bluuebunny/crossref_metadata_2025 huggingface dataset:
Pathological Characteristics of Gastric Carcinomas in the Very Old
Authors: Inoshita Naoko , Yanagisawa Akio , Arai Tomio , Kitagawa Tomoyuki , Hirokawa Katsuiku , Kato Yo
Published: August 2005

A total of 69 gastric carcinomas of very old people (aged ≥85) were collected and pathologically analyzed in comparison with those of young to middle‐aged (30–39) and elderly (65–69) people, with special attention to their phase. In the very old, almost all (34/35) carcinomas in the early phase belonged to well‐differentiated categories. In the advanced phase, half of them (17/34) were classified into poorly differentiated categories when determined from the predominant pattern, but a well‐differentiated pattern almost always coexisted in the superficial site. Thus, the gastric carcinomas in the very old may principally develop as well‐differentiated carcinomas which then progress to poorly differentiated carcinomas with time, in contrast to those of the young to middle‐aged, most of which emerged from the very early phase as poorly differentiated lesions. The gross features of the carcinomas were also in line with these histological observations. The carcinomas of the elderly showed distinct similarity to those of the very old. The results suggest that poorly differentiated carcinomas of the young to middle‐aged and the old may be better classified and analyzed separately in view of the generally recognized etiological (e.g., specifically close causal relationship with environmental factors of the intestinal‐type carcinoma of the old) and biological (e.g., practically no tendency for hematogenous metastasis of the diffuse‐type carcinoma of the young to middle‐aged) differences, although in the General Rules for Gastric Cancer Study of Japan, both are placed in the same category, por (por2).
Expression of Telomerase Catalytic Component, Telomerase Reverse Transcriptase, in Human Gastric Carcinomas
Authors: Yasui Wataru , Tahara Hidetoshi , Tahara Eiji , Fujimoto Junya , Nakayama Jun‐ichi , Ishikawa Fuyuki , Ide Toshinori , Tahara Eiichi
Published: August 2005

Telomerase activity is believed to be crucial for cellular immortality, which is considered to participate in the development of a majority of human cancers. Human telomerase reverse transcriptase (TERT) has recently been identified as a catalytic subunit of telomerase. We examined the expression of TERT and other telomerase components such as human telomerase RNA component (hTR, encoded by TERC) and human telomerase‐associated protein (TEP1) by reverse transcription‐polymerase chain reaction in human gastric carcinomas and non‐neoplastic mucosa, in addition to measuring the telomerase activity. Of 20 gastric carcinomas examined, 18 (90%) and 18 (90%) showed increased expression of TERT and higher telomerase activity in comparison with corresponding non‐neoplastic mucosa, respectively. Increased expression of hTR/TERC was also observed in 15 (75%) of the gastric carcinomas. Immunohistochemically, strong expression of TERT protein was detected in the nuclei of the tumor cells of all carcinoma tissues, while the expression of TERT in non‐neoplastic mucosal cells as well as stromal elements (except lymphocytes) was weak or negative. These findings suggest that increased TERT expression associated with telomerase activity may serve as a novel marker for the diagnosis of stomach cancer.
Relationship between Protein Levels and Gene Expression of Dihydropyrimidine Dehydrogenase in Human Tumor Cells during Growth in Culture and in Nude Mice
Authors: Takechi Teiji , Okabe Hiroyuki , Fujioka Akio , Murakami Yuko , Fukushima Masakazu
Published: August 2005

Protein levels and gene expression of dihydropyrimidine dehydrogenase (DPD), the rate‐limiting enzyme for degradation of 5‐fluorouracil, were studied in two human tumor cell lines (fibrosarcoma HT‐1080 and pancreatic carcinoma MIAPaCa‐2) in various growth phases of the cultured cells and of tumor xenografts implanted into nude mice. DPD catalytic activity and DPD protein content in cytosolic preparations were determined by means of radioenzymatic assay and western blot analysis, respectively. Relative DPD mRNA expression was determined by using a semi‐quantitative reverse transcription‐polymerase chain reaction in which glyceraldehyde‐3‐phosphate dehydrogenase mRNA was used as an internal standard. DPD activity and protein content in cultures of both cell lines increased in proportion to cell density (DPD activities ranged from undetectable to 84 pmol/min/mg protein in the HT‐1080 cells and from undetectable to 335 pmol/min/mg protein in the MIAPaCa‐2 cells). DPD mRNA levels, on the other hand, tended to decrease slightly during cell growth. DPD activity and protein content in HT‐1080 tumor xenografts increased during growth in proportion to tumor weight (DPD activities ranged from 7 to 131 pmol/min/mg protein), but DPD mRNA levels did not correlate with tumor weight. DPD activity and protein content in MIAPaCa‐2 tumor xenografts did not change much, and seemed to have already plateaued, since the tumors were small (weighing about 30 mg). These findings suggest that DPD protein expression during tumor growth is controlled at the post‐transcriptional level.
CD44H Participates in the Intrahepatic Growth of Murine Colon 26 Adenocarcinoma Cells
Authors: Ogoshi Takahiko , Ishii Seiichi , Mizoi Takayuki , Harada Nobuhiko , Sato Wataru , Saito Kazuya , Ogawa Hitoshi , Inabe Keiko , Shiiba Ken‐ichi , Matsuno Seiki
Published: August 2005

The purpose of this study was to determine if CD44, a metastasis‐associated cell adhesion molecule, is involved in the hepatic colonization by murine colon 26 adenocarcinoma cells. Indirect membrane immunofluorescence and FACS analysis showed strong expressions of CD44 and integrin β1 on colon 26 cells. Injection of 1×105 colon 26 cells into the superior mesenteric vein of syngeneic BALB/c mice produced macroscopic hepatic nodules in 92% (22/24) of the mice 14 days after inoculation. When colon 26 cells were pretreated with an anti‐CD44 monoclonal antibody (mAb), IM7, only 30% (3/10) of the mice produced minute nodules in the liver on day 14 (P<0.001), though IM7 did not inhibit growth of the cells in vitro. Pretreatment of colon 26 cells with an anti‐integrin β1 mAb did not significantly block the hepatic metastasis. Histologically, microcolonies of tumor cells were detected in all of the livers on day 14 including the IM7‐pretreatment mice that were free of gross nodules. However, percentages of tumor‐occupied areas in the liver were consistently lower in IM7‐pretreatment mice than in control mice (0.82% vs. 5.0% on day 14; P<0.005). Reverse transcription‐polymerase chain reaction (RT‐PCR) amplification of mRNA revealed that colon 26 cells and splenocytes only expressed the hematopoietic isoform of CD44 (CD44H), which had no insertion of variant exons, while normal colonocytes expressed possible variant isoforms. These data suggest that malignant transformation of murine colonic epithelium altered the expression pattern of CD44 isoforms and that CD44H participates in the intrahepatic growth of colon 26 cells.
In situ mRNA Hybridization Technique for Analysis of Human Telomerase RNA in Gastric Precancerous and Cancerous Lesions
Authors: Hiyama Toru , Yokozaki Hiroshi , Kitadai Yasuhiko , Tahara Eiji , Tahara Hidetoshi , Ide Toshinori , Haruma Ken , Yasui Wataru , Kajiyama Goro , Tahara Eiichi
Published: August 2005

Telomerase, the ribonucleoprotein enzyme that elongates telomeres, is repressed in normal somatic cells but is reactivated during tumor progression. The purpose of this study was to investigate the localization of human telomerase RNA (hTR) expression in human gastric precancerous and cancerous lesions by using in situ mRNA hybridization (ISH) with avidin‐biotin staining. We also examined telomerase activity in these lesions by using hybridization protection assay connected with a telomeric repeat amplification protocol (TRAP/HPA). Analyzed tissue samples were as follows; 132 cases of chronic atrophic gastritis without intestinal metaplasia, 115 incomplete‐type intestinal metaplasias, 40 complete‐type intestinal metaplasias, 23 hyperplastic polyps, 23 tubular adenomas and 26 adenocarcinomas. In ISH analysis, high levels of hTR expression were observed preferentially in the nuclei at the single‐cell level. hTR‐expressing cells in carcinomas and adenomas were significantly more frequent than those of the other lesions (P<0.001). The expression pattern of hTR in carcinoma and adenoma tissues was heterogeneous and similar intratumor heterogeneity was detected in Ki‐67 immunoreactivity. Infiltrating lymphocytes in tissues also exhibited high levels of hTR expression. In TRAP/HPA analysis, carcinomas had significantly more frequent positivity for telomerase activity and a higher level of telomerase activity than the other lesions (P<0.05). However, the amount of telomerase activity did not parallel the expression level of hTR. Our data suggest that hTR expression increases in the early stages of stomach carcinogenesis and that sufficient synthesis of hTR is a prerequisite for telomerase reactivation in tumorigenesis.
Targeted Gene Transfer for Adenocarcinoma Using a Combination of Tumor‐specific Antibody and Tissue‐specific Promoter
Authors: Kurane Shuji , Krauss John C. , Watari Eiji , Kannagi Reiji , Chang Alfred E. , Kudoh Shoji
Published: August 2005

We have developed a highly specific gene transfer method for adenocarcinoma using a monoclonal antibody against tumor‐specific antigen coupled with a plasmid containing the carcinoembryonic antigen (CEA)‐specific promoter. The chimeric CEA promoter (CC promoter), which contained an enhancer from the immediate early gene of cytomegalovirus and the CEA promoter, achieved 4‐ to 5‐fold higher transgene expression in CEA‐producing cells than the original CEA promoter while maintaining CEA specificity. Furthermore, a complex of a monoclonal antibody against Lewis Y antigen (LYA), the CC promoter‐containing plasmid and cationic liposomes (DOTAP) achieved specific gene expression in CEA‐producing and LYA‐positive adenocarcinoma cell lines that was 200‐fold more efficient than in CEA‐non‐producing and LYA‐negative cell lines during a short in vitro incubation. This strategy may be applicable for clinical gene therapy.
A New Antitumor Agent Amrubicin Induces Cell Growth Inhibition by Stabilizing Topoisomerase II‐DNA Complex
Authors: Hanada Mitsuharu , Mizuno Satoko , Fukushima Akihisa , Saito Yoshikazu , Noguchi Toshihiro , Yamaoka Takashi
Published: August 2005

Amrubicin is a novel, completely synthetic 9‐aminoanthracycline derivative. Amrubicin and its C‐13 alcohol metabolite, amrubicinol, inhibited purified human DNA topoisomerase II (topo II). Compared with doxorubicin (DXR), amrubicin and amrubicinol induced extensive DNA‐protein complex formation and double‐strand DNA breaks in CCRF‐CEM cells and KU‐2 cells. In this study, we found that ICRF‐193, a topo II catalytic inhibitor, antagonized both DNA‐protein complex formation and double‐strand DNA breaks induced by amrubicin and amrubicinol. Coordinately, cell growth inhibition induced by amrubicin and amrubicinol, but not that induced by DXR, was antagonized by ICRF‐193. Taken together, these findings indicate that the cell growth‐inhibitory effects of amrubicin and amrubicinol are due to DNA‐protein complex formation followed by double‐strand DNA breaks, which are mediated by topo II.
A Long‐term Follow‐up Study on Risk Factors for Hepatocellular Carcinoma among Japanese Patients with Liver Cirrhosis
Authors: Tanaka Keitaro , Sakai Hironori , Hashizume Makoto , Hirohata Tomio
Published: August 2005

To identify virological parameters (serostatus of hepatitis B surface antigen [HBsAg] and antibodies to hepatitis C virus [anti‐HCV], HCV genotypes and HCV‐RNA titer) and other clinico‐biological and lifestyle variables that may influence or predict the development of hepatocellular carcinoma (HCC) in cirrhosis, we followed 100 cirrhotic patients without HCC, who visited Kyushu University Hospital between 1985 and 1987, until the end of 1995 (follow‐up rate: 98%; average follow‐up period: 5.3 years). After elimination of 4 patients who developed HCC or were censored within the initial 6 months, 37 (39%) out of 96 patients developed HCC during follow‐up. As compared with HBsAg(+) patients, anti‐HCV(+) HBsAg(–) patients demonstrated significantly elevated HCC risk (adjusted hazard ratio [HR]=5.85, 95% confidence interval [CI] 1.65–20.67). Genotype 1 HCV infection was not associated with increased risk compared with genotype 2 (HR = 0.64, 95% CI 0.21–1.99). For genotype 1 HCV infection, patients with HCV‐RNA levels <1 Meq/ml tended to present lower risk than patients with ≥1 Meq/ml (P= 0.03). Male sex, advanced Child's class, lower serum albumin, and higher serum aminotransferase and α‐fetoprotein were also found to be strong predictors. Overall, drinking and smoking habits were not associated with significantly elevated risk. Among virological parameters, anti‐HCV positivity and, possibly high HCV‐RNA titer, were predictive of HCC occurrence in cirrhosis in our clinical setting.
Mutational Analyses of Multiple Target Genes in Histologically Heterogeneous Gastric Cancer with Microsatellite Instability
Authors: Wang Ying , Shinmura Kazuya , Guo Rong‐Jun , Isogaki Jun , Wang Dong‐Yu , Kino Isamu , Sugimura Haruhiko
Published: August 2005

It has been recognized that gastric cancer often shows histological heterogeneity in a single tumor. Although microsatellite instability (MSI) has been reported in gastric cancer, the significance of genomic instability in gastric cancers with histological heterogeneity within a single tumor has never been addressed. We investigated MSI at 8 microsatellite loci in 40 normal/tumor DNA pairs from 20 gastric cancers with histological heterogeneity. Six of 20 patients (10 DNAs of 40 tumor DNAs) had severe MSI in more than 3 loci. Four of the MSI‐positive cases had frameshift mutations in the poly(A)10 tract of the TGFβRII gene. This mutation was found only in the MSI‐positive component in the 2 cases (cases 4 and 5) in which only 1 component exhibited MSI. The other 4 cases demonstrated homozygous or heteroclonal mutations (1 and 2 base deletions) in the poly(A)8 tract of the hMSH3 gene; no mutation was detected in the poly(C)8 tract of the hMSH6 gene in any of the MSI‐positive cases. The profile of alterations in multiple targets was different between the 2 components in most of the cases (5/6). These findings suggest that mismatch repair deficiency in MSI‐positive tumors causes multiple gene inactivations through frameshift mutations in short repetitive sequences in a heterogeneous way within a histologically heterogeneous tumor.
Expression of the SART‐1 Antigens in Uterine Cancers
Authors: Matsumoto Hajime , Shichijo Shigeki , Kawano Kouichiro , Nishida Takashi , Sakamoto Masaru , Itoh Kyogo
Published: August 2005

We recently reported that the SART‐1 gene, encoding the SART‐1259 tumor antigen which is recognized by HLA‐A26‐restricted cytotoxic T lymphocytes (CTLs), is expressed in the cytosol of squamous cell carcinomas and adenocarcinomas. The present study deals with the expression of SART‐1259 and SART‐1800 antigens in uterine cancers. The SART‐1259 antigen was detected in the cytosol fraction of 4 of 8 uterine cancer cell lines, 24 of 74 (32%) uterine cancer tissues, 0 of 7 uterine myomas, and 0 of 5 non‐tumorous uterine tissues. The SART‐1800 antigen was expressed in the nuclear fraction of all the uterine cancer cell lines, 41 of 74 (55%) uterine cancer tissues, 0 of 7 myomas, and 3 of 5 non‐tumorous uterine tissues. The SART‐1259+ uterine cancer cells were recognized by HLA‐A24 restricted and SART‐1 specific CTLs. Therefore, SART‐1259 antigen could be an appropriate vaccine candidate for a relatively large number of uterine cancer patients.
EAT/mcl‐1, a Member of the bcl‐2 Related Genes, Confers Resistance to Apoptosis Induced by cis‐Diammine Dichloroplatinum (II) via a p53‐Independent Pathway
Authors: Ando Takashi , Umezawa Akihiro , Suzuki Atsushi , Okita Hajime , Sano Makoto , Hiraoka Yoshiki , Aiso Sadakazu , Saruta Takao , Hata Jun‐ichi
Published: August 2005

EAT/mcl‐1 showed increased expression during the differentiation of a multipotent human embryonic carcinoma cell line, NCR‐G3, and of myeloblastic cells “ML‐1,” and has sequence similarity to Bcl‐2. In this present study, we determined whether the apoptotic cell death induced by chemo‐therapeutic agents could be inhibited by EAT/mcl‐1, as has been found with Bcl‐2. Cells transfected with EAT/mcl‐1 showed higher resistance to cis‐diammine dichloroplatinum (II) (CDDP) and carboplatin compared with the parental line (10)1 and neomycin‐resistance gene‐transfected clone, (10)1/neo. There was, however, no difference in sensitivity to etoposide, N, N‐bis‐(2‐chloroethyl)‐N′‐(3‐hydroxypropyl) phosphordiamidic acid cyclic ester monohydrate, adriamycin or other chemotherapeutic agents tested. DNA fragmentation of the parental cells following treatment with CDDP and carboplatin was observed in a concentration‐dependent manner. In contrast, cells transfected with EAT/mcl‐1 did not show DNA fragmentation following treatment with the same concentration of these drugs. EAT/mcl‐1 was capable of delaying the onset of p53‐independent apoptosis, although it could not inhibit apoptosis completely. Since CDDP and carboplatin damage DNA and then activate c‐abl and the JNK/SAPK pathway, EAT/mcl‐1 may inhibit p53‐independent apoptosis through a c‐abl/JNK (SAPK)‐dependent mechanism. EAT/mcl‐1 has functional homology to Bcl‐2 in that it can enhance cell viability under conditions which otherwise cause apoptosis and increase resistance to chemotherapeutic agents.
Schedule‐dependent and ‐independent Antitumor Activity of Paclitaxel‐based Combination Chemotherapy against M‐109 Murine Lung Carcinoma in vivo
Authors: Fujimoto Shuichi , Chikazawa Hirotaka
Published: August 2005

The established antitumor efficacy of paclitaxel against a variety of human tumors has led to pre‐clinical and clinical studies to develop the paclitaxel‐based combination regimens. We examined in vivo the antitumor activity and toxicity of the combination of paclitaxel and each of 8 antitumor agents, currently in clinical use, against M‐109 murine lung carcinoma implanted subcutaneously into male CDF1 mice. Paclitaxel given intravenously at 24 mg/kg/day on a schedule of consecutive daily injections for 5 days (d1–5) induced reproducibly, in 6 experiments, a significant (37–82%) increase in the survival time of tumor‐bearing mice over saline‐treated control mice. Cisplatin at 4 and 2 mg/kg/day given intravenously on the same treatment schedule showed no significant antitumor activity when given alone; however, the combination of paclitaxel at 24 mg/kg/day (d1–5) followed by cisplatin at a dose of 2 mg/kg/day (d6–10) induced a significant (P<0.05) prolongation of the survival time of tumor‐bearing mice compared with the group given paclitaxel alone. On the other hand, treatment with these drugs on the reverse sequence caused toxic deaths of all mice. Such sequence‐dependent toxic death of mice was also observed with the combination of paclitaxel and carboplatin, etoposide or methotrexate. The combination of paclitaxel and adriamycin, cyclophosphamide, ranimustine or vinblastine (VLB) showed a sequence‐independent antitumor activity and a more‐than‐additive therapeutic effect was observed with the combination of paclitaxel and either VLB or ranimustine. Although the drug administration schedules used here may not be directly applicable to the clinic, knowledge of the nature of the sequence‐dependency in paclitaxel‐based combination chemotherapy should be useful in the design of clinical trials.
Effect of Electroporation on Cell Killing by Boron Neutron Capture Therapy Using Borocaptate Sodium (10B‐BSH)
Authors: Ono Koji , Kinashi Yuko , Masunaga Shin‐ichiro , Suzuki Minoru , Takagaki Masao
Published: August 2005

The cell membrane permeability of 10B‐enriched borocaptate sodium (BSH) and the extent to which BSH is accumulated in cells are controversial. To elucidate these points and to enhance the accumulation of BSH in cells, the effect of electroporation on boron neutron capture therapy (BNCT) using BSH was investigated. The first group of SCCVII tumor cells was incubated in culture medium with 10B‐BSH or 10B‐enriched boric acid, and exposed to neutrons from the heavy water facility of the Kyoto University Reactor. More than 99% of neutrons were thermal neutrons at flux base. The second group was pretreated with electroporation in combination with 10B‐BSH, and thereafter the cells were irradiated with neutrons. The cell‐killing effect of BNCT was measured by colony formation assay. The surviving cell fraction decreased exponentially with neutron fluence, and addition of BSH significantly enhanced the cell‐killing effect of NCT depending on 10B concentration and the preincubation time of cells in the BSH‐containing culture medium. The electroporation of cells with BSH markedly enhanced the BNCT effect in comparison with that obtained with preincubation alone. The effect of BSH‐BNCT with electroporation was almost equal to that of BNCT using 10B‐boric acid at the same 10B concentration. The effect of BNCT on cells pretreated with BSH and electroporation was not reduced by repeated washing of the cells before neutron irradiation. Decrease of the effect of BSH‐BNCT plus electroporation with increase in the waiting time between the electroporation and the neutron irradiation could be explained in terms of the extent of cell growth during that time. These data suggest that BSH penetrates the cells slowly and remains after washing. Electroporation can introduce BSH into the cells very efficiently, and BSH thus introduced stays in the cells and is not lost in spite of the intensive washing of the cells. Therefore, if electroporation is applied to tumors after BSH injection, 10B would remain in the tumors but be cleared from normal tissues, and selective accumulation of 10B in tumors will be achieved after an appropriate waiting time.
Induction of Glandular Stomach Cancers in Helicobacter pylori‐sensitive Mongolian Gerbils Treated with N‐Methyl‐N‐nitrosourea and N‐Methyl‐N′‐nitro‐N‐nitrosoguanidine in Drinking Water
Authors: Tatematsu Masae , Yamamoto Masami , Shimizu Nobuyuki , Yoshikawa Akemi , Fukami Hiroko , Kaminishi Michio , Oohara Takeshi , Sugiyama Atsushi , Ikeno Tatsuo
Published: August 2005

An animal model of stomach carcinogenesis was established using Mongolian gerbils with N‐methyl‐N‐nitrosourea (MNU) and N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG) as the carcinogens. In addition, the sensitivity of these gerbils to Helicobacter pylori (H. pylori) was confirmed. One hundred and sixty specific pathogen‐free male MGS/Sea animals, 7 weeks old, were treated with MNU in the drinking water (30 ppm for alternate weeks to give 10 weeks exposure, or 10 ppm or 3 ppm for 20 weeks continuous exposure), or given MNNG in the drinking water at 400 ppm or 200 ppm for 20 weeks, or orally inoculated with ATCC43504 H. pylori (1.7×1088 CFUs/animal). Adenocarcinomas in the glandular stomach were found in 2 out of 12 effective animals (2/12) treated with 30 ppm MNU at week 20, although all were dead or moribund by week 30 due to MNU toxicity. At week 50, the incidences of gastric adenocarcinomas in groups treated with 10 ppm MNU, 3 ppm MNU, 400 ppm MNNG, and 200 ppm MNNG were 2/21 (9.5%), 1/23 (4.3%), 7/11 (63.6%), and 1/10 (10.0%). The lesions were generally well differentiated, although poorly differentiated adenocarcinoma was also found in a single gerbil in each of the 10 ppm MNU and 400 ppm MNNG groups. In control animals no tumors were found. In the infection study, the animals were killed at week 20, and H. pylori was detected in all cases, causing multiple erosions with marked inflammatory cell infiltration in the lamina propria and submucosa, and frequent formation of lymphoid follicles. Thus, MNU and MNNG in the drinking water induced neoplastic lesions in the glandular stomach epithelium of H. pylori‐sensitive gerbils.
Induction of Squamous Cell Carcinomas in the Salivary Glands of Rats by Potassium Iodide
Authors: Takegawa Kiyoshi , Mitsumori Kunitoshi , Onodera Hiroshi , Yasuhara Kazuo , Kitaura Keisuke , Shimo Takeo , Takahashi Michihito
Published: August 2005

In a 2‐year carcinogenicity study of potassium iodide (KI) in F344/DuCrj rats, squamous cell carcinomas (SCCs) were observed in the salivary glands of 4/40 males and 3/40 females receiving 1000 ppm KI in the drinking water. Ductular proliferation with lobular atrophy was observed at high incidence in the submandibular glands of the high‐dose animals, and squamous metaplasia was frequently evident within the proliferative ductules and the larger interlobular ducts. A transition from metaplasia to SCC was apparent. The results suggest that squamous metaplasia in proliferative ductules, occurring secondarily to lobular impairment induced by KI, may develop into SCCs via a non‐genotoxic, proliferation‐dependent mechanism.
Up‐regulation of p27Kip1 Correlates Inversely with Anchorage‐independent Growth of Human Cancer Cell Lines
Authors: Kawada Manabu , Uehara Yoshimasa , Mizuno Satoshi , Yamori Takao , Tsuruo Takashi
Published: August 2005

We examined the correlation between anchorage‐independent growth and cell cycle‐related molecules using 39 human cancer cell lines. They consisted of lung‐, colon‐, stomach‐, breast‐, ovarian‐, brain‐, renal‐ and melanoma‐derived cell lines. Their anchorage‐independent growth ability varied, but was not clearly related to the tissue of origin. There was a tendency for the levels of cyclin D1, cyclin E, cyclin A, p27, and p21 to show a tissue‐dependent expression pattern. Statistical analysis revealed an inverse correlation of the p27 level with anchorage‐independent growth (r=−0.456, P<0.01). Thus, the regulation of p27 is suggested to be linked to the anchorage independence of human cancer cells.
Risk Factors for Benign Breast Disease according to Histopathological Type: Comparisons with Risk Factors for Breast Cancer
Authors: Minami Yuko , Ohuchi Noriaki , Taeda Yoshinori , Fukao Akira , Hisamichi Shigeru
Published: August 2005

We evaluated risk factors for benign breast disease by using a case‐control study method. The series was taken from participants in breast cancer screening programs during 1978–1986 in Miyagi Prefecture, Japan. All benign breast lesions diagnosed during this period were reviewed and reclassified into proliferative and non‐proliferative types based on the Dupont and Page classification. Data on 382 benign breast disease cases (130 proliferative‐type cases and 252 non‐proliferative‐type cases) and 1,489 screening year‐, age‐ and screening area‐matched normal controls were used for analysis. Nulliparity or low parity and family history of breast cancer in mother or sisters were significantly associated with an increased risk of proliferative type. Premenopausal status was significantly associated with an increased risk of non‐proliferative type. No significant association with history of lactation for the last child was observed in either type, but the risk of proliferative type increased with increasing duration of lactation (P=0.08). A comparison between the present findings and the risk factors for breast cancer indicated epidemiologic similarities between proliferative benign and malignant breast lesions in general. The associations of these two lesions with lactation patterns were, however, dissimilar.
Chemoprevention of N‐Nitroso‐N‐methylurea‐induced Rat Mammary Carcinogenesis by Soy Foods or Biochanin A
Authors: Gotoh Takahiko , Yamada Kazumasa , Yin Hong , Ito Akihiro , Kataoka Tsuyoshi , Dohi Kiyohiko
Published: August 2005

We examined the effects of soybeans, a soy product (miso) and biochanin A, an isoflavone derivative, on N‐nitroso‐N‐methylurea (MNU)‐induced rat mammary carcinogenesis. Seven‐week‐old female CD/Crj rats received a single i.v. dose (40 mg/kg body weight) of MNU. After administration of MNU, rats were fed diet containing 0% (control), 2% or 10% soybeans, or 10% miso as a soy‐supplemented diet, or 10 or 50 mg/kg biochanin A. All rats were observed for 18 weeks after MNU administration. At 18 weeks, the multiplicity (mean tumors/rat) of palpable mammary tumors was significantly decreased in the 10% soybean (1.1) and 10% miso (1.2) diet groups compared to the control (2.2) (P<0.05, respectively). In the biochanin A‐supplemented diet groups, the incidence (percentage of rats with tumors) was significantly decreased in the 50 mg/kg (32%) diet group compared to the control (80%) (P<0.01), and the multiplicity was significantly decreased in both the 10 mg/kg (0.7) and 50 mg/kg (0.5) diet groups compared to the control (2.2) (P<0.01 and P<0.001, respectively). The proliferative cell nuclear antigen labeling index of mammary tumors was significantly decreased in both biochanin A‐supplemented diet groups compared to the control. The present results indicate that soybeans, miso, and biochanin A are useful for the prevention of mammary cancer.
Globotriaosyl Ceramide and Globoside as Major Glycolipid Components of Fibroblasts in Scirrhous Gastric Carcinoma Tissues
Authors: Sawada Ryugo , Hotta Hisako , Chung Yong‐Suk , Sowa Michio , Tai Tadashi , Yano Ikuya
Published: August 2005

Scirrhous gastric cancer is characteristic in that cancer cells proliferate and invade with prominent fibrosis. To search for the expression of specific carbohydrate chains in scirrhous gastric cancer, we have examined the glycosphingolipid composition of scirrhous cancer tissues (n=10) in comparison with that of non‐scirrhous cancer tissues (n=10) by means of two‐dimensional thin layer chromatography, followed by fast atom bombardment mass spectrometry of the individual glycolipids and immunostaining analysis. The major neutral glycosphingolipids from scirrhous gastric cancer tissues were identified as ceramide monohexoside, ceramide dihexoside, globotriaosyl ceramide (Gb3) and globoside (Gb4), while the major acidic glycosphingolipids were II3 Neu‐Acα‐LacCer, II3 NeuAcα2‐LacCer and sulfatide. Relative concentrations of Gb3 and Gb4 in scirrhous gastric cancer tissues (Gb3+ Gb4=58%) were two times higher than those in non‐scirrhous gastric cancer tissues (29%). Orthotopic fibroblasts cloned from scirrhous gastric cancer tissues showed similar high concentrations of Gb3 and Gb4 to scirrhous gastric cancer tissues. Furthermore, immunohistochemical study revealed that Gb3 and Gb4 were expressed intensely on the fibroblasts. On the other hand, analysis of glycosphingolipids in four scirrhous gastric cancer cell lines yielded the following results. i) The contents of Gb3 and Gb4 were low (6%), compared with orthotopic fibroblasts (62%). ii) Significant amounts of Lea (pentaglycosylceramide) and Leb (hexa‐ and heptaglycosylceramides), which could not be detected in scirrhous cancer tissues, were observed. The results show that the major neutral glycosphingolipids such as Gb3 and Gb4 of scirrhous gastric cancer tissues were derived from orthotopic fibroblasts and not from the cancer cells.
Increased Expression of Sucrase and Intestinal‐type Alkaline Phosphatase in Human Gastric Carcinomas with Progression
Authors: Nakamura Wataru , Inada Ken‐ichi , Hirano Kazuyuki , Tsukamoto Tetsuya , Inoue Hanae , Kito Kuniyoshi , Yoshikawa Akemi , Nakamura Shigeo , Tatematsu Masae
Published: August 2005

The activities of sucrase, total alkaline phosphatase (total ALP) and intestinal‐type alkaline phosphatase (I‐ALP) were assayed in gastric carcinomas and in their surrounding mucosae from 57 patients with advanced cancers, and the localization of sucrase in 203 carcinomas, including 86 early cancers, was examined immunohistochemically using polyclonal anti‐sucrase antibody. All three enzymes were active in the 57 carcinomas as well as in their surrounding mucosae, but the levels were fairly low as compared to those in normal jejunum mucosa. A considerable part of the total ALP activity in tumor specimens was assumed to be due to I‐ALP itself. Increased sucrase and I‐ALP were found with greater depth of invasion by undifferentiated‐type carcinomas. The pattern of immunohistochemical localization of sucrase in the 203 carcinomas also clearly indicated increased expression with greater depth of invasion even in differentiated‐type carcinomas.
Effects of Interleukin‐12 on the Induction of Cytotoxic T Lymphocytes from the Regional Lymph Node Lymphocytes of Patients with Lung Adenocarcinoma
Authors: Hanagiri Takeshi , Yoshino Ichiro , Takenoyama Mitsuhiro , So Tomoko , Fujie Hiroshi , Imabayashi Satoru , Eifuku Ryozo , Yoshimatsu Takashi , Osaki Toshihiro , Nakanishi Ryoichi , Ichiyoshi Yuji , Nagashima Akira , Nomoto Kikuo , Yasumoto Kosei
Published: August 2005

Lung cancer‐specific cytotoxic T lymphocytes (CTL) were induced by repeated stimulations of regional lymph node lymphocytes (RLNL) in lung cancer patients with either autologous or HLA‐A‐locus‐matched tumor cells. To investigate the effect of interleukin‐12 (IL‐12), IL‐12 was added during the stimulation of RLNL from HLA A24 / adenocarcinoma patients with either autologous tumor cells or HLA A24‐positive adenocarcinoma cells (PC‐9) in combination with, or instead of interleukin‐2 (IL‐2), and then the cytotoxic activity, cytokine production and populations of the lymphocyte subsets were examined. The addition of IL‐12, or the substitution of IL‐2 by IL‐12 was found to enhance the cytotoxic activity and the cytokine production (IFN‐γ, GM‐CSF) of the CTL as compared with IL‐2 alone. The cytotoxic activity and cytokine production were both partially inhibited by anti‐MHC‐class I monoclonal antibody. The CTL thus induced by IL‐12 had a higher proportion of CD3+/CD56+ cells than the CTL induced with IL‐2 alone. The positively selected CD8+/CD56– lymphocytes showed PC‐9‐specific cytotoxic activity, because the population did not show any cytotoxicity to K562 or A549 (HLA‐A26/A30). However, the CD3+/CD56+ lymphocytes were cytotoxic to both PC‐9 and K562. In conclusion, IL‐12 is considered to be a useful cytokine for both the induction of lung‐cancer specific CTL and the augmentation of non‐MHC‐restricted cytotoxicity against tumor cells, and may be applicable for adoptive immunotherapy using CTL.
Absence of p53 Overexpression and Favorable Response to Cisplatin‐based Neoadjuvant Chemotherapy in Urothelial Carcinomas
Authors: Kakehi Yoshiyuki , Özdemir Enver , Habuchi Tomonori , Yamabe Hirohiko , Hashimura Takayuki , Katsura Yoshitaka , Yoshida Osamu
Published: August 2005

It has been controversial whether cancer cells harboring loss or inactivation of the tumor suppressor p53 are resistant or sensitive to DNA‐damaging agents including cisplatin and doxorubicin. Overexpression of mdm2 oncoprotein, a negative regulator of p53, is assumed to be an alternative to p53 dysfunction. Archival urothelial carcinoma specimens obtained from 60 patients prior to cisplatin‐based chemotherapy were immunohistochemically studied for overexpression of p53 and mdm2. Thirty‐two patients (group I) were treated with chemotherapy in the neoadjuvant setting, while 28 patients (group II) underwent chemotherapy for distant metastases or inoperable locoregional tumors. In group I, the responsiveness was correlated with staining status of p53 (P=0.0225) and the combination of p53 and mdm2 (P=0.0497). Negative staining of p53 and negative for both p53 and mdm2 could have predicted favorable response to chemotherapy in 16 of 18 (88.9%) and in 12 of 13 (92.3%) tumors, respectively. On the other hand, p53‐positive and p53 and/or mdm2‐positive staining could have predicted poor response only in 7 of 14 (50.0%) and 8 of 19 (42.1%) tumors, respectively. Disease‐specific survival of the p53‐negative group was significantly superior to that of the p53‐positive group (P=0.0086). Difference in survival did not become more significant when overexpression of mdm2 was taken into consideration (P=0.0456). In contrast, in group II, there was no correlation of responsiveness to chemotherapy or survival with p53‐ or p53/mdm2‐staining status. The patients with urothelial carcinomas negative for overexpression of p53 will benefit from neoadjuvant chemotherapy. From clinical viewpoint, however, p53 status alone or the combination of p53 and mdm2 status is not enough to identify those patients who will not benefit from the treatment.
1‐Methyl‐3‐propyl‐7‐butylxanthine, a Novel Biochemical Modulator, Enhances Therapeutic Efficacy of Adriamycin
Authors: Sadzuka Yasuyuki , Iwazaki Ayano , Sugiyama Tomomi , Sawanishi Takayuki , Miyamoto Ken‐ichi
Published: August 2005

We have screened xanthine derivatives for activity as novel biochemical modulators by assay of their inhibitory effect on adriamycin efflux from tumor cells. Strong inhibition of adriamycin efflux was shown by some xanthine derivatives with various alkyl or oxoalkyl substituents at the 1‐, 3‐ and 7‐positions. 1‐Methyl‐3‐propyl‐7‐butylxanthine (XT‐77), which had the greatest inhibitory effect on adriamycin efflux in vitro among the compounds tested, potentiated adriamycin‐induced antitumor activity by causing an increase of adriamycin concentration in the tumor in vitro. Furthermore, XT‐77 reduced the adverse drug reactions of adriamycin by decreasing the adriamycin concentrations in the heart and the liver. Thus, the combination of XT‐77 with adriamycin not only increased the antitumor activity of adriamycin, but also decreased the adverse drug reactions.
Establishment of Epstein‐Barr Virus‐positive Human Gastric Epithelial Cell Lines
Authors: Tajima Masako , Komuro Masato , Okinaga Kota
Published: August 2005

We have established two Epstein‐Barr virus (EBV)‐positive cell lines, GT38 and GT39, derived from human gastric tissues of two patients bearing gastric carcinoma. Both cell lines were positive for cytokeratin, an epithelial marker, but not for lymphocyte‐related markers. Unlike GT39 cell line, GT38 cells lacked the property of contact inhibition. EBV genome was detected in both cell lines. The cell lines were positive for latent membrane protein 1, and EBV‐determined nuclear antigen 1 (EBNA1). EBNA2 was also detected in GT38. These cell lines should be useful for studying the interaction of EBV with gastric epithelial cells and its role in gastric carcinogenesis.
CD44 Variant Isoform Expression and Breast Cancer Prognosis
Authors: Tokue Yutaka , Matsumura Yasuhiro , Katsumata Noriyuki , Watanabe Toru , Tarin David , Kakizoe Tadao
Published: August 2005

We examined the expression of CD44 isoforms in samples of breast cancer tissues from 95 patients by reverse transcription‐polymerase chain reaction and immunohistochemistry, and tried to correlate the results with survival period. At the RNA level, expression of exon v2 was observed in 33 (35%) and that of v6 in 69 (73%) of the 95 specimens. Patients with CD44v2 mRNA expression had significantly shorter survival times than those with v2‐negative tumors (P=0.05), but there was only a weak correlation, if any, between v6 mRNA expression and overall survival (P=0.06). Tumor tissue from 22 (23%) and 72 (76%) patients showed positive immunoreactivity with monoclonal antibody (mAb) M23.6.1. (CD44v2) and mAb 2F10 (CD44v6), respectively. Immunohistochemical evidence of CD44v2 peptide expression correlated with overall survival (P=0.02), but there was no such association with CD44v6 expression in these tumors (P=0.67). There were significant correlations between v2 immunoreactivity and higher histological grade and lower levels of estrogen and progesterone receptor. There was no significant correlation between v6 immunoreactivity and such clinicopathological characteristics. Although the expression of v2 was significantly associated with reduced overall survival, it was not an independent prognostic factor because it also correlated with progesterone receptor status. These findings suggest that v2 isoform expression might have more value than v6 expression for clinical use.
Up‐regulation of CD44 Variant Exon Expression in Endometrial Carcinomas: Analysis of mRNA and Protein Isoforms, and Relation to Clinicopathological Factors
Authors: Saegusa Makoto , Okayasu Isao
Published: August 2005

In order to clarify the relation between expression of individual CD44 variant exons and tumor progression, 34 endometrial carcinomas (endometrioid type) were investigated, as well as 27 samples of normal endometrium, using a combination of reverse transcription‐polymerase chain reaction (RT‐PCR) and Southern blot hybridization (SBH). Western blotting was also performed for comparison of protein levels with the results of the RT‐PCR/SBH methods. Analysis of gross CD44 splicing patterns demonstrated high‐level expression of variant isoforms in endometrial carcinomas as compared with normal endometrium. Exon‐specific RT‐PCR/SBH assays revealed large, abundant transcripts of individual variant exons, in particular v3, v4, and v5, in tumors, but these isoforms were also expressed in normal endometria, suggesting a lack of tumor‐specificity. No individual CD44 variant transcripts were associated with any of the prognostic factors investigated. Parallel observations showed variant CD44 transcripts to be more readily detectable than protein isoforms in the same samples. These findings indicate that in endometrial carcinomas, expression of individual variant CD44 exons is markedly up‐regulated, but this molecule may not be useful as a consistent indicator of tumor progression.
Genetic Alterations of Mixed Hyperplastic Adenomatous Polyps in the Colon and Rectum
Authors: Uchida Hiroyuki , Ando Hiroshi , Maruyama Keiji , Kobayashi Hiroshi , Toda Hiroshi , Ogawa Hiroshi , Ozawa Takachika , Matsuda Yasuhide , Sugimura Haruhiko , Kanno Takashi , Baba Shozo
Published: August 2005

Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K‐ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K‐ras. No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K‐ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs.
Increased Sensitivity to Long‐term 5‐Fluorouracil Exposure of Human Colon Cancer HT‐29 Cells Resistant to Short‐term Exposure
Authors: Inaba Makoto , Tanaka Tomoko , Sawada Hiroko
Published: August 2005

A 5‐fluorouracil (5‐FU)‐resistant subline of human colon cancer HT‐29 cells was developed by repeated 1‐h exposure in vitro to 5‐FU. This subline (HT‐29/5‐FU/S) had 8‐fold resistance to 5‐FU in a 1‐h exposure assay. However, it had rather increased sensitivity to 5‐FU when assayed after a continuous 96‐h exposure to it. Significantly less 5‐fluorouridine‐5′‐triphosphate was produced in the resistant cells, leading to a lower level of 5‐FU incorporation into the cellular RNA. The reduced activity of orotate phosphoribosyltransferase might explain these results. In contrast, the HT‐29/5‐FU/S cells were more sensitive to the inhibition of in situ thymidylate synthase (TS) by 5‐FU than were the parent cells. The lower in situ TS activity may have made HT‐29/5‐FU/S cells more sensitive to TS inhibition by 5‐FU as compared with the parent cells. The fact that HT‐29/5‐FU/S was more resistant to short‐term 5‐FU exposure but more sensitive to long‐term exposure than the parent line confirmed the existence of different modes of action of 5‐FU, depending on the exposure time.
Molecular Analysis of a Myc Antagonist, ROX/Mnt, at 17p13.3 in Human Lung Cancers
Authors: Takahashi Takao , Konishi Hiroyuki , Kozaki Ken‐ichi , Osada Hirotaka , Saji Shigetoyo , Takahashi Toshitada , Takahashi Takashi
Published: August 2005

The chromosome region 17p13 is known to be frequently deleted in lung cancers. We recently showed the presence of an independent, commonly deleted region at 17p13.3, suggesting that in addition to p53 at 17p13.1 an as‐yet‐unidentified tumor suppressor gene may reside in this telomeric region. Interestingly, the chromosomal location of a recently isolated novel myc antagonist gene, termed ROX/Mnt, coincides exactly with the centromeric border of the commonly deleted region at 17p13.3 in lung cancers. In conjunction with the generally acknowledged roles of myc genes in the pathogenesis of lung cancers, these findings led us to investigate whether ROX/Mnt is altered in lung cancers. Despite an extensive search for alterations in 52 lung cancer specimens, somatic mutations of ROX/Mnt could not be identified. We conclude that ROX/Mnt itself is not a frequent target for 17p13.3 deletions in lung cancers and that further explorations are required to identify the putative tumor suppressor gene at 17p13.3.
Improvement of Transduction Efficiency of Recombinant Adeno‐associated Virus Vector by Entrapment in Multilamellar Liposomes
Authors: Mizuno Masaaki , Yoshida Jun
Published: August 2005

Recombinant adeno‐associated virus (AAV) has attracted considerable interest as a potential vector for human gene therapy, but its transduction efficiency is quite low. The present study demonstrated AAV vector‐associated liposomes to be more effective for in vitro gene transfer to human glioma cells than are liposomes containing plasmid DNA. Using vector‐associated liposomes increased the transduction efficiency more than 10‐fold compared to liposomes containing plasmid DNA and more than 6‐fold compared to AAV alone. From these results, AAV vector‐associated liposomes appear to be a good candidate for in vivo gene delivery to human gliomas.
Inhibitory Effects of Curcumin and Tetrahydrocurcuminoids on the Tumor Promoter‐induced Reactive Oxygen Species Generation in Leukocytes in vitro and in vivo
Authors: Nakamura Yoshimasa , Ohto Yoshimi , Murakami Akira , Osawa Toshihiko , Ohigashi Hajime
Published: August 2005

The inhibitory effects of curcumin and two tetrahydrocurcuminoids on tumor promoter‐induced oxidative stress in vitro and in vivo were investigated. Curcumin, tetrahydrocurcumin (THC) and dihydroxytetrahydrocurcumin (DHTHC) exhibited significant inhibitory effects on 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA)‐induced O2‐generation in differentiated HL‐60 cells. The inhibitory activity of THC was weaker than that of curcumin. This tendency was the inverse of the results of previous studies on in vitro antioxidative activity against lipid peroxidation. The curcuminoids inhibited TPA‐induced intracellular peroxide formation in differentiated HL‐60 cells. THC exhibited much weaker inhibition of intracellular peroxide formation than curcumin, suggesting that this inhibition might be attributable to the inhibition of O2‐generation. The inhibitory effects of curcuminoids on TPA‐induced H2O2 formation in female ICR mouse skin were further examined using the double‐TPA‐application model. Each TPA application induces two distinct biochemical events, 1) recruitment of inflammatory cells to the inflammatory regions and 2) activation of oxidant‐producing cells. Double pretreatment of mice with curcuminoids before each TPA treatment significantly suppressed double TPA application‐induced H2O2 formation in the mouse skin. Coadministrations of curcumin with either first or second TPA treatment significantly inhibited H2O2 formation. In addition, THC tends to show weaker inhibitory activities than curcumin in bioassays related to tumor promotion, i.e., inhibition of tumor promoter‐induced inflammation in mouse skin and Epstein‐Barr virus activation. These tendencies were parallel to those in the tumor‐suppressive potential of curcumin and THC in mouse skin, as previously reported. Thus, we concluded that curcuminoids significantly suppress TPA‐induced oxidative stress via both interference with infiltration of leukocytes into the inflammatory regions and inhibition of their activation.