bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure‐Function Relationships of Microcystins, Liver Tumor Promoters, in Interaction with Protein Phosphatase
Authors: Nishiwaki‐Matsushima Rie , Nishiwaki Shinji , Ohta Tetsuya , Yoshizawa Seiji , Suganuma Masami , Harada Ken‐ichi , Watanabe Mariyo F. , Fujiki Hirota
Published: August 2005

Microcystins, isolated from toxic blue‐green algae, are potent inhibitors of protein phosphatases 1 and 2A. Recently, we have reported that mierocystin LR has a potent tumor‐promoting activity on rat liver initiated with diethylnitrosamine. The structure of microcystins is unique in having an unusual ammo acid, 3‐amino‐9‐methoxy‐10‐phenyl‐2,6,8‐trimethyl‐deca‐4(E),6(E)‐dienoic acid (Adda), which is thought to be significant for the activity. Geometrical isomers at C‐7 in the Adda portion of microcystins, 6(Z)‐Adda microcystins LR and RR, have been isolated from cyanohacteria. To estimate their tumor‐promoting activities and to understand the importance of the Adda portion for activity, the maternal microcystins LR and RR and their isomers were subjected to examination of their interaction with protein phosphatases 1 and 2A and the release of glutamic pyruvic transaminase from rat liver. 6(Z)‐Adda microcystins LR and RR bound to protein phosphatases 1 and 2A, inhibited their activities and released glutamic pyruvic transaminase from rat liver into serum, ten to one hundred times more weakly than the maternal microcystins LR and RR. These results indicated that the conjugated diene with 4(E),6(E) geometry in the Adda portion is important in the interaction with protein phosphatases.
Frequent Loss of Heterozygosity at the MCC Locus on Chromosome 5q21‐22 in Sporadic Colorectal Carcinomas
Authors: Miki Yoshio , Nishisho Isamu , Miyoshi Yasuo , Horii Akira , Ando Hiroshi , Nakajima Toshifusa , Utsunomiya Joji , Nakamura Yusuke
Published: August 2005

Recent studies have identified a gene on chromosome 5q, designated MCC (mutated in colorectal cancers), as a candidate for the putative colorectal tumor suppressor gene that is located at 5q21. We examined loss of heterozygosity (LOH) at the MCC locus and its vicinity in sporadic colorectal carcinomas, using 12 RFLP (restriction fragment length polymorphism) markers. One clone, L5.71, had been used to identify the MCC gene; all 12 markers also had tight linkage to the gene responsible for adenomatous polyposis coli. All 40 cases studied were informative with at least one marker, and 22 of them (55%) showed LOH at one or more loci. LOH in the tumors was more frequent in the immediate vicinity of L5.71 than in distant parts of the chromosome, and a common region of deletion was detected between markers L5.62 and 15A6. In one case, alleles were retained at L5.71 and at loci proximal to L5.71, but alleles were lost at loci distal to L5.71. In another case, both alleles were retained at L5.71 but alleles were lost at loci proximal and distal to L5.71. These results support the conclusion that a tumor suppressor gene for colorectal carcinoma is located within or around locus L5.71.
Morphometrical Analysis of Structural Abnormality of Tubular Tumors of the Stomach with Image Processing
Authors: Ishido Tatsuya , Yamaguchi Hajime , Yoshida Shigeaki , Tonouchi Shin , Nakamura Kyoichi
Published: August 2005

Four indices, index of tubular density, index of dispersion of tubular size, degree of complexity of tubular shape and frequency of complex‐shaped tubuli, were defined to quantify the structural abnormalities of gastric tumors in morphometrical analysis by image processing. The values of each index corresponded well with the degree of each structural abnormality found pathologically. These indices were considered to be valid for representing their respective structural factors. There were significant differences among the mean values of the scores calculated by a formula using all 4 indices of benign tubular adenoma, borderline lesion and well‐differentiated type tubular adenocarcinoma (P<0.05). Therefore, the discriminant formula was considered to be valid for integrating these indices and for representing structural abnormality of gastric tubular tumors.
In vitro Anti‐human Immunodeficiency Virus Type 1 Activity of Biliverdin, a Bile Pigment
Authors: Mori Haruyo , Otake Toru , Morimoto Motoko , Ueba Noboru , Kunita Nobuharu , Nakagami Tatsuyoshi , Yamasaki Non , Taji Shiro
Published: August 2005

Biliverdin (BY) is a bile pigment having anti‐allergic properties. We examined the effect of BV on human immunodeficiency virus type 1 (HIV‐1) in vitro. BV completely inhibited the cytopathic effect of HIV‐1 in MT‐4 cells at concentrations of 22.2 μg/ml or more. This inhibitory effect was also observed when BV was present during the adsorption period of HIV‐1. However, BV was cytotoxic to MT‐4 cells at concentrations above 800 μg/ml. At a concentration of 66.7 μg/ml, BV completely inhibited syncytia formation by HIV‐infected and uninfected MOLT‐4 cells. Moreover, after exposure of HIV‐1 particles to BV for 2 h, the infectivity of the virus was reduced in a dose‐dependent manner. It is speculated that the anti‐HIV activity of BV is due to direct inactivation of virions and inhibition of virus binding to target cells.
Effects of 3‐Aminobenzamide on Induction of Multiorgan Carcinogenesis by N‐Nitrosobis(2‐hydroxypropyl)amine in Hamsters
Authors: Tsujiuchi Toshifumi , Tsutsumi Masahiro , Denda Ayumi , Amanuma Toshihiro , Kondoh Satoshi , Kamino Kenji , Konishi Yoichi
Published: August 2005

The effects of an inhibitor of poly(ADP‐ribose)polymerase, 3‐aminobenzamide (ABA), on N‐nitrosobis(2‐hydroxypropyl)amine (BHP)‐induced pancreas, liver, gallbladder and lung carcinogenesis in Syrian golden hamsters were investigated. Animals were given either BHP alone, by subcutaneous injection at a dose of 500 mg/kg body weight, or in combination with an intraperitoneal injection of ABA 30 min after the BHP at a dose of 300 or 600 mgAg body weight once a week for 5 weeks, and then killed 35 weeks after the commencement of the experiment. ABA exerted inhibitory effects on pancreas and lung carcinogenesis induced by BHP, with mean numbers of lesions (including hyperplasias and carcinomas) being significantly decreased compared with the BHP‐alone group values, while no significant effect was observed on liver or gallbladder carcinogenesis. These results suggest that the effects of ABA on carcinogenesis depend on the target organ as well as the chemical carcinogen examined.
Site‐dependent Development of Complete and Incomplete Intestinal Metaplasia Types in the Human Stomach
Authors: Kato Yo , Kitagawa Tomoyuki , Yanagisawa Akio , Kubo Kiyoko , Utsude Tomoya , Hiratsuka Hideo , Tamaki Masahiro , Sugano Haruo
Published: August 2005

The topographical distribution of complete and incomplete types of intestinal metaplasia in human stomach samples was investigated in order to elucidate their mutual histogenetic relationship and significance in carcinogenesis. Subgross stereomicroscopic examination of alcian blue and hematoxylin‐stained gastric mucosae allowed clear distinction of complete and incomplete intestinal metaplasia types as white (with or without purple hue) and purple foci, respectively, against the background magenta areas of non‐intestinalized mucosa. Intestinal metaplasias which developed in the fundic area were predominantly of the complete type whereas those of the antrum were a mixture of both with a distinct predilection for expression of the incomplete type. Although there was some variation among foci regarding the hue of white or purple, the color feature was principally homogeneous within each individual intestinal metaplasia focus. Thus phenotypic analysis indicated intestinal metaplasia expression to be clearly influenced by intragastric topography. The study did not provide any evidence that a shift from incomplete to complete type intestinal metaplasia may occur with time or that the incomplete type may be more intimately associated with development of well‐differentiated carcinomas.
HTLV‐I Uveitis: A Distinct Clinical Entity Caused by HTLV‐I
Authors: Mochizuki Manabu , Watanabe Toshiki , Yamaguchi Kazunari , Takatsuki Kiyoshi , Yoshimura Koichi , Shirao Makoto , Nakashima Shunsuke , Mori Shigeo , Araki Shinji , Miyata Norio
Published: August 2005

Seroepidemiological, clinical and virological studies were carried out in an HTLV‐I endemic area to find out if HTLV‐I caused an intraocular inflammatory disorder, uveitis. The seroprevalence in patients with uveitis without defined etiologies (62/175, 35.4%) was significantly higher than that in patients with non‐uveitic ocular diseases (42/261, 16.1%) or in patients with uveitis with defined etiologies (8/78, 10.3%). Moreover, the seroprevalence in young adults (20–49 years) with uveitis without defined etiologies was 30/67 (44.8%), whereas it was only 10/107 (9.3%) in the other two groups. The uveitis in HTLV‐I carriers was characterized clinically by a moderate inflammation of the vitreous body accompanied by a mild iritis and retinal vasculitis. The proviral DNA of HTLV‐I was detected by polymerase chain reaction from the inflammatory cells in the anterior chamber in 9 out of 9 seropositive patients with the uveitis, but not in any of the tested patients with other types of uveitis. These data, thus, indicate that HTLV‐I causes a specific type of intraocular inflammation, uveitis.
Liver Carcinogencsis by Methyl Carbamate in F344 Rats and Not in B6C3F1 Mice
Authors: Chan Po C. , Huff James , Haseman Joseph K. , Quest John A. , Hall William
Published: August 2005

Short‐term and long‐term carcinogenicity of methyl carbamate (MCB) was evaluated in F344 rats and B6C3F1 mice. In experiments lasting 6, 12, and 18 months, MCB was given in water by gavage to groups of 10 male and 10 female rats at 0 or 400 mg/kg body weight, 5 days per week, and to similar groups of mice at 0 or 1,000 mg/kg. At 6 months, MCB induced atypical mitoses, cytologic alterations, cytomegaly, pigmentation, necrosis, and neoplastic nodules of the liver in rats. At 12 and 18 months, carcinomas of the liver were induced by MCB in 80–90% of male rats and in 60–80% of female rats. None was observed in control rats or in mice. In the 2‐year studies, MCB was given to groups of 50 male and 50 female rats at 0, 100, or 200 mg/kg and to similar groups of mice at 0, 500, or 1,000 mg/kg, 5 days/week. Chronic focal inflammation, cytologic alteration, hyperplasia, and neoplastic nodules and carcinomas (200 mg/kg groups only) of the liver were induced by MCB in rats. Liver tumor incidence data for combined experiments in rats were: males — 5% in controls, 0% in 100 mg/kg group, 14% in 200 mg/kg group, and 77% in 400 mg/kg group; females — 0% in controls, 0% in 100 mg/kg group, 12% in 200 mg/kg group, and 63% in 400 mg/kg group. MCB was not shown to be carcinogenic in mice.
Morphometrical Analysis of Nuclear Abnormality of Tubular Tumors of the Stomach with Image Processing
Authors: Ishido Tatsuya , Yamaguchi Hajime , Yoshida Shigeaki , Tonouchi Shin
Published: August 2005

Nuclear size and shape on histological specimens were used to quantify nuclear abnormality in gastric tubular tumors. A valid technique for this morphometrical analysis by image processing was developed. Furthermore, the present study examined the nuclear size and shape to determine if they were reliable criteria to be used for differential diagnosis. Nuclear area, maximum diameter and maximum width on the histological specimens were defined as factors to represent nuclear size. Nuclear aspect ratio represented nuclear shape. Histological features revealed varied degrees of condensation of nuclei; this was due to different protocols for preparing the histological specimens. This finding indicated that the size of intermediate lymphocytes on the same specimens should be measured as a control in order to estimate the degree of nuclear condensation. The present study also demonstrated that at least 200 nuclei should be measured on the histological specimens to obtain accurate nuclear size and shape. Histologically, the nuclei in benign tubular adenoma and borderline lesions tended to be spindle‐shaped, while those in well‐differentiated type tubular adenocarcinoma tended to be round and swollen. The nuclei in borderline lesions were larger than those in benign tubular adenoma and smaller than those in well‐differentiated type tubular adenocarcinoma. Our results for the above 4 factors corresponded well with these histological findings. The nuclear size and shape on histological specimens were concluded to be reliable criteria for assessing nuclear abnormality in gastric tubular tumors and useful ones for differential diagnosis.
Antitumor Activity and Cellular Accumulation of a New Platinum Complex, (—)‐(R)‐2‐Aminomethylpyrrolidine(1,l‐cyclobutanedicarboxylato)platinum(II) Monohydrate, in Cisplatin‐sensitive and ‐resistant Murine P388 Leukemia Cells
Authors: Kamisango Keiichi , Matsumoto Tomoko , Akamatsu Ken‐ichi , Morikawa Kazumi , Tashiro Tazuko , Koizumi Kinya
Published: August 2005

We have examined the cytotoxicity and accumulation of (—)‐(U)‐2‐aminomethylpyrrolidine(1,l‐cyclobutanedicarboxylato)platinum(II) monohydrate (DWA2114R) in parent and cisplatin‐resistant mouse P388 leukemia cells (P388 and P388/DDP), in comparison with those of cisplatin (CDDP) and carboplatin (CBDCA). The degrees of resistance to CDDP and CBDCA, expressed as the ratio of IC50for P388/DDP celts to IC50 for P388 cells, were 75–33 and 100‐27, respectively, under the conditions of 2–24 h exposure to each drug at a density of 106 cells/ml. The corresponding values (25–7) for DWA2114R were relatively low. Accumulations of CDDP and CBDCA were reduced in P388/DDP cells; however, no reduction in accumulation of DWA2114R was observed at various exposure periods and concentrations of the drugs. The accumulations of CDDP in P388 and P388/DDP cells at drug concentrations corresponding to the IC50 values for drug exposure periods of 2–24 h were 0.41–0.97 and 13.1–33.7 ng Pt/107 cells, respectively, suggesting that an intracellular mechanism of resistance against CDDP could be activated in P388/DDP cells. P388/DDP cells also showed relatively low resistance to DWA2114R via this mechanism in comparison with CDDP and CBDCA. From the relationship between structure and activity of several Pt‐complexes, these different properties of DWA2114R compared with CDDP and CBDCA could be due not only to the differences in carrier ligand structure but also to the properties of the whole molecule associated with the carrier ligand and leaving group.
Direct Detection of Epstein‐Barr Virus DNA from a Single Reed‐Sternberg Cell of Hodgkin's Disease by Polymerase Chain Reaction
Authors: Teramoto Norihiro , Akagi Tadaatsu , Yoshino Tadashi , Takahashi Kiyoshi , Jeon Ho Jong
Published: August 2005

Eleven cases of Hodgkin's disease (HD) were examined for the presence of the Epstein‐Barr virus (EBV) genome, using the polymerase chain reaction (PCR) to detect EBV DNA in whole paraffin‐embedded tissue specimens and in single cells picked out from the specimens with a micromanipulator. The EBV genome was detected in 5 of the 11 cases by conventional PCR. Single cell PCR demonstrated the EBV genome in Reed‐Sternberg cells from all the EBV‐positive cases, but not from any of the EBV‐negative cases. Background lymphocytes and lysozyme‐positive histiocytes from EBV‐positive cases did not contain the EBV genome. These results indicate an etiological association of EBV with some cases of HD.
Second Primary Cancer Following Laryngeal Cancer with Special Reference to Smoking Habits
Authors: Hiyama Tomohiko , Sato Takeo , Yoshino Kunitoshi , Tsukuma Hideaki , Hanai Aya , Fujimoto Isaburo
Published: August 2005

The risk of developing a second primary cancer following laryngeal cancer was estimated by following‐up 472 male laryngeal cancer patients for an average of 8.6 years by means of record linkage to the Osaka Cancer Registry. Of these patients, 115 developed a second cancer other than laryngeal cancer, whereas the expected number derived from the incidence rates among Osaka residents was 51.4 (relative risk (RR) = 2.2, 95% confidence interval = 1.85 2.69). Cumulative risk of developing a second primary cancer was estimated to be 31.1% at 15 years after laryngeal cancer. By site, the risks were significantly increased for tobacco‐related cancers, RR = 24.5, 6.1 and 2.3 for cancers of the oral cavity & pharynx, esophagus and lung, respectively. Also, the risks were higher among heavy smokers for cancer of the oral cavity & pharynx and esophagus than among light smokers. No adverse effects of radiotherapy for laryngeal cancer on the development of thyroid cancer, lymphoma and leukemia were observed. The present study suggests the necessity of following‐up laryngeal cancer patients over a long period in order to enable the early detection of tobacco‐related cancer.
Reversibility of Carcinogen‐induced Rat Forestomach Basal Cell Hyperplasia Is Due to Squamous Cell Differentiation
Authors: Ogawa Kumiko , Hoshiya Toru , Kato Toshio , Shirai Tomoyuki , Tatematsu Masae
Published: August 2005

The mechanisms of reversibility of basal cell hyperplasia in the rat forestomach were investigated. Male F344 rats were given an initial single gastric intubation of N‐methyl‐N′‐nitro‐N‐nitoroso‐guanidine and then received 2% butylated hydroxyanisole in the diet from the third week to the 26th week. Rats were killed at weeks 26 and 46 after return to basal diet and their forestomachs were removed. Bromouracil deoxyriboside (BUdR) was administered as a single i.p. injection 1 h before death or by osmotic minipump (120 μg/h) continuously for 7 days before death. Additional animals were maintained for 2 or 4 weeks after removal of osmotic minipumps to allow assessment of the fate of proliferating populations. In each case BUdR‐labeled cells were demonstrated by immunohisto‐chemistry. At week 26, hyperplastic changes were more pronounced than at week 46. Squamous cells above basal cell hyperplasias were strongly labeled even 4 weeks after cessation of continuous BUdR administration, in clear contrast to those in normal‐appearing epithelium. Three‐dimensional reconstruction of persisting basal cell hyperplasias showed almost all basal cells limited to a thin sheet in direct contact with the squamous cell layer, occasional separate islands demonstrating differentiation to squamous cells and formation of epidermal cysts. The results thus showed that the mechanism of reversibility of basal cell hyperplasia involves differentiation of basal cells to squamous cells.
Myeloprotective Activity of Deoxyspergualin: Influence on Splenic Colony‐forming Cell Injury and Antitumor Activity of Mitomycin C in Mice
Authors: Nemoto Kyuichi , Sugawara Yumi , Ogino Miwa , Mae Takako , Abe Fuminori , Takeuchi Tomio
Published: August 2005

We have examined the efficacy of deoxyspergualin (DSG) in protecting splenic colony‐forming cells (CFU‐S) from mitomycin C (MMC)‐induced damage. The main findings of the study are as follows. (1) When DSG was administered at doses of 1.5 and 3 mg/kg for 7 days before the MMC injection, the decrease of the femoral CFU‐S caused by MMC was diminished on the day after the MMC injection. The optimal dose was found to be 3 mg/kg. (2) In animals receiving 3 mg/kg DSG for at least 3 days preceding the MMC injection, the femoral CFU‐S was more than 200% of that in the MMC alone group one day after the MMC injection. (3) The number of femoral CFU‐S in the mice which received 3 mg/kg DSG for 3 days prior to MMC was significantly restored day by day and reached 70% of normal at 5 days after the MMC injection, while it was only 13% of normal in the MMC alone group. Moreover, the prior DSG administration significantly diminished the MMC toxicity to circulating platelets. (4) DSG administration (3 mg/kg) 3 days prior to MMC did not weaken the antitumor activity against colon 26 adenocarcinoma or P388 leukemia when compared with MMC alone. These findings have shown the ability of DSG specifically to protect the animals against bone marrow toxicity caused by MMC without interfering with the antitumor activity.
A Case‐Control Study of Single and Multiple Stomach Cancers in Saitama Prefecture, Japan
Authors: Hoshiyama Yoshiharu , Sasaba Takafumi
Published: August 2005

A case‐control study of stomach cancer was done in Saitama Prefecture, Japan, in relation to dietary, smoking, and drinking habits. The study was based on two sets of cases (216 male single and 35 male multiple stomach cancer cases newly diagnosed and of adenocarcinoma type), and 483 male controls derived from residents of Saitama Prefecture. Dietary habits were investigated for the intake of 12 separate foods and 12 food groups by means of a food frequency questionnaire, including individual taste preferences. Among the single stomach cancer series, dose‐response relationships were observed for 7 dietary items (preference for salty foods, miso soup, boiled fish, pickled vegetables, nuts, raw vegetables, and seaweed) in the multiple logistic regession analysis. As for the multiple stomach cancer case series, dose‐response relationships were observed for 3 dietary items (miso soup, fruits, and seaweed) in the multiple logistic regression analysis. Cigarette smoking and alcohol use were not significantly related to the risk of either single or multiple stomach cancer.
Delayed DNA Synthesis Induced by 3‐Aminobenzamide in Partially Hepatectomized Liver of Rats
Authors: Tsujiuchi Toshifumi , Tsutsumi Masahiro , Uchida Kazuhiko , Honoki Kanya , Kondoh Satoshi , Denda Ayumi , Miwa Masanao , Konishi Yoichi
Published: August 2005

The possibility of poly(ADP‐ribosyl)ation playing a role during liver regeneration induced by partial hepatectomy (PH) in vivo was examined. When rats were given an i.p. injection of 3‐antinobenzamide (ABA) at a dose of 600 mg/kg body weight 12 h after PH, the levels of DNA synthesis at 20 h after PH were significantly reduced. The time course of DNA synthesis in regenerating liver was significantly delayed in the ABA‐treated group. Enzymatic assay revealed the activity of poly‐(ADP‐ribose)polymerase (PADPRP) in controls to be increased in parallel with the increase of DNA synthesis induced by PH. This increase in PADPRP activity was delayed and very much weaker after ABA treatment. The results thus suggested that poly (AUP‐ribosyl)ation might play an important role in DNA synthesis during liver regeneration in vivo.
Adduct Formation at C‐8 of Guanine on in vitro Reaction f the Ultimate Form of 2‐Amino‐l‐methyl‐6‐phenylimidazo[4,5‐b]pyridine with 2′‐Deoxyguanosine and Its Phosphate Esters
Authors: Nagaoka Hiroaki , Wakabayashi Keiji , Kim Seon‐Bong , Kim In‐Soo , Tanaka Yoshino , Ochiai Masako , Tada Akihiro , Nukaya Haruo , Sugimura Takashi , Nagao Minako
Published: August 2005

We examined the reactivity of the N‐hydroxyamino derivative of a carcinogenic heterocyclic amine, 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP), after its O‐acetylation with four 2′‐deoxyribonucleoside 3′‐monophosphates. 32P‐Postlabeling analysis demonstrated that the levels of adducts with 2′‐deoxyguanosine 3′‐moiiophosphate were much higher than those with the other three nucleotides. 1H‐NMR, mass spectral and UV absorption spectral analyses of the major adducts formed by N‐acetoxy‐PhIP with 2′‐deoxyguanosine and with its phosphate esters indicated that PhIP bound at the C‐8 position of guanine, as previously demonstrated with other heterocyclic amines.
Detection of p53 Gene Mutations in Human Ovarian and Endometrial Cancers by Polymerase Chain Reaction‐Single Strand Conformation Polymorphism Analysis
Authors: Naito Mariko , Satake Masanobu , Sakai Eiki , Hirano Yasumasa , Tsuchida Nobuo , Kanzaki Hideharu , Ito Yoshiaki , Mori Takahide
Published: August 2005

The presence of mutations in the p53 gene was examined in ovarian cancers by a polymerase chain reaction‐single strand conformation polymorphism (PCR‐SSCP) analysis. The primers were designed to amplify exons 5 through 9 that contain phylogenetically conserved domains of the p53 gene. Mutations were detected in 5 out of 10 cases, one of which contained a deletion in the second allele. A single base substitution was detected in 4 cases at codons 162,175, 205 and 273 and a single base insertion in one case within codon 315. A high frequency of p53 mutations in ovarian cancers and lack of mutation in 6 benign ovarian tumors and 2 normal ovaries suggested that the mutation of the p53 gene was associated with the genesis and/or progression of ovarian cancer. In 1 of 7 endometrial cancers, two mutations at codons 239 and 254 were detected.
ras Mutations in Endocrine Tumors: Mutation Detection by Polymerase Chain Reaction‐Single Strand Conformation Polymorphism
Authors: Yoshimoto Katsuhiko , Iwahana Hiroyuki , Fukuda Ayumi , Sano Toshiaki , Katsuragi Kiyonori , Kinoshita Moritoshi , Saito Shiro , Itakura Mitsuo
Published: August 2005

To elucidate the molecular basis for endocrine tumorigenesis, ras mutations in human endocrine tumors were analyzed using polymerase chain reaction‐single strand conformation polymorphism (PCR‐SSCP) analysis. Mutations of the H‐, K‐, N‐ras genes were examined in genomic DNAs from 169 successfully amplified primary endocrine tumors out of 189 samples. Four out of 24 thyroid follicular adenomas analyzed contained mutated N‐ras codon 61, and one contained the mutated H‐ras codon 61. One of the 19 pheochromocytomas revealed mutation of the H‐ras codon 13. No mutations of the ras gene were detected in pituitary adenomas, parathyroid tumors, thyroid cancers, endocrine pancreatic tumors, and adrenocortical tumors. Based on these findings we conclude that activation of the ras gene may play a role in the tumorigenesis of a limited number of thyroid follicular adenomas and pheochromocytomas, and that mutation of the ras gene is not frequent in other human endocrine tumors.
Human Carcinoma Cells Synthesize and Secrete Tenascin in vitro
Authors: Kawakatsu Hisaaki , Shiurba Robert , Obara Masanobu , Hiraiwa Hideki , Kusakabe Moriaki , Sakakura Teruyo
Published: August 2005

Tenascin is an extracellular matrix glycoprotein produced in response to epithelial‐mesenchymal interactions that initiate fetal organogenesis, and it is also found in the stroma of benign and malignant neoplasms. Thirty‐five human cell lines representing a variety of cancers were examined by im‐munoprecipitation and polyacrylamide gel electrophoresis of radiolabeled tenascin proteins from conditioned media. Two forms of tenascin with relative molecular masses of 190,000 and 250,000 were identified. Eight cell lines produced both forms. With the exception of myeloid and lymphoid leukemias and Burkitt's lymphoma, all of the mesodermal and neuroectodermal tumor lines were found to synthesize tenascin. Unexpectedly, tenascin was secreted by several mammary and colonic adenocarcinomas as well as by a line derived from normal mammary epithelial cells, and in some cases increased production was induced by transforming growth factor beta in serum‐free medium. Cells producing fibronectin but not tenascin attached and spread on plastic culture dishes, while those producing tenascin alone remained suspended in the medium or were rarely attached. Tenascin also inhibited fibronectin‐mediated adhesion of MCF7 breast carcinoma cells in vitro. The results suggest that tenascins synthesized and secreted by some cancer cells, especially those of epithelial origin, may have specific roles in determining tumor cell adhesion and ultimately the ability to form invasive outgrowths.
Optimal Electric Conditions in Electrical Impulse Chemotherapy
Authors: Okino Motonori , Tomie Hiroshi , Kanesada Hirohiko , Marumoto Masaru , Esato Kensuke , Suzuki Hiroshi
Published: August 2005

The relationship was examined between the tumoricidal effect and the electrical variables of in vivo electrical impulse chemotherapy. Donryu rats subcutaneously inoculated with AH‐109AY hepatocellular carcinomas were given a single high‐voltage electrical impulse of varying voltage and duration, 30 min after an intramuscular injection of 4 mg/kg bleomycin. As the voltage (V) was increased from 0 to 5 kV, the tumoricidal effect (E) increased in proportion to the square of the voltage. As the pulse duration (D) was increased from 2.5 to 5.8 ms, the tumoricidal effect increased in direct proportion to it. Combining these results yielded the formula, E=γV2D, which indicates that tumoricidal efficacy was proportional to the applied electrical energy. When the electrical energy was kept constant while varying the voltage and duration of pulse, the anticancer effect was the same, confirming this relationship for lower energy levels.
Potentiation of Topoisomerase I and II Inhibitors Cell Killing by Tumor Necrosis Factor: Relationship to DNA Strand Breakage Formation
Authors: Orengo Giorgia , Noviello Elvira , Cimoli Guido , Pagnan Gabriella , Parodi Silvio , Venturini Marco , Conte Pier Franco , Schenone Federico , Conzi Gianfranco , Russo Patrizia
Published: August 2005

Recombinant human tumor necrosis factor (rHuTNF) synergistically potentiates the cytotoxicity of the topoisomerase I inhibitor camptothecin, and the topoisomerase II inhibitors epidoxorubicin, etoposide, mitoxantrone, ellipticine, actinomycin D and 4′‐(9‐acridinylamino)methanesulfon‐m‐anisidide on A2780 human ovarian cancer cell line. Similar synergy was not observed with a combination of rHuTNF and cis‐platinum or mitomycin C. When A2780 cells were incubated with rHuTNF simultaneously with camptothecin or mitoxantrone or VP16, increased numbers of DNA single‐strand breaks were produced. rHuTNF alone did not induce DNA strand breakage. These data provide evidence that the enhancing effect of rHuTNF is closely related to the DNA damage mediated by topoisomerase‐targeted drugs. These observations may have relevance for ovarian cancer treatment.
Flow Cytometric Analyses of the Characteristics of Tumor Cells Treated with Two Platinum Compounds: 1,1‐Cyclobutanedicarboxylato(2‐aminomethylpyrrolidine)‐platinum(II) and Cisplatin
Authors: Inoue Shoichi , Mizuno Shigetaka , Ito Masami , Ohnuma Takao
Published: August 2005

In order to reduce the toxicities of cisplatin (DDP) and/or to improve antitumor efficacy, a large number of new platinum analogues have been synthesized. 1,1‐Cyclobutanedicarboxylato(2‐amino‐methylpyrrolidine)platinum(II) (DWA2114R) is one of them. In this study, we characterized the action mechanism of DWA2114R flow‐cytomctrically in 3 human lung cancer cell lines by using bromodeoxyuridine (BrdUrd), rhodamine 123 (Rho) and Ki‐67 antibody (Ab), and compared the results with those for DDP. We found that the actions of these 2 platinum analogues were characteristically different at the subcellular level. Our observations may be summarized as follows, a) Simultaneous exposure of cells to DDP and BrdUrd resulted in decreases in fluorescence intensity, i.e. in the amount of BrdUrd incorporated into single‐stranded DNA. b) DDP appears to be approximately 20‐fold more active than DWA2114R in producing cell cycle perturbation, c) In PC‐6 small cell carcinoma cells, DDP induced decreases in S phase cells and accumulation of cells in the G2M phase, whereas in PC‐10 squamous carcinoma and PC‐3 adenocarcinoma cells DDP produced S phase cell accumulation. Weak but similar changes occurred with DWA2114R. d) The high Ki‐67 antigen cell population was decreased by treatment with either DDP or DWA2114R, but DDP reduced the low Ki‐67 antigen population more than DWA2114R. e) In PC‐10 and PC‐d cells, DDP suppressed Rho incorporation into live mitochondria, whereas DWA2114R produced no change in Rho incorporation. PC‐3 cells were not affected by either DDP or DWA2114R. It is likely that these differences reflect the biological activities of DDP and DWA2114R.
Retrovirus‐mediated Gene Transfer Targeted to Malignant Glioma Cells in Murine Brain
Authors: Yamada Masanobu , Shimizu Keiji , Miyao Yasuyoshi , Hayakawa Toru , Ikenaka Kazuhiro , Nakahira Kensuke , Nakajima Kazunori , Kagawa Tetsushi , Mikoshiba Katsuhiko
Published: August 2005

A murine model for meningeal metastasis of malignant glioma was developed to study selective gene transfer into tumor cells and to establish a reliable means of determining the rate of tumor cell infection. A murine ecotropic retroviral vector was created in which the Escherichia coliβ‐galactosidase gene served as a marker for gene expression from the integrated retrovirus. This retrovirus exhibited a high rate of infectivity in RSV‐M mouse glioma cells in vitro. The recombinant retrovirus was injected directly into the cisterna magna of the mice. Staining of β‐galactosidase showed that the rate of gene integration was high in the disseminated glioma cells. These results suggest the possibility of retrovirus‐mediated gene therapy for meningeal dissemination of malignant glioma.
Sensitive Detection of p53 Gene Mutations in Esophageal Endoscopic Biopsy Specimens by Cell Sorting Combined with Polymerase Chain Reaction Single‐strand Conformation Polymorphism Analysis
Authors: Maesawa Chihaya , Tamura Gen , Suzuki Yasushi , Ishida Kaoru , Saito Kazuyoshi , Satodate Ryoichi
Published: August 2005

For the rapid and sensitive detection of p53 gene mutations in esophageal endoscopic biopsy specimens, we combined cell sorting with the polymerase chain reaction and single‐strand conformation polymorphism (PCR‐SSCP) analysis. Mutations in exons 5–8 of the p53 gene were investigated by FCR‐SSCF analysis using 103 sorted nuclei obtained from each endoscopic biopsy specimen of 16 patients with esophageal cancer. DNAs extracted from their respective surgical specimens were investigated by a conventional method of PCR‐SSCP analysis. Mutations in the biopsy specimens were detected in 6 of the 12 aneuploid tumors but in none of the 4 diploid tumors. After tumor cell enrichment by cell sorting, one mutation in exon 8 became apparent, which could not be detected from the surgical specimen by a conventional method of PCR‐SSCP analysis. This method should improve the sensitivity of detecting p53 gene mutations, and provides additional information concerning the DNA ploidy pattern in the tumors.
Variation in K‐ras Codon 12 Point Mutation Rate with Histological Atypia within Individual Colorectal Tumors
Authors: Sob Kontae , Yanagisawa Akio , Hiratsuka Hideo , Sugano Haruo , Kato Yo
Published: August 2005

To elucidate genetic alteration in relation to morphology and also to confirm more directly the proposed adenoma‐carcinoma sequence, we analyzed thirty‐eight colorectal “cancer in adenoma” lesions exhibiting areas of different atypia, in terms of K‐ras codon 12 point mutation. The mutation incidence was 26.3% (10/38) for all cancerous areas. Well‐differentiated and very well‐differentiated carcinoma exhibited values of 17.6% (3/17) and 30.4% (7/23), respectively (statistically not significant). Positive cases of adenoma with severe atypia and adenoma with moderate or slight atypia were 26.7% (8/30) and 8.3% (3/36) respectively (statistically significant). Thus, K‐ras point mutation, as indicated previously, may play an important role in the early stages of colorectal tumorigenesis. As for the nature of the mutation, GGT(Gly) to GAT(Asp) was the most frequent (80%). Eight cases had mutations concurrently in different areas of the same tumor and in all of these the mutation was homogeneous (6 cases to GAT, 1 case to TGT and 1 case to GTT). This provides genetic support for the “adenoma‐carcinoma sequence” theory proposed on the basis of morphological considerations. All lesions with a mutation were of polypoid type, and no mutation was found in the flat type.
The Expression of Invasive Behavior of Differentiated Squamous Carcinoma Cell Line Evaluated by an in vitro Invasion Model
Authors: Kawahara Ei , Okada Yasunori , Nakanishi Isao , Iwata Kazushi , Kojima Shinya , Kumagai Shigehiro , Yamamoto Etsuhide
Published: August 2005

In order to elucidate the factors contributory to the expression of invasiveness of oral squamous cell carcinoma, we conducted biochemical and morphological comparisons of well differentiated squamous carcinoma cell line OSC‐19 (oral squamous cell carcinoma) and undifferentiated carcinoma cell line KB, both cultured on 3T3 cell‐embedded collagen gel (in vitro invasion model). OSC‐19 cells invaded 3T3 cell‐embedded collagen gel, while KB cells and OSC‐19 cells on 3T3 cell‐free gel matrix were less invasive. Cultured OSC‐19 cells were characterized by lower proliferating activity, lower secretion of laminin and higher secretion of fibronectin than those of KB cells. Although the basement membrane with deposition of laminin and type IV collagen was formed, it was discontinuous at the invasion front. Gelatin zymography and western blotting showed matrix metalloproteinases (MMP), i.e., 72 kDa gelatinase (MMP‐2) and 92 kDa gelatinase (MMP‐9). Gelatinolytic activity was assayed, and was higher in OSC‐19 cells than in KB cells or OSC‐19 cells of the 3T3 cell‐free model. By immuno‐histochemical analysis, MMP‐2‐positive cells were found scattered in both cell lines without any preferential localization, and the positivity for MMP‐9 was localized in the invasion front of OSC‐19 cells. These results strongly suggest that the invasiveness of squamous cell carcinoma is well correlated with cell‐matrix adhesion by fibronectin and with focal elaboration of metalloproteinases, especially MMP‐9, which play a major role in degrading the extracellular matrix components.
Effects of Chemoendocrine Therapy on the Coagulation‐Fibrinolytic Systems in Patients with Advanced Breast Cancer
Authors:   Japan Advanced Breast Cancer Study Group,   Japan Clinical Oncology Group
Published: August 2005

In order to predict a hypercoagulable state in patients with advanced breast cancer receiving medical treatment, the effects of Chemoendocrine therapy on the coagulation‐flbrinolytic systems were investigated prospectively. The patients were randomly divided into two groups. The ACT group had 38 patients, who received 20 mg/m2 adriamycin (ADM) i.v. on days 1 and 8, 100 mg cyclophosphamide (CPA) p.o. on days 1–14, and 20 mg tamoxifen (TAM) p.o. daily. The ACM group had 44 patients, who received 20 mg/m2 ADM i.v. on days 1 and 8, 100 mg CPA p.o. on days 1–14 and 1200 mg medroxyprogesterone acetate (MPA) p.o. daily. The treatment was repeated every 28 days until there was evidence of progressive disease or until the full ADM dose (550 mg/m2) had been given. The following 9 hematologic parameters were measured every 4 weeks: alpha 2‐plasmin inhibitor plasmin complex (PIC), anti‐thrombin‐III (AT‐III), D‐dimer (Dd), fibrinogen (Fg), plasminogen (Pg), protein C (PC), thrombin‐antithrombin‐III complex (TAT‐III), tissue plasminogen activator (t‐PA), and factor × (FX). Compared to the ACT group, patients in the ACM group showed significantly higher values of AT‐III and PC, which exceeded the normal ranges. The levels of Pg, t‐PA and FX were significantly higher in the ACM group than in the ACT group, but were still within the normal ranges. The levels of TAT‐III, Dd and PIC decreased in the ACT group and were unchanged in the ACM group after the start of treatment. Fg remained unchanged in both groups after the start of treatment. One patient in the ACM group had thrombophlebitis of the lower extremities with high levels of TAT‐III, Dd and PIC and a decrease of Fg, but her condition returned to normal after reduction of the MPA dose. Although these data are not directly indicative of a hypercoagulable state in patients receiving Chemoendocrine therapy, changes in AT‐III, TAT‐III, Dd and PIC should be monitored carefully when this type of treatment is given.
Carboxyl‐terminal Heparin‐binding Fragments of Platelet Factor 4 Retain the Blocking Effect on the Receptor Binding of Basic Fibroblast Growth Factor
Authors: Sato Yasufumi , Waki Michinori , Ohno Motonori , Kuwano Michihiko , Sakata Toshiie
Published: August 2005

Platelet factor 4 (PF‐4) blocks the binding of basic fibroblast growth factor (bFGF) to its receptor. In the present study, we constructed carboxyl‐terminal fragments, which represent the heparin‐binding region of the PF‐4 molecule, and examined whether these synthetic peptides retain the blocking effects on the receptor binding of bFGF. Synthetic peptides inhibited the receptor binding of bFGF. Furthermore, they inhibited the migration and tube formation of bovine capillary endothelial cells in culture (these phenomena are dependent on endogenous bFGF).
The Murine cot Proto‐oncogene: Genome Structure and Tissue‐specific Expression
Authors: Ohara Reiko , Miyoshi Jun , Aoki Masahiro , Toyoshima Kumao
Published: August 2005

We cloned and analyzed the murine cot proto‐oncogene and examined its tissue‐specific expression in fetal, newborn and adult mice. Genomic cot DNA consists of eight exons, spanning more than 25 kb, and all intron‐exon borders are well conserved as compared to the human homolog. Analysis of the full‐length cot cDNA revealed that it contained an open reading frame of 1,401 nucleotides, like human cot proto‐oncogene. The sequence identity between murine and human cot gene is 84.4% at the nucleotide level and 93.9% at the deduced amino acid level. On northern blot analysis of poly (A)+ RNA, the cot message was detected at 2.9 kb in size. Expression of the cot gene was observed in many tissues from fetal to adult mice, though the level of expression was low in all tissues examined.
Enhancing Effects of Estrogens on Endometrial Carcinogenesis Initiated by N‐Methyl‐N‐nitrosourea in ICR Mice
Authors: Niwa Kenji , Murase Toshiko , Furui Tatsuro , Morishita Shigeo , Mori Hidehiro , Tanaka Takuji , Mori Hideki , Tamaya Teruhiko
Published: August 2005

The present study was undertaken to examine the effects of estrogens, such as estrone (E1), 17β‐estradiol (E2) and estriol (E3), on endometrial Carcinogenesis initiated by N‐methyl‐N‐nitrosourea (MNU) in mice. A total of 120 female ICR mice received MNU solution (1 mg/100 g body wt.) and normal saline at 10 weeks of age into their left and right uterine corpora, respectively. One week later, they were divided into four groups and treated as follows: Group 1 (30 mice) was given 25 ppm E1‐containing diet; Group 2 (30 mice) was fed 5 ppm E2‐containing diet; Group 3 (30 mice) was given 25 ppm E3‐containing diet; and Group 4 (30 mice) was fed the basal diet alone. At the termination of the experiment (Week 30), all surviving animals were autopsied and histopathological examinations revealed that endometrial adenocarcinomas had developed in all groups. The incidence of adenocarcinomas in the MNU‐treated uterine corpus in Group 1 (25 ppm E1‐feeding, 9/23, 39%) was significantly higher than that in Group 4 (basal diet, 3/26, 12%, P<0.05). Also, the incidences of adenocarcinomas in the MNU‐treated uterine corpus in Groups 2 (5 ppm E2‐feeding, 8/24, 33%) and 3 (25 ppm E3‐feeding, 7/26, 28%) were higher than in Group 4, but the difference was not statistically significant. Feeding of diet containing E1, E2 and E3 increased the incidences of the preneoplastic endometrial lesions (atypical, adenomatous or cystic glandular hyperplasia). In the uterine cervix, small numbers of squmous cell carcinomas, dysplasias or hyperplasias were occasionally found in all groups. These results indicate enhancing effects of the above three types of estrogens on the endometrial carcinogenesis induced by MNU in ICR mice.
Immunohistochemical Analysis of Cathepsin B Expression in Human Lung Adenocarcinoma: The Role in Cancer Progression
Authors: Ozeki Yuichi , Takishima Kunio , Takagi Keigo , Aida Shinsuke , Tamai Seiichi , Mamiya Gunji , Ogata Toshiro
Published: August 2005

Production of cathepsin B by tumor cells has been linked to metastatic potential in several experimental models. Sections of 95 primary lung adcnocarcinomas were examined for expression of cathepsin B using a standard avidin‐biotin immunohistochemical technique. Staining for cathepsin B was observed in 22.1% of all cases and 28.0% of those of the Clara cell type. In Clara cell adenocarcinomas, cathepsin B expression correlated with positive lymph node status, presence of distant metastases, and poor prognosis (P<0.05). However, no correlation with clinical outcome was observed in other cell types. Our data suggest that cathepsin B may be involved in invasion and metastasis in Clara cell lung adenocarcinoma.
Relationship between Development of Diarrhea and the Concentration of SN‐38, an Active Metabolite of CPT‐11, in the Intestine and the Blood Plasma of Athymic Mice Following Intraperitoneal Administration of CPT‐11
Authors: Araki Eiji , Ishikawa Masayuki , Iigo Masaaki , Koide Tsutomu , Itabashi Masayuki , Hoshi Akio
Published: August 2005

Severe diarrhea occurred during daily intraperitoneal administration of 7‐ethyl‐10‐[4‐(l‐piperidino)‐l‐piperidino]carbonyloxycamptothecin (CPT‐11) at a dose of 50 mg/kg in athymic mouse. Serial determination of CPT‐11 and 7‐ethyl‐10‐hydroxycamptothecin (SN‐38), with the use of an on‐line solid extraction HPLC system, demonstrated that much higher levels of the compounds are retained in the intestine and the blood plasma after five consecutive daily injections than after a single injection. Histologic examination of the gastrointestinal tract showed hemorrhagic colitis on day 7 and later after five consecutive daily injections of CPT‐11. The direct cause of diarrhea associated with CPT‐11 administration is considered to be enterocolitis caused by high levels of SN‐38 and/or CPT‐11 retained for a long period in the intestine.
Suppression of Rabbit VX‐2 Subcutaneous Tumor Growth by Gadolinium Neutron Capture Therapy
Authors: Akine Yasuyuki , Tokita Nobuhiko , Tokuuye Koichi , Satoh Michinao , Churei Hisahiko , Pechoux Cécile Le , Kobayashi Tooru , Kanda Keiji
Published: August 2005

VX‐2 tumors growing in hind legs of New Zealand White rabbits (n=4) were exposed to thermal neutrons for 40 min (2.1 × 1012 neutrons cm−2) while one of two hind leg tumors of each rabbit was infused continuously with meglumine gadopentetate through a branch of the left femoral artery. The contralateral (uninfused) tumors served as controls. Although no differential distribution of gadolinium was achieved between the tumor and its adjacent normal tissue, the gadolinium concentration in the infused tumor was approximately 5–6 fold higher than that in the contralateral tumor. Growth of gadolinium‐infused tumors was significantly inhibited compared to that of control tumors (P<0.05) between the 16th and 23rd days after treatment.
Expression of Amphiregulin, a Novel Gene of the Epidermal Growth Factor Family, in Human Gastric Carcinomas
Authors: Kitadai Yasuhiko , Yasui Wataru , Yokozaki Hiroshi , Kuniyasu Hiroki , Ayhan Ayse , Haruma Ken , Kajiyama Goro , Johnson Gibbes R. , Tahara Eiichi
Published: August 2005

The expression of mRNA for amphiregulin (AR), a novel gene of the epidermal growth factor family, was examined in 8 human gastric carcinoma cell lines and 32 gastric carcinoma tissues as well as corresponding normal mucosa. Of the 8 gastric carcinoma cell lines, 7 expressed 1.4 kb AR mRNA at various levels. The expression of AR mRNA by TMK‐1 and MKN‐28 cells was increased by treatment with epidermal growth factor or transforming growth factor α. In surgical cases, all the gastric carcinoma tissues and their adjacent normal mucosa expressed AR mRNA. Interestingly, 20 (62.5%) out of 32 tumors expressed AR mRNA at higher levels than their corresponding normal mucosas (tumor/normal ≥1.2). No obvious correlation was observed between the AR mRNA levels and the histological types or tumor staging of gastric carcinoma. Immunohistochemically, AR protein was localized to the cytoplasm and/or nucleus in tumor cells. These results suggest that AR produced by tumor cells may be involved in the pathogenesis and/or progression of human gastric carcinoma.