bluuebunny/crossref_metadata_2025 huggingface dataset:
Potentiation of Some Anticancer Agents by Dipyridamole against Drug‐sensitive and Drug‐resistant Cancer Cell Lines
Authors: Asoh Kuni‐ichi , Saburi Yoshio , Sato Shin‐ichi , Nogae Ichiro , Kohno Kimitoshi , Kuwano Michihiko
Published: August 2005

In this study, we have used two different vincristine (VCR)‐resistant variants, VJ‐300 and HC‐7–5/VCR. VJ‐300 was isolated from a human cancer KB cell line and HC‐7–5/VCR from a human cancer HC‐7–5 cell line. VJ‐300 and HC‐7–5/VCR are both multidrug‐resistant (MDR) variants, showing resistance to multiple anticancer drugs such as VCR, adriamycin, actinomycin D and daunomycin. Dipyridamole, a specific inhibitor of nucleoside transport, potentiated these anticancer drugs about 2‐ to 10‐fold against KB and VJ‐300. Dipyridamole almost completely reversed drug resistance to actinomycin D in VJ‐300 cells with about a 70‐fold higher resistance to actinomycin D. Dipyridamole inhibited the efflux of actinomycin D and VCR from VJ‐300 cells. Dipyridamole enhanced the uptake of VCR but not that of actinomycin D in VJ‐300 and KB. Dipyridamole at 10–100 μM inhibited photoaffinity labeling with [3H]azidopine of the cell‐surface protein P‐glycoprotein in VJ‐300 cells. Dipyridamole potentiated 5‐fluorouracil and hexylcarbamoyl‐5‐fluorouracil in cultured KB and VJ‐300, but it annihilated the cytotoxic action of 5‐fluorouridine. Potentiation of 5‐fluorouracil by dipyridamole against HC‐7–5 and HC‐7–5/VCR was also observed, but appeared to be less than in VJ‐300 and KB cells. Dipyridamole almost completely inhibited the cellular accumulation of 5‐fluorouridine, but not that of 5‐fluorouracil. Thus, dipyridamole appeared to potentiate anticancer agents through pleiotropic action sites, one of which is inhibition of enhanced efflux of MDR cell lines and the other of which is inhibition of nucleoside transport. Dipyridamole might be a useful and potent agent to potentiate anticancer agents and reverse drug‐resistance.
Potentiation of Growth‐inhibitory Activity of 9‐β‐d‐Arabinofuranosyladenine by 2′‐Deoxycoformycin in Human Cultured Cell Lines Derived from Leukemias and Lymphomas
Authors: Kuroki Yasumasa , Shimoyama Masanori , Inaba Satoshi , Hirose Masao
Published: August 2005

Growth‐inhibitory activity of 2′‐deoxycoformycin (DCF) and 9‐β‐D‐arabinofuranosyladenine (Ara‐A) used either singly or in combination was assessed in 30 human cultured cell lines (seven T‐cell, nine B‐cell, five non‐T, non‐B, and nine myeloid cell lines) derived from leukemias and lymphomas. DCF had little activity even at 100 μM any of the cell lines, while Ara‐A had an obvious inhibitory effect on them, especially on non‐T, non‐B cell lines at 10 μM or less. Lymphoid cell lines were apparently more sensitive to the combined use of Ara‐A and DCF than myeloid cell lines. DCF potentiated the antiproliferative activity of Ara‐A not only in T‐cell lines with high adenosine deaminase (ADA) activity, but also in some other cell lines with low ADA activity. DCF was stable in the culture medium, but Ara‐A in the medium containing cultured cells was rapidly inactivated. DCF completely inhibited the inactivation of Ara‐A in the medium containing P12/ICH or NALM‐6, but not in the medium containing Daudi. This suggests that there is some unknown mechanism(s) of inactivation of Ara‐A other than ADA in Daudi, which was insensitive to Ara‐A in the presence of 1 μM DCF. The capacity of DCF to inhibit degradation of Ara‐A in the medium containing these cultured cells correlated with the level of Ara‐A sensitivity potentiated by DCF. In all seven T‐cell lines, seven of the nine B‐cell lines, all five non‐T, non‐B cell lines, and only three of nine myeloid cell lines, the IC50 value for Ara‐A decreased to 5 μM or less in the presence of 1 μM DCF. These results suggest that the combination of DCF and Ara‐A may be effective against various types of lymphoid malignancies and some myeloid leukemias.
Point Mutations of c‐ras Genes in Human Bladder Cancer and Kidney Cancer
Authors: Nagata Yasuhiko , Abe Masumi , Kobayashi Kohmei , Saiki Shigeru , Kotake Toshihiko , Yoshikawa Kazuhiro , Ueda Ryuzo , Nakayama Eiichi , Shiku Hiroshi
Published: August 2005

Point mutations of c‐ras genes at codons 12, 13 and 61 were analyzed in 26 cases of bladder cancer and 16 cases of kidney cancer. DNA prepared from either frozen tissues or 10% formalin‐fixed, paraffin‐embedded tissues were amplified by means of polymerase chain reaction methods, and mutations were analyzed by dot blot hybridization assays with oligonucleotide probes. In three cases of bladder cancer c‐ras mutations were found, at codons 13 and 61 of c‐Ha‐ras and at codon 61 of c‐Ki‐ras, while no mutation was found in kidney cancer. No mutation was found in normal bladder epithelial tissues from the same patients. Our findings, taken together, may indicate relative scarcity of c‐ras mutations in these types of human cancer. The results of dot blot hybridization assays and DNA sequencing showed a G‐to‐C transition of the first nucleotide at codon 13 of c‐Ha‐ras. This is the first time that such a point mutation has been detected in human cancer tissues.
Philadelphia Chromosome‐positive Chronic Myelogenous Leukemia with Deleted Fusion of BCR and ABL Genes
Authors: Ohyashiki Kazuma , Ohyashiki Junko H. , Iwabuchi Hirotaka , Tauchi Tetsuzo , Iwabuchi Atsuhiro , Toyama Keisuke
Published: August 2005

In the great majority of patients with chronic myelogenous leukemia (CML) the reciprocal translocation between chromosomes 9 and 22, t(9;22)(q34;q11), resulting in the Philadelphia (Ph) chromosome produces fusion DNA sequences consisting of the 5′ part of the major breakpoint cluster region‐1 (M‐BCR‐1) and the ABL protooncogene which encodes for the P210BCR‐ABL phosphoprotein with tyrosine kinase activity implicated in the pathogenesis of CML. Molecular analysis was performed on 25 patients with Ph‐positive CML using 2 breakpoint cluster region (bcr) probes within the M‐BCR‐1 DNA sequences, and two of them did not contain either detectable rearranged DNA homologous to the 5′ side bcr probe or ABL‐related fusion mRNA. The chromosomal in situ hybridization technique revealed that these two Ph‐positive CML cases did not carry DNAs homologous to the 5′bcr or ABL probes on the Ph chromosome. Furthermore, one of the two Ph‐positive CML cases did not show either rearranged DNA or regions homologous to the 3′bcr probe on a 9q+ chromosome, while the other CML case showed a rearrangement detected by the 3′bcr probe and transposition of the 3′bcr homologous to the 9q+ chromosome. Thus, the possibility is raised that the BCR/ABL fusion DNA has been deleted in rare CML cases, and that the deletion possibly occurred in a stepwise manner following the formation of the Ph chromosome at any stage of the disease.
Identification of a Protein Increasing in Serum of Nagase Analbuminemic Rats Bearing Intestinal Tumors as an Isotype of T‐Kininogen
Authors: Kanda Shinji , Sugiyama Kenji , Takahashi Masakazu , Shumiya Seigo , Tomino Shiro , Nagase Sumi
Published: August 2005

Increase in an unidentified protein was observed in serum of Nagase analbuminemic rats (NAR) bearing intestinal tumors induced by azoxymethane. This protein seemed to be a polymer of a protein of 73 kDa as estimated by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, and so was tentatively named 73K‐protein. The serum concentration of 73K‐protein in NAR bearing intestinal tumors was 11.9 ± 2.2 mg/ml (mean ± SD, n = 5), whereas that in control NAR was 2.0 ± 0.2 mg/ml. Increase of the serum 73K‐protein level was also observed in Sprague‐Dawley rats bearing intestinal tumors, skin tumors, subcutaneous sarcomas, or mammary tumors and in ACI rats bearing urinary bladder tumors. On double immunodiffusion analysis, the 73K‐protein was not detected in mouse, guinea pig, pig, horse, or human serum. A cDNA clone bearing the sequence encoding 73K‐protein was isolated from a cDNA library constructed from rat liver mRNA. The nucleotide sequence of the 73K‐protein showed 98.8% and 96.9% homologies with the sequences of the 3′‐proximal domains of the cDNAs for TI‐ and TII‐kininogen, respectively. Therefore, the 73K‐protein was concluded to be an isotype of T‐kininogen.
Kinetics of Internalization and Cytotoxicity of Transferrin‐Neocarzinostatin Conjugate in Human Leukemia Cell Line, K562
Authors: Kohgo Yutaka , Kondo Hitoshi , Kato Junji , Sasaki Katsunori , Tsushima Nobuyasu , Nishisato Takuji , Hirayama Michiaki , Fujikawa Koshi , Shintani Naoaki , Mogi Yoshihiro , Niitsu Yoshiro
Published: August 2005

Human serum transferrin was conjugated with an anticancer‐active polypeptide, neocarzinostatin, by using N‐succinimidy1‐3‐(2‐pyridyldithio)propionate. The conjugate consisted of 1.8 mol of neocarzinostatin per 1 mol of transferrin on average and retained cytotoxic activity against human tumor cells. This conjugate was capable of binding to the transferrin receptor of human myelogenous leukemia K562 cells and was internalized by endocytosis. The LD50 values of the conjugate and neocarzinostatin alone in the presence of excess native bovine transferrin were 0.20 μ/ml and 1.80 μ/ml, respectively, suggesting that the effect of the conjugate was greater than that of neocarzinostatin alone. A pulse‐chase experiment using 125I‐labeled conjugate revealed that 25% of the internalized conjugate was degraded in lysosomes and the rest was recycled back to the cell surface without degradation. About 75% of this conjugate recycled back to the cell surface in 18.3 min (3.4 min for receptor binding and 14.9 min for recycling to the cell surface through the acidosomes), while the rest was delivered from the cell surface to the lysosome in 19.6 min. This phenomenon was confirmed by chasing the radioactivity in subcellular fractions separated by Percoll density gradient centrifugation. Therefore, it was concluded that this conjugate is internalized specifically by transferrin receptors and is at least partly transferred to and accumulated in lysosomal compartments, resulting in the inhibition of cellular DNA synthesis.
Normal Human Chromosome 1 Carries Suppressor Activity for Various Phenotypes of a Kirsten Murine Sarcoma Virus‐transformed NIH/3T3 Cell Line
Authors: Yamada Hideto , Horikawa Izumi , Hashiba Hiroki , Oshimura Mitsuo
Published: August 2005

In order to identify chromosomes that carry putative tumor‐suppressor genes for the various phenotypes of Kirsten sarcoma virus‐transformed NIH/3T3 (DT) cells, we performed microcell‐mediated chromosome transfer into DT cells. We first isolated mouse A9 clones, containing a single human chromosome 1, 11 or 12 tagged with pSV2‐neo plasmid DNA. Then, chromosome 1, 11 or 12 was transferred from the A9 clones into DT cells by microcell fusion. The growth rate, colony‐forming ability in soft agar and tumorigenicity of the DT cells were controlled by chromosome 1, but not by chromosome 11 or 12, indicating that normal human chromosome 1 carries a putative tumor‐suppressor gene(s) that affects various transformed phenotypes of DT cells.
Prevalence of Human Papillomavirus Types 16 and 18 in Cervical Carcinomas: A Study by Dot and Southern Blot Hybridization and the Polymerase Chain Reaction
Authors: Low Seng‐Hui , Thong Tuck‐Weng , Ho Tew‐Hong , Lee Yoke‐Sun , Morita Takashi , Singh Mulkit , Yap Eu‐Hian , Chan Yow‐Cheong
Published: August 2005

Histologically classified biopsies from 83 women with invasive cervical carcinoma were analyzed by dot blot hybridization for human papillomavirus (HPV) types 16 and 18 infection. Sixty of the 83 (72.3%) were found to contain HPV DNA, of which 43 (51.8%) contained HPV 16 DNA, 12 (14.5%) contained HPV 18 DNA and 5 (6.0%) contained both HPV 16 and 18 DNAs. Southern blot analysis on 65 specimens gave similar results. Of 23 specimens negative by dot blot, 21 were tested by the polymerase chain reaction. Seventeen of the 21 were positive for HPV DNA, of which 13 contained HPV 16 DNA and 4 contained both HPV 16 and 18 DNAs. In all, 95.1% (77/81) were positive for HPV 16 and/or 18 DNA sequences.
Detection of mRNAs of Carcinoembryonic Antigen and Nonspecific Cross‐reacting Antigen Genes in Colorectal Adenomas and Carcinomas by in situ Hybridization
Authors: Higashide Toshiyuki , Hinoda Yuji , Itoh Jun , Takahashi Hiroki , Satoh Yukihiko , Ibayashi Yumiko , Imai Kohzoh , Yachi Akira
Published: August 2005

Expression of mRNAs of carcinoembryonic antigen (CEA) and nonspecific cross‐reacting antigen (NCA) genes in colorectal carcinomas and adenomas was investigated by in situ hybridization (ISH) with specific biotinylated probes. Hybridization was clearly detected throughout the cytoplasm of 7 out of 15 adenomas and 13 out of 15 carcinomas with the CEA cDNA probe, and in 6 out of 15 adenomas and 10 out of 15 carcinomas with the NCA cDNA probe. The intensity of signal appeared to be stronger in carcinomas than that in adenomas, and the CEA and NCA mRNAs were expressed together in most of the positive tissue specimens. On the other hand, noninvaded tissues adjacent to the carcinoma did not show any signal except for 4 cases faintly stained with the NCA probe. This finding was partly confirmed by Northern blot analysis which indicated that the specific bands for the CEA and NCA mRNAs were more intense in RNAs from carcinoma tissues than in those from adjacent noninvaded tissues. These data suggest that the ISH technique with biotinylated probes could be of use for analyzing expression and localization of CEA and related genes on tissue sections.
Reversal of Methotrexate Cytotoxicity to Human Bone Marrow Cells and Leukemic K562 Cells by Leucovorin: Methotrexate Polyglutamates Formation as a Possible Important Factor
Authors: Koizumi Shoichi , Ueno Yoshiki , Ohno Ichiro , Ichihara Tsuyoshi , Tamaru Yoichi , Matsukawa Harumi
Published: August 2005

Methotrexate (MIX) is metabolized intracellularly to MTX‐polyglutamates (MTX‐PGs), which markedly inhibit several folate‐dependent enzymes. Polyglutamation defect, therefore, is one of the important factors in drug resistance. In this study, reversal of MTX cytotoxicity by l‐leucovorin (l‐LV) was investigated using normal human bone marrow granulocyte progenitor cells (G‐CFCs), and MTX‐sensitive and ‐resistant leukemic K562 cell lines; the latter showed diminished polyglutamation. Cytotoxicity of 10‐7M MTX to G‐CFCs was completely reversed by an equimolar concentration of l‐LV, but with higher MTX concentrations, relatively more l‐LV was required. The reversal of MTX cytotoxicity by l‐LV was more effective against bone marrow cells than MTX‐sensitive K562 cells; this reversal seemed to be correlated to the total intracellular MTX levels as well as MTX‐PG formation (low in bone marrow cells and high in K562 cells). When MTX‐sensitive and ‐resistant K562 cells were incubated with MTX under conditions in which the total intracellular MTX levels of both cells were similar, successful reversal of MTX toxicity by l‐LV was demonstrated in MTX‐resistant cells, but not in MTX‐sensitive cells, suggesting that an increase of MTX‐PG formation in MTX‐sensitive cells may explain the failure of l‐LV to overcome MTX cytotoxicity. In addition to competitive reversal of MTX cytotoxicity by LV, noncompetitive reversal relating to variable formation of MTX‐PGs is suggested to be another important factor in the mechanism of the reversal of MTX cytotoxicity by LV.
Etoposide Protects Mice from Radiation‐induced Bone Marrow Death
Authors: Yamada Sigeru , Ando Koichi , Koike Sachiko , Isono Kaichi
Published: August 2005

Etoposide is known to inhibit the activity of topoisomerase II, and to possess radiosensitizing effects. In this paper we show that pretreatment of mice with etoposide one day before whole‐body irradiation had a protective effect against radiation‐induced bone marrow death. The LD50/30 of mice given radiation alone was 8.26 Gy while that of mice given etoposide one day before whole‐body irradiation was 10.35 Gy. The number of endogenous colony‐forming units surviving in whole body‐irradiated mice was significantly increased by pretreatment with etoposide.
Effects of a Choline‐deficient Diet and a Hypolipidemic Agent on Single Glutathione S‐Transferase Placental Form‐positive Hepatocytes in Rat Liver
Authors: Yokota Kinichi , Singh Ushasi , Shinozuka Hisashi
Published: August 2005

Using the placental form of glutathione S‐transferase (GST‐P) as a marker of carcinogen‐initiated hepatocytes, we investigated how a choline‐deficient (CD) diet and BR931, a carcinogenic hypolipidemic agent, modify populations of single GST‐P‐positive hepatocytes. The liver of male Fischer rats (6‐7 weeks old) fed a CS or basal diet contained mostly single or double GST‐P‐positive hepatocytes. Feeding a CD diet for 2–4 weeks led to increases in the number of aggregates of two and three GST‐P‐positive hepatocytes. By 8–12 weeks, there was an emergence of discrete foci of GST‐P‐positive hepatocytes consisting of more than 20 hepatocytes. Feeding a BR931 diet for 4–8 weeks resulted in no significant change in the number of single GST‐P‐positive hepatocytes in the liver as compared to feeding a basal diet. It is suggested that single GST‐P‐positive hepatocytes in the liver of relatively young rats maintained on a commercial diet may represent endogenously initiated cells. A CD diet promotes endogenously initiated cells to form larger aggregates or foci of GST‐P‐positive cells.
Frequent Glycine‐to‐Aspartic Acid Mutations at Codon 12 of c‐Ki‐ras Gene in Human Pancreatic Cancer in Japanese
Authors: Nagata Yasuhiko , Abe Masumi , Motoshima Koichi , Nakayama Eiichi , Shiku Hiroshi
Published: August 2005

Point mutations at codons 12 and 13 of c‐Ki‐ras gene were analyzed in human pancreatic cancer. DNAs obtained from sample tissues were amplified by means of polymerase chain reaction and were analyzed by dot blot hybridization assays with oligonucleotide probes appropriate for detecting mutations at these codons. Out of 38 evaluated cases, point mutations at codon 12 were found in 35 cases; these mutations resulted in changes of the coded amino acid to aspartic acid in 24 cases, to valine in 9 cases, to arginine in 2 cases and to cysteine in one case. In one case, a glycine‐to‐aspartic acid mutation was found at codon 13. In two cases, two distinct mutations were simultaneously present. The frequency pattern of mutations at codon 12 was somewhat different from those given in two previous reports on the similar analysis of pancreatic cancers in European countries. This may indicate the presence of possible genetic or non‐genetic factors in determining preferential mutational patterns at these particular codons.
Analysis of Clonal Evolution in a Tumor Consisting of pSV2neo‐transfected Mouse Fibrosarcoma Clones
Authors: Enoki Yoshitaka , Niwa Ohtsura , Yokoro Kenjiro , Toge Tetsuya
Published: August 2005

The process of clonal evolution was analyzed in a line of methylcholanthrene‐induced mouse fibrosarcomas. The tumor cells were transfected with pSV2neo gene and 22 clones were randomly isolated. Genetically tagged clones were mixed and inoculated into syngeneic mice. Southern blot analysis revealed that one of the clones, no. 11, dominated both in tumors in situ and in lung metastatic nodules. No. 11 clone and other clones were similar in growth rates in vitro and in vivo, in spontaneous and experimental metastatic abilities, in immunogenicity, and in the capacity of intercellular communication in vitro. Although no. 11 clone overgrew other clones in vivo, this was not the case when clones were mixed and maintained in vitro. We conclude that clonal interactions in vivo may be responsible for the dominance of no. 11 clone in the tumor. It is likely that the preferential metastasis of no. 11 clone to the lung may be a simple reflection of the proliferative advantage of the dominant clone in the tumor in situ.
Particulate‐associated Protein Phosphatases of Rat Hepatomas as Compared with the Enzymes of Rat Liver
Authors: Shineha Ryuzaburo , Kikuchi Kunimi , Tamura Shinri , Hiraga Akira , Suzuki Yoichi , Tsuiki Shigeru
Published: August 2005

In the course of investigating the neoplastic alterations of protein phosphatases, the particulate fractions of rat liver and AH‐13, a strain of rat ascites hepatoma, were chromatographed on DEAE‐cellulose and assayed for protein phosphatase using glycogen synthase D and phosphorylase a as substrates. The synthase phosphatase activity of rapidly growing AH‐13 was due almost entirely to a divalent cation‐inhibited protein phosphatase, tentatively designated phosphatase N, the level of which was elevated remarkably in the hepatoma as compared with liver. Other hepatomas including primary hepatoma induced with 3′‐methyl‐4‐dimethylaminoazobenzene also exhibited high levels of this phosphatase. Phosphatase N exhibited Mr=49,000 (gel filtration) and has been partially purified with little alteration in properties. Partially purified phosphatase N was inhibited by divalent cations, rabbit skeletal muscle polypeptide inhibitor‐2 and heparin, and released the catalytic subunit of type‐1 protein phosphatase upon tryptic digestion. It is therefore apparent that phosphatase N is a type‐1 protein phosphatase. There is some evidence to suggest that the high levels of phosphatase N in neoplastic cells are due primarily to enhanced synthesis of its non‐catalytic (regulatory) subunit.
Active Oxygen‐mediated Cytotoxic and Antitumor Actions of Streptococcal Cytotoxic Protein
Authors: Higuchi Yoshihiro , Shoin Susumu , Matsukawa Shigeru
Published: August 2005

Streptococcal cytotoxic protein (SCP), obtained from the cell‐free extract of Streptococcus pyogenes, inhibited the uptake of [methyl‐3H]thymidine by Ehrlich ascites carcinoma cells depending on the concentration of fetal calf serum (FCS) added to the culture medium. The same results were found using sera from different animals. The inhibitory activity of SCP was completely suppressed by catalase but not by hydroxyl radical scavengers or superoxide dismutase. The antitumor activity of SCP in tumor‐bearing mice was inhibited by administration of catalase together with SCP. SCP enzymatically produced hydrogen peroxide in the presence of FCS as detected by the 2,2′‐azino‐di‐[3‐ethyl‐benzothiazoline‐(6)‐sulfonic acid]/horseradish peroxidase method. The kinetic parameters, Km and Vmax, for hydrogen peroxide production of SCP were 2.13% FCS and 0.53 nmol/min/μg SCP, respectively. These results indicate that SCP is an enzyme which produces hydrogen peroxide and exerts potent cytotoxic and antitumor effects using an active oxygen species, hydrogen peroxide, produced by the enzymatic reaction of SCP with an unknown substrate contained in FCS or sera from various animals and molecular oxygen.
A Novel Monoclonal Antibody against Squamous Cell Carcinoma
Authors: Inoue Masaki , Nakanishi Kazuyoshi , Sasagawa Toshiyuki , Tanizawa Osamu , Inoue Hirokazu , Hakura Akira
Published: August 2005

The monoclonal antibody, INS‐2, was raised against rat fibroblasts transformed by open reading frames E6 and E7 of human papillomavirus (HPV) DNA. In immunoperoxidase testing of frozen sections, the INS‐2 antibody was reactive with all squamous cell carcinomas of the uterine cervix and esophagus tested. In contrast, no antibody binding was detected with adenocarcinomas of various origins. Similarly, normal tissues, lymphoid cells and erythrocytes from multiple donors were negative, except that binding localized at basal cells in normal squamous epithelium was observed. Interestingly, strong staining was observed in dysplastic cells of cervical intraepithelial neoplasia and at the growing edge of squamous cell carcinomas. The antigen for the INS‐2 antibody is a non‐sialyl glycoprotein with Mw. 40,000 and appears to be a squamous cell‐specific cell differentiation marker, although it is not related to HPV‐DNA‐derived protein.
Evaluation of Mizoribine as an Immunosuppressant in Subrenal Capsule Assay Using Immunocompetent Mice
Authors: Chen Dong‐Yi , Kikuchi Hiroaki , Asamura Mitsuo , Gamoh Makio , Wakui Akira
Published: August 2005

We studied the application of mizoribine (MZR) to normal immunocompetent mice in subrenal capsule assay (SRCA) by means of tumor growth curve determination, histological analysis and autoradiography. At 400 mg/kg, MZR prolonged the actual tumor growth and moderately reduced the host reaction. Doses below 200 mg/kg did not effectively suppress the host reaction. The maximal weight loss of mice in the 400 mg/kg group reached 29%, but did not exceed 10% within 8 days. Hence, we applied 400 mg/kg of MZR to SRCA for up to eight days for cancer chemotherapy testing. This dose of MZR did not affect the labeling index of tumor cells compared with the control.
Significant Increase of 8‐Hydroxydeoxyguanosine in Liver DNA of Rats Following Short‐term Exposure to the Peroxisome Proliferators Di(2‐ethylhexyl)phthalate and Di(2‐ethylhexyl)adipate
Authors: Takagi Atsuya , Sai Kimie , Umemura Takashi , Hasegawa Ryuichi , Kurokawa Yuji
Published: August 2005

8‐Hydroxydeoxyguanosine (8‐OH‐dG) levels were examined in liver and kidney DNA after di(2‐ethylhexyl)phthalate (DEHP), di(2‐ethylhexyl)adipate (DEHA) and phthalic anhydride administration to male 6‐week‐old F‐344 rats in the diet at concentrations of 1.2, 2.5 and 1.5%, respectively. Significant increases in 8‐OH‐dG levels were observed only in the liver (target organ of DEHP and DEHA carcinogenesis) DNA after 1 and 2 weeks of treatment with DEHP and DEHA, respectively. The results suggest the involvement of oxidative DNA damage in hepatocarcinogenesis by peroxisome proliferators.
Antimetastatic and Growth‐inhibitory Effects of N‐Acetylchitohexaose in Mice Bearing Lewis Lung Carcinoma
Authors: Tsukada Keiko , Matsumoto Tatsuji , Aizawa Kazuhiro , Tokoro Akio , Naruse Ryu‐suke , Suzuki Shigeo , Suzuki Masuko
Published: August 2005

N‐Acetylchitohexaose, a water‐soluble oligosaccharide was found to display a significant anti‐metastatic effect against Lewis lung carcinoma (LLC) transplanted into C57BL/6 mice, giving rise to a 40–50% inhibition ratio of pulmonary metastasis when administered intravenously (1 mg/kg) on day 6 after the tumor implantation (5 × 105 cells/mouse). It was also revealed that this hexaose had a significant growth‐inhibitory effect against the local tumor of the same carcinoma (a 20–30% inhibition ratio), showing an enhancing effect on concomitant immunity in local tumor‐resected mice. This oligosaccharide was also shown to enhance the tumoricidal effect of splenic T lymphocytes against LLC and P‐815 mastocytoma cells and to increase the natural killer activity of splenic T lymphocytes, assayed with YAC‐1 cells as the target.
Influence of Cocktails of Labeled Monoclonal Antibodies on the Localization of Antibodies in Human Tumor Xenografts
Authors: Watanabe Yuji , Endo Keigo , Saga Tsuneo , Koizumi Mitsuru , Sakahara Harumi , Nakai Toshiharu , Hosono Makoto , Yao Zheng‐Sheng , Kuroki Masahide , Matsuoka Yuji , Konishi Junji
Published: August 2005

In order to evaluate the usefulness of cocktails of labeled monoclonal antibodies (MoAbs) recognizing different antigen molecules to localize human cancer xenografts, we have compared the potential of three MoAbs recognizing representative cancer‐associated CA 19–9, 17–1A and CEA antigens when administered alone or in combination. Specific binding of radioiodinated F(ab′)2 fragments of these three MoAbs was observed to human colorectal cancer cell lines SW1116, LS180 and Co‐3. The percentage of in vitro cell binding of a cocktail of any two MoAbs to cancer cells was equal to the average of those obtained with the two MoAbs alone. The three MoAbs were preferentially localized in tumor tissues xenografted in nude mice. When cocktails of any two MoAbs were used, the obtained tumor‐to‐normal tissue ratios and percent of injected dose per gram of tumor were between the levels obtained for each MoAb when administered alone, in all three tumors transplanted in nude mice. These data suggest that, although cocktails of labeled MoAbs recognizing different antigens may extend the spectrum of tumor specificities, their use does not improve the tumor localization ability of MoAb‐conjugates.
The Effect of High‐energy Underwater Shock Waves on Implanted Urinary Bladder Cancer in Rabbits
Authors: Hoshi Senji , Orikasa Seiichi , Kuwahara Masa‐aki , Yoshikawa Kazuyuki , Ohyama Chikara , Satoh Makoto , Kawamura Sadafumi , Nose Masato
Published: August 2005

We have examined the effects of high‐energy shock waves (HESW) on implanted urinary bladder cancer in rabbits. The bladder cancer was exposed to 2000 to 6000 shots of focused HESW under ultrasound guidance. Although only focal necrosis of the tumor was seen in the one‐day HESW exposure (2000 shots), wider and deeper necrosis was observed in the tumors following serial HESW (4000 or 6000 shots; 2 or 3 days). These results indicate that serial HESW exposure has destructive effects on implanted bladder cancer in rabbits.
Alterations of Mouse Proto‐oncogenes in Sarcomas Induced after Transplantation of Human Tumors in Athymic Nude Mice
Authors: Yuasa Yasuhito , Yamazaki Hitoshi , Maruo Kohji , Ueyama Yoshito , Shibuya Masabumi , Tamaoki Norikazu
Published: August 2005

During serial subcutaneous transplantation of several types of human tumors into nude mice, the local development of malignant mouse‐specific sarcomas has been observed. Although the frequency of sarcoma induction is low, this phenomenon is very important because the mouse‐specific sarcomas completely replaced the human tumors during serial transplantation. The DNA of five independently induced mouse‐specific sarcomas was transfected into NIH/3T3 cells in order to detect oncogenes associated with mouse‐specific sarcoma induction. Two of these DNAs were found to carry activated mouse c‐N‐ras and c‐Ki‐ras genes. The sequence analysis of the molecularly cloned mouse c‐N‐ras oncogene showed a single nucleotide transition from G to A at the 12th codon. This results in substitution of aspartic acid for glycine at this position. The mouse c‐myc gene was also found to be amplified in a sarcoma. In these mouse sarcoma DNAs, human Alu sequences were not detected. These data strongly suggest that the mouse‐specific sarcomas were not induced by the transfer of human transforming sequences but by the alterations of mouse proto‐oncogenes.
Production of Basic Fibroblast Growth Factor‐like Factor by Cultured Human Cholangiocellular Carcinoma Cells
Authors: Matsuzaki Kouichi , Yoshitake Yoshino , Miyagiwa Miki , Minemura Masami , Tanaka Michio , Sasaki Hiroshi , Nishikawa Katsuzo
Published: August 2005

An extract of cultured human cholangiocellular carcinoma cells (HuCC‐T1) was found to contain high mitogenic activity for BALB/c3T3 cells. The growth factor eliciting most of the mitogenic activity was purified and concluded to be identical with basic fibroblast growth factor (bFGF)‐like factor on the basis of its molecular weight and heparin‐Sepharose elution profile, and the results of immunoblotting and radioimmunoassay. HuCC‐T1 cells also secreted bFGF‐like factor into serum‐free medium. A combination of insulin and transferrin or bovine serum albumin stimulated the growth of HuCC‐T1 cells in serum‐free medium. However, bFGF did not stimulate their growth in the presence and absence of these supplements. Neutralizing monoclonal antibody against bFGF did not inhibit growth. These results indicate that bFGF‐like factor is not a growth factor for this cell line.
Red and Blue Distinctive Mucin‐histochemical Types of Japanese Colorectal Mucosa
Authors: Yanagisawa Akio , Yotsumoto Koichi , Kitagawa Tomoyuki , Sugano Haruo , Kato Yo
Published: August 2005

Mucin‐histochemical characteristics of normal human colorectal mucosa were investigated utilizing Culling et al.'s staining method which distinguishes the mode of C8‐O‐acylation of sialomucins. Normal mucosae of cecum, ascending, transverse and descending colon and rectum were obtained from autopsy and biopsy material. Japanese colorectal mucosa stained either entirely red or entirely blue, in contrast to previous reports dealing with Caucasians where all the normal mucosa reportedly stained red. The ratio of red to blue colon cases varied to some extent with age, i.e. it was found to be 1:1 in children aged 0 to 4, 2:1 in the 5–20 age group, and 4:1 in people older than 21 years, suggesting a tendency of shift from blue to red during early life in Japan. Each individual Japanese adult colorectal mucosa may thus be classified into either red or blue type mucin‐histochemically.
Griffonia simplicifolia Agglutinin‐2‐binding Glycoprotein as a Novel Carbohydrate Antigen of Human Colonic Carcinoma
Authors: Nakayama Jun , Okano Akira , Maeda Hiroshi , Miyachi Mami , Ota Hiroyoshi , Katsuyama Tsutomu , Kanai Masamitsu
Published: August 2005

Griffonia simplicifolia agglutinin‐2‐binding glycoprotein (GBG) in human colonic carcinoma was examined immunochemically and histochemically. GBG was extracted from colonic carcinoma as a serum‐type glycoprotein of 160 kilodaltons. GBG was not identical with carcinoembryonic antigen (CEA), since its molecular weight and localization in tissue sections were different from those of CEA. The non‐reducing terminals of GBG probably carry N‐acetylglucosamine, but not blood group determinants. Furthermore, GBG was released by phosphatidylinositol‐specific phospholipase C from cell membrane. GBG was suggested to be anchored to the membrane via linkage to a glycosyl‐phos‐phatidylinositol molecule. Among colonic carcinoma‐associated antigens, serum‐type glycoproteins having N‐acetylglucosamine at non‐reducing terminals have not previously been reported. GBG is a novel carbohydrate antigen of human colonic carcinoma.
Tumor Growth Rate and Prognosis of Breast Cancer Mainly Detected by Mass Screening
Authors: Kuroishi Tetsuo , Tominaga Suketami , Morimoto Tadaoki , Tashiro Hideya , Itoh Sueyoshi , Watanabe Hiromu , Fukuda Mamoru , Ota Jun , Horino Toshio , Ishida Tsunehiro , Yokoe Takao , Enomoto Kohji , Kashiki Yoshitomo , Ogita Masami
Published: August 2005

To investigate the relationship between the tumor growth rate of the primary breast cancer and its prognosis, records for 122 breast cancer patients in 9 hospitals in Japan were retrospectively reviewed. These records contained at least two measurements of the same tumor mass in the breast. So the growth rate was estimated from these measurements taken at different points in time. The doubling time of the breast tumors showed an approximately log‐normal distribution. The geometric mean of doubling times for all cases was 174 days. The solid‐tubular histologic type of carcinoma had the shortest geometric mean of doubling time (126 days), the scirrhous carcinoma had the second shortest one (205 days), and the papillotubular carcinoma had the longest one (252 days). The patients with shorter doubling time of tumor tended to have a poorer prognosis. The Cox multiple regression analysis showed that the tumor growth rate was related significantly with survival, after adjusting for other covariates such as clinical stage, lymph node metastasis, age of patient, histological type, and year of treatment.
Combination Effects of Interferon‐γ and Cholera Toxin on Induction of Differentiation of an Insensitive U‐937 Clone
Authors: Iwanami Masahide , Takeda Ken , Iwamoto Sanju , Konno Kunio
Published: August 2005

We examined the combination effect of interferon‐γ (IFN‐γ) and cholera toxin and the role of cAMP in the induction of differentiation of a differentiation‐insensitive U‐937 clone, in which the reactivity to differentiation‐inducers was decreased. IFN‐γ (100 units/ml) or cholera toxin (10–9M) alone only marginally induced various differentiation‐associated characteristics such as NBT‐reducing activity, phagocytic activity, α‐naphthyl acetate esterase activity and surface markers. However, when combined with each other, they significantly induced these markers. Other cAMP‐inducing agents such as prostaglandin E2, forskolin, epinephrine and isoproterenol did not induce NBT‐reducing activity, either alone or in combination with IFN‐γ. However, all these cAMP‐inducing agents significantly increased intracellular cAMP levels. Tumor necrosis factor, interleukin 6 or granulocyte/macrophage colony‐stimulating factor alone did not induce NBT‐reducing activity, but they could induce activity when combined with cholera toxin. These results suggest that enhancement of induction of differentiation by cholera toxin in combination with IFN‐γ or other cytokines may not be merely due to increased cAMP levels. There seems to be a transduction signal other than cAMP coupling with cholera toxin to stimulate induction of differentiation of an insensitive U‐937 clone.
In vitro Sensitivity Test of Breast Cancer Cells to Hormonal Agents in a Radionucleotide‐incorporation Assay
Authors: Watanabe Toru , Junzheng Wu , Morikawa Kiyoshi , Fuchigami Masahiro , Kuranami Masaru , Adachi Isamu , Yamaguchi Ken , Abe Kaoru
Published: August 2005

Breast cancer cell lines (MCF‐7, T47D, BT‐20 and STT‐11) and fresh cells from malignant effusions of eight breast cancer patients were examined for their in vitro sensitivity to 17β‐estradiol (E2), tamoxifen and toremifene in a miniaturized, improved nucleic acid precursor incorporation assay (MINI assay). Seven of the eight patients received either tamoxifen or toremifene following a MINI assay and the correlation was examined between in vitro sensitivity and clinical responses to the hormonal agents. In cell lines, E2 stimulated thymidine incorporation by estrogen receptor (ER)‐rich cells, MCF‐7 and T47D, but not by ER‐poor cells, BT‐20 and STT‐11. Tamoxifen induced both ER‐mediated and ‐unmediated effects in ER‐rich cells. The latter effect was also observed in ER‐poor cells. Toremifene had less ER‐unmediated effect in all of the cells tested than tamoxifen did. The ER‐mediated effect of toremifene was weaker than that of tamoxifen in cell lines but was equipotent to tamoxifen in fresh cells. E2 affected thymidine incorporation by cells withdrawn from patients who showed a partial response to the anti‐estrogens. No clear correlation was demonstrated between in vitro sensitivity to anti‐estrogens of fresh cells and clinical response to these agents. The present results suggest that 1) the MINI assay is a useful system to investigate hormonal effects on breast cancer cell lines; 2) clinical responses to anti‐estrogens are not predicted by in vitro response to the agents but might be predicted by the in vitro response to E2; and 3) toremifene has a smaller non‐specific effect on breast cancer cells than tamoxifen and is equipotent to tamoxifen in the ER‐mediated effect in vitro.
Induction of Gastrointestinal Tumors in Mice Fed the Fungicide Folpet: Possible Mechanisms
Authors: Nyska Abraham , Waner Trevor , Paster Zvi , Bracha Peretz , Gordon Elliot B. , Klein Baruch
Published: August 2005

Dietary administration of the fungicide folpet, N‐(trichloromethylthio)phthalimide, to B6C3F1 mice at dose levels of 1,000, 5,000 and 10,000 ppm induced a dose‐related appearance of duodenal atypical hyperplasia, adenomas and adenocarcinomas. The appearance in some of these animals of gastric papillomas and gastric squamous cell carcinomas was correlated in many instances to the presence of duodenal obstructions. It is suggested that the gastric lesions appeared subsequent to, and as an indirect result of, these partial lumenal duodenal obstructions. We suggest that the presence of duodenal obstructions is consistent with the notion that reflux of folpet, bile acids and pancreatic enzymes into the stomach may have acted to irritate and consequently stimulate local neoplastic proliferation. In addition, the duodenal obstructions may have resulted in delayed emptying time of the stomach contents with consequential stagnation. This would cause high concentrations of folpet to act locally on the gastric mucosa.
Removal of Immunosuppressive Substance in Cancer Patients’ Serum
Authors: Ishiko Osamu , Deguchi Masaaki , Tatsuta Ichiro , Naka Keizo , Hirai Kozo , Nakata Shinichi , Honda Kenichi , Sugawa Tadashi
Published: August 2005

Anemia‐inducing substance (AIS) appears in plasma as cancer progresses. In this study, a non‐coated charcoal column was used to remove AIS from the cachectic plasma obtained from patients with advanced cancer. AIS could be completely removed by 6 cycles of adsorption using this column. Similar data were obtained in an experiment using VX‐2‐transplanted rabbits. These observations raised the possibility that plasmapheresis with a non‐coated charcoal column may be available as a new means of immunotherapy for advanced cancer.
Second Malignant Lymphomas and Leukemias in the National Cancer Center from 1962 to 1987
Authors: Kobayashi Yumiko , Arimoto Hiroko , Watanabe Shaw
Published: August 2005

Occurrence of second hematopoietic malignancies (SHM) among 49,163 patients with cancer, who had been admitted to the National Cancer Center Hospital from 1962 to 1987, was investigated. Forty‐two cases of malignant lymphomas (38 non‐Hodgkin lymphomas, 3 Hodgkin's diseases and 1 multiple myeloma) and 17 cases of leukemias (11 acute leukemias, 4 chronic leukemias and 2 myelodysplastic syndromes) developed as SHM. Second malignant lymphomas were 1.37 times more frequent than expected (P<0.05), whereas no excess incidence was seen in second leukemias. The incidence of malignant lymphomas was 2.2 times higher than expected in patients with initial stomach cancer (P<0.01). Two‐thirds of second non‐Hodgkin lymphomas occurred in extranodal regions. Nodal lymphomas were more prevalent in cases treated with chemotherapy and/or radiotherapy. Second leukemias were all of myeloid origin except one case of acute lymphoblastic leukemia. Etiological heterogeneity of SHM is discussed in relation to treatment and other risk factors.
Okadaic Acid and Phorbol Esters: Comparative Effects of These Tumor Promoters on Cell Transformation, Intercellular Communication and Differentiation in vitro
Authors: Katoh Fumitaka , Fitzgerald D. James , Giroldi Laurence , Fujiki Hirota , Sugimura Takashi , Yamasaki Hiroshi
Published: August 2005

Okadaic acid is a non‐12‐O‐tetradecanoylphorbol‐13‐acetate (TPA)‐type tumor promoter in the mouse skin carcinogenesis system. Here we report on the in vitro activity of okadaic acid in 3 assay systems: BALB/c 3T3 cell transformation, gap junctional intercellular communication (GJIC) in various cell types, and inhibition of induction of differentiation of Friend virus‐transformed murine erythroleukemia (MEL) cells. The activity of okadaic acid was compared to that of the phorbol ester tumor promoters TPA and phorbol‐12,13‐didecanoate (PDD). In a test system involving a 2‐week exposure of BALB/c 3T3 cells following 3‐methylcholanthrene initiation, okadaic acid at a concentration of 10 ng/ml was equipotent to PDD as a promoter of cell transformation (4.9 and 3.7 foci/dish, respectively). Longer exposures to okadaic acid resulted in cytotoxicity. Okadaic acid‐generated as well as PDD‐generated transformed foci displayed a selective lack of GJIC between focus cells and surrounding normal cells, i.e., transformed cells communicate among themselves but not with surrounding cells. However, in contrast to TPA, there was no inhibition by okadaic acid, except at toxic doses, of homologous GJIC in BALB/c 3T3 cells or human and mouse keratinocytes. Furthermore, okadaic acid, unlike TPA, did not inhibit MEL cell differentiation. Together, these results indicate that okadaic acid acts as a promoter of cell transformation but that its mechanism of action is different from that of the phorbol ester tumor promoters.
c‐erbB‐2 and c‐erbA‐1 (ear‐1) Gene Amplification and c‐erbB‐2 Protein Expression in Japanese Breast Cancers: Their Relationship to the Histology and Other Disease Parameters
Authors: Uehara Toshitaka , Kaneko Yasuhiko , Kanda Naotoshi , Yamamoto Tadashi , Higashi Yasuhiro , Nomoto Chikao , Izumo Toshiyuki , Takayama Syojiro , Sakurai Masaharu
Published: August 2005

We studied c‐erbB‐2 and c‐erbA‐1 (ear‐1) gene amplification, and c‐erbB‐2 protein expression in 123 primary Japanese breast cancers. c‐erbB‐2 amplification was found in 19 of the 123 tumors (15%), and c‐erbA‐1 was coamplified in 7 of the 19. The presence or absence of c‐erbB‐2 amplification correlated with the grade of cellular atypism (P= 0.008), or that of mitotic index (P= 0.002), but not with the histologic types. The tumor size (P= 0.04) and the lymph node status (P= 0.06) were associated, but the patients’ age, the TNM stage, or the presence or absence of estrogen or progesterone receptors was not associated, with c‐erbB‐2 amplification. There were no differences in the histologic type, cellular atypism, mitotic index, and other disease parameters between tumors with c‐erbB‐2 amplification only and those with coamplification of c‐erbB‐2 and c‐erbA‐1. Paraffin sections from all 19 tumors with c‐erbB‐2 amplification, and those from only one of 104 tumors without the amplification were positively stained with polyclonal anti‐c‐erbB‐2 protein antibody. Since the correlation between the amplification and the protein expression was excellent, such immunohistochemical studies may be substituted for the time‐consuming DNA studies using Southern blotting.
Granulocyte Colony‐stimulating Factor‐dependent Growth of an Acute Myeloblastic Leukemia Cell Line
Authors: Nara Nobuo , Suzuki Toshiya , Nagata Kaoru , Tohda Shuji , Yamashita Yoko , Nakamura Yuichi , Imai Yasufumi , Morio Tomohiro , Minamihisamatsu Masako
Published: August 2005

We report herein the establishment and characterization of a granulocyte colony‐stimulating factor (G‐CSF)‐dependent acute myeloblastic leukemia (AML) cell line. The cell line, designated as OCI/AML 1a, has been cultured in the presence of G‐CSF and has shown exponential growth for over two years. The cells growing in suspension culture resembled myeloblasts on the basis of morphologic, cytochemical and surface phenotypic analyses. Other CSFs, interleukin‐3 and granulocyte‐macrophage colony‐stimulating factor did not support the growth of OCI/AML 1a cells so well as G‐CSF. The effect on the growth of OCI/AML 1a cells of G‐CSF was almost completely abolished by neutralizing monoclonal anti‐G‐CSF antibody. These findings showed that OCI/AML 1a cells required G‐CSF for growth. OCI/AML 1a cell line will be valuable for studies of the biological nature, proliferation and differentiation of leukemic cells. Furthermore, OCI/AML 1a cells should be useful for determining the mechanism by which G‐CSF induces the growth of hemopoietic cells.
Effect of Interferon‐α in Patients with Chronic Myelogenous Leukemia in the Accelerated Phase: Cytogenetic and Molecular Studies
Authors: Ogura Hiromi , Tani Kenzaburo , Kozai Yasuji , Watari Kiyoshi , Kodo Hideki , Ozawa Keiya , Asano Shigetaka , Takaku Fumimaro
Published: August 2005

Human interferon‐α (IFN‐α) has been shown to be effective in the treatment of Philadelphia chromosome (Ph1)‐positive chronic myelogenous leukemia (CML) in the benign stable phase. The present study indicates that IFN‐α may have a suppressive effect on Ph1‐positive clones not only in the early stable phase but also in the accelerated phase with additional chromosomal abnormalities in some patients. In this study, in addition to 5 benign‐phase patients, 3 patients with CML in the accelerated phase who had additional chromosomal abnormalities were treated with IFN‐α. The presence of the Ph1‐positive clone was estimated by chromosomal analysis and by Southern analysis at the DNA level using a 3′ breakpoint cluster region (bcr) probe. Hematological remission and the suppression of proliferation of Ph1‐positive clone to various extents were achieved by IFN‐α treatment in 2 benign‐phase patients and 3 patients with additional chromosomal abnormalities. Interestingly, in one of the latter three patients, Ph1‐positive clones with or without additional chromosomal abnormalities were completely suppressed judging from chromosomal analysis and from the disappearance of bcr gene rearrangements.