bluuebunny/crossref_metadata_2025 huggingface dataset:
Low Tumorigenic Response to 3,2′‐Dimethyl‐4‐aminobiphenyl Administration in the Prostate of Rats Castrated at Birth
Authors: Shirai Tomoyuki , Tagawa Yoshiaki , Taguchi Osamu , Ikawa Etsuo , Mutai Mamoru , Fukushima Shoji , Ito Nobuyuki
Published: August 2005

Six‐week‐old rats which had been orchiectomized at birth were given 3,2′‐dimethyl‐4‐aminobiphenyl (DMAB) at various doses combined with a stimulus to prostate epithelial cell proliferation in the form of oral administration of methyltestosterone (MT) for 4 weeks. Thereafter MT treatment was continued or the animals received subcutaneous implants of testosterone propionate (TP) and were maintained until sacrifice at week 60. Although prostatitis and prostatic enlargement were frequently observed, especially in the TP group, numbers of atypical hyperplastic lesions were low and only one prostatic carcinoma in situ developed. Thus, despite the presence of proliferation, castration brought about a significant reduction in susceptibility to DMAB.
Hepatoma Formation in ddY Mice with Chronic Schistosomiasis japonica
Authors: Amano Teruaki , Oshima Tomoo
Published: August 2005

Three hundred and ninety‐five four‐week‐old SPF female ddY mice were each exposed to 5 or 6 cercariae of Schistosoma japonicum (Japanese strain) on their shaved abdomens and were maintained in a conditioned clean environment and fed on sterilized food and water. Fecal examinations at 8 to 10 weeks postinfection (PI) revealed 169 mice to be infected. More than half of them died within 30 weeks PI and 70 mice that survived to the 50th week PI were sacrificed. At autopsy, we could find no schistosome eggs in the liver or intestinal wall of 9 mice, and they were excluded. Out of 61 mice which showed S. japonicum eggs in their livers, 48 had single or multiple hepatoma, while no tumor was observed in the livers of the 60 control mice. The tumors were yellowish‐white in color with distinct boundaries and the centers of the tumors were depressed in some cases. The size of the tumors varied from 1 to 20 mm in diameter. Most of the tumors retained the normal trabecular pattern, but in some cases the trabeculae were thickened, having wide vascular spaces. The tumor cells were PAS‐negative and showed varieties of pleomorphism. The sizes of cells and nuclei varied greatly. These findings suggested some causal relationship between S. japonicum infection and the hepatoma formation in the host's liver. In the chronic course of Schistosomiasis japonica in the endemic areas, S. japonicum infection probably plays a role in hepatoma formation of patients.
Inhibition of Aminoimidazoquinoxalinc‐type and Aminoimidazol‐4‐one‐type Mutagen Formation in Liquid Reflux Models by l‐Tryptophan and Other Selected Indoles
Authors: Jones R. Conrad , Weisburger John H.
Published: August 2005

The essential amino acid l‐tryptophan (l‐Trp) was found to be an effective inhibitor of the development of mutagenicity (Ames test) in liquid‐reflux models known to produce identified IQ‐type mutagens, such as 2‐amino‐3,8‐dimethylimidazo[4,5‐f]quinoxaline (MeIQx) and 2‐amino‐3,7,8‐trimethylimidazo[4,5‐f]qninoxaline (7,8‐DiMeIQx), and in reflux models recently developed in our laboratory that have been found to produce novel IQ‐“like” mutagens (aminoimidazol‐4‐ones), which we have identified as 2‐amino‐1‐methyl‐5‐propylideneimidazol‐4‐one (TCP‐1), and 2‐amino‐5‐ethylidene‐1‐methylimidazol‐4‐one (TCP‐2 or ACP). Selected indoles other than l‐Trp were also found to be effective inhibitors of mutagen formation in these same reflux models. A mechanism of inhibition of mutagen formation based on the preferential reaction of mutagen precursor aldehydes with the indole‐ring nitrogen of these inhibitors, rather than with creatinine, is indicated, and a new “concerted condensation model” for the formation of IQ‐type mutagens proposed.
Validity of Short‐term Examination for Antipromoters of Bladder Carcinogenesis
Authors: Kakizoe Tadao , Takai Kazuhiro , Tobisu Ken‐ichi , Ohtani Mikinobu , Sato Shigeaki
Published: August 2005

Various compounds were screened for antipromoter activity in bladder carcinogenesis in rats with a view to using them clinically to inhibit postoperative intravesical ectopic tumor growth of superficial papillary bladder cancer. Their inhibitions of the effect of sodium saccharin in maintaining increased agglutinability of bladder cells by concanavalin A were examined in 4‐week tests. The compounds found to inhibit the effect of saccharin were α‐tocopherol, ascorbic acid, aspirin, all‐trans aromatic retinoid, α‐difluoromethylornithine, sodium cyanate and p, p′‐diaminodiphenylmethane. Considering the toxicities of some of these chemicals, ascorbic acid and α‐difluoromethylornithine were concluded to be the most promising for future clinical trials.
A Transplantable Cell Line Derived from Spontaneous Hepatocellular Carcinoma of the Hereditary Hepatitis LEC Rat
Authors: Masuda Ryuichi , Yoshida Michihiro C. , Sasaki Motomichi , Dempo Kimimaro , Mori Michio
Published: August 2005

A serially transplantable rat hepatocellular carcinoma (HCC) line was established. The primary spontaneous HCC which developed in a 506‐day‐old male hereditary hepatitis LEC rat was inoculated into young LEC rats. Only this HCC of 18 primary HCCs was successful in serial transplantation. The established cell line was histologically identical to the primary HCC showing a well‐differentiated type with a trabecular structure of tumorous hepatocytes. The characteristic of albumin production was maintained. Chromosome analysis revealed rather widely dispersed polyploid chromosome numbers with a modal value at 96. Every metaphase contained two to five unusually large marker chromosomes.
Immunohistochemistry of Human Gastrointestinal Cancer‐associated Antigen Detected by Monoclonal Antibody PA 8‐15
Authors: Yoshimura Ryuta , Sakamoto Kiyoshi , Egami Hiroshi , Akagi Masanobu
Published: August 2005

A murine monoclonal antibody (MAb), PA 8‐15, was produced against a newly established human pancreatic adenocarcinoma cell line, SUIT‐2. With the avidin‐biotin immunoperoxidase technique, PA 8‐15 MAb reacted strongly with 27 of 28 formalin‐fixed paraffin‐embedded pancreatic adenocarcinoma tissues. All six gall bladder carcinomas and all nine biliary tract carcinomas also showed positive reactions. In addition, PA 8‐15 MAb reacted with gastric carcinomas (6/10), colorectal carcinomas (7/11), and some other primary adenocarcinomas. The distribution of PA 8‐15 antigen on the same tissues of pancreatic cancer was different from those of CA 19‐9 and DU‐PAN‐2 antigens and CEA. PA 8‐15 MAb stained only the epithelium of the pancreatic duct, gall bladder and bile duct in normal adult tissues, and some normal fetal glandular epithelial cells. However, PA 8‐15 MAb was not reactive with inflammatory or benign tumors of the digestive system except for the epithelium, as was seen in normal adults. Reactivity of PA 8‐15 MAb with tissue specimens largely disappeared after treatment with neuraminidase, while oxidation with periodate or trypsin digestion did not alter the staining intensity, indicating that antigenic determinants may be at least partly of sialylated carbohydrate nature. These results suggest that PA 8‐15 MAb detects a new oncofetal antigen in gastrointestinal cancers, especially of the pancreatico‐biliary tract.
The Induction of Bladder Tumors in F344 Rats by Intravesicular Administration of Some Nitrosamines*1
Authors: Thomas Barbara J. , Kovatch Robert M. , Lijinsky William
Published: August 2005

Three nitrosamines, metabolically related and formed in vivo from the bladder carcinogen nitrosomethyl‐n‐octylamine, were administered to groups of 12 female F344 rats by intraurethral instillation twice a week for 30 weeks. All three compounds induced tumors in the urinary bladder. Nitrosomethyl‐2‐oxopropylamine at 10 mg/ml was the most potent, causing death of half of the animals with tumors at 43 weeks, following a total dose of 1.0 mmol; most of the rats also had tumors of the nasal mucosa, and there were some tumors of the kidney and kidney pelvis. Nitrosomethyl‐2‐hydroxypropylamine at 10 mg/ml (total dose 1.0 mmol) was much less effective, the median week of death being 83 weeks. In addition to bladder tumors, this group had tumors of the nasal mucosa, esophagus, and kidney. Nitrosomethyl‐3‐carboxypropylamine at 75 mg/ml and a total dose of 6.2 mmol per rat induced a high incidence of bladder tumors and tumors of the kidney pelvis, but not tumors of the nasal mucosa; the median week of death for this group was 55 weeks. It is concluded that nitrosomethyl‐n‐alkylamines that induce bladder tumors by oral administration to rats are metabolized to nitrosomethyl‐3‐carboxypropylamine, which is excreted in the urine and further metabolized to nitrosomethyl‐2‐oxopropylamine, the proximate bladder carcinogen.
Establishment and Characterization of a Woodchuck Hepatocellular Carcinoma Cell Line (WH44KA)
Authors: Abe Kenji , Kurata Takeshi , Yamada Ken‐ichiro , Okumura Hideo , Shikata Toshio
Published: August 2005

A continuous cell line was established from a hepatocellular carcinoma obtained from a woodchuck that was sero‐positive for woodchuck hepatitis virus (WHV). The cell line, designated WH44KA, grows as an adhering monolayer with a doubling time of 36 hr in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum. The cells not only showed epithelial origin on light and electron microscopic examination but also possess biosynthetic markers of the latter, such as albumin and α‐fetoprotein, which were demonstrated in cultured cells. When they were transplanted into athymic nude mice, tumors developed at the site of inoculation. These tumors were shown to he hepatocellular carcinoma, similar in morphology to the original tumor from which the WH44KA cells were derived. Chromosome analysis revealed a chromosome number ranging from 31 to 126, with a modal number of 35. Integration of WHV DNA was shown by Southern blot analysis. However, WHV surface antigen was not demonstrated in the cultured cells or supernatant medium. The WH44KA cell line appears to be a useful in vitro model for the study of virus‐induced hepatocellular carcinoma.
Clinical Application of Phorbol Diester‐induced Leukemic Cell Differentiation for the Definite Diagnosis of Acute Leukemias
Authors: Ohta Masatsugu , Takaku Fumimaro , Miura Yasusada , Kitagawa Sei‐ichi , Saito Masaki
Published: August 2005

Seventy‐three patients with acute leukemias or chronic myelogenous leukemias in blast crisis were evaluated as to the susceptibility of their leukemic cells to differentiation induction by a chemical agent, 12‐O‐tetradecanoyl phorbol‐13‐acetate (TPA). Leukemic cells of myeloid origin treated with TPA showed monocyte‐macrophage‐lineage differentiation morphologically and functionally, whereas those of lymphoid origin did not. We applied these differentiation phenomena for the clinical diagnosis of three leukemia cases in whom it was difficult to determine whether the leukemic cells were of non‐lymphoid or lymphoid origin, although all the regular diagnostic procedures available had been performed. We successfully diagnosed these three cases by utilizing the above differentiation phenomena. Furthermore, this technique was clinically beneficial as to the choice of adequate chemotherapy in each of these leukemia cases. These findings confirm that the responsiveness to TPA of leukemic cells is of clinical usefulness for the definite diagnosis of acute leukemias.
The Mechanisms of Cytotoxicity to Tumor Cells by Polymorphonuclear Leukocytes Stimulated with Cytokines
Authors: Hayashi Tomohiro , Arai Shigeru , Sendo Fujiro
Published: August 2005

The mechanisms of tumor cytotoxicity of rat polymorphonuclear leukocytes (PMN) activated with cytokine(s) were studied with the use of supernatants from a rat myelomonocytic leukemia cell line, WRT‐7, incubated in the presence of bacterial lipopolysaccharide (LPS) (LPS WRT‐7 sup) as a source of cytokine. Rat peritoneal PMN treated with LPS WRT‐7 sup showed cytostasis from 3 hr after the start of incubation, while significant cytolysis was first observed after 24 hr. When target tumor cells were separated from PMN at 6 or 12 hr after the start of the assay, 3H‐UdR release from the separated target cells comparable to that from the group incubated with PMN for the whole assay time of 40 hr was observed during the following incubation, which indicates that priming for subsequent lysis occurs at a relatively early stage of the assay. None of various scavengers of active oxygens, inhibitors of heme enzymes, and inhibitors of neutral proteinases inhibited cytolysis mediated by PMN stimulated with LPS WRT‐7 sup. Heparin inhibited PMN cytolysis only when it was added within 1 hr after the start of the assay. Fractionation of heparin by ion exchange chromatography showed a parallelism between the negative charge and the inhibitory effect of heparin on PMN cytotoxicity.
Endogenous Tumor Necrosis Factor Induction with Bordetella pertussis Vaccine as a Triggering Agent and Its Therapeutic Effect on MM46 Carcinoma‐bearing Mice
Authors: Minagawa Harushige , Kakamu Yoshiyuki , Yoshida Hajime , Tomita Fusao , Oshima Haruyuki , Mizuno Den'ichi
Published: August 2005

Induction of endogenous tumor necrosis factor (TNF) by administration of Bordetella pertussis vaccine (BPV) as a triggering agent and its therapeutic effect against MM46 carcinoma were investigated in C3H/He mice. Test triggering agents were injected intravenously into mice after intravenous injection of 4‐fold dilution of macrophage activating factor (MAF) or 104 units of murine interferon‐γ (Mu‐IFN‐γ). Then sera were obtained from the mice, and their TNF activities were assayed on L‐929 cells by the method of Ruff and Gifford. The triggering activity of BPV was the highest among those of conventional triggers, such as lipopolysaccharide (LPS) of Escherichia coli, and OK‐432. The levels of serum TNF activity triggered by BPV (4 × 109 cells), LPS of E. coli (3 μg) and OK‐432 (3 KE) were 5350, 85 and 102 units/ml, respectively. Growth of MM46, a spontaneous mammary carcinoma cell line of C3H/He was observed for 35 days after tumor inoculation and was suppressed significantly by intravenous injection of MAF and BPV (4 × 109 cells). On local injection of BPV (2 × 109 cells) into murine tumors, complete regression was observed in 67% of the mice tested with or without MAF priming on day 25 after tumor inoculation, and intratumoral TNF activity was observed even in the case of the single injection of BPV.
DEFECTIVE HUMAN IMMUNO‐DEFICIENCY VIRUS (HIV) PARTICLES PRODUCED BY CLONED CELLS OF HTLV‐I‐CARRYING MT‐4 CELLS PERSISTENTLY INFECTED WITH HIV
Authors: Ikuta Kazuyoshi , Morita Chizuko , Nakai Masuyo , Yamamoto Naoki , Kato Shiro
Published: August 2005

Persistently HIV‐infected cell lines were isolated from surviving and proliferating cells after infection of HTLV‐I‐carrying MT‐4 cells with cell‐free human immunodeficiency virus (HIV); HTLV‐IIIB and LAV. The media of the cloned cell cultures did not cause HIV infection of MT‐4, MOLT‐4, TALL‐1, or HL‐60 cells. Most of the constituents of the virus in the media were env proteins and many defective doughnut‐shaped particles released from the cells were identified by electron microscopy.
A SOLUBLE‐FACTOR(S) SECRETED BY A HUMAN SKIN CANCER CELL LINE SUPPORTS CLONAL GROWTH OF ADULT T‐CELL LEUKEMIA CELLS
Authors: Kagami Yoshitoyo , Kinoshita Tomohiro , Shimoyama Masanori , Miwa Masanao
Published: August 2005

Leukemic cells from four out of eight patients with adult T‐cell leukemia (ATL) were successfully grown by cocultivation with HSC‐I cells, a human skin cancer cell line, in the presence of interleukin‐2. Three of these four cultures of growing cells showed rearrangement of the T‐cell receptor β‐chain gene like the original leukemic cells in vivo, and also showed conservation of the patterns of HTLV‐I integration of the original leukemic cells in vivo. Cell‐to‐cell contact between HSC‐I cells and leukemic cells was not necessary for growth of the leukemic cells. The results indicate that some soluble growth factor secreted by HSC‐I cells and interleukin‐2 are required for the in vitro growth of leukemic cells from some patients with adult T‐cell leukemia.
DIFFERENTIAL EXPRESSION OF CARCINOEMBRYONIC ANTIGEN AND NONSPECIFIC CROSSREACTING ANTIGEN GENES IN HUMAN COLON ADENOCARCINOMAS AND NORMAL COLON MUCOSA
Authors: Sato Chieko , Miyaki Michiko , Oikawa Shinzo , Nakazato Hiroshi , Kosaki Goro
Published: August 2005

The level of mRNA for carcinoembryonic antigen (CEA) and nonspecific crossreacting antigen (NCA) in human colon adenocarcinomas and normal colon mucosa was analyzed by Northern blot hybridization using as probes 32P‐labeled CEA cDNA and synthetic oligodeoxyribonucleotides specific to CEA and NCA mRNA sequences. The major 3.5‐kb mRNA and a minor 4.2‐kb mRNA are shown to be CEA‐specific and expressed in both tissues, albeit at slightly different degrees, suggesting that the expression of CEA is regulated posttranscriptionally. Another minor mRNA of 2.9 kb is NCA‐specific and expressed predominantly in cancerous tissues, suggesting its usefulness as a marker for colon cancer.
Effects of Phenobarbital and Carbazole on Carcinogenesis of the Lung, Thyroid, Kidney, and Bladder of Rats Pretreated with N‐Bis(2‐hydroxypropyl)nitrosamine
Authors: Shirai Tomoyuki , Masuda Atsuko , Imaida Katsumi , Ogiso Tadashi , Ito Nobuyuki
Published: August 2005

Studies were made on potential modifying effects of phenobarbital (PB) and carbazole on tumor development induced by N‐bis(2‐hydroxypropyl)nitrosamine (DHPN), a wide‐spectrum carcinogen in rats. Effects on the lung, thyroid, kidney, bladder and liver were investigated. Male F344 rats were given 0.2% DHPN in their drinking water for 1 week and then 0.05% PB or 0.6% carbazole in their diet for 50 weeks. Control animals were treated with either DHPN or PB or carbazole only. Neither PB nor carbazole affected the incidence or histology of lung tumors. However, PB promoted the development of thyroid tumors and preneoplastic lesions of the liver, while carbazole promoted the induction of renal pelvic tumors.
Enzyme‐altered Liver Cell Foci in Woodchucks Infected with Woodchuck Hepatitis Virus
Authors: Abe Kenji , Kurata Takeshi , Shikata Toshio , Tennant Bud C.
Published: August 2005

The histochemical characteristics of liver cell foci in woodchucks were investigated. The foci appeared to be distributed throughout the liver and were observed only in the woodchuck hepatitis virus (WHV)‐positive animals, including all 19 woodchucks with hepatocellular carcinoma(HCC), and 7 without HCC. No foci appeared in 11 WHV‐negative animals. Histochemical studies revealed that liver cell foci and carcinoma cells were characterized by positive gamma‐glutamyl transpeptidase (GGT) enzymatic reactions and decreased glucose‐6‐phosphatase enzyme activity compared to non‐neoplastic liver. Furthermore, serum GGT was significantly elevated in almost all of the animals which had larger carcinomas. Ultrastructural findings of foci showed some resemblance to carcinoma cells, being characterized by abundant free ribosomes within the cytoplasm and undeveloped endoplasmic reticulum. These results suggest that the liver cell foci are potential precursors of HCC in WHV‐infected animals, and that serum GGT may be a useful marker for indicating the development of carcinoma.
Immunogenotypes of Lymphoid Malignancies; the Rearrangement of T Cell Receptor β Chain Gene Can Occur before the γ Chain Gene Rearrangement
Authors: Miwa Hiroshi , Nosaka Tetsuya , Kita Kenkichi , Ohno Toshiyuki , Matsuoka Nobuyoshi , Shirakawa Shigeru , Arita Yuu , Doi Shouichi , Nishikori Masaru , Honjo Tasuku , Hatanaka Masakazu
Published: August 2005

Immunoglobulin (Ig) and T cell receptor (TcR) gene rearrangements were analyzed in 101 cases of lymphoid malignancies in association with a surface phenotype study. In leukemias/lymphomas with mature phenotype, there is a good correlation between phenotypes and genotypes. However, in leukemias/lymphomas with immature phenotype, we found many discordances between phenotypes and genotypes, suggesting the stochastic nature of hematopoietic cell differentiation at the early stage. As for TcR β and γ chains, the rearrangement of γ chain gene is considered to occur slightly prior to that of β chain gene. However, we observed a mature T cell malignancy, adult T‐cell leukemia, with rearranged β chain gene and germ line γ chain gene, showing the possible existence of another pathway of T cell differentiation.
Further Characterization of Bleomycin‐resistant HeLa Cells and Analysis of Resistance Mechanism
Authors: Urade Masahiro , Sugi Masakazu , Matsuya Tokuzo
Published: August 2005

Bleomycin (BLM)‐resistant HeLa cells (HeLa‐BLMr), which have been subcultured for more than 150 passages during over 2 years in the presence of 1 μg/ml of BLM and stably possess a 20‐fold‐increased BLM‐resistance in vitro, were further characterized. The nude mouse tumors produced by HeLa‐BLMr were significantly less sensitive (P < 0.005–0.01) to BLM administration than those produced by HeLa cells, and the cells primarily cultured from nude mouse tumors of HeLa‐BLMr and transplanted serially 5 times in the absence of BLM also exhibited a similar degree of BLM resistance to that of HeLa‐BLMr cultured in BLM‐containing medium. The BLM‐resistance mechanism of HeLa‐BLMr was partially analyzed. The cells showed about 40% decreased accumulation and 2–3 times reduced retention of [3H]peplomycin, a novel BLM analog, as compared to HeLa cells, but the BLM‐hydrolase activity was at almost the same level as that of HeLa cells when determined by HPLC. Furthermore, alkaline sucrose gradient analysis of cellular DNA after BLM treatment revealed that the damaged DNA was more efficiently repaired in HeLa‐BLMr than in HeLa cells. These results suggest that decreased drug accumulation and retention, and elevated DNA repair activity are the main mechanisms of BLM resistance in HeLa‐BLMr.
The Presence of CA19‐9 in Serum and Saliva from Lewis Blood‐group Negative Cancer Patients
Authors: Yazawa Shin , Asao Takayuki , Izawa Hideaki , Miyamoto Yukio , Matta Khushi L.
Published: August 2005

Eighteen cancer patients showed high levels of CA19‐9 in sera, even though the blood‐group phenotypes of their red blood cells were Le(a — b —). Seven of these patients (group I) were determined as Le(a — b —) from both red blood cells and saliva consistently, whereas eleven other patients (group II) secreted either Lea or Leb antigen in saliva and showed the expression of incompatible Lewis blood‐group antigens. GDP‐fucose: N‐acetyl‐glucosaminide a(1 × 4)‐L‐fucosyltransferase was demonstrated to be present in salivas from both group I and group II. These results suggest that a cancer‐associated alteration of Lewis blood‐group antigen expression occurs in cancer patients.
Dose‐dependent Induction of Liver and Thyroid Neoplastic Lesions by Short‐term Administration of 2‐Amino‐3‐methylimidazo[4,5‐f]quinoline Combined with Partial Hepatectomy Followed by Phenobarbital or Low Dose 3′‐Methyl‐4‐dimethylaminoazobenzene Promotion
Authors: Tsuda Hiroyuki , Asamoto Makoto , Ogiso Tadashi , Inoue Tadashi , Ito Nobuyuki , Nagao Minako
Published: August 2005

Dietary administration of 0.1, 0.05, or 0.025% 2‐amino‐3‐methylimidazo[4,5‐f]quinoline (IQ) for two weeks combined with partial hepatectomy at the end of the first week and followed by long‐term treatment with phenobarbital (PB) or 3′‐methyl‐4‐dimethylaminoazobenzene (3′‐MeDAB) from week 3 to week 86 resulted in dose‐dependent development of liver and thyroid neoplastic and preneoplastic lesions. Quantitation of glutathione S‐transferase placental form (GST‐P)‐positive hepatocellular focal populations revealed a significant correlation of IQ concentration with lesion area, with a yield approximately equal to that generated by a similar dose of 2‐acetylaminofluorene. The fact that IQ was less toxic therefore allowed greater yields of hepatocellular carcinomas to be induced. The development of thyroid tumors initiated by the IQ treatment was significantly enhanced by the administration of PB, whereas Zymbal gland tumors induced by IQ did not show any correlation with either PB or 3′‐Me‐DAB treatment.
Isolation of Genomic DNA Controlling Mouse Melanoma Antigen Defined by Monoclonal Antibody
Authors: Okitsu Akira , Tagawa Masatoshi , Tamura Yoshio , Kanno Masamoto , Matsubara Hisahiro , Ito Toshihiro , Imai Kenji , Shigemoto Kazuhiro , Nakamura Ikuro , Koseki Haruhiko , Lau Yun‐Fai , Taniguchi Masaru
Published: August 2005

We have isolated the genomic DNA controlling the expression of murine specific melanoma antigen by employing cosmid shuttle vector and monoclonal antibody. Transfection of the cosmid library derived from mouse melanoma cells into human melanomas and repeated cell sortings of the fluorescence‐bright population enabled us to enrich the antigen‐positive transfectants. We rescued a 34.8 kb DNA fragment from the transfectants by in vitro packaging and showed it to be responsible for the antigen expression. However, we noticed instability of the antigen expression when the selection pressure imposed by the cell sorting was removed. This seemed to be due to the fact that the insert DNA was preferentially deleted from this cosmid vector without loss of the vector sequence itself.
Radiation Responses of Subrenally Transplanted Syngeneic and Allogeneic Mouse Fibrosarcomas
Authors: Sato Setsu , Ootsuyama Akira , Tanooka Hiroshi
Published: August 2005

The radiation responses of two tumor types transplantable into C3H/He mice and differing in radiosensitivity, i.e., 3‐methylcholanthrene (MCA)‐induced fibrosarcoma and NFSa fibrosarcoma, were investigated using the subrenal capsule assay. Subrenal tumor growth was histologically confirmed. Volume regression and regrowth of subrenal capsule‐implanted and subcutaneously implanted tumors after X‐irradiation were compared. No difference was found in tumor growth speed (volume doubling time: 1.2–1.3 days) between the subrenal transplants into C3H/He mice, syngeneic to the tumor grafts, and those into immuno‐incompetent C57BL mice, allogeneic to the tumor grafts. The tumor growth rates for subrenal capsule transplants were 1.7‐ to 1,8‐fold higher than those for subcutaneous transplants of the same tumor type. A marked difference was found in the radiation responses of the two tumor types by the subrenal capsule assay, i.e., tumor regrowth time following 20 Gy irradiation was more than 8 days for MCA‐induced fibsarcoma and 4.5–5.4 days for radioresistant NFSa fibrosarcoma. These values correlate well with the estimated radiation sensitivities of these tumors.
Performance Certification of Gelatin Particle Agglutination Assay for Anti‐HTLV‐1 Antibody: Inconclusive Positive Results
Authors: Maeda Yoshiaki , Imai Joko , Kiyokawa Hiroyuki , Kanamura Machiko , Hino Shigeo
Published: August 2005

In order to test the performance of particle agglutination assay (PA), 800 preselected PA‐positive sera at 8 blood centers in the Kyushu area were tested in various assays. Most blood centers should improve their PA technique, since a third of the samples were PA‐negative in our hands. A third of our PA high‐titer sera were negative in indirect immunofluorescence and enzyme imiminoassay, the results of which were consistent with each other. Western blots did not detect every positive serum. PA inhibition positivity was not consistent with PA titer. Most IgM antibody‐positive sera also contained IgG antibody. PA should be used in combination with other methods before notifying the results to positive testees.
Change in Methylation Status of DNA of Remaining Allele in Human Lung Cancers with Loss of Heterozygosity on Chromosomes 3p and 13q
Authors: Shiraishi Masahiko , Sekiya Takao
Published: August 2005

Loss of heterozygosity at several chromosomal loci is frequently observed in human cancers and loss of one allele is supposed to affect expression of the gene(s) in the remaining allele. As DNA methylation is known to be closely related to gene expression in vertebrates, we are interested in the methylation status of the regions of alleles remaining after loss of their counterparts. In this work we investigated the methylation status of DNA from human lung carcinoma in which heterozygosity was lost at 3p and 13q and found that the remaining allele at these loci was preferentially demethylated. In contrast, tumor DNAs without allele loss tended to retain highly methylated states. These results suggest that in tumors, change of the DNA methylation status is closely related with allele loss, and vice versa.
Secretion of Transforming Growth Factor‐ß by Human Myelogenous Leukemic Cells and Its Possible Role in Proliferation of the Leukemic Cells
Authors: Komatsu Keiko , Nakamura Hiroyuki , Shinkai Kiyoko , Akedo Hitoshi
Published: August 2005

Transforming growth factor(TGF)‐ß activity was found in the neutral extracts of human myelogenous leukemic cells or K562 cells and the conditioned medium from K562 cell culture. BALB/c 3T3 cells grown in soft agar in the presence of TGF‐ß1 produced an activity that stimulated the growth of K562 cells. This activity was non‐dialyzable. acid‐stable, heat‐sensitive and partially Inactivated by pronase treatment. These results suggest a mutual growth reliance between the leukemic cells and fibroblasts mediated by paracrine growth factors produced by these cells.
A Case‐Control Study of Biliary Tract Cancer in Niigata Prefecture, Japan
Authors: Kato Kiyoshi , Akai Sadahiko , Tominaga Suketami , Kato Ikuko
Published: August 2005

A case‐control study of biliary tract cancer was conducted in Niigata prefecture where the mortality of the cancer is the highest in Japan. The cases were 109 patients with gallbladder cancer and 84 with bile duct cancer, and the controls were 386 sex‐ and age‐matched neighborhood controls. For gallbladder cancer, a past history of biliary tract disease, a positive family history of cholelithiasis and a taste for oily foods were high risk factors. Intakes of animal proteins and fats such as fish, eggs, meat, etc., ingestion of vegetables and fruits, and taking snacks were low risk factors for gallbladder cancer. For bile duct cancer, a past history of biliary tract disease, a family history of cerebral vascular accident, a thin constitution and taking a small amount of foods were high risk factors, and a family history of heart disease, obesity, intakes of alcohol, animal proteins and fats, or frequent intakes of vegetables and fruits were low risk factors.
Synergistic Effects of Low‐dose Hepatocarcinogens in Induction of Glutathione S‐Transferase P‐positive Foci in the Rat Liver
Authors: Hasegawa Ryohei , Mutai Mamoru , Itnaida Katsumi , Tsuda Hiroyuki , Yamaguchi Shuji , Ito Nobuyuki
Published: August 2005

The effects of combined administration of hepatocarcinogens at low doses on the development of glutathione S‐transferase P‐form (GST‐P)‐positive foci of rat liver were examined utilizing a bioassay model which consists of a single injection of diethylnitrosamine (DEN, 200 mg/kg, ip), two‐thirds partial hepatectomy at week 3 and a 6‐week administration of test compounds. The chemicals used, 2‐acetylaminofluorene (2‐AAF), 3′‐methyl‐4‐dimethylaminoazobenzene (3′‐Me‐DAB), phenobarbital (PB), thioacetamide (TAA), N‐ethyl‐N‐hydroxyethylnitrosamine (EHEN), benzo[a]pyrene (B[a]P), carbazole, and α‐hexachlorocyclohexane (α‐HCH) were incorporated in the diet, except for EHEN which was dissolved in the drinking water, at levels of 1/6 of the doses usually used. The combinations were: I) 2‐AAF, 3′‐Me‐DAB, PB, TAA, EHEN and B[a]P, II) 2‐AAF, 3′‐Me‐DAB and PB, III) TAA, EHEN and B[a]P, IV) 2‐AAF, 3′‐Me‐DAB, carbazole, TAA, EHEN and a‐HCH, V) 2‐AAF, 3′‐Me‐DAB and carbazole, and VI) TAA, EHEN and α‐HCH. All combinations, except for II, caused an increase in the area of the foci as evaluated by the ratios of areas in the combined administration groups to the sum totals of 3 or 6 individual data: I) 1.75, II) 0.81, III) 2.01, IV) 3.62, V) 1.34 and VI) 2.91. The non‐synergistic effect in combination II might be related to PB induction of hepatic microsomal enzymes leading to enhanced enzymatical detoxification of 2‐AAF and 3′‐Me‐DAB. The present results indicate that exposure to several chemicals of similar organotropism, even at doses lower than the apparent carcinogenic levels, might be critical to the carcinogenic process.
Molecular Forms of Human Chorionic Gonadotropin in Choriocarcinon Serum and Urine
Authors: Nishimura Ryuichiro , Kitajima Takashi , Hasegawa Kazuo , Takeuchi Kunio , Mochizuki Matsuto
Published: August 2005

The molecular forms of human chorionic gonadotropin (hCG) were assessed in parallel serum and urine samples from a choriocarcinoma patient by gel chromatography, isoelectric focusing, and Western blot analysis. There were significant qualitative differences in the molecular forms of hCG between the serum and the urine. The serum hCG had a greater molecular weight and a stronger acidic charge than the urinary hCG. These results may be attributed to differences of sialic acid contents. Affinity chromatography using Ricinus communis agglutinin‐conjugated Sepharose showed that the serum hCG was completely sialylated, while the urinary hCG was partially desialylated. In addition to the complete hCG molecule, two kinds of hCGβ‐related fragments were detected in the urine of the patient, but not in the serum. In the Western blot using anti‐hCGβ or anti‐hCGβ‐CTP under reducing conditions, the urine presented a new band (CTP′) with Mr 23,000 in addition to the β‐subunit, while the serum revealed a single band of the β‐subunit with or without a reducing reagent. The present data revealed striking qualitative differences in the molecular forms of hCG between serum and urine of a patient with choriocarcinoma.
Elevated Concentrations of Brain‐type Glycogen Phosphorylase in Renal Cell Carcinoma
Authors: Takashi Munehisa , Koshikawa Takashi , Kurobe Naomi , Kato Kanefusa
Published: August 2005

We determined tissue concentrations of brain‐type glycogen phosphorylase in normal kidney and renal cell carcinoma by enzyme immunoassay; we also localized it immunohistochemically. Tissue concentration of brain‐type glycogen phosphorylase in the renal cortex (n = 13) was 1430±709 ng/mg protein (mean±standard deviation) and that in the medulla (n = 13) was 1270±635 ng/mg protein. On the other hand, the concentration in renal cell carcinoma (n = 26) was 2530±1540 ng/mg protein, ranging from 520 to 6860 ng/mg, significantly higher than those in renal cortex and medulla. Clear cell type tumors contained slightly higher levels of the phosphorylase (2600±1430 ng/mg protein) than granular cell type tumors (2100±1520 ng/mg protein). In renal tissues, brain‐type glycogen phosphorylase was immunohistochemically localized in epithelial cells of proximal and distal tubules, collecting tubules, thick and thin limbs of loops of Henle, and Bowman's capsules. In renal cell carcinoma, the phosphorylase was immnnohistochemically demonstrated in 97% (34/35) of cases, including one sarcomatoid variant. These findings indicate that renal cell carcinoma cells contain enhanced tissue levels of brain‐type glycogen phosphorylase.
Density of GM3 with Normal Primary Structure Determines Mouse Melanoma Antigenicity; a New Concept of Tumor Antigen
Authors: Harada Yoshitada , Sakatsume Minoru , Nores Gustavo A. , Hakomori Sen‐itiroh , Taniguchi Masaru
Published: August 2005

We attempted to induce anti‐melanoma cytotoxic T cells (CTL) and suppressor T cells (Ts) inhibiting CTL generation by using liposomes carrying various densities of GM3 as tumor antigens. We found that liposomes carrying 6–16 mol% of GM3 with normal primary structure successfully generated anti‐melanoma CTL and suppressor T cells, while liposomes with GM3 outside this range had little or no such activity. Anti‐melanoma CTL induced by GM3(NeuGc)‐liposomes belonged to CD4‐/CD8‐double‐negative CD3+ CTL while GM3(NeuAc)‐liposomes induced two types of T cells, CD4+ T cells and double‐negative I‐J positive T cells which mediated inhibition of the induction of anti‐melanoma CTL responses. These cell types were tbe same as those induced by mitomycin C‐treated melanoma cells for CTL induction and soluble melanoma antigen for Ts generation. The results clearly demonstrate that even GM3 with normal primary structure can, at a certain density, generate melanoma antlgenicity.
Multidrug Resistance in Cultured Human Leukemia and Lymphoma Cell Lines Detected by a Monoclonal Antibody, MRK16
Authors: Ishida Yasushi , Ohtsu Tomoko , Hamada Hirofumi , Sugimoto Yoshikazu , Tobinai Kensei , Minato Keisuke , Tsuruo Takashi , Shimoyama Masanori
Published: August 2005

Forty cultured human leukemia and lymphoma cell lines never exposed to anticancer agents in culture, apart from doxorubicin (ADM)‐resistant K562/ADM, were examined for reactivity with a monoclonal antibody, MRK16 in F(ab′)2 form [MRK16‐F(ab′)2], which recognizes P‐glycoprotein (P‐gp). The relative resistance index to various drugs was calculated by dividing the 50% growth inhibitory concentration (IC50) of the test cell line by IC50 of K562, which was the negative control in the antibody experiment. MRK16‐F(ab′)2 reacted with four cell lines, K562/ADM, KYO‐1, HEL and CMK, which had relative resistance index values of 2 or more to vincristine (VCR), vindesine, vinblastine, ADM, daunorubicin, mitoxantrone (MIT), etoposide (VP‐16) and actinomycin‐D (ACT‐D). The level of resistance to VCR and ADM in these cell lines decreased significantly in the presence of 10 μM verapamil in vitro. Significant expression of mRNA of P‐gp gene was also detected in K562/ADM, KYO‐1 and HEL. MRK16‐F(ab′)2 did not react with 36 other cell lines. Among them, three cell lines, PL‐21, P31/FUJ and KOPM‐28, had relative resistance index values of 2 or more to anthracyclines, MIT and VP‐16, but not to vinca alkaloids or ACT‐D. The level of ADM‐resistance in these cell lines did not decrease significantly in the presence of 10 μM verapamil. Five cell lines, ATL‐1K, HL‐60, KMOE‐2, ML‐1 and U266, had relative resistance index values of 2 or more to some of the drugs, but not to the others, and 19 other cell lines did not. These results indicate that the reactivity of MRK16‐F(ab′)2 correlates with a relative resistance index of 2 or more to all these drugs in cultured human leukemia and lymphoma cell lines.
DNA Modification by 2‐Amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine in Rats
Authors: Takayama Kyoko , Yamashita Katsumi , Wakabayashi Keiji , Sugimura Takashi , Nagao Minako
Published: August 2005

2‐Amino‐l‐methyl‐6‐pheny]imidazo[4,5‐b]pyridine (PhIP) is the most abundant mutagenic heterocyclic amine by weight in cooked foods. This mutagen was found to produce DNA adducts in all ten tested organs of rats using the 32P‐postlabeling method. The level of DNA adducts in the pancreas, kidney and liver increased dose‐dependently and feeding tinie‐dependently up to four weeks. When diet containing 0.05% PhIP was given to rats for four weeks, levels of PhIP‐DNA adducts were relatively high in the lung, pancreas and heart, being around 20 per 107 nucleotides, and lowest in the liver, being 2.20 per 107 nucleotides. Thus, PhIP showed a unique feature in the formation of DNA adducts compared to other mutagenic and carcinogenic heterocyclic amines, which produce the highest level of DNA adducts in the liver.
Detection of Increased Fecal Carcinoembryonic Antigen and Its Characterization as a Membrane‐bound Form in Colorectal Carcinoma and Other Gastrointestinal Disorders
Authors: Sugano Kokichi , Ohkura Hisanao , Hirohashi Setsuo , Shimosato Yukio , Sakurai Yoichi , Kodaira Susumu , Abe Osahiko
Published: August 2005

The levels and character of carcinoembryonic antigen (CEA) in feces were investigated by sandwich radioimmunometric assay using anti‐CEA monoclonal antibodies NCC‐CO‐411 and NCC‐CO‐432. Mean CEA concentration was significantly higher (P< 0.001) in the feces from patients with colorectal carcinoma and other gastrointestinal disorders as compared to normal adults. More than 90% of the fecal CEA was trapped by a 0.22 μm membrane filter and solubilized by treatment with 1% Triton X‐100 or phosphatidyl‐inositol specific phospholipase C. In hydrophobic chromatography, most of the fecal CEA was eluted at the lowest (NH4)2SO4 concentration while serum CEA appeared in the more hydrophilic fractions. These results suggest that the majority of CEA exists in feces as an amphiphilic molecule or a membrane‐bound form. The increase of fecal CEA may reflect the destruction and abrasion of epithelial cells in various gastrointestinal disorders.
Modulation of 7,12‐Dimethylbenz[a]anthracene‐induced Transmammary Carcinogenesis by Disulfiram and Butylated Hydroxyanisole in Mice
Authors: Rao Araga Ramesha , Hussain Syed Perwez , Jannu Laxminarayana
Published: August 2005

The individual as well as combined chemopreventive actions of disulfiram (DSF) and butylated hydroxyanisole (BHA) on 7,12‐dimethylbenz[a]anthracene (DMBA)‐induced transmammary car‐cinogenesis in mice were examined. When nursing mothers receiving normal diet were treated with DMBA (1 mg/mouse) on days 6, 8 and 10 postpartum, the tumor incidence in their 50‐week‐old F1 progeny was 44.1%. When nursing mothers receiving 0.75% BHA diet, 0.5% DSF diet and 0.75% BHA+0.5% DSF diet were similarly treated with DMBA, the tumor incidences in their 50‐week‐old F1 progeny were 14.7% (P<0.05), 12.5% (P<0.05) and 5.8% (P<0.01), respectively. It is concluded that diets containing BHA (0.75%) and DSF (0.5%), singly or in combination, can inhibit trans‐mammary carcinogenesis in Swiss albino mice.
Transcriptional Enhancement of the Human Gene Encoding for a Melanoma‐associated Antigen (ME491) in Association with Malignant Transformation
Authors: Hotta Hak , Takahashi Nobuo , Homma Morio
Published: August 2005

A cloned DNA fragment (λR31) containing the human gene for melanoma‐associated ME491 antigen was transfected into mouse fibroblast cell lines and the antigen expression was studied. Our preliminary observation of higher expression of the antigen in more malignant Ltk cells and weaker expression in less malignant NIH3T3 cells tempted us to investigate the antigen expression in Harvey (H)‐ras‐transformed NIH3T3 cells. It was observed that malignant transformation of the λR31‐transfected NIH3T3 cells by H‐ras oncogene enhanced the antigen expression to some extent. Northern blot analysis suggested that the enhancement occurred at the transcriptionsl level. Nucleotide sequence analysis of the 5′‐regulatory region of the ME491 antigen gene in λR31 identified a number of consensus sequence motifs for binding of transcription factors such as Sp1, AP‐2 and polyomavirus enhancer binding proteins 2 and 3. A consensus sequence motif for binding of AP‐1, known as a ras‐responsive element, was not found in that region. The significance and possible involvement of the transcription factors in the enhancement of ME491 antigen expression are discussed.
Further Characterization of the Human Adrenal‐derived P‐GIycoprotein Recognized by Monoclonal Antibody MRK 16 Reacting with Only Human P‐Glycoprotein
Authors: Sugawara Isamu , Hamada Hirofumi , Nakahama Masao , Okamoto Shingo , Tsuruo Takashi , Mori Shigeo
Published: August 2005

This paper describes further characterization of the 170–180‐kDa glycoprotein (P‐glycoprotein) recognized by the monoclonal antibody MRK 16 in the human adrenal. By electron microscopy, P‐glycoprotein was observed in the adrenal cell membranes. However, MRK 16‐defined P‐glycoprotein was not found in cow, pig, horse, monkey or rabbit adrenal, indicating that MRK 16 recognizes the non‐homologous part of P‐glycoprotein of various species. Eleven out of 16 adrenal tumors including 4 cases of primary aldosteronism and 7 cases of Cushing syndrome were intensely stained with MRK 16, whereas pheochromocytoma, non‐functioning adrenocortical adenoma with no associated increase of serum adrenal‐derived hormones and myolipoma of the adrenal were not. Finally, P‐glycoprotein‐MRK 16‐protein A‐Sepharose complex derived from human adrenal possessed marked ATPase activity. Taken together, these data suggest that P‐glycoprotein may play a physiological role in the human adrenal.
Enhanced ATPase Activity in Liver Cell Nuclei Induced by Administration of Mitomycin C to Rats
Authors: Wakizaka Akira , Imai Hirokazu , Aiba Namiko , Okuhara Eiji
Published: August 2005

Intraperitoneal administration of mitomycin C (40 μg/100 g body weight) to male Wistar rats increased the ATPase activity in hypotonic extracts of liver cell nuclei for 4 days after injection. Partially purified ATPase, obtained by the DEAE‐cellnlose column chromatography of these extracts, showed a 14 times higher specific activity than that found in normal rat liver nuclei. The enzymatic activity was strongly enhanced by the addition of polynucleotides, especially poly A and poly I, to the assay mixture, but was inhibited by GTP, a chelating agent, heparin and thiol‐group inhibitors. Quercetin and oligomycin were less effective, and ouabain showed no inhibitory effect. Mg2+ ions were essential, but neither Ca2+, Na+ nor K+ ions were required for the manifestation of the activity. These characteristic properties of the enzyme are similar to those of a nucleoside triphosphatase found in the nuclear matrix and envelope, suggesting that some energy‐providing mechanisms involved in the repair processes of DNA damage or cellular injury are induced by mitomycin C administration.
Effect of Combined Intrapleural Administration of Lactobacillus casei (LC9018) and Adriamycin on Experimental Malignant Pleurisy in Mice
Authors: Tohgo Akiko , Tanaka Noriko G. , Okada Hirokazu , Osada Yasuaki
Published: August 2005

The combined effect of Lactobacillus casei YIT9018 (LC9018) and adriamycin (ADR) on malignant pleurisy was investigated using an experimental model in BALB/c mice in which Meth A fibrosarcoma cells were intrapleurally implanted. The control mice died from dyspnea due to pleural effusion, before significant growth of tumor nodules could be achieved in the thoracic cavity. Intrapleural (ipl) administration of LC9018 (20–200 μg/head) on days 1 and 5 reduced the effusion volume and induced pleural adhesions in a dose‐related manner. A statistically significant and reproducible prolongation of survival was observed at a dose of LC9018 200 μg/head: increase of lifespan (ILS) values of 15–39% were obtained. An ipl administration of ADR (2–4 mg/kg) on day 1 was also effective in prolonging survival without severe toxicity (ILS values of 100–122%). The combined use of ADR and LC9018 induced a high incidence of pleural adhesions, a delay in effusion accumulation, and an additive prolongation of lifespan (ILS values of 133–178%), compared with ADR monotherapy. In the combination therapy group, a marked and continuous ipl exudation of neutrophils, macrophages, and lymphocytes was observed with a significant decrease in pleural tumor cells. These findings suggest that ipl administration of LC9018 enhances the effect of ADR, probably through both host‐mediated tumoricidal activity and sclerosing effects on the pleura.