bluuebunny/crossref_metadata_2025 huggingface dataset:
Antibodies against p40tax Gene Product of Human T‐Lymphotropic Virus Type‐I (HTLV‐I) under Various Conditions of HTLV‐I Infection
Authors: Kamihira Shimeru , Toriya Kazuhiro , Amagasaki Tatsuhiko , Momita Saburo , Ikeda Shuiti , Yamada Yasuaki , Tomonaga Masao , Ichimaru Michito , Kinoshita Ken‐ichirou , Sawada Takasi
Published: August 2005

We investigated antibodies against pX gene product, p40mx, by ELISA using recombinant p40tax protein in HTLV‐I seropositive carriers as well as patients with adult T cell leukemia (ATL) and HTLV‐I‐associated myelopathy (HAM). Seventy (49.0%) out of 143 HTLV‐I healthy carriers were found to be positive for antibody against p40tax antigen and the follow‐up samples at two‐year intervals revealed constant reactivity by ELISA in each carrier. The onset of antibody production was delayed 4 to 12 weeks as compared with anti‐HTLV‐I in primary infection cases. The anti‐p40tax‐positive rate (90%) in HAM patients was significantly higher than that of healthy carriers, acute and chronic ATL patients and their family members. Furthermore, HAM patients and a few healthy carriers showed high reactivities by ELISA. Children from mothers with anti‐p40tax showed a higher anti‐HTLV‐I‐positive rate than that of children from mothers without anti‐p40tax (54.5% versus 12.5%). Two men without anti‐p40tax and one female with low anti‐p40tax developed ATL during follow‐up studies. These results suggest that HTLV‐I carriers could be divided into 2 or 3 sub‐populations according to antibody response to p40tax. A smaller population with anti‐p40tax, especially a high antibody reactivity, could have a high risk of developing HAM and of transmission from mother to child. In addition, ATL may occur in a population with low or absent anti‐p40tax.
Effect of Human Interferons on Morphological Differentiation and Suppression of N‐myc Gene Expression in Human Neuroblastoma Cells
Authors: Watanabe Hisao , Chisaka Takeshi , Higuchi Takakazu , Tanaka Atsuo , Horii Yoshihiro , Sugimoto Tohru , Imanishi Jiro
Published: August 2005

The activity of human interferons (HuIFNs) to induce morphological changes and the suppression of N‐myc gene expression on human neuroblastoma cells (GOTO and KP‐N‐RT) was evaluated. Morphological differentiation, characterized as the extension and bifurcation of neurites, the formation of multinucleated giant cells and the formation of neurite networks, was induced by treatment with recombinant HuIFN‐γ (rHuIFN‐γ and also with natural HuIFN‐γ on human neuroblastoma cells (GOTO and KP‐N‐RT). But recombinant HuIFN‐αA and recombinant HuIFN‐βdid not induce any changes. The rHuIFN‐β and rHuIFN‐γ inhibited the growth of GOTO and KP‐N‐RT cells more strongly than the rHuIFN‐αA did. The expression of N‐myc gene was suppressed in GOTO cells treated with rHuIFN‐γ. The suppressive effect of rHuIFN‐γ was dependent on the duration of the treatment. However, rHuIFN‐αA and rHuIFN‐β did not suppress N‐myc gene expression. Moreover, both morphological differentiation and the supprcssive effect on N‐myc gene expression by rHuIFN‐γ were inhibited in the presence of cycloheximide. These results suggest that the morphological changes and N‐myc gene expression in neuroblastoma cells are closely related. Furthermore, this decreased N‐myc gene expression during the morphological differentiation may be related to the proteins induced by HuIFN‐γ.
Augmentation of Murine Lymphokine‐activated Killer Cell Induction by a Factor Produced by Nocardia rubra Cell Wall Skeleton‐stimulated T Cells
Authors: Kawase Ichiro , Shirasaka Takuma , Ikeda Toshiyuki , Hara Hideki , Tanio Yoshiro , Watanabe Masatoshi , Saito Shin'ichi , Masuno Tomiya , Kishimoto Susumu , Yamamura Yuichi
Published: August 2005

Four‐hour exposure of C3H/HeN mouse spleen cells to Nocardia rubra cell wall skeleton (N‐CWS) before 4‐day culture with a suboptimal dose of human recombinant interleukin 2 (rIL 2) augmented the induction of lymphokine‐activated killer (LAK) cell activity, whereas the treatment with N‐CWS alone induced no cytotoxicity. In accordance with this, the IL 2 binding activity of spleen cells was augmented by combined stimulation with N‐CWS and rIL 2. The augmented cytotoxicity was mediated by Thy‐1.2+, Lyt‐1.1−, Lyt‐2.1− and asialo GM1+ cells. Cell cultures in diffusion chambers revealed that N‐CWS‐treated spleen cells produced a LAK cell induction‐helper factor (LAK‐helper factor, LHF) when cultured with rIL 2. The LHF production required Thy‐1.2+, Lyt‐1.1+, Lyt‐2.1+ and asialo GM1− cells, and the coexistence of unstimulated accessory cells was also essential for the LHF production. Cells responding to both LHF and rIL 2 to generate LAK activity were Thy‐1.2−, Lyt‐1.1−, Lyt‐2.1− and asialo GM1+. The culture fluid of spleen cells stimulated with both N‐CWS and rIL 2 contained no tumor necrosis factor (TNF) activity, and the additional stimulation with N‐CWS caused no production of either IL 2 or interferon (IFN). Murine recombinant interleukin la (Mu‐rIL 1α) could not replace the augmentative effect of N‐CWS on LAK cell induction. These results suggest that in the presence of rIL 2, N‐CWS stimulates murine T cells to produce LHF that is probably distinct from IL 1, IL 2, TNF and IFN.
Modulation of Immune Response against Tumor Cells by the in vivo Administration of an Autoreactive Th Clone
Authors: Kubo Masato , Sano Kunio , Fujisawa Isao , Asano Yoshihiro , Tada Tomio
Published: August 2005

The immunization of C3H mice with irradiated syngeneic MM48 tumor cells induced specific tumor‐neutralizing cells (TNC). The TNC activity was mediated by the L3T4+, Ly‐2− T cell population, and the generation of TNC coincided with the appearance of delayed‐type hypersensitivity response against MM48 antigen. The administration of an auto‐I‐Ak reactive T helper cell clone MS202 to normal C3H mice resulted in the facilitation of growth of MM48 tumor due to the induction of T suppressor (Ts) cells. Splenic T cells from animals given this T cell clone inhibited the TNC activity of immunized mice resulting in the escape of MM48 from the TNC effect. The surface phenotype of the Ts cells was L3T4+, Ly‐2−. The Ts cells induced by the clone MS202 were totally antigen‐nonspecific, and were able to suppress both the effector and inductive processes of TNC. The results suggest the presence of a physiological MHC‐restricted T cell circuit that regulates immune responses against the growing tumors.
A New, Potent 2‐Nitroimidazole Nucleoside Hypoxic Cell Radiosensitizer, RP170
Authors: Sasai Keisuke , Shibamoto Yuta , Takahashi Masaji , Abe Mitsuyuki , Wang Jun , Zhou Lin , Nishimoto Sei‐ichi , Kagiya Tsutomu
Published: August 2005

The radiosensitizing activity, acute toxicity and pharmacokinetics of RP170, a new hypoxic cell radiosensitizer, were compared with those of misonidazole (MISO) and SR2S08. RP170 belongs to the group of 2‐nitroimidazole nucleosides, which are designed to be selectively excluded from the neural tissue. The reduction potential of RP170 was similar to that of MISO and SR2508. The partition coefficients in octanol/water of RP170, MISO, and SR2508 were 0.094, 0,35, and 0.021, respectively. The radiosensitizing activity of RP170 was similar to that of MISO and SR2508 in vitro and in vivo. There was no significant difference in the radiosensitizing activity of RP170 in vivo between intravenous and intraperitoneal administration. The acute toxicity of RP170 was the same as that of SR2508. Pharmacokinetic evaluation showed that the concentration of RP170 in the brain was as low as that of SR2508. RP170 is expected to have the same radiosensitizing effects as MISO and SR2S08, and to be less neurotoxic than MISO.
Active Specific Chemoimmunotherapy of Lymph‐node Metastasis from a Poorly Immunogenic Murine Fibrosarcoma
Authors: Naito Kazuyo , Oka Takahiro , Nomi Shinhachiro , Yamagishi Hisakazu , Kahan Barry D.
Published: August 2005

The fibrosarcoma MCA‐SP, which was recently induced with methylcholanthrene (MCA) in C3H/ HeJ mice, displays poor immunogenicity in in vivo prophylaxis. A cell variant MCA‐SPN1, which bears a tumor‐specific transplantation antigen (TSTA) cross‐reactive with the parental line MCA‐SP, was selected because of its proclivity for axillary lymph‐node metastases. Although these lymph‐node metastases were resistant to sinecomitant (post‐excisional) immunity, they were susceptible to combined active and passive specific Chemoimmunotherapy, using tumor‐specific, 1‐butanol‐extracted, preparative isoelectric focusing‐purified, TSTA (1 fig weekly sc injections), cyclophosphamide (CY, a single intraperitoneal 20 mg/kg dose), and adoptive transfer of immune splenic T lymphocytes, which had been re‐stimulated in vitro with extracted TSTA and interleukin‐2. This triple regimen both reduced the incidence of spontaneous lymph‐node metastases, and prolonged the survival of tumor‐bearing, as well as tumor‐resected hosts. The results from local adoptive transfer assay using T‐lymphocyte snbpopulations of spleen and lymph nodes in these treated hosts suggested that Lyt 2+ cytotoxic T‐lymphocytes (CTL) mediated in vivo tumor‐neutralization. Thus TSTA/CY/CTL therapy activates tumoricidal host responses effective against the poorly immunogenic MCA‐SP tumor and its lymph‐node metastases.
Production and Effect of Infectious Dane Particles in Transgenic Mice
Authors: Araki Kimi , Nishimura Shinichiro , Ochiya Takahiro , Okubo Kousaku , Miyazaki Jun‐ichi , Matsubara Kenichi , Yamamura Ken‐ichi
Published: August 2005

We have demonstrated by immunoelectron microscopy that 42‐nm particles with double‐shelled structures characteristic of Dane particles are present in the serum of transgenic mice, 1.2HB‐BS 10, carrying partly duplicated hepatitis B virus (HBV) genome. Furthermore, these particles were shown to infect primary human fetal hepatocytes as demonstrated by the elevation of MBV surface antigen (HBsAg) in the culture medium. HBV DNA is known to be expressed in a liver‐ and kidney‐specific manner in the adult mouse, so we examined the developmental expression of viral antigens. In the liver, viral antigens (HBsAg and HBV e antigen) began to be expressed before birth and the level of expression showed a sharp rise after birth. On the other hand, in the kidney, viral antigens began to be expressed after birth. Serum levels of viral antigens were roughly proportional to the levels of expression in the liver, suggesting that the liver is the main source for viral antigens in the serum. None of these transgenic mice produced anti‐HBs or anti‐HBV core response or showed biochemical or pathological change up to at least 24 months of age. All these results suggest that infectious viral particles can be produced in transgenic mice, and that expression and replication of HBV DNA are not toxic in vivo.
Verification of HTLV‐I Infection in the Solomon Islands by Virus Isolation and Gene Amplification
Authors: Yanagihara Richard , Ajdukiewicz Andrew B. , Nerurkar Vivek R. , Garruto Ralph M. , Gajdusek D. Carleton
Published: August 2005

We report the detection of human T‐lymphotropic virus type I (HTLV‐I) genomic sequences by polymerase chain reaction in lymphocyte cultures of three unrelated native Solomon Islanders, including a patient with HTLV‐I myeloneuropathy, residing in widely separated regions. In addition, we have isolated HTLV‐I from T‐cell lines derived from two of these individuals. Virus‐specific proteins of 15, 19, 24, 46 and 53 kilodaltons were detected by immunofluorescence and Western immunoblot, using serum from a Colombian patient with HTLV‐I myeloneuropathy, sera from HTLV‐I‐infected rabbits, and monoclonal and polyclonal antibodies against HTLV‐I gag and env gene products. Amplification of HTLV‐I gag, pol and env sequences by polymerase chain reaction confirmed that the viral isolates were HTLV‐I, not HTLV‐II. Our data clearly demonstrate that HTLV‐I does exist in Melanesia. Although the Solomon Islands viral isolates resemble prototype strains of HTLV‐I, we believe they represent variants of HTLV‐I, particularly in the light of our recent isolation of an HTLV‐I variant from Papua New Guinea. Nucleotide sequence analysis of these viral strains, now in progress, should clarify the molecular epidemiology and phylogeny of HTLV‐I.
Higher Frequency of Point Mutations in the c‐K‐ras2 Gene in Human Colorectal Adenomas with Severe Atypia than in Carcinomas
Authors: Ando Masayuki , Maruyama Michio , Oto Michiei , Takemura Katsuji , Endo Mitsuo , Yuasa Yasuhito
Published: August 2005

Human colorectal carcinomas may be induced from adenomas or they may occur de novo. To examine which is the main pathway, we analyzed point mutations at codon 12 in the c‐K‐ras 2 gene in 73 colorectal carcinomas, 13 metastatic tumors, 72 adenomas and 30 normal tissues. The c‐K‐ras 2 codon 12 mutation frequency was 0/30 in normal tissues, 0/17 in adenomas with mild atypia, 3/37 (8.1%) in adenomas with moderate atypia, 15/18 (83.3%) in adenomas with severe atypia, 19/73 (26.0%) in primary carcinomas and 3/13 (23.1%) in metastatic tumors. The mutation frequency in adenomas with severe atypia was much higher than that in carcinomas. These results indicate that many colorectal carcinomas may not be induced through adenomas with severe atypia.
Correlation between Physiological and Transforming Activities of the c–mos Proto–oncogene Product and Identification of an Essential Mos Domain for These Activities
Authors: Okazaki Kenji , Furuno Nobuaki , Watanabe Nobumoto , Ikawa Yoji , Vande Woude George F. , Sagata Noriyuki
Published: August 2005

Using Xenopus eggs and NIH3T3 cells as assay systems, we have compared the physiological (i.e. maturation–inducing and cleavage–arresting) and in vitro transforming activities of the c–mos genes from various species as well as their mutant genes. These analyses show that the three biological activities all depend upon the intrinsic protein kinase activity of Mos and correlate well with each other. Furthermore, our results demonstrate that a well conserved N–terminal 14–amino acid sequence of Mos, termed the Mos–hox, is essential for all three activities. These results indicate that the in vitro transforming activity of Mos can he ascribed to the same kinase activity of Mos that exerts the physiological activities.
Association between Restriction Fragment Length Polymorphism of the Human Cytochrome P450IIE1 Gene and Susceptibility to Lung Cancer
Authors: Uematsu Fumiyuki , Kikuchi Hideaki , Motomiya Masakichi , Abe Tatsuya , Sagami Ikuko , Ohmachi Tetsuo , Wakui Akira , Kanamaru Ryunosuke , Watanabe Minro
Published: August 2005

Cytochrome P450IIE1 (P450IIE1) is involved in metabolic activation of carcinogenic nitrosamines, aniline and benzene. We detected a restriction fragment length polymorphism of the human P450IIE1 gene with the restriction endonuclease Oral. The population was thus divided into three genotypes, namely, heterozygotes (CD) and two forms of homozygotes (CC and DD). The distribution of these genotypes among lung cancer patients differed front that among controls with statistical significance of P< 0.05 (x2=7.01 with 2 degrees of freedom). This result strongly suggests that host susceptibility to lung cancer is associated with the Dral polymorphism of the P450IIE1 gene.
Macrophage–T Cell Interaction Is Essential for the Induction of p75 Interleukin 2 (IL–2) Receptor and IL–2 Responsiveness in Human CD4+T Cells
Authors: Nakamura Yoshihiko , Nishimura Takashi , Tokuda Yutaka , Kobayashi Nobumasa , Watanabe Katsuto , Noto Takashi , Mitomi Toshio , Sugamura Kazuo , Habu Sonoko
Published: August 2005

Fresh human CD8+T cells showed a strong proliferative response to a high concentration of interleukin 2 (IL–2) in the absence of macrophages. In contrast, CD4+T cells revealed no significant IL–2 responsiveness in the absence of macrophages. However, if CD4+T cells were cocultured with macrophages, they showed higher proliferative response to IL–2 than CD8+T cells. In accordance with the magnitude of IL–2 responsiveness, freshly isolated CD8+T cells expressed significant amounts of p75 IL–2 receptor, while fresh CD4+T cells did not express p75 IL–2 receptor. The expression of p75 IL–2 receptor on CD4+T cells was induced by coculture with macrophages. The macrophage–induced p75 IL–2 receptor acquisition was blocked by monoclonal antibody (inAh) against class II antigen. Moreover, the addition of anti–CD4 mAb or anti–class II mAb to the culture caused a great inhibition of IL–2 responsiveness of CD4+T cells. These results strongly suggest that macrophage–T cell interaction through CD4 and/or class II moleculesisessential for the expression of p75 IL–2 receptor and IL–2 responsiveness in human CD4+, but not CD8+T cells.
Antigen‐presenting Cells Constitutively Bind Tumor Antigens in the Tumor‐bearing State in vivo to Construct an Effective Immunogenic Unit
Authors: Shimizu Jun , Zou Jian‐Ping , Ikegame Kazuhiro , Fujiwara Hiromi , Hamaoka Toshiyuki
Published: August 2005

Antigen‐presenting cells (APC) constitntively process endogenous (self) proteins to bind the processed peptides to la molecules. In the present study, we investigated whether the same associative recognition also holds true for tumor‐associated antigens (TAA) that are regarded as “self” molecules in tumor‐bearing hosts. The following results were obtained: (i) an APC‐depleted splenic T cell population from CSA1M tumor‐immunized hosts was stimulated to produce interleukin 2 in vitro when co‐cultured with APC from CSA1M‐bearing mice, but not from normal mice; and (ii) a Thy‐l+ cell‐depleted APC population from CSA1M‐bearing mice could produce CSA1M tumor‐specific protection in vivo when inoculated into naive syngeneic mice. These results provide evidence for the functional binding in vivo of TAA to APC in the tumor‐bearing state. The results are discussed in the context of the paradox that tumor‐bearers fail to reject their own malignancy despite the formation on APC of an effective immunogenic unit which is capable of stimulating tumor‐specific T cells.
Lung Cancer Risk among Exsmokers
Authors: Sobue Tomotaka , Suzuki Takaichiro , Fujimoto Isaburo , Matsuda Minoru , Doi Osamu , Mori Akashi , Furuse Kiyoyuki , Fukuoka Masahiro , Yasumitsu Tsutomu , Kuwahara Osamu , Ichitani Michio , Taki Toshihiko , Kuwabara Masayoshi , Nakahara Kazuya , Endo Shozo , Sawamura Kenji , Kurata Masahiko , Hattori Shoji
Published: August 2005

Lung cancer risk among exsmokers according to years since cessation of smoking was assessed by means of a case‐control study. The case series consisted of 1,052 lung cancer patients who were newly diagnosed and admitted to eight hospitals in Osaka in 1986–88. Smoking histories were compared with those of 1,111 controls admitted to the same hospitals during the same period without any diagnosis of smoking‐related disease. The odds ratio of lung cancer for exsmokers compared to current smokers was estimated to be 0.90, 0.50, 0.51, 0.59, 0.48 and 0.29, for 1–4, 5–9,10–14,15 19, 20 24 and ± 25 years after cessation of smoking, respectively. Risk reduction appeared to be greater for those who smoked less than the 1200 cigarette index, compared to those who smoked more. In classification according to histologic type, small cell and large cell carcinoma showed a rapid decrease compared to adenocarcinoma, while squamous cell carcinoma showed an intermediate pattern. Quantitative estimates for reduction of lung cancer risk among exsmokers can be used for projecting lung cancer incidence in the future, by assuming future trends of smoking prevalence, as well as for health education among individual smokers.
Protective Effect by Potassium Chloride against Gastric Carcinogenesis Induced by N‐Methyl‐N'‐nitro‐N‐nitrosoguanidine in Spontaneously Hypertensive Rats
Authors: Tatsuta Masaharu , Lishi Hiroyasu , Baba Miyako , Ichii Makoto , Nakaizumi Akihiko , Uehara Hiroyuki , Taniguchi Haruo
Published: August 2005

The effects of oral potassium supplementation on the enhanced induction of gastric carcinogenesis by N‐methyl‐N'‐nitro‐N‐nitrosoguanidine (MNNG) in spontaneously hypertensive rats (SHR), and the norepinephrine concentration in their gastric wall were investigated. The SHR and normotensive Wistar Kyoto rats (WKY) as controls were given a solution of the carcinogen for 25 weeks and then 1% KCl solution or tap water to drink. In Week 52, the incidence of gastric cancers and their number per rat and the norepinephrine concentration in the gastric wall were significantly greater in SHR than in WKY. Prolonged oral treatment of SHR with potassium significantly reduced the incidence of gastric cancers and their number per rat, as well as the blood pressure and the norepinephrine concentration in the antral portion of the gastric wall. These findings indicate that prolonged treatment with KCl attenuated the enhancement of gastric carcinogenesis by MNNG in SHR.
Trial to Induce Prostatic Cancer in ACI/Seg Rats Treated with a Combination of 3,2′‐Dimethyl‐4‐aminobiphenyl and Ethinyl Estradiol
Authors: Takai Kazuhiro , Kakizoe Tadao , Tanaka Yoshinori , Tobisu Ken‐ichi , Aso Yoshio
Published: August 2005

In an attempt to induce prostatic adenocarcinoma at higher incidence in a shorter period, we administered diet containing 0.75 ppm of ethinyl estradiol (EE) for three weeks to ACI/Seg rats, which are predisposed to develop a high incidence of microscopic adenocarcinoma of the prostate at higher age. Then, feeding was changed to basal diet and a single subcutaneous injection of 50 mg/kg body weight of 3,2′‐dimethyl‐4‐aminobiphenyl (DMAB) was given two days after the change. We repeated this schedule 10 times. The rats were killed in week 60 of the experiment and subjected to routine autopsy. The average body weight of rats in group 1 given EE and DMAB was lower than that of control rats in group 2. The incidence of adenocarcinoma was not significantly different in the two groups, i.e. 6/74 (8.1%) in group 1 and 2/54 (3.7%) in group 2. The lesions were all microscopic. The incidence of atypical hyperplasia was significantly higher in group 1 at 17 of 74 rats (23.0%) whereas in group 2, it was only 2 of 54 rats (3.7%). Simple hyperplasia was also observed in 25 of 74 rats (33.8%) in group 1, which was significantly higher than that in group 2, where six of 54 rats (11.1%) had this lesion. The reduced growth of animals due to treatments with EE and DMAB probably suppressed the development of prostate cancer in this experiment. Further studies are needed to develop an appropriate model to induce prostate carcinoma at higher incidence in a shorter period.
Age‐dependent Induction of Preneoplastic Liver Cell Foci by 2‐Acetylammo‐fluorene, Phenobarbital and Acetaminophen in F344 Rats Initially Treated with Diethylnitrosamine
Authors: Hasegawa Ryohei , Takahashi Satoru , Imaida Katsumi , Yamaguchi Shuji , Shirai Tomoyuki , Ito Nobuyuki
Published: August 2005

Effects of age on the induction of glutathione S‐transferase placental form (GST‐P)‐positive hepatic foci in rats were examined using a medium‐term liver bioassay system (for carcinogens). F344 male rats aged 6, 26 and 46 weeks were initially given a single intraperitoneal injection of diethylnitro‐samine (DEN, 200 mg/kg) and, beginning 2 weeks later, received 0.02% 2‐acetylaminofluorene (2‐AAF), 0.05% phenobarbital (PB) or 1.3% acetaminophen (AAP) in the diet for 6 weeks. All animals were subjected to two‐thirds hepatectomy 3 weeks after the DEN injection and were killed at week 8. Quantitative analysis of GST‐P‐positive foci revealed significantly (P< 0.001) increased induction over control levels in terms of both numbers and areas for 2‐AAF at all ages (6, 26 and 46 weeks), but especially in the 6‐week‐old case. In the PB‐ and AAP‐treated groups, the respective enhancing and inhibitory influences were most pronounced in the animals aged 6 weeks, and were less marked in older rats. Thus, the response of F344 rats to the modifying effects of chemicals was age‐dependent, the conclusion being drawn that young rats are more susceptible and therefore more appropriate for assessment of carcinogenic, promoting and inhibitory effects of chemicals.
Heterogeneity of Cloned Cell Lines Established from a Transplantable Rat Malignant Fibrous Histiocytoma
Authors: Yamate Jyoji , Tajima Masanori , Togo Masaharu , Shibuya Kazumoto , Ihara Miheko , Kudow Satoru
Published: August 2005

Four cloned cell lines, MT‐7, MT‐8, MT‐9 and MX‐10, were established from a transplantable malignant fibrous histiocytoma (MFH) of F344 rats to investigate the histogenesis of the tumor. Cells of MT‐7, MT‐9 and MT‐10 had fine structures characteristic of histiocytes, such as numerous cell processes, many lysosomes and well‐developed cytoplasmic organelles. They stained positively for histiocytic lysosomal and antigenic markers. In addition, MT‐9 cells contained microfllaments and well‐developed RER in their cytoplasm, suggesting that they may be facultative fibroblasts. MT‐8 cells stained weakly for histiocytic markers and had scant cytoplasmic organelles. They were identified as undifferentiated mesenchymal cells. The tumors induced in syngeneic rats by inoculating MT‐7 or MT‐10 consisted of a mixture of the pleomorphic, myxoid and storiform types of MFH, and those by MT‐9 were of the storiform type. Cells forming these tumors stained positively for histiocytic markers. Tumors induced by MT‐8 consisted of undifferentiated cells negative to these stainings. The histogenesis of MFH is surmised to be related to various differentiation stages shifting from undifferentiated cells to histiocytic cells capable of acting as facultative fibroblasts.
Purification of Ornithine Decarboxylase‐inducing Factor from Cell‐free Ascites Fluid of Ehrlich Ascites Tumor and Its Characteristics
Authors: Imamura Kiichi , Wang Ziyuang , Murayama‐Oda Kikuno , Kim Hee‐Kyoung , Tsuji Takao , Tanaka Takehiko
Published: August 2005

The ornithine decarboxylase‐inducing factor (ODC factor) was purified about 1,000‐fold in 42% yield from the ascites fluids of an Ehrlich ascites tumor by a combination of centrifugation and concanavalin A (ConA) treatment. A single ip injection of 0.5μg of the purified factor per mouse resulted in half‐maximum induction of liver ODC. The factor was found to be a trypsin‐ and chymotrypsin‐resistant, acidic glycoprotein (pi about 4.43) with a minimum molecular weight of about 70 kilodaltons, containing a disulfide bond(s) in its functional domain. It did not react with ConA. This factor induced retrodifferentiation of liver function, causing a marked increase of prototype M2 isozyme of pyruvate kinase. It reduced liver catalase activity, and also modified thyroid hormone metabolism, reducing the serum levels of T4 and T3. These results suggest that the ODC factor is multifunctional and induces many of the changes observed in a tumor‐bearing host.
Characterization and Purification of an Immunosuppressive Factor Produced by a Small Cell Lung Cancer Cell Line
Authors: Ikeda Toshiyuki , Masuno Tomiya , Ogura Takeshi , Watanabe Masatoshi , Shirasaka Takuma , Kara Hideki , Tanio Yoshiro , Kawase Ichiro , Kishimoto Susumu
Published: August 2005

The present study was undertaken to determine whether small cell lung cancer (SCLC) cell lines produce immunosuppressive factors and, if they do, to characterize the factors. The supernatants of SCLG cell lines, H69 and N857, inhibited not only the blastogenic response of human peripheral blood lymphocytes (PBL) to phytohemagglutinin or concanavalin A, but also the cytotoxic activity of lymphokine‐activated killer cells. Neither was inhibited by supernatants from non‐SCLC cell lines PC9, QG56, and A549. The immunosuppressive activity of H69 supernatant was stable upon heating to 56°C for 60 min, but labile when heated to 70°C for 10 min. The activity was abolished after dialysis at pH 2.0 or pH 11.0, but not at pH 4.5 or pH 9.0. Digestion with trypsin or proteinase eliminated the immunosuppressive activity, whereas treatment with neuraminidase, mixed glycosidase, DNase or RNase had no effect, suggesting that the immunosuppressive activity in H69 supernatant is due to a protein factor. This H69‐derived immunosuppressive factor was isolated by ion exchange chromatography using a gradient of 0.04 to 0.08 M NaCl solution. Gel filtration and sodium dodecyl sulfate‐polyacrylamide gel electrophoresis showed the factor to have molecular weights of 98 kD and 102 kD, respectively. These results suggest that SCLC cells produce a potent immunosuppressive factor which may account for the immune deficiency in SCLC patients.
Cytological Characteristics of Human Glioma‐infiltrating Lymphocytes Stimulated with Recombinant Interleukin 2 and an Anti‐CD3 Antibody
Authors: Kikuchi Teturo , Watanabe Michiko , Ohno Tsuneya
Published: August 2005

Tumor‐infiltrating lymphocytes (TIL) were generated from 10 glioma specimens by using recombinant interleukin‐2 and an anti‐CD3 antibody (CD3 + TILs). We obtained more than 1 × 108 cells in 5 cases, more than 5 × 108 cells in 2 cases, and about 1 × 108 cells in 3 cases during three weeks of incubation from small specimens ranging in weight from 0.5 to 2.0 g. In 4 cases, TILs were expanded following stimulation with only rIL‐2 (CD3‐TILs). The growth rate of CD3‐TILs was less than that of CD3 + TILs. Cytotoxicity of CD3+TILs was lower than that of lymphokine‐activated killer (LAK) cells in a standard 4h 51Cr release assay. Cold target inhibition was undertaken in three cases and specific cytotoxicity could be shown in only one case. CD3 + TILs mainly consisted of CDS‐positive cells, ranging from 63.2 to 99.9%. The ratio of CD4‐positive cells to CDS‐positive cells was not constant. The expression of Leu 7 and CD16 was low. The present study did not confirm previous findings that TILs were more tumor‐selective and potent than LAK cells. Furthermore, the results on in vitro antitumor activity of those cells were not necessarily consistent with the results on their clinical activity. Further careful work is necessary on the preparation of immunocytes and the subsequent adoptive immunotherapy.
Effect of Co‐administration of Granulocyte Colony‐stimulating Factor on Interferon Therapy
Authors: Segawa Kotaro , Suhara Yasuji , Ueno Yoshio , Kataoka Tateshi
Published: August 2005

The effect of co‐administration of granulocyte colony‐stimulating factor (G‐CSF), as an anti‐neutropenia agent, on interferon therapy was examined in a mouse model, in anticipation of an enhancement of interferon efficacy, because neutrophils induced by G‐CSF are thought to act as antitumor effectors. G‐CSF was intraperitoneally co‐administered with human interferon α A/D (IFN) on Day 6 to Day 10 after intradermal inoculation of Meth A fibrosarcoma. Although the co‐administration of G‐CSF could protect against neutropenia and leukopenia induced by IFN, it did not enhance the regression of tumor, and rather reduced the prolongation of survival time and the long‐term survival incidence of IFN therapy. The subsequent in vitro study showed that the antiproliferative activity of peripheral blood leukocytes from Meth A‐bearing mice given both IFN and G‐CSF was much weaker than that of mice given IFN alone. Whether the observed nullifying effect of G‐CSF on IFN therapy is also the case with tumors other than Meth A is open to further study.
Proliferative Activity of Human Tumors: Assessment Using Bromodeoxyuridine and Flow Cytometry
Authors: Shimomatsuya Takumi , Tanigawa Nobuhiko , Muraoka Ryusuke
Published: August 2005

Cell kinetics of human carcinoma xenografts and human solid tumors were evaluated by means of two‐color flow cytometry using single sampling at appropriate time intervals after bromodeoxyuridine (BrdU) labeling. The tumors were resected several hours after the administration of BrdU, and flow cytometry was used to measure the DNA content and BrdU incorporation. Once the BrdU labeling index (LI) and DNA synthesis time (Ts) were obtained, the potential doubling time (Tpot) was calculated from these values. In 11 xenografts, the cell kinetic data were compared with the actual tumor doubling time (Td), and a good correlation between Tpot and Td was obtained (r=0.91, P< 0.005). In a clinical study, 33 patients with gastric cancer, colorectal cancer, lung cancer, or other solid tumors were analyzed. Aneuploid tumors had a significantly higher LI value (P< 0.01) and a shorter Tpot than diploid tumors. The cell loss rate of human tumors ranged from 40% to 80%. These cell kinetic parameters therefore accurately indicated the level of proliferative activity of human tumors.
Okadaic Acid Is a Potent Angiogenesis Inducer
Authors: Oikawa Tsutomu , Suganuma Masami , Ashino‐Fuse Hiromi , Shimamura Mariko
Published: August 2005

Okadaic acid, which is a non‐12‐0‐tetradecanoylphorbol‐13‐acetate (TPA)‐type tumor promoter and an inhibitor of protein phosphatases 1 and 2A, induced angiogenesis in the chorioallantoic membrane of the chick embryo. Its potent angiogenic activity was dose‐dependent. The minimum effective dose was 5 fmol/egg and the effective dose for 50% induction was 90 fmol/egg. These results indicated that okadaic acid exhibits angiogenic activity one order of magnitude stronger than that of TPA (reported previously). Moreover, the time‐course of angiogenesis induction by okadaic acid was much slower than that by TPA. The difference is consistent with the time‐courses of other biochemical and biological activities and also various gene expressions induced by okadaic acid and TPA, indicating that the difference in the time‐course is associated with their mechanisms of action. We conclude that okadaic acid induces angiogenesis through a different pathway than does TPA, indicating the existence of a new mechanism of angiogenesis induction.
Use of a Local Immunotherapy as an Adjunctive Tool for the Generation of Human Monoclonal Antibodies from Regional Lymph Nodes of Colonic Cancer Patients
Authors: Yagyu Toshio , Monden Takushi , Tamaki Yasuhiro , Morimoto Hideki , Takeda Tsutomu , Kobayashi Tetsuro , Shimano Takashi , Murakami Hiroki , Mori Takesada
Published: August 2005

Human hybridomas were generated through the fusion of the human B‐lymphoblastoid cell line HO‐323 with the regional lymph node lymphocytes of colonic cancer patients who had received a local immunotherapy. A total of 353 hybridomas were obtained from 4 patients and 116 of these were found to secrete ≧ 100 ng/ml human immunoglobulin. The efficiency was remarkably high as compared with that from patients without the local immunotherapy. Further immunohistological examination showed that 5 hybridomas secreted IgM which selectively reacted with colonic cancers. The results indicate that local immunotherapy could be an adjunctive tool for the generation of highly potent human hybridomas through augmenting the host's immunity.
The Modifying Effects of Indomethacin or Ascorbic Acid on Cell Proliferation Induced by Different Types of Bladder Tumor Promoters in Rat Urinary Bladder and Forestomach Mucosal Epithelium
Authors: Shibata Masa‐Aki , Fukushima Shoji , Asakawa Emiko , Hirose Masao , Ito Nobuyuki
Published: August 2005

The effects of indomethacin (IM) or L‐ascorbic acid (AsA) on cell proliferation induced by bladder tumor promoters such as butylated hydroxyanisole (BHA), sodium L‐ascorbate (Na‐AsA), sodium citrate (Na‐Cit), and diphenyl (DP) in rat bladder and forestomach epithelium were investigated. Treatment with IM in combination with BHA or Na‐AsA diminished DNA synthesis levels of bladder epithelium as compared to the BHA or Na‐AsA alone values. On the other hand, AsA further amplified the increase of bladder epithelial DNA synthesis caused by Na‐Cit treatment. Histopathologically, administration of Na‐AsA in combination with IM reduced the incidence of simple hyperplasia. In contrast, simultaneous treatment with Na‐Cit and AsA caused an increase of the hyperplasia development. No apparent combination effects were observed in the DP‐treated groups. In forestomach epithelium, AsA enhanced the BHA‐induced increase in DNA synthesis and epithelial hyperplasia, characterized by marked basal cell proliferation. The present results thus suggested that IM may exert inhibitory effects on promotion of bladder carcinogenesis by certain tumor promoter types, and AsA may enhance BHA forestomach carcinogenesis.
Modifying Effects of Soybean Trypsin Inhibitor on Development of Eosinophilic Nodules and Basophilic Foci in the Exocrine Pancreas of Male Sprague‐Dawley Rats Treated with 4‐Hydroxyaminoquinoline 1‐Oxide
Authors: Furukawa Fumio , Imaida Katsumi , Imazawa Takayoshi , Hayashi Yuzo , Takahashi Michihito
Published: August 2005

Administration of 4‐liydroxyaniinoquiiioline 1‐oxide (HAQO) to rats results in development of 2 types of pancreatic acinar lesions, namely eosinophilic nodules and basophilic foci. To cast light on the biological character of these lesions, 5‐week‐old male Sprague‐Dawley rats were given a single intravenous injection of HAQO at a dose of 7 mg/kg and, thereafter, fed soybean trypsin inhibitor (SBTI) at dose levels of 10% and 5%. At week 57, all rats were killed for pathological examination of pancreatic tissue. The incidence of eosinophilic nodules was significantly higher in the HAQO/ SBTI group than in the HAQO‐alone group, whereas the basophilic acinar foci were observed to occur less frequently and to be smaller in the HAQO/SBTI‐treated animals. Administration of SBTI is known to increase the blood level of cholecystokinin, a trophic factor for pancreatic acinar cells. Thus, the present findings suggest that long‐term elevation of this endocrine factor can affect the two types of pancreatic acinar lesions in essentially different ways, namely enhancing development of eosinophilic nodules, while suppressing the occurrence of basophilic foci.
The Protective Role of Glutathione, Cysteine and Vitamin C against Oxidative DNA Damage Induced in Rat Kidney by Potassium Bromate
Authors: Sai Kimie , Umemura Takashi , Takagi Atsuya , Hasegawa Ryuichi , Kurokawa Yuji
Published: August 2005

The roles of glutathione (GSH), cysteine, vitamin C., liposome‐encapsulated superoxide dismutase (L‐SOD) and vitamin E in preventing oxidative DNA damage and cytotoxicity in the rat kidney after administration of potassium bromate (KBrO3) to male F344 rats were investigated by measuring 8‐hydroxydeoxyguanosine (8‐OH‐dG), an oxidative DNA product, lipid peroxidation (LPO) levels and relative kidney weight (RKW). Combined pre‐ and posttreatment of animals with 2 × 800 mg/kg GSH i.p. inhibited the increase of 8‐OH‐dG, LPO levels and RKW caused by 80 mg/kg KBrO3 i.p. administration. In contrast, pretreatment with 0.3 ml/kg diethylmaleate (DEM) i.p., a depletor of tissue GSH, was associated with elevation of 8‐OH‐dG, LPO levels and RKW after a 20 mg/kg KBrO3 i.p. treatment, which itself caused no change. Administration of KBrO3 itself reduced renal non‐protein thiol levels, but this was inhibited by the two doses of exogenous GSH. Combined treatment with DEM and KBrO3 lowered the non‐protein thiol level in the kidney more than did DEM treatment alone. Protective effects against the oxidative damage caused by KBrO3 were also observed for pre‐ and posttreatment with 400 mg/kg cysteine i.p., another sulfhydryl compound, and daily i.g. application of 200 mg/kg vitamin C for 5 days. However, no influence was evident after pre‐ and posttreatment with 18,000 U/kg L‐SOD i.p. or daily i.g. 100 mg/kg of vitamin E for 5 days. The results suggest that intracellular GSH plays an essential protective role against renal oxidative DNA damage and nephrotoxicity caused by KBrO3.
mRNA Levels of Catalytic Subunits of Protein Phosphatases 1, 2A, and 2C in Hepatocarcinogenesis
Authors: Kitamura Kazuki , Mizuno Yusuke , Hatayama Ichiro , Sato Kiyomi , Tamura Shinri , Nagao Minako , Tsuiki Shigeru , Kikuchi Kunimi
Published: August 2005

The mRNA levels of three phosphoseryl/phosphothreonyl protein phosphatases, PP1, PP2A and PP2C, in rat liver have been determined by Northern blot analysis in various stages of rat chemical hepatocarcinogenesis using a Solt‐Farber model. Five weeks after administration of diethyl‐nitrosamine, the mRNA levels of PPlα, PP2A and PP2C were elevated 8, 29 and 11 times, respectively, as compared to those of the control livers. However, in primary hepatoma induced according to the Solt‐Farber model, the mRNA levels of all three protein phosphatases were dramatically decreased to normal levels or even to much lower levels, whereas the mRNA level of glutathione S‐transferase placental form, a tumor marker protein, was greatly elevated as compared with that of the control livers. In a poorly differentiated hepatoma AH13, a line of rat ascites hepatoma, the mRNA level of PP1α was 5.6 times higher than that of the control livers, whereas the mRNA level of PP2C was almost the same as that of the control livers and the level of PP2A mRNA was distinctly lower than that of the control livers. These data appear to suggest some involvement of protein phosphatases in hepatocarcinogenesis.
Immunological Detection and Quantitation of DNA Adducts Formed by 4‐Aminoazobenzene Species in vivo
Authors: Kojima Misaki , Morita Toshiteru , Shirai Tomoyuki , Degawa Masakuni , Tada Mariko
Published: August 2005

Antibodies to 3‐methoxy‐4‐aminoazobenzene (3‐MeO‐AAB) and 2‐methoxy‐4‐aminoazobenzene (2‐MeO‐AAB) DNA adducts were raised in rabbits against in vitro‐adducted DNA samples. The enzyme‐linked immunosorbent assay (ELISA) was used to determine the sensitivity and specificity of these antibodies. They proved highly specific for the modified DNA used as the immunogen, but cross‐reacted with each other. Moreover, they showed cross reactivity with DNA modified by 4‐(o‐tolylazo)‐o‐toluidine, but not by other carcinogens, such as 4‐aminobiphenyl or 4‐nitroquinoline 1‐oxide. The 50% inhibition level of antibody binding in the competitive ELISA was at 10–20 fmol of modified base per assay (equivalent to 1–2 adducts per 106 bases). Immunohistochemical staining indicated that these antibodies bind specifically to nuclear components of the liver in rats given either 3‐MeO‐AAB or 2‐MeO‐AAB at the dose of 50 mg/kg body weight.
Clinicopathological Significance of Nuclear Accumulation of Tumor Suppressor Gene p53 Product in Primary Lung Cancer
Authors: Hiyoshi Haruhisa , Matsuno Yoshihiro , Kato Harubumi , Shimosato Yukio , Hirohashi Setsuo
Published: August 2005

Since the nuclear accumulation of p53 protein is known to correspond well with mutation of the p53 tumor suppressor gene, the authors examined 88 primary lung cancer specimens immunohistochemically using anti‐p53 mouse monoclonal antibody, pAb1801, and analyzed the relationship between the immunohistochemical results and clinicopathological features. Nuclear localization of p53 protein was found in 43/88 (49%) tumor specimens, but not in the corresponding normal lung tissues. The percentage of cases showing nuclear p53 localization varied according to the histological type. In squamous cell carcinoma, nuclear p53 localization was found in 15/26 (57%), appearing more frequently than in other histologic types. However, no obvious correlation was observed between nuclear p53 localization and patients’ age, sex, history of smoking, TNM factor, degree of differentiation, or any other clinicopathological features analyzed. In adenocarcinoma, nuclear p53 localization was found in 20/46 (43%). Incidence of positive cases was significantly correlated with regional lymph node metastasis, distant metastasis, and pathological stage (P < 0.05). These results indicate that mutation of the p53 tumor suppressor gene plays an important role in the development of primary lung cancer, and that nuclear accumulation of p53 protein is a potential prognostic factor in adenocarcinoma of the lung.
Expression of 85‐kDa Protein of Adriamycin‐resistant Tumor Cells during Hematopoietic Differentiation of THP‐1 and HEL Cells
Authors: Ishii Shigetaka , Naito Mikihiko , Masuda Miho , Tsuruo Takashi
Published: August 2005

An 85‐kDa protein was identified in adriamycin‐resistant tumor cells recognized by monoclonal antibody MRK‐20. Recently, the monoclonal antibody MRK‐20 was found to be reactive to human peripheral mononuclear cells. In order to investigate the molecular function of the 85‐kDa protein, we carried out flow cytometric analysis of the expression of the 85‐kDa protein during monocytic differentiation of the hematopoietic cells. Human myelomonocytic leukemia THP‐1 cells were induced to differentiate into macrophage‐like cells by treatment with 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA), A maximum of 55% of the cells expressed the 85‐kDa protein along with the CD‐14 antigen, which is a surface marker of monocytes and macrophages. The kinetic analysis revealed that the 85‐kDa protein appeared prior to the expression of the CD‐14 antigen. The 85‐kDa protein was also coexpressed with CD‐14 in THP‐1 cells that were induced to differentiate by recombinant tumor necrosis factor‐a, which is one of the physiological inducers of monocytic differentiation. In human erythroleukemia, HEL cells, the 85‐kDa protein was constitutively coexpressed with CD‐14. The expression of both the 85‐kDa protein and CD‐14 was drastically reduced during the megakaryocytic differentiation of the HEL cells with TPA. These results suggest that the 85‐kDa protein could be expressed on monocytic cells as well as CD‐14 and that the expression of the 85‐kDa protein might be regulated at an earlier stage of monocytic differentiation of hematopoietic cells than the expression of CD‐14.
Anticellular and Antitumor Activity of Duocarmycins, Novel Antitumor Antibiotics
Authors: Gomi Katsushige , Kobayashi Eiji , Miyoshi Katsunori , Ashizawa Tadashi , Okamoto Akihiko , Ogawa Tatsuhiro , Katsumata Shigeo , Mihara Akira , Okabe Masami , Hirata Tadashi
Published: August 2005

The anticellular and antitumor activities of novel antitumor antibiotics, duocarmycins (DUMs), were examined against human and murine tumor cells. DUMs consist of live compounds, A, B1, B2, C1, and C2, which possess a pharmacophore similar to that of CC‐1065, a previously isolated antibiotic. Among them, DUMA exhibited ultrapotent growth‐inhibitory activity with an IC50value of 6 pMagainst human uterine cervix carcinoma HeLa S3cells. DUMA and DUMB1 also inhibited the growth of adriamycin (ADM)‐resistant lines of human nasopharynx carcinoma KB cells and breast carcinoma MCF‐7 cells as well as their sensitive lines. DUMs inhibited the growth of s.c.‐inoculated murine tumors such as B16 melanoma, sarcoma 180, M5076 sarcoma and colon 26. DUMs were also significantly effective in increasing the lifespan of i.p.‐inoculated B16 melanoma‐bearing mice, although their effect was marginal against other i.p.‐inoculated tumors. As a whole, DUMB1 exhibited superior activity to the other four compounds. DUMB1 rapidly inhibited the incorporation of [3H]‐TdR into macromolecules of HeLa S3cells as compared with that of [3H]UR or [3H]leucine. DNA strand breaks were detected in DUMB1 ‐treated HeLa S3cells by agarose gel electrophoresis with a contour‐clamped homogeneous electric field apparatus. These results indicate that DUMs possess interesting biological activities as DNA‐targeting antitumor antibiotics.
Modulation of Membrane Permeability, Cell Proliferation and Cytotoxicity of Antitumor Agents by External ATP in Mouse Tumor Cells
Authors: Mure Tsutomu , Sano Kaiso , Kitagawa Takayuki
Published: August 2005

External ATP causes a remarkable change in the passive permeability of the plasma membrane in several types of transformed cells. When mouse melanoma cells, Clone‐M3, were exposed to ATP in Tris‐buffered saline, a great increase in the passive permeability was induced within several minutes. Longer exposure of Clone‐M3 cells to external ATP led to a decrease in cell viability. Similar results were obtained with Ehrlich ascites cells, but none of these ATP effects were noted in untransformed cells such as NIH 3T3 cells or BALB/c mouse embryonic fibroblasts. The in vitro cytotoxic effects of antitumor agents (5‐fluorouracil, adriamycin, mitomicin C and nimustine hydrochloride) against Clone‐M3 cells were additively potentiated by treatment with external ATP, which also synergistically enhanced the cytotoxicity of vincristine. However, the effects of these drugs on mouse embryonic fibroblasts were not modulated by ATP. These results suggest that ATP‐treatment is a useful means of enhancing a selective toxicity for tumor cells.