bluuebunny/crossref_metadata_2025 huggingface dataset:
A Simple and Useful Method for Simultaneous Screening of Elevated Levels of Expression of a Variety of Oncogenes in Malignant Cells
Authors: Nakamori Shoji , Mukai Hiroyuki , Higashi Takatsugu , Sasai Hitoshi , Miyoshi Jun , Takai Shin‐ichiro , Mori Takesada , Kakunaga Takeo
Published: August 2005

Abnormal expression of various oncogenes has been implicated in the development of many malignant tumors. Although RNA blotting methods have been used to measure abnormal expression, they involve the time‐consuming process of individually labeling the oncogene probes. To simplify this process we have attempted to develop a new method, termed simultaneous screening, which is based on the synthesis of radiolabeled cDNA corresponding to the mRNA population of malignant cells and on hybridization with various oncogene probes, immobilized on a membrane filter. This method circumvents the time‐consuming process of the prevailing RNA blotting methods and is also sensitive enough to detect accurately a five‐ to ten‐fold level of expression of rare mRNA (∼10 copies per cell). Overexpression of ten oncogenes was detected in a variety of malignant cells and mitogen‐stimulated cells with this method. These results suggest that our simultaneous screening method can be used to examine the overexpression of oncogenes.
Involvement of the Kinin‐generating Cascade in Enhanced Vascular Permeability in Tumor Tissue
Authors: Matsumura Yasuhiro , Kimura Masami , Yamamoto Tetsuro , Maeda Hiroshi
Published: August 2005

Enhanced vascular permeability in tumor tissue has profound pathological consequences in tumor biology. However, details of the mechanism involved are not clear. The present work on tumor vascular permeability has led to the following three findings, (i) Ascitic tumor fluid contained kinin (about 1‐40 ng/ml), which is known to enhance vascular permeability and induce pain in vivo, (ii) Kinin is generated via the kallikrein‐dependent cascade in the ascitic tumor fluid. By blocking this kinin‐generating cascade with Kunitz‐type soybean trypsin inhibitor the formation of ascites was suppressed, (iii) Blocking of kinin‐degrading enzymes (kininases I and II) by an appropriate kininase inhibitor (e.g., captopril) may result in increased permeability, leading to accumulation of the ascitic fluid. This phenomenon was verified by an about 1.2‐1.5 fold increase in leakage of 51Cr‐labeled bovine serum albumin into the ascites when kininase inhibitors had been administered orally 30 min before intravenous administration of the bovine serum albumin.
The Promoting Effects of Food Dyes, Erythrosine (Red 3) and Rose Bengal B (Red 105), on Thyroid Tumors in Partially Thyroidectomized N‐Bis(2‐hydroxypropyl)‐ nitrosamine‐treated Rats
Authors: Hiasa Yoshio , Ohshima Masato , Kitahori Yoshiteru , Konishi Noboru , Shimoyama Taketo , Sakaguchi Yasuhiro , Hashimoto Hiroyuki , Minami Shigenori , Kato Yuzuru
Published: August 2005

The effects of erythrosine (Red 3), rose bengal B (Red 105) and thyroidectomy on the development of thyroid tumor were examined in male Wistar rats treated with N‐bis(2‐hydroxypropyl)nitrosamine (DHPN). Red 3 and Red 105 were used at 4% in the basal diet and were administered for 19 weeks from week 2 to 20. Thyroidectomy was performed by resection of the left lobe at week 4. Single injection of DHPN was performed intraperitoneally at 280 mg per 100 g body weight at the beginning of the experiment. Red 3 and Red 105 significantly promoted the development of thyroid tumors in thyroidectomized rats given DHPN, but had no significant effect in non‐thyroidectomized rats. The incidence of thyroid tumors was 91% in rats with partial thyroidectomy, Red 3 and DHPN, 100% in rats with partial thyroidectomy, Red 105 and DHPN, and 64% in rats with partial thyroidectomy and DHPN. Serum TSH was 5.5±3.1 ng/ml in rats with partial thyroidectomy, Red 3 and DHPN, 2.1 ± 2.2 ng/ml in rats with partial thyroidectomy, Red 105 and DHPN, and 1.5±0.5 ng/ml in rats with partial thyroidectomy and DHPN.
Co‐carcinogenic Effect of Retinyl Acetate on Forestomach Carcinogenesis of Male F344 Rats Induced with Butylated Hydroxyanisole
Authors: Hasegawa Ryohei , Takahashi Michihito , Furukawa Fumio , Toyoda Kazuhiro , Sato Hidetaka , Hayashi Yuzo
Published: August 2005

The potential modifying effect of retinyl acetate (RA) on butylated hydroxyanisole (BHA)‐induced rat forestomach tumorigenesis was examined. Male F344 rats, 5 weeks of age, were maintained on diet containing 1% or 2% BHA by weight and simultaneously on drinking water supplemented with RA at various concentrations (w/v) for 52 weeks. In groups given 2% BHA, although marked hyperplastic changes of the forestomach epithelium were observed in all animals, co‐administration of 0.25% RA significantly (P<0.05) increased the incidence of forestomach tumors (squamous cell papilloma and carcinoma) to 60% (9/15, 2 rats with carcinoma) from 15% (3/20, one rat with carcinoma) in the group given RA‐free water. In rats given 1% BHA, RA co‐administered at a dose of 0.05, 0.1, 0.2 or 0.25% showed a dose‐dependent enhancing effect on the development of the BHA‐induced epithelial hyperplasia. Tumors, all papillomas, were induced in 3 rats (17%) with 0.25% RA and in one rat (10%) with 0.05% RA co‐administration. RA alone did not induce hyperplastic changes in the forestomach. These findings indicate that RA acted as a co‐carcinogen in the BHA forestomach carcinogenesis of the rat.
COAMPLIFICATION OF THE hst‐1 AND int‐2 GENES IN HUMAM CANCERS
Authors: Tsutsumi Masakazu , Sakamoto Hiromi , Yoshida Teruhiko , Kakizone Tadao , Koiso Kenkichi , Sugimura Takashi , Terada Masaaki
Published: August 2005

The hst‐1 gene, previously designated the hst gene, was identified as a transforming gene by transfection assays of genomic DNAs from various types of human cancers. We analyzed for alterations of the hst‐1 gene in 18 bladder cancers, 23 renal cell carcinomas and 5 esophageal cancers. Although rearrangement of the gene was not detected in any of these samples, amplification of the hst‐1 gene was found in 4 samples of tumors, including an invasive bladder cancer, both primary esophageal cancer and its lymph node metastasis, and kidney metastasis of an esophageal cancer. The same degree of amplification of the int‐2 gene, the product of which has significant homology with the hst‐1‐encoded protein, was also observed in all of these DNA samples with amplified hst‐1 gene. This result indicates close chromosomal localization of the two genes, which were amplified as one amplification unit.
Comparison of Lung Cancer Incidence Rates by Histological Type in High and Low Incidence Countries, with Reference to the Limited Role of Smoking
Authors: Hanai Aya , Benn Trevor , Fujimoto Isaburo , Muir Calum S.
Published: August 2005

To find a clue to lung cancer etiology in Japan, differences in the pattern of lung cancer histology and related time trends between Osaka, Japan, and the North West Region of England were investigated. Material comprised all incident lung cancer cases registered in both regional registries (14,521 in the Osaka Cancer Registry and 29,859 in the North West Regional Cancer Registry). (1) The age‐standardized incidence rate of lung cancer was higher in the North West Region than in Osaka (80.4 among males and 20.9 among females per 100,000 population in 1979–82 versus 32.1 and 9.2 respectively). (2) A higher proportion of adenocarcinoma was observed in Osaka (36.3% in males and 62.0% in females) than in the North West Region (12.3% and 18.9% respectively). (3) Using the relative frequencies of each histological type according to sex and age‐group, age‐standardized incidence rates were calculated for the main lung cancer histological types. It was shown that the incidence rates of adenocarcinoma were similar in the two areas (10.6 in males and 5.3 in females in Osaka versus 10.0 and 3.5 in the North West Region, respectively) while those of squamous cell and small cell carcinomas were much higher in the North West Region than in Osaka. (4) Time trends of incidence rates showed an increase only for adeno‐ and small cell carcinomas in Osaka. Slight increases were observed for adenocarcinoma in both sexes and for squamous cell carcinoma in females in the North West Region. (5) Considering cigarette consumption and the relative risks of smoking in the two areas, the possible existence of other risk factors for adenocarcinoma in both sexes in Japan, besides active smoking, was suggested.
High Susceptibility of an Analbuminemic Congenic Strain of Rats with an F344 Genetic Background to Induced Bladder Cancer and Its Possible Mechanism
Authors: Takahashi Masakazu , Shumiya Seigo , Maekawa Akihiko , Hayashi Yuzo , Nagase Sumi
Published: August 2005

The susceptibility of an analbuminemic congenic strain of rats (F344‐alb) originating from the F344 strain to N‐butyl‐N‐(4‐hydroxybutyl)nitrosamine (BBN) was examined. F344‐alb rats were found to be highly susceptible to induction of urinary bladder cancers. The incidences of bladder cancers in F344‐alb and F344 rats were 94% (15/16) and 31% (5/16) in males and 100% (16/16) and 19% (3/16) in females. The bladder weights of these rats, including tumors, were 307±294 mg, 123±26 mg, 183±80 mg and 93±11 mg, respectively. Administration of 0.05%, 0.1% and 0.3% BBN in the drinking water for 2 weeks resulted in greater increases in the bladder content of N‐butyl‐N‐(3‐carboxypropyl)nitrosamine in F344‐alb rats than in F344 rats. This increase was prevented by the presence of rat albumin.
Nucleotide Sequence and Chromosomal Mapping of the Human c‐yes‐2 Gene
Authors: Semba Kentaro , Nishizawa Makoto , Satoh Hitoshi , Fukushige Shin‐ichi , Yoshida Michihiro C. , Sasaki Motomichi , Marsusbra Ken‐ichi , Yamamoto Tadashi , Toyoshima Kumao
Published: August 2005

We molecularly characterized the second gene, c‐yes‐2, of two copies of yes‐related genes which we previously found to contain in the human genome. First, nucleotide sequence analysis revealed that the c‐yes‐2 gene is a pseudogene of the c‐yes‐1 gene. Second, by using two independent methods, hybridization of both DNAs from sorted chromosomes and metaphase spreads with c‐yes‐2 DNA, we assigned the c‐yes‐2 gene to chromosome 22q11.2. This chromosomal localization is inconsistent with that given in our previous report. The failure of proper mapping in our experiment might have been caused by instability of hybrid cell clones.
Resistance to Serum‐induced Terminal Differentiation in Normal Human Tracheobronchial Epithelial Cells after in vivo Exposure to 7,12‐Dimethylbenz[a]anthracene
Authors: Baba Masayuki , Obara Takeshi , Bonfil R. Daniel , Yamaguchi Yutaka , Trump Benjamin F. , Resau James , Klein‐Szanto Andres J. P.
Published: August 2005

Normal human tracheobronchial epithelial cells (NHTBECs) from nine donors were used to repopulate de‐epithelialized rat tracheas. After transplantation into nude mice and treatment with 7,12‐dimethylbenz[a]anthracene (DMBA), the transplants were removed at 3, 4, 5 and 6 months. Epithelial cells from DMBA‐treated tracheas were subculturable. Epithelial cells from most untreated tracheas were not subculturable. After treatment with 0.5,1, 2, 4, 6 and 8% serum, cells exhibited increased subculturability after in vivo treatment with DMBA, did not terminally differentiate and were still proliferating even in medium containing 8% serum. Karyotypes from these cells showed considerable aneuploidy. Although these cells did not survive for more than 10 subcultures (42 weeks), this was considerably longer than the survival of control cells. Because of their longer survival, resistance to serum‐induced terminal differentiation and chromosome alterations, they were considered to be phenotypically altered or partially transformed cells produced by in vivo treatment of human cells with a chemical carcinogen.
Invasion and Metastasis of SY86B Human Gastric Carcinoma Cells in Nude Mice
Authors: Li Hong , Zhang Yin‐Chang , Tsuchihashi Yasunari
Published: August 2005

A moderately differentiated tubular adenocarcinoma of human stomach, named SY86B, was successfully transplanted subcutaneously to nude mice of different genetic backgrounds (BALB/CA/PBI‐nu, C57BL/6J.615/PBI‐nu and ICR‐BALB/CA/PBI‐nu). The tumor has been passaged for 13 generations and the transplantability was 100%. The SY86B cells retained the capacity of invasive and metastatic growth in the nude mice and showed a high rate of metastasis to the regional lymph nodes and to such distant organs as the lungs, liver and pancreas. The overall rate of metastasis was 77.7%. The species of the nude mice, their age and sex apparently did not significantly affect the occurrence of metastasis. Tumor‐bearing time and the aggressive character of the tumor cells themselves appeared important for the genesis of metastasis. This experimental model can provide a new approach to basic and clinical studies of cancer metastasis.
Strain Differences in Susceptibility to 2‐Acetylaminofluorene and Phenobarbital Promotion of Rat Hepatocarcinogenesis in a Medium‐term Assay System: Quantitation of Glutathione S‐Transferase P‐positive Foci Development
Authors: Asamoto Makoto , Tsuda Hiroyuki , Kagawa Masataka , de Camargo Joao Lauro V. , Ito Nobuyuki , Nagase Sumi
Published: August 2005

Strain differences in susceptibility to promotion by the liver carcinogens 2‐acetylaminofluorene (2‐AAF) and phenobarbital (PB) were examined in the medium‐term bioassay system initially developed in our laboratory using male F344 rats as the test animal and glutathione S‐transferase placental form (GST‐P)‐positive foci as the lesion end‐point. Numbers and areas per cm2 of induced GST‐P‐positive hepatocellular foci were compared in LEW, F344, NAR, SD, WBN, SHR, Wistar and ODS rats initiated with diethylnitrosamine (DEN) and subjected to partial hepatectomy during subsequent administration of 2‐AAF or PB. LEW, SD, WBN, and F344 rats were most susceptible to hepatopromotion by both compounds, with a hundred fold increase in lesion area being observed for 2‐AAF in the LEW case. NAR and SHR strains demonstrated an intermediate response, while Wistar and, in particular, the related ODS rats demonstrated very low susceptibilities. The obvious strain differences could be expressed in terms of comparative indices of promoting effects of 2‐AAF and PB as well as DEN itself regarding each of the 8 strains tested. The use of F344 rats for the bioassay model was validated by the relatively high sensitivity to both DEN and 2‐AAF initiation as well as second‐stage promotion stimulus exhibited.
Inhibition by Dietary Benzylselenocyanate of Hepatocarcinogenesis Induced by Azoxymethane in Fischer 344 Rats1
Authors: Sugie Shigeyuki , Reddy Bandaru S. , El‐Bayoumy Karam , Tanaka Takuji
Published: August 2005

The effect of dietary benzylselenocyanate (BSC), a novel organoselenium compound and its sulfur analog, benzylthiocyanate (BTC), on hepatocarcinogenesis induced by azoxymethane (AOM) was investigated in male F344 rats. Eighty‐one weanling rats were divided into 3 groups and were raised on a semipurificd diet (control diet). Starting from 5 weeks of age, groups of animals consuming the control diet were fed one of the experimental diets containing 25 ppm BSC or BTC. An additional group was continued on the control diet. At 7 weeks of age, animals were given weekly sc injections of AOM (15 mg/kg body weight once weekly for 2 weeks). One week after the second AOM injection, those groups receiving BSC and BTC diets were transferred to the control diet and continued on this diet until termination of the experiment at 34 weeks after the last AOM injection. For quantitative analysis of enzyme‐altered liver cell foci, glutathione S‐transferase placental form was stained by an immunohistochemical technique. The results indicate that the incidence and the density of the enzyme‐altered foci were significantly lower in AOM‐treated rats fed the diet containing 25 ppm BSC (foci incidence 56%, foci density 2.43/cm2) than in AOM‐treated animals fed the control diet (foci incidence 92%, foci density 4.79/cm2). The incidence of small altered foci was significantly inhibited in rats fed the BTC diet (35%) as compared to those fed the control diet (68%), but the degree of inhibition was more pronounced in animals fed the BSC diet than in those fed the BTC diet.
Translocation t(12;16)(q13;pll) in Myxoid Liposarcoma of a Child and Implica of the Human int‐1 Gene in Tumorigenesis
Authors: Fujii Yuji , Matui Yuka , Nakagawa Yuichi , Hongo Teruaki , Igarashi Yoshio , Yamada Masao , Nakagome Yasuo , Tobayama Shigeo
Published: August 2005

Cytogenetic and gene analyses were performed in a child with myxoid liposarcoma (MLS). A reciprocal chromosome translocation t(12;16)(q13:pll) was found in the tumor cells. This result, combined with the previous reports of a similar translocation in adult MLS strongly suggests that this translocation may be a characteristic cytogenetic marker in MLS. The human int‐1 gene has been reported to be located close to the 12q1 breakpoint associated with MLS. Therefore, we examined the rearrangement of the human int‐1 gene by Southern blotting analysis. When genomic DNAs from the tumor cells were digested with KpnI, EcoRI and BamHI, no difference was seen compared to peripheral blood leukocytes (PBL) DNAs from a normal individual. However, with HindIII digestion there appeared a 3.1 kb fragment in tumor cell DNA as compared to a 2.8 kb fragment in DNAs prepared from normal PBL and the patient's PBL. These findings suggest that the int‐1 gene may be implicated in tnmorigenesis of MLS with t(12;16)(q13;pll).
Contrasting Actions of Estradiol on the Growth of Human Gastric Cancer Xenografts in Nude Mice
Authors: Tokunaga Akira , Onda Masahiko , Kiyama Teruo , Nishi Keigo , Mizutani Takashi , Yoshiyuki Toshiro , Shimizu Yasuhito , Matsukura Norio , Tanaka Noritake , Asano Goro
Published: August 2005

The effects of estradiol on the growth of six human gastric xenografts in nude mice were studied and diverse effects were found, including one case of stimulation, two of inhibition and three of unchanged condition. Neither the histological features of the original tumor nor the estrogen‐binding capacity seemed to be related to the response to estradiol. It is concluded that the growth of human gastric cancer can be modulated by estradiol.
Lymphokine‐activated Killer Induction and Its Regulation by Macrophages in Malignant Pleural Effusions
Authors: Yanagawa Hiroaki , Sone Saburo , Nii Akihiko , Fukuta Katsuyuki , Nakanishi Mie , Maeda Ken‐ichi , Honda Mitsuo , Ogura Takeshi
Published: August 2005

Mononuclear cells (MNC) from pleural effusions and peripheral blood of 18 patients with primary lung cancer with malignant pleural effusion were studied. Pleural and blood MNC generated lymphokine‐activated killer (LAK) activity similarly when cultured for 4 days with an optimal concentration of interleukin 2 (IL‐2). Highly purified lymphocytes (>98%) and monocyte‐macrophages (>90%) were isolated by discontinuous Percoll gradient centrifugation from pleural and blood MNC. Pleural macrophages, as well as blood monocytes, showed significant augmenting effects on in vitro LAK cell induction from pleural and blood lymphocytes by IL‐2. During daily intrapleural administration of IL‐2, significant induction of LAK activity in vivo was observed after 3 days, but then this LAK activity in pleural MNC decreased almost to zero by day 15. Daily injections of IL‐2 resulted in reduction in the up‐regulation of LAK induction by pleural macrophages and also in increase in the levels of soluble IL‐2 receptors in pleural effusions. These findings indicate that in vivo LAK induction of lymphocytes in malignant effusions by IL‐2 may be regulated by macrophages in the effusions.
Effects of the in vivo Administration of Recombinant Human Granulocyte Colony‐stimulating Factor Following Cytotoxic Chemotherapy on Granulocytic Precursors in Patients with Malignant Lymphoma1
Authors: Ema Hideo , Suda Toshio , Sakamoto Shinobu , Tomonaga Takafumi , Tsunoda Jun‐ichi , Muroi Kazuo , Komatsu Norio , Miwa Akiyoshi , Ohsaka Akimichi , Yoshida Minoru , Motoyoshi Kazuo , Takaku Fumimaro , Miura Yasusada
Published: August 2005

We examined the effects of the in vivo administration of recombinant granulocytc colony‐stimulating factor (rhG‐CSF) on granulocytic precursors in the bone marrow of 4 patients with malignant lymphoma who received chemotherapy. Patients were treated with rhG‐CSF at doses of 100–800 μg/ m2/day intravenously for 14 days only in the first course of chemotherapy (G‐CSF course) followed by the second course of chemotherapy without rhG‐CSF which was used as a control course. In the G‐CSF course, white blood cell counts (WBCs) demonstrated a biphasic response consisting of a first peak observed within a few days after the initiation of rhG‐CSF administration, and a second peak observed on the last day of rhG‐CSF injection or the day after. In the second peak, the incidence of granulocyte‐macrophage colony‐forming units (CFU‐GM) in mononucleated bone marrow cells did not change significantly after treatment with rhG‐CSF as compared with a control. However, since the number of nucleated cells in the bone marrow increased, the absolute number of CFU‐GM in the bone marrow increased. The number of mature and immature granulocytes in the bone marrow increased. These findings suggest that G‐CSF stimulates the proliferation and differentiation of granulocytic precursors in the bone marrow in granulocytopenic patients who received cytotoxic drugs and causes mature granulocytes to be released from the bone marrow.
Positive Foci of Glutathione S‐Transferase Placental Form in the Liver of Rats Given Furfural by Oral Administration
Authors: Shimizu Akio , Nakamura Yoshiyasu , Harada Masaoki , Ono Tetsuo , Sato Kiyomi , Inoue Tohru , Kanisawa Masayoshi
Published: August 2005

We observed GST‐P‐positive liver foci in rats during the course of developing liver cirrhosis by oral administration of furfural, an organic solvent. Male Wistar rats were given furfural‐containing diet (20–30 rag/kg diet) for 15–150 days, and killed 14 days after terminating furfural feeding. Immuno‐histochemical investigation of GST‐P‐positive liver foci which appeared in rats fed furfural for more than 30 days revealed an increase in number and size of the foci in proportion to the duration of furfural administration. Since furfural is known not to be carcinogenic in rats, this finding will be helpful to understand the enhancing effect of furfural‐induced cirrhosis on chemical hepatocarcino‐genesis.
Rearranged Epstein‐Barr Virus Genomes and Clonal Origin in Nasopharyngeal Carcinoma
Authors: Shimakage Misuzu , Chatani Masashi , Ikegami Nobuko , Hirai Kanji
Published: August 2005

Epstein‐Barr virus (EBV) is known to be associated with two malignant diseases, nasopharyngeal carcinoma (NPC) and endemic Burkitt's lymphoma. In this study, the genomes of EBV in biopsy specimens from 4 NFC patients in Japan were analyzed using Southern blot hybridization. The NPC tissues of all examined cases contained rearranged EBV genomes whose BamHI H fragments were larger than those of prototype EBV genomes. One of them had a BamHI fragment containing contiguous sequences of BamHI Y and H. A single‐sized EBV DNA terminus was observed in these NPC tissues, implying the evolution of the carcinoma from a single EBV‐infected cell.
Dose‐Response Carcinogenicity in Rats on Low‐dose Levels of N‐Ethyl‐N‐nitrosourethane
Authors: Maekawa Akihiko , Onodera Hiroshi , Matsushima Yuko , Nagaoka Takaharu , Todate Asahi , Shibutani Makoto , Kodama Yukio , Hayashi Yuzo
Published: August 2005

A dose‐response study on the carcinogenicity of N‐ethyl‐N‐nitrosourethane (ENUR) was undertaken to examine its effect at low doses. Six‐week‐old female F344 rats were divided into 5 groups, each consisting of 40 animals. ENUR was dissolved in distilled water at dose levels of 0 (control), 0.15, 0.6, 2.5 and 10 ppm, and rats were given these solutions ad libitum for 2 years. Significant increase of the total tumor incidences and shortening of the mean survival times were observed in groups given 2.5 and 10 ppm ENUR. In groups given 0.6 ppm or more ENUR, digestive tract tumors were induced dose‐dependently. They were restricted to the upper digestive tract from the oral cavity to the forestomach, and were histologically squamous cell papillomas or carcinomas. Dose‐related differences in the location and incidence of these tumors were found. The virtually safe doses (VSDs) calculated by using the Weibull, Logit and Probit models were 0.365 × 10‐2, 0.110 × 10‐1 and 0.779 × 10‐1 ppm, respectively. The VSDs estimated in the present study are discussed in comparison with those of other carcinogens.
A Case of Leiomyosarcoma Associated with Humoral Hypercalcemia of Malignancy: Demonstration of Biological and Immunological Activities of Parathyroid Hormone‐related Protein in the Tumor Extract
Authors: Nagata Naokazu , Takeda Jyun , Kugai Nobuo , Kimoto Hiroyuki , Tomimatsu Souichi , Takatani Osamu , Suzuki Kazuo , Fuse Yusuke , Tsuchihashi Takayuki , Yamaguchi Ken , Abe Kaoru
Published: August 2005

Hypercalcemia occurred in a patient with leiomyosarcoma when multiple lung metastases developed. Despite normal plasma parathyroid hormone (PTH) levels and low 1,25‐dihydroxyvitamin D, this hypercalcemic patient had a marked hypercakiuria and phosphatnria associated with an increased excretion of nephrogenous cyclic AMP (NcAMP). Administration of cisplatin ameliorated both the hypercalcemia and hypercalciuria without any reduction in tumor size or NcAMP excretion. Terminally, acute pancreatitis occurred producing a profound hypocalcemia. In the extract of tumor tissue obtained post mortem, bioactivity stimulating the generation of cyclic AMP in osteogenic cells was demonstrated along with the immunoreactive PTH‐related protein (PTH‐rP). This is the first report of a solid non‐epithelial malignancy producing PTH‐rP and associated with humoral hypercalcemia of malignancy. The hypercalcemia in this case caused acute pancreatitis, which led to a profound hypocalcemia
Inhibition of Human Immunodeficiency Virus Infection of Human Lymphocytes by Gangliosides
Authors: Nakakuma Hideki , Kawaguchi Tatsuya , Koito Atsushi , Hattori Toshio , Kagimoto Tadashi , Takatsuki Kiyoshi
Published: August 2005

As the first step in human immunodeficiency virus (HIV) infection, HIV binds to CD4 molecules on the surface of human T lymphocytes. Expression of CD4 by the cells is remarkably modulated by exogenously added gangliosides, which are normal components of the surface of animal cells. We report here that these physiological molecules also clearly inhibited HIV infection of lymphocytes in vitro in a dose‐dependent manner through the selective modulation of CD4 from the cell surface. This raises the possibility of in vivo application of gangliosides as a new strategy for treating acquired immunodeficiency syndrome.
Diversity of Cellular Molecules in Human Cells Detected by Monoclonal Antibodies Reactive with c‐myc Proteins Produced in Escherichia coli
Authors: Naoe Tomoki , Nozaki Naohito , Yamada Kazumasa , Okazaki Tuneko , Nakayama Eiichi , Kurosawa Yoshikazu , Shiku Hiroshi
Published: August 2005

Six clones of monoclonal antibodies, MYC‐1 to ‐6, were prepared by using two kinds of truncated c‐myc proteins, p23 and p42, produced in Escherichia coli as immunogens. Analysis with enzyme‐linked immunosorbent assays and immunoblotting assays with peptides produced in Escherichia coli showed that 5 clones of monoclonal antibodies, MYC‐1 to ‐4 and ‐6, were reactive with c‐myc protein encoded by exon 2. The remaining one clone, MYC‐5, was reactive with the portion of c‐myc protein encoded by exon 3. All monoclonal antibodies were also reactive with phosphorylated c‐myc protein produced by insect cells infected by the baculovirus expression vector with the human c‐myc gene. With immunoblotting assays using cellular lysates, MYC‐1 and ‐3 detected bands at the levels of 58 kDa and 60 kDa, MYC‐5 detected a band at 56 kDa and MYC‐6 detected bands at 68 kDa and 75 kDa. All of these bands were detectable in nuclear extracts of HL‐60 and Colo320, both of which have amplified c‐myc genes, and also the extract of RmycYl which is the c‐myc gene transfectant into 3Y1 rat cells. None of them was detectable in peripheral blood mononuclear cells and 3Y1, both of which lacked activated c‐myc genes. This indicates that these nuclear proteins are either c‐myc gene products or molecules closely related to the c‐myc gene. The remaining two clones, MYC‐2 and ‐4, detected a band at the level of 85 kDa in cytoplasmic extracts of all the above‐mentioned cells independent of the presence of the c‐myc gene. This suggests that 85 kDa protein might be irrelevant to the c‐myc gene. The 56 kDa protein was detectable by MYC‐5 in phytohemagglutinin‐stimulated peripheral blood mononuclear cells as well as leukemic cells of some patients.
Human Carcinogens So Far Identified
Authors: Tomatis Lorenzo , Aitio Antero , Wilbourn Julian , Shuker Linda
Published: August 2005

The massive exploitation of natural resources, of which tobacco and asbestos are two conspicuous, though very different examples, and the synthesis of industrial chemicals have generated new hazards and new carcinogens which have been added to older ones. The majority of the over 50 agents that have been firmly identified so far as being human carcinogens belong to the relatively new hazards, that is environmental chemicals or chemical mixtures to which humans have been exposed only during the last century and a half. They are of more importance for cancer occurring in men than in women, and there is no evidence so far that they are related to cancers occurring at some of the most common target sites in either sex. It would be mistaken to believe that complete cancer prevention could be achieved solely by controlling these new, or relatively new, carcinogenic agents, but it would be similarly wrong to deny the importance of trying to control them and of continuing to do so. The experimental approach for the identification of carcinogens has an irreplaceable role to play in preventing the dispersal into our environment of new hazards and in identifying among the chemicals already in use, those that are carcinogenic. That a closer integration between the epidemiological and the experimental approaches may succeed in substantially reducing the size of the unknown region within the spectrum of cancer‐causing factors, is today's hope that awaits confirmation. At the same time, advances in the understanding of the mechanisms underlying the different steps of the process leading to the clinical manifestation of cancer may help in the uncovering of agents and risk factors that the approaches used, at least in the way they have been used until now, may not have been apt to identify.
In vitro Invasion of Endothelial Cell Monolayer by Rat Ascites Hepatoma Cells
Authors: Ohigashi Hiroaki , Shinkai Kiyoko , Mukai Mutsuko , Ishikawa Osamu , Imaoka Shingi , Iwanaga Takeshi , Akedo Hitoshi
Published: August 2005

To study the tissue preference of invasion, we developed an assay system for the invasion of endothelial cells as a modification of the previously established assay of tumor cell invasion of meso‐thelial cells. Rat ascites hepatoma cells (AH 130) that had been seeded on a monolayer of cultured endothelial cells penetrated and formed tumor cell colonies under the monolayer. The penetration was time‐dependent and the number of penetrated tumor cells and colonies was proportional to the number of tumor cells seeded. Comparison of the in vitro tumor cell invasion of endothelial cell monolayer with that of cultured mesothelial cell layer showed that a clone from the tumor cells (CI‐30) which was highly penetrative into the mesothelial cell layer had only a limited ability to penetrate the endothelial cell layer.
In situ Freezing of the Rat Urinary Bladder: DNA Adduct Formation in the Bladder Epithelium Demonstrated by 32P‐Postlabeling Assay
Authors: Hasegawa Ryohei , Yamashita Katsumi , Morimoto Kazushige , Furukawa Fumio , Toyoda Kazuhiro , Shimoji Naoshi , Takahashi Michihito , Hayashi Yuzo
Published: August 2005

In situ freezing of the urinary bladder has been demonstrated to exert tumor‐initiating potential in two‐stage urinary bladder carcinogenesis in the rat. In the present experiment, DNA modification was examined after in situ freezing of the whole urinary bladder performed by pinching with frozen forceps at —15°C or —30°C for 2 s. The 32P‐postlabeling analysis revealed at least 2 DNA adducts in the epithelial cells of the urinary bladder collected 3 days after freezing. Single‐strand breaks of DNA were also found by means of the alkaline elution assay in the bladder epithelium collected 10 min after freezing. Thus, the previously demonstrated tumor‐initiating activity of in situ freezing in urinary bladder carcinogenesis was revealed to be associated with substantial DNA damage and adduct formation.
Establishment and Characterization of a Small Round Cell Sarcoma Cell Line, SCCH‐196, with t(11;22)(q24;q12)
Authors: Homma Chieko , Kaneko Yasuhiko , Sekine Ki‐ichi , Hara Shin‐ichi , Hata Jun‐ichi , Sakurai Masaharu
Published: August 2005

A cell line designated SCCH‐196 was established from an extraskeletal small round cell sarcoma developed in a 16‐year‐old Japanese girl. The cells grew as a monolayer, and have been continuously propagated by serial subcultures during the past 26 months. Cells from the primary tumor and those from the SCCH‐196 cell line at passage 10 both showed the same karyotype, 51, XX, + 8, + 20, + 21, t(11;22)(q24;q12), + i(1q), + i(1q). Histologically the primary tumor was difficult to classify as either Ewing's sarcoma (ES) or peripheral neuroepithelioma (NE). Neuron‐specific enolase‐positive cells in the primary tumor and the occurrence in the upper extremity were in favor of NE, while positive reaction of SCCH‐196 cells to an ES‐speciflc monoclonal antibody 5C11 suggested a diagnosis of ES. The SCCH‐196 cell line may be useful for basic studies on differentiation of neuroectodermal tumors, and for future cloning of still unidentified genes which may be located at the breakpoints of the 11;22 translocation.
Inhibitory Effect of Chitin Heparinoids on the Lung Metastasis of B16‐BL6 Melanoma
Authors: Murata Jun , Saiki Ikuo , Nishimura Shin‐ichiro , Nishi Norio , Tokura Seiichi , Azuma Ichiro
Published: August 2005

Structure‐function studies for the antimetastatic activity of chemically modified chitin heparinoids composed of N‐acetyl glucosamine units were performed in an experimental lung metastasis model. 6‐O‐Sulfatcd chitin (S‐chitin) significantly inhibited the lung tumor colonization in proportion to the degree of sulfation. However, 6‐O‐ and N‐sulfated but partially N‐deacetylated chitin (S‐chitosan), and 6‐O‐carboxymethylated chitin (CM‐chitin) had no effect. 6‐O‐Sulfated CM‐chitin (SCM‐chitin), which exhibited fairly low levels of anticoagulant activity, was also more effective than intact heparin. Furthermore, SCM‐chitin with a high degree of sulfation (SCM‐chitin III) caused a marked decrease of the number of lung tumor colonies in the spontaneous lung metastasis model. These results strongly suggest that 6‐O‐sulfate and N‐acetyl groups in the glucosamine unit were required for the antimetastatic effect of chitin heparinoids as well as heparin, and SCM‐chitin III may be of therapeutic benefit for the prevention of tumor metastasis.
Altered Expression of a Third Actin Accompanying Malignant Progression in Mouse B16 Melanoma Cells
Authors: Taniguchi Shun'ichiro , Sadano Hiroyuki , Kakunaga Takeo , Baba Tsuneo
Published: August 2005

The expression of actin was examined and compared in several mouse B16 melanoma cell lines with different metastatic ability, by the use of two‐dimensional gel electrophoresis or horizontal isoelectric focusing. In the mouse B16 melanoma cell lines, the expression of newly found Ax actin (Mr = 43,000, pl = 5.2) decreased with the increase in in vitro and in vivo selection cycles (F number) for high‐metastatic cells. On the contrary, the metastatic ability of each mouse cell line, assessed by lung colony‐forming ability following iv administration, increased with increase in the F number. The half life of Ax actin was much the same as that of β‐and γ‐actin and the different expressions of Ax actin between the low‐ (F=l) and high‐metastatic (F=10) cell lines were attributed to differences in the rate of synthesis but not in the decay rate of Ax actin. The Ax actin was incorporated into the cytoskeletal fraction with the same efficiency as β‐and γ‐actin. The invasiveness of the cells, assessed in vitro using matrigel, was increased with the decrease in Ax expression. The actin stress fibers, observed staining with rhodamine‐conjugated phalloidin, were organized better in a low‐metastatic cell line (F=l) than in a high‐metastatic one (F = 10). These results suggest to us that depression of Ax actin is involved in disorganization of the cytoskeletal system, the cellular flexibility and motility are enhanced and there is a consequent increase in the invasiveness and metastatic potential.
Accumulation of Abnormally High Ploid Nuclei in the Liver of LEC Rats Developing Spontaneous Hepatitis
Authors: Fujimoto Yoshinori , Oyamada Masahito , Hattori Atsuo , Takahashi Hidetoshi , Sawaki Masakuni , Dempo Kimimaro , Mori Michio , Nagao Minako
Published: August 2005

Enlarged hepatocytes with huge nuclei were found in LEC rats with hereditary hepatitis. Flow cytometric analysis of the DNA content of nuclei from jaundiced LEC rats revealed the presence of very high polyploids, such as 32n and 64n. At the age of 12 weeks, before the onset of hepatitis, 8n polyploid nuclei were more frequent in LEC rats than in LEA rats, a sibling line of LEC rats. Binucleated hepatocytes were also more frequent in LEC rats than in LEA rats at week 4. Bi‐, tri‐ and tetra‐nucleated cells whose nuclei were sometimes different in size were observed when jaundice became manifest. The number of proliferating liver cells, determined by pulse labeling with 5‐bromo‐ 2′‐deoxyuridine (BrdU), was higher in LEC rats than in LEA rats at 2, 4, 8, 12 and 14 weeks, with a maximum at week 4. A remarkable increase of BrdU uptake was observed at week 16, when jaundice developed. The possible involvement of abnormal cytokinesis and kariokinesis in the manifestation of hepatitis was suggested.
Palatal Mucosal Changes among Reverse Smokers in an Indian Village
Authors: Gavarasana Satyanarayana , Susarla Maha Deva Sastri
Published: August 2005

The smoking habits of 324 villagers of Uppada, East Godavari District, A.P., India, and their effect on the palatal mucosa leading to cancer, were studied. The frequency of reverse smoking (i.e., smoking with the lighted end inside the mouth) was 6.23 times higher in females than in males. The frequency of preleukoplakia was 2.26 times higher, that of leukoplakia was 13.84 times higher, and that of stomatitis nicotina was 7.13 times higher in reverse smokers than in regular smokers. These frequencies are lower compared to earlier studies done in the 60's and 70's in the districts of Visakhapatnam and Srikakulam.
Overexpression and Amplification of the c‐myc Gene in Mouse Tumors Induced by Chemicals and Radiations
Authors: Niwa Ohtsura , Enoki Yoshitaka , Yokoro Kenjiro
Published: August 2005

We examined expression of the c‐myc gene by the dot blot hybridization of total cellular RNA from mouse primary tumors induced by chemicals and radiations. Expression of the c‐myc gene was found to be elevated in 69 cases among 177 independently induced tumors of 12 different types. DNA from tumors overexpressing the myc gene was analyzed by Southern blotting. No case of rearrangement was detected. However, amplification of the c‐myc gene was found in 7 cases of primary sarcomas. These included 4 cases out of 24 methylcholanthrene‐induced sarcomas and 3 cases out of 7 α‐tocopherol‐indnced sarcomas. We also analyzed 8 cases of sarcomas induced by radiations, but could not find changes in the gene structure of the c‐myc gene. Thus, our data indicate tumor type specificity and agent specificity of c‐myc gene amplification.
Proliferative Cell Index in Endometrial Adenocarcinoma of Different Nuclear Grades
Authors: Mushika Masafumi , Shibata Kanemitsu , Miwa Tadashi , Suzuoki Yozo , Kaneda Tsuguhiro
Published: August 2005

Proliferative cell indices (PCI) in 20 cases of endometrial adenocarcinoma were obtained by staining DNA polymerase α. The PCI ranged from 11.1 to 42.1, averaging 24.7±8.7. Four cases of stage III all exhibited fairly large PCI (30.4–32.9). In contrast, in 16 cases of stage I the values were spread over a wide range. In 13 cases with histological grade (HG) 1 of stage I, larger PCI were obtained in the nuclear grade (NG) 2 group; the mean PCI values of HG 1‐NG 1 and HG 1‐NG 2 were 16.5 ±4.6 and 25.6±5.2, respectively. Because of the good correlation between PCI and HG or NG, PCI may be useful as an additional prognostic factor in endometrial adenocarcinoma, especially in stage I cases.
Pleural Lavage Cytology Immediately after Thoracotomy as a Prognostic Factor for Patients with Lung Cancer
Authors: Kondo Haruhiko , Naruke Tsuguo , Tsuchiya Ryousuke , Goya Tomoyuki , Suemasu Keiichi , Yamagishi Kimie , Kishi Kiyozo , Noguchi Masayuki
Published: August 2005

Pleural lavage cytology was examined in 230 lung cancer patients just after opening the chest. There were 16 cases (7.0%) of positive pleural lavage cytology, and the results of pleural lavage cytology were related to the presence of pleural involvement by cancer, microscopical pleural dissemination and lymphatic permeation of the cancer cells. If the cancer involves the pleura or lymphatics of the submesothelial layer, being covered with visceral mesothelium, positive cytology may still be obtained. Pleural lavage cytology at opening of the chest seems to be available as a premonitory indicator for exfoliation and dissemination into the pleural cavity or subpleural lymphatic extension of cancer cells, and it was suggested that positive pleural lavage cytology has an influence on postoperative survival.
Cell Surface Antigens of Radiation Leukemia Virus‐induced BALB/c Leukemias Defined by Syngeneic Cytotoxic T Lymphocytes
Authors: Kaneko Yukio , Oettgen Herbert F. , Obata Yuichi , Nakayama Eiichi
Published: August 2005

Two cell surface antigens of mouse leukemias were defined by BALB/c cytotoxic T lymphocytes (CTL) generated against syngeneic radiation leukemia virus(RadLV)‐induced leukemia, BALBRV1 or BALBRVD. Hyperimmunization of BALB/c mice with irradiated leukemias followed by in vitro sensitization of primed spleen cells resulted in the generation of CTL with high killing activity. The specificity of CTL was examined by direct cytotoxicity assays and competitive inhibition assays. A shared cell surface antigen, designated as BALBRV1 antigen, was detected by BALB/c anti‐BALBRV1 CTL. BALBRV1 antigen was expressed not only on RadLV‐induced BALB/c leukemias except for BALBRVD, but also on spontaneous or X‐ray‐induced BALB/c leukemias, chemically‐induced leukemias with the H‐2d haplotype and some chemically‐induced BALB/c sarcomas. In contrast, a unique cell surface antigen, designated as BALBRVD antigen, was detected by BALB/c anti‐BALBRVD CTL. BALBRVD antigen was expressed only on BALBRVD, but not on thirty‐nine normal lymphoid or tumor cells. These two antigens could be distinguished from those previously defined on Friend, Moloney, Rauscher or Gross murine leukemia virus (MuLV) leukemias, or MuLV‐related antigens. Both cytotoxic responses were blocked by antisera against H‐2Kd, but not H‐2Dd. The relationship of BALBRV1 antigen and BALBRVD antigen to endogenous MuLV is discussed with regard to the antigenic distribution on tumor cell lines.
Endothelin Potentiates Growth Factor‐stimulated DNA Synthesis in Swiss 3T3 Cells
Authors: Kusuhara Masatoshi , Yamaguchi Ken , Ohnishi Ai , Abe Kaoru , Kimura Satoshi , Oono Hideto , Hori Shingo , Nakamura Yoshiro
Published: August 2005

A murine cell line, Swiss 3T3, is commonly used for the study of cellular growth. The present study revealed that this cell line possesses high‐affinity receptors for endothelin, a vasoactive peptide derived from vascular endothelial cells. In this cell line, endothelin potentiated DNA synthesis stimulated by platelet‐derived growth factor, basic fibroblast growth factor or insulin. The endothelin concentration required for potentiating DNA synthesis in this cell line is almost the same as that reported previously in endothelin‐induced vasoconstriction. Since endothelin increased intracellular calcium levels, this ion may participate in the signal transduction pathways by which endothelin induces potentiation of DNA synthesis.
Quantitative Distribution of Cluster 1 Small Cell Lung Cancer Antigen in Cancerous and Non‐cancerous Tissues, Cultured Cells and Sera
Authors: Hirano Takashi , Hirohashi Setsuo , Kunii Tsukasa , Noguchi Masayuki , Shimosato Yukio , Hayata Yoshihiro
Published: August 2005

Three monoclonal antibodies (mAbs), NCC‐LU‐243, ‐244 and ‐246, detected three different epitopes on a 145‐kDa cell membrane antigen, which had been designated as the cluster 1 antigen at the First International Workshop on Small Cell Lung Cancer (SCLC) Antigens. The distribution of the antigen in various tissues, cultured cells and sera was examined by immunohistochemistry and sandwich radioimmunoassay using these mAbs. The antigen is a normal differentiation antigen and is present in nenronal, nenroendocrine and cardiac muscle cells. The level of the antigen was highest in central nervous tissues, while it was undetectable in the liver, kidney and peripheral lung. Among tumor tissues, the antigen was detected only in SCLC, carcinoid tumor and neuroblastoma, indicating its usefulness as a marker for discriminating SCLC from non‐SCLC. The level of the antigen varied among SCLC tissues and tended to be lower in variant‐type cultured SCLC cells. Although an increase in the antigen level was observed in sera of some patients with advanced SCLC, the antigen did not possess any additional value over neuron‐specific enolase as a serum tumor marker for monitoring SCLC patients.
Microvascular Changes in the Stroma of Human Colorectal Carcinomas: Ultrastructural Histochemical Study
Authors: Ohtani Haruo , Sasano Nobuaki
Published: August 2005

Ultrastructural histochemical studies were performed using Ulex europaeus agglutinin‐I lectin (UEA‐I) and anti‐endothelial monoclonal antibody BMA 120 in order to morphologically characterize the microvasculature of human colorectal carcinomas. In the normal mucosa, UEA‐I and BMA 120 were bound to luminal plasma membrane of endothelial cells, usually continuously. Capillaries in the stroma of invasive adenocarcinomas showed remarkable structural changes such as swelling of endothelial cells with well‐developed cell organelles and narrowing of the lumen. Reaction products for UEA‐I and BMA 120 were both observed along the luminal plasma membrane of endothelial cells, usually discontinuously, partially retaining the features of normal capillaries. Furthermore, we have confirmed an occurrence of solid capillary buds composed of a strand of large endothelial cells with a trace of lumen. They showed almost no reactivity to UEA‐I and BMA 120. Conventional electron microscopy revealed that they were present frequently in invasive carcinomas, but infrequently in intramucosal carcinomas and inflammatory lesions. Our results suggest that the stroma of invasive colorectal carcinomas abounds in immature capillaries and their precursors, which may indicate active tumor‐induced angiogenesis.