor plasma taken from animals exposed to the different proliferative stimuli was tested in primary cultures of hepatocytes, it was found that it induced a significant increase in the labeling index of normal hepatocytes. However, while serum taken 6 days after partial hepatectomy was still able to induce a significant increase in the labeling index, platelet‐poor plasma from lead‐treated rats had lost part of its effect at 5 days after treatment. The inability of direct hyperplasia to stimulate the development of enzyme‐altered hepatic foci was not unique to lead nitrate since the same phenomenon was observed when three other hepatomitogens, nafenopin, cyproterone acetate, and ethylene dibromide, were used.
Elevated Level of 8‐Hydroxydeoxyguanosine in DNA of Liver, Kidneys, and Brain of Long‐Evans Cinnamon Rats
Authors: Yamamoto Fuyumi , Kasai Hiroshi , Togashi Yuji , Takeichi Noritoshi , Hori Tomokatsu , Nishimura Susumu
Published: August 2005

Long‐Evans Cinnamon (LEG) rats, a mutant strain originating from Long‐Evans rats, spontaneously develop hereditary hepatitis followed by hepatocellular carcinoma. The hepatic disorder in LEC rats is associated with their abnormal copper metabolism; metal‐catalyzed reactions often give rise to oxygen radicals, which may be related to the carcinogenesis. By means of high‐pressure liquid chromatography with electrochemical detection, cellular DNA damage caused by oxygen radicals can be assessed in terms of the amount of 8‐hydroxydeoxyguanosine (oh8dG). We assayed the amount of oh8dG in DNA of liver, kidneys, and brain of LEC and Long‐Evans Agouti (LEA) control rats in seven groups (n=3 to 6) aged from 5 weeks to 24 months. Control rats, a healthy sibling line, were age‐matched. The amount of oh8dG was correlated with the severity of the age‐related clinical symptoms in LEC rats. The amount was higher in LEC rats than in the controls, especially in the liver at the acute stage of hepatitis. These findings suggest that oxygen radicals may be important in the carcinogenesis that occurs in LEC rats.
N‐Nitroso‐N‐ethylurea‐induced Hamster Melanoma: A New Method for Efficient Induction and Schwannian Differentiation of Melanoma
Authors: Nemoto Tetsuo , Nakamura Takuro , Ohashi Kenichi , Kasuga Tsutomu
Published: August 2005

Melanocytic tumors as well as multiple neurofibromas were induced in 35 of 88 Syrian golden hamsters by a single s.c. administration of 100 mg/kg of N‐nitroso‐N‐ethylurea applied 48 h after birth. The lesions were all observed proliferating in the dermis and demonstrated melanosomes and premelanosomes. High cellularity, nuclear atypia and transplantability of the tumors in outbred hamsters suggested a malignant nature. Some of the melanomas were morphologically heterogenous and contained Schwann‐like cells as minor components. In addition, transplantation of the melanomas resulted in increased schwannian differentiation even for primary tumors which did not contain any Schwann‐like cell foci. One of the transplanted melanomas mimicked malignant peripheral nervous tumor. Schwannian differentiation was also proved by the fact that glial fibrillary acidic protein was positive in 22.2% of the cases. The present results suggest that the induced hamster melanomas originate from neural crest‐derived cells which are able to differentiate into both melanocytes and Schwann cells.
Genetic Alterations in Thyroid Tumor Progression: Association with p53 Gene Mutations
Authors: Ito Takashi , Seyama Toshio , Mizuno Terumi , Tsuyama Naohiro , Hayashi Yuzo , Dohi Kiyohiko , Nakamura Nori , Akiyama Mitoshi
Published: August 2005

To identify the genetic events that must be involved in thyroid tumor progression, we initially investigated p53 gene alterations in 10 papillary adenocarcinomas, 4 follicular adenocarcinomas, and 8 undifferentiated carcinomas. Base substitutional mutations in exons 5 to 8 and loss of heterozygosity (LOH) of the p53 gene were not detected in papillary or follicular adenocarcinomas. However, 7 of 8 undifferentiated carcinomas were carrying base substitutional mutations, and LOH was detected in 3 of 5 informative cases. Furthermore, to verify that the p53 gene alterations are truly involved in tumor progression, DNA from individual foci of the four undifferentiated carcinomas coexisting with a differentiated focus and from one follicular adenocarcinoma with an undifferentiated focus was analyzed by direct sequencing and polymerase‐chain‐reaction‐restriction‐fragment‐length polymorphism (PCR‐RFLP). Base substitutional mutations in the p53 gene from exons 5 to 8 were identified exclusively in the undifferentiated foci, but not in the differentiated foci. LOH was observed in 3 of 4 informative undifferentiated foci. In one of these positive cases, LOH was observed in both papillary adenocarcinoma and undifferentiated carcinoma. However, a p53 gene mutation at codon 248 was detected in the undifferentiated carcinoma but not in the papillary adenocarcinoma. The results imply that LOH occurs first in papillary adenocarcinoma followed by a p53 mutation during the transition from papillary adenocarcinoma to undifferentiated carcinoma. Maintenance of LOH during tumor progression excludes the possibility that these different histological foci are derived from different origins and represents molecular evidence that undifferentiated carcinoma is very likely derived from preexisting papillary adenocarcinoma. Furthermore, these results strongly suggest that the mutated p53 gene plays a crucial role in de‐differentiation during the progression of thyroid tumors.
Molecular Cloning of 19p13 Breakpoint Region in Infantile Leukemia with t(11;19)(q23;p13) Translocation
Authors: Iida Shinsuke , Seto Masao , Yamamoto Kazuhito , Komatsu Hirokazu , Akao Yukihiro , Nakazawa Shinpei , Ariyoshi Yutaka , Takahashi Toshitada , Ueda Ryuzo
Published: August 2005

We studied the breakpoint regions involved in t(11;19)(q23;p13) translocation associated with infantile leukemias. Southern blot analysis with the partial cDNA clone for the MLL gene at 11q23 which we had isolated previously detected gene rearrangements in all three cell lines and three leukemia samples from the patients with t(11;19) translocation, indicating that these breakpoints were clustered within the 8.5 kb BamHI germline fragment detected by the probe. To study the breakpoint region, a genomic library of one of the cell lines, KOCL‐33, was made. We have isolated the der(19) allele containing the breakpoint as well as the germline alleles at 19p13 and 11q23. Using the genomic probes on chromosome 19 near the breakpoint, Southern blot analysis was performed. The breakpoints at 19p13 of the two other cell lines and the three leukemia samples were not located within 36 kilobases of the KOCL‐33 breakpoint, although pulsed‐field gel electrophoresis showed that the breakpoints of all three cell lines were on the same NruI fragment of 230 kilobases. These results showed that the breakpoints at 19p13 were not clustered like those at 11q23 in t(11;19) translocation.
Detection of Active Form of Transforming Growth Factor‐β in Cerebrospinal Fluid of Patients with Glioma
Authors: Tada Tsuyoshi , Yabu Kouji , Kobayashi Shigeaki
Published: August 2005

We examined transforming growth factor‐β (TGF‐β) activity in cerebrospinal fluid of 39 patients with various brain tumors, and found it in 10 glioma cases that had lesions related to subarachnoid space or ventricle. In one glioma case, TGF‐β detected on admission disappeared after radiation and chemotherapy. We confirmed that five glioma cell lines produced TGF‐β, and that four of them produced active form of TGF‐β directly. The active form of TGF‐β was also identified from cerebrospinal fluid before the acidification treatment in two cases. The calculated contents were 110 ng/ml and 18 ng/ml. These results indicate that active form of TGF‐β is directly produced by tumor cells in patients with glioma, and may contribute to immunodeficiency of the host.
Augmented Expression of a Type IV Collagen‐binding Protein in a Highly Metastatic Murine Fibrosarcoma Clone
Authors: Kogawa Katsuhisa , Mogi Yoshihiro , Takayama Tetsuji , Koike Kazuhiko , Yoshizaki Naohito , Muramatsu Hiroshi , Niitsu Yoshiro
Published: August 2005

The adhesive properties of highly and weakly metastatic murine sarcoma (Meth A) clones were investigated. A highly metastatic clone, MH‐02, preferentially adhered to type IV collagen‐coated plastic dishes and to bovine pulmonary arterial endothelial cell‐coated plastic dishes as compared to a weakly metastatic clone, ML‐01. Pretreatment of MH‐02 and ML‐01 cells with antisera against MH‐02 cells resulted in almost equivalent adhesiveness to type IV collagen. Preincubation of 125I‐radiolabeled tumor cells with the antisera against MH‐02 significantly reduced the arrest of MH‐02 cells in the lung, but ML‐01 cells were not affected. The number of pulmonary metastatic nodules of MH‐02 cells was reduced to the same level as that of ML‐01 cells by preincubation of the tumor cells with the antisera in an experimental metastasis experiment. These results indicated that the high metastatic ability of MH‐02 can be attributed to its preferential adhesiveness to type IV collagen. The type IV collagen‐binding proteins of MH‐02 and ML‐01 were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) and autoradiography. Among several proteins which bound to type IV collagen, expression of a protein with a molecular weight of 29 kD was significantly greater in MH‐02 than in ML‐01. These results suggest that the greater adhesion of highly metastatic MH‐02 cells to type IV collagen is due to enhanced expression of the type IV collagen‐binding 29 kD protein.
ED‐110, a Novel Indolocarbazole, Prevents the Growth of Experimental Tumors in Mice
Authors: Arakawa Hiroharu , Iguchi Tomoko , Yoshinari Tomoko , Kojiri Katsuhisa , Suda Hiroyuki , Okura Akira
Published: August 2005

A new indolocarbazole compound, ED‐110, which was obtained by glucosylating a microbial product (BE‐13793C) and is a potent topoisomerase I inhibitor, showed characteristic inhibitory effects on the growth of 12 human tumor cell lines tested. The IC50 values of ED‐110 against 9 of the 12 lines ranged from 11.5 μg/ml to 0.07 μg/ml, while the remaining 3 lines were quite resistant (IC50, >100μg/ml). In in vivo experiments, i.p. treatment with ED‐110 increased the survival period by more than two‐fold in mice implanted i.p. with P388, L1210, L5178Y or EL4 murine leukemic cells. The minimum effective dose increasing the life‐span of mice bearing P388 leukemia by 25% was <2.5 mg/kg/day × 10 and the maximum tolerated dose was > 160 mg/kg/day × 10. ED‐110 was also effective against the spontaneous metastasis of mouse Meth A fibrosarcoma cells and the growth of xenografted MKN‐ 45 human stomach cancer cells as well as s.c. implanted mouse colon 26 and IMC carcinoma cells. These results indicated that ED‐110 may have potential as a new antineoplastic agent with a large chemotherapeutic index and a wide range of effective doses.
Enhancement of Ultrasonically Induced Cell Damage by a Gallium‐Porphyrin Complex, ATX‐70
Authors: Umemura Shin‐ichiro , Yumita Nagahiko , Nishigaki Ryuichiro
Published: August 2005

Enhancement of ultrasonically induced cell damage by a gallium‐porphyrin complex [ATX‐70, 2,4‐ bis(l‐decyloxyethyl)‐Ga(III)‐1,3,5,8‐tetramethylporphyrin‐6,7‐dipropionyl diaspartic acid] was investigated. The rate of damage to isolated sarcoma 180 cells in air‐saturated suspension induced by 2 MHz ultrasound irradiation was enhanced more than four times by 80 μM ATX‐70 in contrast to only twice by the same concentration of hematoporphyrin (Hp). The enhancement was almost completely inhibited in the presence of 10 mM histidine in the suspension, but not at all by 100 mM mannitol, which suggests that the enhanced cell damage was mostly mediated by singlet oxygen. Ultrasonically induced active oxygen generation in an air‐saturated aqueous solution of ATX‐70 was studied by detecting the electron spin resonance signals of 2,2,6,6,‐tetramethyl‐4‐piperidone‐N‐oxyl produced by the reaction of 2,2,6,6‐tetramethyl‐4‐piperidone with the generated active oxygen species. The rate of ultrasonically induced nitroxide generation was enhanced five times by 80 μM ATX‐70 in contrast to only twice by Hp. The enhancement was inhibited significantly in the presence of 10 mM histidine in the suspension, but not at all by 100 mM mannitol. The singlet oxygen generation in air‐saturated aqueous solution was further confirmed by the bleaching of N, N‐dimethyl‐4‐nitrosoaniline in the presence of imidazole. The ultrasonically induced bleaching rate was enhanced six times by ATX‐70, in contrast to only twice by Hp.
Detailed Characterization of a High‐molecular‐weight Glycoprotein Secreted by Lung Cancer Cells
Authors: Nonaka Noritaka , Manaka Ken‐ichi , Kobayashi Kunihiko , Hirai(deceased) Hidematsu
Published: August 2005

A cancer‐associated, high‐molecular‐weight glycoprotein antigen (6B3·Ag) recognized by monoclonal antibody 6B3 was purified from culture medium of human large cell lung carcinoma cell line (HLC‐2) and characterized biochemically and immunochemically. The 6B3·Ag was purified more than 1,200‐fold with a yield of 30% by salting out, precipitation by acidification at pH 4.5, and chromatographies on Sepharose 4B and concanavalin A‐Sepharose. The molecular weight of 6B3·Ag is approximately 1,000,000 and the molecule is a homodecamer of 94,000 subnnits. The 6B3·Ag is a glycoprotein containing 22.9% sugars, consisting of both N‐ and O‐glycoside chains. The N‐terminal 19 amino acids were determined and only 4 out of 19 amino acid residues were different from those of an antigen, L3, secreted by lung carcinoma cell line Calu‐1. The serum level of 6B3·Ag was determined in normal adults as well as patients with various diseases by enzyme‐linked immunosorbent assay. The mean serum level of 6B3‐Ag was 3.1 μg/ml, ranging from 1.6 to 6.2 μg/ml in 131 healthy adults. When the cut‐off value was set at 6.2 μg/ml, the incidence of positive values in the sera was elevated not only in malignant diseases such as hepatoma (73%) and leukemia (62%), but also in benign diseases such as chronic hepatitis (42%) and liver cirrhosis (63%). While the incidence of positive values was elevated in advanced liver diseases, namely, chronic hepatitis, liver cirrhosis and hepatoma, the cancer specificity of 6B3·Ag did not appear to be high.
Protective Effects of Raw Vegetables and Fruit against Lung Cancer among Smokers and Ex‐smokers: A Case‐Control Study in the Tokai Area of Japan
Authors: Gao Chang‐ming , Tajima Kazuo , Kuroishi Tetsuo , Hirose Kaoru , Inoue Manami
Published: August 2005

In a hospital‐based case control study, the protecting effects of fruit, raw and green vegetables against lung cancer risk among male smokers were studied in 282 cases and the same number of controls. The current smokers showed a 6.61‐fold increased risk of lung cancer. The odds ratio (OR) declined markedly with starting age of smoking habit and increased markedly with number of cigarettes smoked per day. The ex‐smokers showed a 3.56‐fold increased risk of lung cancer. The ORs gradually decreased with years passed since cessation of smoking. In the single factor analysis, significant protective effects of fruit, raw vegetables, green vegetables, lettuce and cabbage against lung cancer were found. The risk for all lung cancer decreased to 0.45 (95% confidence intervals (CI) 0.30–0.67), 0.64 (95%CI 0.43–0.97) and 0.44 (95%CI 0.26–0.73) with increment of Intake frequency of fruit, raw and green vegetables respectively. The OR for lung cancer decreased to 0.41 (95%CI 0.24–0.72) and 0.56 (95%CI 0.32–0.99) with increasing intake frequency of fruit and raw vegetables among current smoking males. Lettuce and cabbage showed protective effects against lung cancer, and the OR for risk of lung cancer decreased to one‐half among the high intake frequency group. The risk of lung cancer among current smokers declined markedly with increasing intake of lettuce and cabbage. A similar effect was observed among ex‐smokers and non‐smokers, but there was no statistical significance. In the multivariate analysis, fruit and raw vegetables showed the strongest protective effects against lung cancer among current smokers (P=0.01). Among ex‐smokers, the protective effect of fruit is also statistically significant (P=0.03). These results suggest that fruit and raw vegetables may play an important role in protecting smokers from lung cancer.
Lung Cancer Incidence Rate for Male Ex‐smokers According to Age at Cessation of Smoking
Authors: Sobue Tomotaka , Yamaguchi Naohito , Suzuki Takaichiro , Fujimoto Isaburo , Matsuda Minoru , Doi Osamu , Mori Takashi , Furuse Kiyoyuki , Fukuoka Masahiro , Yasumitsu Tsutomu , Kuwahara Osamu , Ichitani Michio , Taki Toshihiko , Kuwabara Masayoshi , Nakahara Kazuya , Endo Shozo , Sawamura Kenji , Kurata Masahiko , Hattori Shoji
Published: August 2005

Lung cancer incidence rate after the cessation of smoking was assessed for male ex‐smokers according to the age at cessation, using the results from a case‐control study for ex‐smoker versus continuing smoker, and the lung cancer incidence rate function for continuing smoker estimated from Japan Vital Statistics and the “Six‐prefectural Cohort Study” in Japan. This hospital‐based case‐control study consisted of 776 lung cancer cases (553 current smokers and 223 ex‐smokers) and 772 controls (490 current smokers and 282 ex‐smokers) who started smoking at ages 18–22. The odds ratio of developing lung cancer for ex‐smokers compared to continuing smokers according to years since the cessation of smoking was estimated for four age groups (55–64, 60–69, 65–74 and 70–79). Given that the number of years since cessation of smoking is the same, reduction of the odds ratio appeared to be greater for the younger age group than for the older age group, reflecting the shorter period of exposure for the younger age group. Lung cancer incidence rate (per 100,000) was assumed to be expressed by the following function; 1.7 × 10−5× (age – 24.3)4,5 for continuing smokers and 0.15 × 10−5× (age)4 for nonsmokers. Lung cancer incidence rate among ex‐smokers according to years since cessation was then estimated to be the above function multiplied by the odds ratio from the case‐control study for each age group. In contrast to the greater reduction of the odds ratio among younger ex‐smokers, reduction of the incidence rate, in terms of rate difference, was considerably greater for older ex‐smokers due to a high incidence rate of lung cancer for older continuing smokers. This indicates that the absolute magnitude of reduction of the lung cancer incidence rate after cessation of smoking is greater for older ex‐smokers, although the relative magnitude of reduction is greater for younger ex‐smokers.
Increased Cell‐surface Urokinase in Advanced Ovarian Cancer
Authors: Kobayashi Hiroshi , Moniwa Nobuhiko , Sugimura Motoi , Shinohara Hiromitsu , Ohi Hidekazu , Terao Toshihiko
Published: August 2005

Urokinase‐type plasminogen activator (uPA), uPA receptors, and cathepsin B were quantitatcd by using an immunological method, enzyme‐linked immunosorbent assay, and amidolytic activity assays in 15 malignant and 10 benign epithelial ovarian tumors. The levels of uPA and uPA receptors, as well as cathepsin B, were found to be higher in membrane preparations obtained from malignant tumors than in those obtained from benign tumors. Acid‐treated membranes acquired the ability to bind uPA, indicating that uPA is bound to a specific surface receptor that is not completely saturated. Levels of single‐chain uPA (pro‐uPA) and high‐molecular‐weight uPA in membrane preparations were measured by immunoadsorbent‐amidolytic assay. The finding of a significant increase in amidolytic activity following activation of uPAs by plasmin suggested that less than half (30–40%) of all membrane immunoreactive uPAs is present in the enzymatically inactive pro‐uPA form. In the membranes of malignant tumors, levels of uPA receptor and cathepsin B did not vary with stage of disease. On the other hand, we found that the level of receptor‐bound uPA antigen/activity was significantly increased in advanced malignant tumors. Receptor‐bound uPA may play an important role in determining invasive potential of tumor cells. Since ovarian cancer cells produce both pro‐uPA and cathepsin B, the possibility of activation of tumor cell‐derived pro‐uPA by cellular protease cathepsin B must be considered.
Development and Characterization of a Novel Anti‐fucosylated Antigen Monoclonal Antibody YB‐2 and Its Usefulness in the Immunohistochemical Diagnosis of Colorectal Cancer
Authors: Yazawa Shin , Akamatsu Suguru , Tachikawa Tetsuya , Naito Hiroshi , Nakamura Jun‐ichi , Asao Takayuki , Nagamachi Yukio , Nakajima Takashi , Shin Sadahito , Chia David
Published: August 2005

A novel monoclonal antibody, YB‐2 was obtained after immunization of mice with fucosylated antigens isolated from human saliva. The antibody was demonstrated to react with Y (Fucα1→2Gal‐ β1→4[Fucα1→3]GlcNAcβ),Leb(Fucα1→2Galβ1→3[Fucα→4]GlcNAcβ)andHtype2 (Fucα→2Gal‐βl→4GlcNAcβ) antigens, but not with H type 1 (Fucα→2Galβ1→3GlcNAcβ), Le→ (Galβ1→3[Fucα1→4]GlcNAcβ), X (Galβ1→4[Fucα1→3]GlcNAcβ) or with non‐fucosylated antigens. Inhibition assays of YB‐2 antibody with such reactive antigens showed that YB‐2 antibody preferentially reacted with Y antigen. Formalin‐fixed and paraffin‐embedded sections prepared from normal and malignant colorectal tissues were examined immunohistochemically with YB‐2. The positive rates of staining with YB‐2 antibody were 88.6% in malignant and 12.0% in normal tissues. The expression of fucosylated antigens detected by YB‐2 antibody seemed to be correlated with survival among patients with primary colorectal cancer. Therefore, YB‐2 antibody could be useful as an immunochemical tool for diagnosis and evaluation of the prognosis of colorectal cancer.
Human Cervical Epidermal Carcinoma‐associated Intracellular Localization of Glycosphingolipid with Blood Group A Type 3 Chain
Authors: Cui Yongxi , Noguchi Hiroshi , Kiguchi Kazushige , Aoki Daisuke , Susumu Nobuyuki , Nozawa Shirou , Kawakami Hayato , Hirano Hiroshi , Iwamori Masao
Published: August 2005

A monoclonal antibody, MRG‐1, was produced by immunizing a mouse with a human ovarian mucinous cyst adenocarcinoma‐derived cell line, RMUG‐L. By immunohistochemical staining, the antigen was found to be exclusively localized in the intracellular structures of the cells used as the antigen and of the epithelial cells in normal human cervical glands. However, although the antigen was predominantly detected in the plasma membrane and the intercellular structure of the middle layer of normal human cervical squamous epithelium (92%), it was also contained in the intracellular structure of cervical epidermal carcinoma at a high frequency (80%). The striking difference in the distribution of the MRG‐1 antigen between normal and cancerous tissues was found to be a cervical carcinoma‐associated phenomenon and a useful tumor marker for immunohistochemical examination. Since the antigen was found to be of a blood group A‐related nature by immunohistochemical staining of the tissues and to be a glycosphingolipid, it was purified from human erythrocytes of blood group A, and the structure was concluded to be GalNAcα1–3Gal(2–1αFuc)jβ1–3GalNAcα1–3Gal(2–1αFuc)‐ β1–4GlcNAcβ1–3Galβl‐4Glcβ1–1′Cer, blood group A type 3 chain‐containing glycosphingolipid, by NMR, negative ion FABMS and permethylation analysis. In the subcellular localization analysis of the antigen, type 3‐A glycosphingolipid antigen was detected in the Golgi body and the microsomes of RMUG‐L cells, and the distribution coincided with the finding by immunohistochemical staining. In addition, in cervical epidermal carcinoma, although the blood group A, mainly type 2‐A chain, was localized in the plasma membrane and the intercellular structure, the blood group A type 3 chain was selectively found in the perinuclear structure. Also, the blood group A type 3 chain in cervical dysplasia as well as that in normal cervix was predominant in the plasma membrane. Thus, the selective intracellular localization of blood group A type 3 chain was a phenomenon characteristic of cervical epidermal carcinoma and the carcinoma in situ.
Interferon‐γ‐producing Tumor Induces Host Tumor‐specific T Cell Responses
Authors: Teramura Yasufumi , Watanabe Yoshihiko , Kan Norimichi , Masuda Tohru , Kuribayashi Kagemasa
Published: August 2005

We investigated the mechanism of host immune responses against two interferon‐γ (IFN‐γ) gene‐transduced tumors, plasmacytoma MOPC104E(Muγ) and mammary cancer SC115(Kγ), which originally had weak immunogenicity. Both IFN‐γ‐producing tumor cells had reduced tumorigenicity and were rejected by syngeneic mice. The rejection was completely blocked by in vivo treatment with anti‐CD8 or anti‐IFN‐γ monoclonal antibodies. While anti‐CD4 monoclonal antibody also blocked the rejection of SC115(Kγ), it enhanced the initial tumor growth of MOPC104E(Muγ). Specific protection against subsequent challenge with the respective parental tumor cells was demonstrated in mice which rejected the IFN‐γ‐producing tumor cells. Cultured lymphocytes derived from immunized mouse spleens had cytotoxic T cell activity against parental tumor cells, as well as against cells that produced IFN‐γ, These findings indicate that the antitumor effects are mediated by cytotoxic T cells and, partly, by helper T cells, and that locally secreted IFN‐γ plays an important role in generating these effector cells.
HTLV‐1‐associated Myelopathy/Tropical Spastic Paraparesis‐like Rats by Intravenous Injection of HTLV‐1‐producing Rabbit or Human T‐Cell Line into Adult WKA Rats
Authors: Kushida Shigeki , Matsumura Masayuki , Tanaka Hiroko , Ami Yoshihiro , Hori Mitsuo , Kobayashi Mikirou , Uchida Kazuhiko , Yagami Ken‐ichi , Kameyama Tsuneo , Yoshizawa Toshihiro , Mizusawa Hidehiro , Iwasaki Yuzo , Miwa Masanao
Published: August 2005

We intravenously injected Ra‐1 cells or MT‐2 cells into female adult WKA rats. Spastic paraparesis mainly in the hind‐limbs was observed in 1 out of 2 Ra‐1 cell‐injected WKA rats and in 3 out of 8 MT‐2 cell‐injected WKA rats 20 27 months after injection. The main neuropathological finding was symmetrical white matter degeneration with mononuclear cell infiltration of the spinal cord, similar to that of HTLV‐1‐associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients, and degeneration of nerve roots and peripheral nerves. Antibodies against HTLV‐1 antigens were detected in plasma and cerebrospinal fluid from these HAM/TSP‐like rats. HTLV‐1 provirus was detected from the peripheral blood mononuclear cells of one of these rats 20 months after injection. Interestingly, spastic paraparesis was not observed in F344 rats.
Inhibitory Effects of Benzyl Isothiocyanate and Benzyl Thiocyanate on Diethylnitrosamine‐induced Hepatocarcinogenesis in Rats
Authors: Sugie Shigeyuki , Okumura Ataru , Tanaka Takuji , Mori Hideki
Published: August 2005

The effects of two aromatic thiocyanates, benzyl isothiocyanate (BITC) and benzyl thiocyanate (BTC), on diethylnitrosamine (DEN)‐induced hepatocarcinogenesis were examined in rats. A total of 108 male ACI/N rats, 5 weeks old, were divided into 6 groups (18 rats in each). Group 1 was given a single i.p, injection of DEN (200 mg/kg body weight) one week after the start of the experiment and then kept on the basal diet until the end of the experiment (1 year). Groups 2 and 3 were treated with DEN and received dietary BITC (100 ppm) or BTC (100 ppm), respectively, throughout the experimental duration. Groups 4 and 5 were not given the carcinogen and were fed the diet containing BITC or BTC, respectively. Group 6 was kept on the basal diet alone and served as a control. Liver neoplasms were seen in Groups 1, 2 and 3. Incidence and average number of liver neoplasms in Group 2 were significantly smaller than in Group 1 (P<0.0005 and P<0.001, respectively). The incidence of liver neoplasms in Group 3 was slightly lower than in Group 1, although the difference was not statistically significant. The numbers of glutathione S‐transferase placental form (GST‐P)‐positive foci in Group 2 and γ‐glutarnyltranspepridase (GGT)‐positive foci in Groups 2 and 3 were significantly smaller than those in Group 1 (P<0.001). The average and unit areas of GST‐P‐ or GGT‐positive foci in Group 2 or 3 were also significantly smaller than those in Group 1 (P<0.05). These results suggest that BITC and BTC are chemopreventive agents for DEN‐induced liver tumorigenesis.
Analysis of Oncogenes and Tumor Suppressor Genes in Human Breast Cancer
Authors: Yamashita Hiroko , Kobayashi Shunzo , Iwase Hirotaka , Itoh Yukashi , Kuzushima Tatsuya , Iwata Hiroji , Itoh Kazuko , Naito Akihiro , Yamashita Toshinari , Masaoka Akira , Kimura Narimichi
Published: August 2005

Oncogenes (c‐erbB‐2, c‐myc, and some genes linked to the 11q13 lesion), tumor suppressor genes (retinoblastoma gene, p53) and an antimetastatic gene (nm23/nucleoside diphosphate kinase) play important roles in breast cancer progression. Amplification of c‐erbB‐2, c‐myc, andint‐2, and expression of RB, p53 (mutant), and NDP kinase were determined in 77 primary breast cancer specimens.nm23‐H1 allelic loss was also studied. c‐erbB‐2 and c‐mycamplification, loss of RB expression, p53(mutant) expression, andnm23‐H1 allelic loss were also found in non‐invasive carcinoma,int‐2 amplification was significantly correlated with lymph node status (P=0.02) and a significant association was found between p53(mutant) expression and tumor size (P=0.04). c‐erbB‐2 amplification was strongly associated with disease‐free and overall survival in multivariate analysis (P=0.002). All of the c‐erbB‐2 amplified cases and all but one of theint‐2 amplified cases in node‐positive patients had relapsed within 2 years post resection. The cancer cells may acquire new proliferative pathways sequentially as a result of multiple genetic alterations which enable them to bypass the estrogendependent proliferation.
Brefeldin A Blocks the Cytotoxicity of T Cell Receptor α/β and γ/δ Cytotoxic T Lymphocyte Clones Reacting against Human Autologous Cancer Cells
Authors: Wada Yoshimasa , Ikeda Hideyuki , Ueda Daisuke , Ohta Masahiko , Takahashi Shuji , Hirata Koichi , Sato Noriyuki , Kikuchi Kokichi
Published: August 2005

We studied the effector mechanism of T cell receptor (TCR) α/β‐ and γ/δ‐type cytotoxic T lymphocyte (CTL) clones that react with human autologous tumor cells. Treatment of tumor cells with a fungal antibacterial reagent, brefeldin A (BFA), resulted in the inhibition of cytotoxicity of an autologous tumor (HST‐2)‐specific CD8+ TCRα/β‐type CTL, TcHST‐2. Other anti‐metabolites such as chloroquine, cycloheximide and colchicine did not affect the cytotoxicity. The cell‐surface antigen expression, including MHC class I molecules, was not influenced by BFA treatment. Furthermore, BFA did not influence the cytotoxicity of lymphokine‐activated killer cells and natural killer cells. Since BFA blocks the transport of peptides from endoplasmic reticulum to the Golgi apparatus, the above data suggest that BFA could affect washing out of the peptide fragments from the MHC class I groove. Consequently, target tumor cells were protected from killing by CTL, Moreover, we obtained a CD4−, 8−, TCR γ/δ‐type (Vδ1+) CTL clone, TcHOT, that reacts against an autologous ovarial carcinoma, HOT. BFA could also inhibit this cytotoxicity, and it is likely that different presenting molecules other than MHC class I proteins participate in the cytotoxicity of this TCR gm/δ‐ type CTL. These studies suggest that both TCR α/β‐ and γ/δ‐type CTL may require antigenic peptides that are most likely derived from the BFA‐sensitive, intracellular endogenous target proteins.
Enhanced Tumor Localization of Radiolabeled Fab Fragments of Monoclonal Antibody A7 in Nude Mice Bearing Human Pancreatic Carcinoma Xenografts
Authors: Otsuji Eigo , Yamaguchi Toshiharu , Yamaoka Nobuki , Kato Makoto , Kotani Tatsuya , Kitamura Kazuya , Yamaguchi Nozomi , Takahashi Toshio
Published: August 2005

Much recent research has been directed toward the use of monoclonal antibodies (MAb) for the inimunodetection of solid tumors. In pancreatic cancer, the results of conventional immunoscintigraphy using intact MAb remain disappointing. Clear immunoseintigrapliy with radiolabeled MAb requires a high tumor tissue/blood ratio of radioactivity and a low normal tissue/blood ratio of radioactivity. In this study, 125I‐labeled Fab fragments produced by papain digestion of MAb A7 were injected intravenously into nude mice bearing a human pancreatic cancer (HPC‐YS) xenograft previously shown to react specifically with MAb A7. The radioactivity of tumors and normal organs was subsequently measured. The tumor tissue/blood ratio of 125I‐labeled Fab fragments of MAb A7 was 1.00±0.24 and 9.68±2.54 at 2 and 24 h after injection, respectively. The tumor tissue/blood ratio of radioactivity was significantly higher than those of normal organs at 24 h after injection. Moreover, the tumor tissue/blood ratio of 125I‐labeled Fab fragments of MAb A7 was greater than that of intact MAb A7, although the 125I‐labeled Fab accumulation level was much less than that of 125I‐labeled intact MAb A7 in the tumor. When mice bearing tumors which did not react with MAb A7 were studied, 125I‐labeled Fab fragments did not specifically localize to the tumors. These results suggest that Fab fragments of MAb A7 may be suitable carriers of radionuclides for the immunodetection of human pancreatic cancer.
Enhanced Antitumor Effect of Recombinant Human Tumor Necrosis Factor in Combination with Recombinant Human Granulocyte Colony‐stimulating Factor in BALB/c Mice
Authors: Maeda Masahiro , Watanabe Naoki , Tsuji Naoki , Tsuji Yasushi , Okamoto Tetsuro , Sasaki Hiroyoshi , Akiyama Shinichiro , Niitsu Yoshiro
Published: August 2005

The synergistic antitumor effect of tumor necrosis factor (TNF) and granulocyte colony‐stimulating factor (G‐CSF) was investigated. G‐CSF was administered subcutaneously to BALB/c mice inoculated with Meth‐A cells at a dose of 2.5 μg/day for 5 consecutive days. When TNF (1 × 103 U) was administered intravenously to mice which had been pretreated with G‐CSF, tumor growth showed a 74.1% inhibition 17 days after the tumor cell inoculation, compared to that of untreated mice. In this experiment, G‐CSF significantly (P<0.025) enhanced the antitumor effect of TNF. The in vitro cytotoxicity of TNF (10 U/ml) towards Meth‐A cells was increased about 5.2‐fold in the presence of neutrophils (E/T=50) as compared to the cytotoxicity obtained with TNF alone. A combination of TNF and G‐CSF (50 ng/ml) in the presence of neutrophils, resulted in a 2.1 times greater cytotoxicity against Meth‐A cells as compared to that obtained without G‐CSF. Significant augmenting effects of G‐CSF on superoxide (O2−) production by TNF‐stimulated neutrophils were observed. These observation suggest that the neutrophil plays an important role in the antitumor action of TNF on Meth‐A cells, and that the antitumor effect of TNF is enhanced by combination with G‐CSF.
Aberrant Expression of the p53 Tumor Suppressor Gene in Adult T‐Cell Leukemia and HTLV‐I‐infected Cells
Authors: Yamato Kenji , Oka Takashi , Hiroi Makoto , Iwahara Yoshihito , Sugito Sawa , Tsuchida Nobuo , Miyoshi Isao
Published: August 2005

By immunoprecipitation analysis, enhanced p53 expression was detected in 3 of 4 adult T‐cell leukemia (ATL) cell lines, 1 of 3 HTLV‐I‐infected cell lines and 1 of 5 fresh ATL samples, compared with phytohemagglutinin‐stimulated peripheral blood lymphocytes. Among these 5 high expressers, p53 missense mutations were indicated in 2 ATL cell lines and 1 fresh ATL sample by extensive p53 cDNA and genomic DNA polymerase chain reaction single‐strand conformation polymorphism analysis. No mutation was found throughout the entire coding region of the remaining 2 high expressers (1 ATL and 1 HTLV‐I‐infected cell lines) and low expressers of p53 (2 HTLV‐I‐infected cell lines). Tax oncoprotein expression was found in these 2 high p53 expressers in which p53 mutation was not present, but not in low p53 expressers or cells carrying this mutation. The levels of p53 mRNA were similar among the samples regardless of p53 levels. Posttranscriptional mechanisms other than missense mutation would thus appear to increase p53 in the Tax‐expressing cells hut not in cells containing undetectablc levels of Tax. No complex formation between p53 and Tax was observed.
Random Process of Metastasis and Generation of Heterogeneity in a Mouse Sarcoma Line
Authors: Niwa Ohtsura , Enoki Yoshitaka , Sadamoto Seiji , Kamiya Kenji , Yokoro Kenjiro
Published: August 2005

The process of metastasis was analyzed in 505‐05‐01 cells, an established line of a methylcholanthrene‐induced mouse sarcoma, by tagging the cells with the pSV2neo plasmid. A dominant clone was identified which, upon transplantation together with other clones, overgrew tumors in the kidney capsule. However, when this clone was transplanted in a mouse collaterally with recessive clones, both clones grew at the same rate and metastasized to the lung at an equal frequency. This suggests that the process of metastasis in this particular sarcoma line is stochastic, the dominant population having a better chance to colonize to the lung. The dominant neomycin‐resistant clone was transfected with another marker plasmid, pY3, which confers resistance to hygromycin. Results of mixed inoculation of 9 independently isolated clones revealed the hierarchy of dominance among clones. This indicated the existence of heterogeneity within the parental clone. Upon mixed inoculation with hygromycin‐resistant clones, the parental clone overgrew in the tumors. This indicated that some clone had changed its phenotype to become less aggressive. Thus, the direction of phenotypic drift in vitro seems to be random in terms of behavior in vivo.
Characterization of Mammary Plaques in DDD Mice Congenic for Mtv‐2 Gene, DDD/1‐Mtv‐2/Mtv‐2
Authors: Matsuzawa Akio , Kaneko Tetsuya , Takeda Yasutaka , Murakami Akira , Tsubura Airo
Published: August 2005

DDD/1 mice free from exogenous mouse mammary tumor virus (MMTV) do not develop any neoplastic mammary lesions. In GR mice, the expression of Mtv‐2, an endogenous proviral MMTV, leads to 100% incidence of mammary ductal hyperplasias and tumors. An Mtv‐2 congenic line, DDD/1‐Mtv‐2/Mtv‐2, was established by introducing Mtv‐2 from GR into DDD/1 to elucidate its function. Development of mammary plaques (MPQ) characterized by ductal hyperplasias was investigated in 152 congenic females on day 17 to 19 of the first pregnancy. The incidence of MPQ was 48.0% and most MPQ‐positive mice (75.3%) had only one MPQ. Generally, MPQ were small in size: the diameter was as small as ≦3 mm in 77.6% of them. Of 84 MPQ implanted into intact fat pads, 43 (51.2%), 38 (45.2%) and 3 (3.6%) showed undetectable, pregnancy‐dependent and autonomous growths; respectively when the hosts underwent pregnancy. Almost all MPQ produced normal‐appearing ductal‐alveolar outgrowths in mammary epithelium‐divested or cleared fat pads of virgins. MPQ implanted into cleared fat pads were very similar to normal mammary glands in the responses to progesterone (P) and estradiol (E) alone or in combination except for association of ductal hyperplasias in 4 of 12 MPQ under E+P treatment. These findings revealed the preneoplastic nature of MPQ. Exogenous MMTV proviruses were demonstrated in all MPQ. The int‐2 DNA rearrangement was found in 2 of 10 MPQ but in none of 9 mammary carcinomas and the int‐1 DNA rearrangement in none of 10 MPQ but in 5 of 10 carcinomas. It is thus likely that the Mtv‐2 gene participates in a very early stage of mammary tumorigenesis not directly but indirectly through insertion mutation of host genes, while the cellular oncogenes, int‐2 and int‐1, may contribute to preneoplastic transformation of mammary epithelium and progression from preneoplastic to more malignant states, respectively.
A Very Low Dose of Green Tea Polyphenols in Drinking Water Prevents N‐Methyl‐N‐nitrosourea‐induced Colon Carcinogenesis in F344 Rats
Authors: Narisawa Tomio , Fukaura Yoko
Published: August 2005

The effect of tea polyphenols, major constituents of tea, on colon carcinogenesis was investigated. A total of 129 female F344 rats were given an intrarectal instillation of 2 mg of N‐methyl‐N‐nitrosourea 3 times a week for 2 weeks, and received a water solution of green tea extract (GTE) as drinking water throughout the experiment. Autopsies at week 35 revealed significantly lower incidence of colon carcinomas in rats ingesting 0.05%, 0.01% or 0.002% GTE solution than in controls ingesting 0% GTE solution: 43%, 40% and 33% vs. 67%. The data suggest that GTE, even at a very low dose (0.002% solution), has a potent inhibitory effect on colon carcinogenesis.