bluuebunny/crossref_metadata_2025 huggingface dataset:
Low Glutathione and Glutathione S‐Transferase Levels in Barrett's Esophagus as Compared to Normal Esophageal Epithelium
Authors: van Lieshout Esther M. M. , Tiemessen Dorien M. , Witteman Ben J. M. , Jansen Jan B. M. J. , Peters Wilbert H. M.
Published: August 2005

Patients with Barrett's esophagus, wherein squamous epithelium has been replaced by columnar epithelium, have an increased risk for developing esophageal adenocarcinoma as compared to the general population. Glutathione S‐transferase (GST), a family of detoxification enzymes consisting of class α, μ, π, and θ isoforms, is involved in detoxification of carcinogens and low levels of these enzymes correlated with high cancer risk. We have now compared GST enzyme activity, GST isoenzyme composition and glutathione (GSH) content of Barrett's mucosa with that of adjacent normal squamous epithelium. Biopsy specimens of 98 patients with Barrett's esophagus were taken from both Barrett's and adjacent normal squamous epithelium. GST enzyme activity towards 1–chloro‐2,4–dinitrobenzene was measured, and GST isoenzyme levels were determined by densitometrical analyses of western blots after immunodetection with monoclonal antibodies. Total GSH content was determined by high‐performance liquid chromatography after conjugation with monobromobimane. Wilcoxon's signed rank test and Spearman correlation analyses were used for statistical evaluation. As compared with adjacent normal squamous epithelium, GST enzyme activity in Barrett's epithelium was reduced by 35%, and GST μ, GST π and GSH levels were reduced by 24%, 30%, and 63%, respectively. However, the minor GST α and GST θ levels were higher in Barrett's epithelium (by 625% and 33%, respectively). High levels of GSH and GSTs in general are correlated with protection against cellular or cytogenetic damage. The observed reduction in GSTs and GSH in Barrett's epithelium may therefore contribute to the increased cancer risk in this tissue.
Differential Regulation of MMP‐9 and TIMP‐2 Expression in Malignant Melanoma Developed in Metallothionein/RET Transgenic Mice
Authors: Asai Masami , Kato Masashi , Asai Naoya , Iwashita Toshihide , Murakami Hideki , Kawai Kumi , Nakashima Izumi , Takahashi1 Masahide
Published: August 2005

We recently established a metallothionein‐I(MT)/RET transgenic mouse line in which skin melanosis, benign melanocytic tumor and malignant melanoma develop stepwise. Malignant melanoma cells but not benign melanocytic tumor cells had metastatic ability in transgenic mice. In the present study, we investigated the expression of several matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs), including MMP‐1, MMP‐2, MMP‐3, MMP‐7, MMP‐9, MT1– MMP, TIMP‐1 and TIMP‐2, in these tumors. Western and northern blot analyses revealed that malignant transformation of melanocytic tumors developed in MT/RET transgenic mice accompanied with upregulation of MMP‐9 and downregulation of TIMP‐2. Expression of other MMP and TIMP genes examined was very low or undetectable in both benign and malignant tumors. Since activation of MMP‐9 in malignant tumors was detected by gelatin zymography, these results suggest that imbalance of expression of the MMP‐9 and TIMP‐2 genes might be associated with metastatic ability of melanoma cells developed in MT/RET transgenic mice.
Viral Hepatitis and Hepatocellular Carcinoma Prevention Strategy in Japan
Authors: Oda Toshitsugu
Published: August 2005

The study of human hepatitis, particularly in Asia, where the incidence rate has been the highest in the world, has contributed greatly to the understanding of carcinogenesis of the liver and related diseases. In this article, the history of research on hepatitis viruses and hepatocellular carcinoma (HCC) and the successful prevention of vertical transmission of hepatitis B virus (HBV) in Japan are reviewed, focusing on the studies that resulted in the identification of vertical transmission of HBV infection and the association of HBV‐sustained infection and HCC. The vaccination trials for preventing HBV vertical transmission and the fruitful outcome of the nationwide vaccination strategy in Japan, on the basis of‘'selective'’immunization by using anti‐HBs immunoglobulin (HBIG) and HB vaccine, are highlighted. Ongoing studies on the mechanisms underlying hepatocarcinogenesis induced by viruses, e.g., the roles of viral proteins and inflammation, are also reviewed, and prospects for the control of HCC are discussed.
Chronic Active Disease Reflects Cancer Risk in Ulcerative Colitis
Authors: Shinozaki Masaru , Muto Tetsuichiro , Suzuki Kimitaka , Matsuda Keiji , Yokoyama Tadashi , Watanabe Toshiaki , Masaki Tadahiko , Sato Hajime , Araki Shunichi , Nagawa Hirokazu
Published: August 2005

There is an increased risk of developing colorectal neoplasia in ulcerative colitis (UC) and surveillance colonoscopy is recommended for early detection. We investigated the precise features of UC retrospectively to identify a subgroup with longstanding extensive UC at increased risk of neoplasia. From 1985 to August 1997, we experienced eight UC patients with colorectal cancer and eight with definite dysplasia. All 16 had extensive disease of seven years or more in duration. During the same period, 61 of 334 UC patients without colorectal neoplasia were available for detailed study, allowing evaluation of non‐surgical patients with extensive colitis of seven years or more in duration. Basic clinical factors including family history of cancer, expressions of disease activity and durations of pharmacotherapy were investigated. Univariate analysis revealed four significant factors: intractability (P=0.001), periods of inflammation persisting for 3 months or more (P<0.01) and total durations of diarrhea (P<0.01) and hematochezia (P<0.05). The number of admissions and the duration of systemic steroid administration were higher in the neoplasia group but without statistical significance. Multivariate analysis revealed two significant factors: duration of diarrhea (P<0.001) and age at onset (P<0.01). Chronic active disease is a risk factor for colorectal cancer or dysplasia in extensive and longstanding UC.
Characterization of the MEN1 Gene Product, Menin, by Site‐specific Polyclonal Antibodies
Authors: Ikeo Yasuto , Sakurai Akihiro , Hashizume Kiyoshi
Published: August 2005

The gene associated with multiple endocrine neoplasia type 1 (MEN 1), designated MEN1, has recently been identified. This gene shows no homology to other known genes, and its expression is not restricted to endocrine organs as estimated by northern blotting. Expression of the MEN1 gene product, menin, has been studied only in a few tissues. In this report, expression of menin in various cells and mouse tissues was studied using two polyclonal antibodies against menin. Expression of menin as a 76 kDa single protein was observed in all cell lines examined, regardless of origin. Two nuclear localization signals of the menin have been reported, but through the study of mutant menin in lymphocytes from subjects with MEN 1, impaired nuclear localization of the mutant menin was observed even though the mutant retained one of the two nuclear localization signals (NLSs). Menin was stable in vitro with a half‐life of over 24 h at 37°C. In the cell, the half‐life of wild‐type menin was about 10 h, while that of the mutant was about 2 h. The mutant rapidly disappeared from the nucleus.
Detection of Methylation Damage in DNA of Gastric Cancer Tissues Using 32P‐Postlabelling Assay
Authors: Kim Dae‐Yong , Cho Myung‐Haing , Yang Han‐Kwang , Hemminki Kari , Kim Jin‐Pok , Jang Ja‐June , Kumar Rajiv
Published: August 2005

Gastric cancer is the most common cancer in Korea. The causes are still unknown but it has been speculated that gastric cancer is associated with consumption of foods rich in nitrates/nitrites or a high dietary intake of salt or pickled food. In the present study, we studied the level of alkylated DNA adducts formed in gastric cancer tissues in comparison with that in normal gastric mucosa. DNA was extracted from surgically removed gastric cancer tissues and patient‐matched normal gastric mucosa. The level of N7‐methyldeoxyguanosine was measured by 32P‐postlabelling assay after high performance liquid chromatography (HPLC) enrichment. We found that the level of N7‐methyldeoxyguanosine of gastric cancerous tissues was significantly higher than that of normal gastric mucosa (P=0.01685).
Morphology, Proliferation and Apoptosis of Mouse Liver Epithelial Cells Cultured as Spheroids
Authors: Lee Gang‐Hong , Osanai Makoto , Tokusashi Yoshihiko
Published: August 2005

The MLEC10 is an epithelial cell line derived from an untreated, normal C3H/HeN mouse liver. We previously demonstrated that tumorigenic variants from this cell line produced moderately differentiated hepatocellular carcinomas in nude mice. However, it has remained unclear whether the parental MLEC10 cells represent immortalized hepatocytes or so‐called oval cells, both of which may serve as precursors for hepatocellular neoplasms. In this study, we performed 3‐dimensional, spheroid culture of the MLEC10 cells in order to facilitate histological assessment of their lineage. Spheroidal aggregates were formalin‐fixed and embedded in paraffin for routine light‐microscopic observation of hematoxylin and eosin‐stained sections. Histopathologically, the MLEC10 cells were indistinguishable from immature hepatocytes and distinct from oval cells. At the electron‐microscopic level, their hepatocytic nature was evidenced by bile canaliculus structures and glycogen storage. Intriguingly, the spheroids contained fragmentary material reminiscent of Councilman bodies, implying apoptosis of the hepatocytes. Although the cells significantly proliferated during the first three days of culture, apoptotic death then resulted in a 75 % decrease in viable cell number. Thereafter, both apoptosis and cell division appeared silent, the numbers being unchanged. Expression of the p53 tumor suppressor gene became gradually elevated, correlating positively with growth arrest, but negatively with apoptosis, suggesting that the cell death occurred independently of p53. Our results indicate that at least some liver epithelial cell lines derived from untreated murine livers exhibit a hepatocytic morphology in spheroid culture. Also, the present culture system provides a useful tool for investigating biological phenomena, e.g. apoptosis, specifically involving liver cells, under 3‐dimensional conditions.
In vivo Anti‐tumor Activity of a Novel Indolocarbazole Compound, J‐107088, on Murine and Human Tumors Transplanted into Mice
Authors: Arakawa Hiroharu , Morita Masashi , Kodera Tsutomu , Okura Akira , Ohkubo Mitsuru , Morishima Hajime , Nishimura Susumu
Published: August 2005

J‐107088 (6‐N‐(1‐hydroxymethyl‐2‐hydroxy)ethylamino‐12,13‐dihydro‐2,10‐dihydroxy‐13‐(β‐D‐glu‐copyranosyl)‐5H‐indolo[2,3‐a]‐pyrrolo [3,4‐c]carbazole‐5,7(6H)‐dione) is a derivative of NB‐506, an indolocarbazole compound previously reported as an anti‐tumor agent targeting topoisomerase L The optimal administration schedule of J‐107088 was found to be intermittent injections. The GID75 (75% growth inhibiting total dose) values of J‐107088 against LX‐1 lung cancer and PC‐3 prostate cancer when given by intermittent injection (twice a week for 2 consecutive weeks) were 200 and 15 mg/m2, respectively, whereas the 10% lethal dose (LD10) values of J‐107088 against LX‐1‐ and PC‐3‐bearing mice were 578 and 1200 mg/m2. The ratio of LD10/GID75 indicates the therapeutic window of an anti‐tumor agent. Although the ratios of doxorubicin, paclitaxel and cisplatin against PC‐3 were <0.3, <0.5 and <0.2, J‐107showed the widest therapeutic window among the anti‐tumor drugs tested. J‐107088 was also effective on cells that had acquired resistance related to P‐glycoprotein. Furthermore, J‐107088 was found to be highly effective in inhibiting proliferation of micro‐metastases of tumors to the liver in mice. Therefore, J‐107088 is considered to be a promising candidate as an anti‐tumor drug for treatment of solid tumors in humans.
Risk Factors for Lung Cancer among Northern Thai Women: Epidemiological, Nutritional, Serological, and Bacteriological Surveys of Residents in High‐ and Low‐incidence Areas
Authors: Nakachi Kei , Limtrakul Porn‐ngarm , Sonklin Prapaisri , Sonklin On‐a‐nong , Jarern Chairat Tor , Lipigorngoson Suwiwek , Arai Kazuaki , Sone Yoshiaki , Imai Kazue , Suga Kenji , Matsuyama Satoru , Shimizu Hiroyuki , Takahashi Takashi , Suttajit Maitree
Published: August 2005

Lung cancer incidence among Northern Thai women is one of the highest in Asia (an annual age‐adjusted incidence rate of 37.4 per 100,000), and the incidence rate significantly differs by geographical districts. Therefore, we conducted a comparative study of women living in the Sarapee area, which showed the highest (crude incidence rate, 40.9), and the Chom Tong area, which had one of the lowest incidence rates (8.5) in Chiang Mai Province, despite the two areas' geographical and cultural closeness. The women in this study were either family members of lung cancer patients or their neighbors. To find clues to the etiology of lung cancer, this study used various epidemiological and biochemical approaches: interviewing on lifestyle factors, duplicate meals, chemical examination of drinking water, biochemical analysis of sera, mutagenicity test of urine, and monitoring of fungi and bacteria in the living environment. We found that tobacco smoking (Khiyo, local cigars) was less frequently observed in Sarapee (high incidence), compared with Chom Tong (low incidence), and that the history of chronic benign respiratory diseases was the most distinct event among women in Sarapee, resulting in a significantly increased percentage of those with a history of both benign respiratory diseases and tobacco smoking. This population revealed increased levels of serum tumor necrosis factor (TNF)‐α, an endogenous tumor promoter. Furthermore, significantly increased urine mutagenicity was found to be closely associated with history of benign respiratory disease in Sarapee. The fungus which was most commonly found in the air inside houses in Sarapee was identified as Microsporum canis. Additionally, significantly increased serum concentrations of a constituent of the fungus were found in Sarapee women, compared with those in Chom Tong. Our results suggest that tobacco (Khiyo) smoking alone may not be able to explain the very high incidence of female lung cancer in Northern Thailand, and that chronic benign respiratory disease, possibly caused by the infection of fungi such as M. canis, is likely to be involved in the etiology of female lung cancer in North Thailand.
Increased Choline Kinase Activity in 1,2‐Dimethylhydrazine‐induced Rat Colon Cancer
Authors: Nakagami Katsunao , Uchida Tsutomu , Ohwada Susumu , Koibuchi Yukio , Morishita Yasuo
Published: August 2005

Cancer cells acquire particular characteristics that benefit their proliferation. We previously reported that human colon cancers examined had increased choline kinase activity and phospho‐choline levels. The elevated phosphocholine levels were in part due to both activation of choline kinase and increased choline kinase α protein levels. In this report, we analyzed choline kinase, which catalyzes the phosphorylation of choline to produce phosphocholine, in rat 1,2‐dimethylhy‐drazine (DMH)‐induced colon cancer. This study is the first to demonstrate increased choline kinase α enzymatic activity, protein levels, and mRNA levels in DMH‐induced colon cancer as well as human colon cancer, although phosphocholine was not increased in DMH‐induced rat cancer. The increase in the mRNA level was partly due to an increase in the transcription of the choline kinase α gene. The increased choline kinase activity may be a specific characteristic acquired by cancer cells that benefits their proliferation.
An Antioxidant, Probucol, Induces Anti‐angiogenesis and Apoptosis in Athymic Nude Mouse Xenografted Human Head and Neck Squamous Carcinoma Cells
Authors: Nishimura Goshi , Yanoma Syunsuke , Mizuno Hiromi , Kawakami Koji , Tsukuda Mamoru
Published: August 2005

Probucol is a very strong synthetic antioxidant that was been safely used for the treatment of hyperlipidemia in Japan since 1985. It has been reported that lipid oxidation products can alter growth factor production, which could influence smooth muscle cell proliferation. Oxidized low density lipoprotein can influence smooth muscle cell proliferation by enhancing the expression of platelet‐derived growth factor (PDGF)‐AA gene and PDGF receptor in vascular smooth muscle cell. Further, free radical reactions can cause irreversible alterations of genomic constituents during the initiation phase of carcinogenesis. Antioxidant is considered to protect lipids and low density lipoprotein (LDL) from oxidation, which potentially inhibits angiogenesis, and rapid removal of free radicals by antioxidants could have an anti‐carcinogenic effect. In the present study, we investigated whether antioxidant treatment with probucol had an antitumor effect on KB cells, a human head and neck squamous carcinoma cell line. Probucol did not have any effect on KB cells in vitro, but probucol treatment of KB cells xenografts in mice had a significant antitumor effect through anti‐angiogenic and apoptosis‐inducing actions. These results support the idea that probucol is useful for preventing and/or treating cancer.
Reduced T Cell Response in Carcinogen‐sensitive Donryu Rats Compared with Carcinogen‐resistant DRH Rats
Authors: Mise‐Omata Setsuko , Sugiura Tsutomu , Higashi Ken , Yamashita Uki
Published: August 2005

Carcinogen‐resistant DRH rats were developed from carcinogen‐sensitive Donryu rats, which showed a high incidence of hepatic tumors when they were exposed to 3?‐methyl‐4‐dimethyl‐aminoazobenzene (3′‐MeDAB4) or other aminoazo hepatocarcinogens. In order to study the mechanism of the difference of carcinogenesis, we studied the immunological competence of Donryu rats compared with that of DRH rats. Anti‐keyhole limpet hemocyanin (KLH) antibody and KLH‐specific delayed hypersensitivity (DTH) responses after immunization with KLH were reduced in Donryu rats compared with DRH rats. Proliferative responses of spleen cells to KLH and nonspecific mitogens such as conconavalin A (Con A) and phytohemagglutinin (PHA) were significantly lower in Donryu rats than in DRH rats. Upon the cross‐linking of T cell receptor (TCR) complex using anti‐CD3 monoclonal antibody (Mab), spleen cells from Donryu rats proliferated poorly. Two other strains of rats, SD and Wistar, exhibited high responsiveness, comparable to that of DRH rats, indicating that the responsiveness of Donryu rats was impaired. The production of interleukin‐2 (IL‐2) upon stimulation with Con A and the responsiveness of Con A blasts to exogenous IL‐2 were also attenuated in Donryu rats. In contrast to T cell responsiveness, natural killer (NK) cell activity of spleen was increased in Donryu rats. Flow cytometric analysis revealed that the expression of CD4 and CD8 on T cells was decreased in Donryu rats, though the expression of other T cell markers such as CD2, CD3 and CD5 was not different. These results indicate that Donryu rats, which have been used in many years for cancer research in Japan, have impaired immunological surveillance mechanisms. This is likely to be one of the factors accounting for the high sensitivity to chemical carcinogens and the high susceptibity to transplanted tumor cells of Donryu rats.
β‐Catenin Accumulation and Mutation of Exon 3 of the β‐Catenin Gene in Hepatocellular Carcinoma
Authors: Kondo Yutaka , Kanai Yae , Sakamoto Michiie , Genda Takuya , Mizokami Masashi , Ueda Ryuzo , Hirohashi Setsuo
Published: August 2005

study was conducted to clarify the contribution of β‐catenin accumulation and mutation of the β‐catenin gene to hepatocarcinogenesis. β‐Catenin accumulation was examined immunohistochemically in 38 paired samples of hepatocellular carcinoma (HCC) and corresponding non‐cancerous liver tissue. Gene mutation was analyzed by polymerase chain reaction‐single strand conformation polymorphism (PCR‐SSCP) and direct sequencing using intronic primers encompassing exon 3. Neither accumulation nor mutation was detected in non‐cancerous liver tissues that showed no remarkable histological features, chronic hepatitis or liver cirrhosis. Accumulation of β‐catenin was seen in the nucleus, cytoplasm or cell membrane in 15 of 38 (39%) HCC samples, and gene mutation was seen in 9 of 38 (24%) HCC samples. Although there was a significant correlation between accumulation and mutation (P<0.01), six HCCs without mutation also showed accumulation. Samples of early HCC showed neither accumulation nor mutation, and accumulation and mutation were each correlated significantly with portal vein tumor involvement (P<0.05). The present results indicate that (1) mutation of exon 3 of the β‐catenin gene can lead to β‐catenin accumulation, although other mechanisms of accumulation may also operate in HCC, and (2) β‐catenin accumulation and mutation of the β‐catenin gene are not early events in hepatocarcinogenesis, and may be associated with the malignant progression of HCC.
Frameshift Mutations and a Length Polymorphism in the hMSH3 Gene and the Spectrum of Microsatellite Instability in Sporadic Colon Cancer
Authors: Orimo Hideo , Nakajima Eiitsu , Ikejima Miyoko , Emi Mitsuru , Shimada Takashi
Published: August 2005

Mutations in the hMSH3 gene in sporadic colon cancer with microsatellite instability (MSI) were investigated, since several mismatch repair genes were known to be mutated in cancers with MSI, but only deletions in the (A)8 region in the hMSH3 gene have been reported. We also analyzed the relationships between hMSH3 mutations and the spectrum of MSI. We screened MSI in 79 sporadic colon cancer samples using mono‐ and dinucleotide repeat markers and the samples with MSI were further analyzed for tri‐ and tetranucleotide repeat instability and mutations in the hMSH3 gene by polymerase chain reaction‐single strand conformation polymorphism (PCR‐SSCP) analysis. Five (6%) out of 79 tumors were MSI‐H and 15 (19%) were MSI‐L. Two MSI‐H tumors showed insertion in the (C)8 region in the hMSH6 gene and one tumor showed insertion and deletion in the (A)8 region in the hMSH3 gene, and two of the three above tumors showed MSI in tri‐and tetranucleotide repeats. One MSI‐L tumor showed somatic alteration in a 9‐bp repeat sequence in hMSH3. No frameshift mutations were found in the (A)7 and (A)6 regions in hMSH3. Thus, we confirmed that the (A)8 region in hMSH3 is a hot spot and mutations in the (A)7 and (A)6 regions in hMSH3 are not common. The hMSH3 mutation may enhance genomic instability in some colorectal cancers.
Frequent Allelic Imbalance on Chromosome 18q21 in Early Superficial Colorectal Cancers
Authors: Akiyama Yoshimitsu , Arai Takehiro , Nagasaki Hiromi , Yagi Osmar Kenji , Nakahata Atsuko , Nakajima Tomoko , Ohkura Yasuo , Iwai Takehisa , Saitoh Kiyoshi , Yuasa Yasuhito
Published: August 2005

Genetic alterations in early superficial colorectal cancers have rarely been reported. In the present study, we searched for alterations in the APC and p53 genes in 27 superficial (20 depressed and 7 elevated) and 21 protruding colorectal cancers with submucosal invasion by means of PCR‐single strand conformation polymorphism. Allelic imbalance (AI) on five loci, i.e., 1p34‐36, 8p21‐22, 14q32, 18q21 and 22q12‐13, was also analyzed. Since a high incidence of 18q21 AI was detected in the superficial depressed cases, we further screened for alterations in Smad2, Smad4 and DCC. APC alterations were observed in three superficial depressed, one superficial elevated, and 11 protruding colorectal cancers, indicating that the frequency of APC alterations in superficial depressed cases was significantly lower than that in the protruding ones. There was no significant association between p53 alterations and macroscopic types. AI on 18q21 (13/20, 65%) was much higher than those on the other four loci in the superficial depressed cases. Moreover, the frequency of 18q21 AI in the superficial depressed cases was significantly higher than that in the protruding ones. Smad4 alterations were only detected in 1 of the 13 superficial depressed and 3 of the 17 protruding cases, while Smad2 and DCC alterations were not detected in any case examined. These data suggest that the carcinogenetic pathways of protruding and superficial depressed colorectal cancers are different, and that alterations of tumor suppressor gene(s) located on 18q21 other than Smad2, Smad4 and DCC might be associated with most superficial depressed colorectal cancers.
γ‐Irradiation Deregulates Cell Cycle Control and Apoptosis in Nevoid Basal Cell Carcinoma Syndrome‐derived Cells
Authors: Fujii Katsunori , Miyashita Toshiyuki , Takanashi Jun‐ichi , Sugita Katsuo , Kohno Yoichi , Nishie Haruko , Yasumoto Shin‐ichiro , Furue Masutaka , Yamada Masao
Published: August 2005

The nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterized by nevi, palmar and plantar pits, falx calcification, vertebrate anomalies and basal cell carcinomas. It is well known in NBCCS that γ‐irradiation to the skin induces basal cell carcinomas or causes an enlargement of the tumor size, although the details of the mechanism remain unknown. We have established lymphoblastoid cell lines from three NBCCS patients, and we present here the first evidence of abnormal cell cycle and apoptosis regulations. A novel mutation (single nucleotide deletion) in the coding region of the human patched gene, PTCH, was identified in two sibling patients, but no apparent abnormalities were detected in the gene of the remaining patient. Nevertheless, the three established cell lines showed similar features in the following analyses. Flow cytometric analyses revealed that the NBCCS‐derived cells were accumulated in the G2M phase after γ‐irradiation, whereas normal cells showed cell cycle arrest both in the G0G1 and G2M phases. The fraction of apoptotic cells after γ‐irradiation was smaller in the NBCCS cells. The level of p27 expression markedly decreased after γ‐irradiation in the NBCCS cells, although the effects of the irradiation on the expression profiles for p53, p21 and Rb did not differ in normal and NBCCS cells. These findings may provide a clue to the molecular mechanisms of tumorigenesis in NBCCS.
Significance of Heterogeneous Nuclear Ribonucleoprotein B1 as a New Early Detection Marker for Oral Squamous Cell Carcinoma
Authors: Goto Yuri , Sueoka Eisaburo , Chiba Hiroshige , Fujiki Hirota
Published: August 2005

The development of an early tumor detection marker for oral cancer is an obvious need due to the high recurrence rate and poor survival rate. Based on our previous report that overexpression of heterogeneous nuclear ribonucleoprotein (hnRNP) B1 protein was found in 100% of squamous cell carcinomas of human lung, we applied the same immunohistochemical method, using anti‐hnRNP B1 antibody, to human oral squamous cell carcinoma (OSCC). Seven human tissue sections of OSCC showed strong staining with anti‐hnRNP B1 antibody, and hnRNP B1 protein of 37 kDa was identified in protein fractions isolated from six of the cancerous tissue sections, while it was not found in adjacent noncancerous tissue. Moreover, three non‐homogeneous (nodular) leukoplakia sections showed significant anti‐hnRNP B1 staining. The results suggest that this antibody detects precancerous lesions as well as advanced lesions (stages I to IV) of OSCC. We also present positive results of cytodiagnosis for two smear specimens. All of the above results indicate that hnRNP B1 is a new and useful marker for early detection of OSCC.
Interaction of Docetaxel (“Taxotere”) with Human P‐Glycoprotein
Authors: Shirakawa Katsuro , Takara Kohji , Tanigawara Yusuke , Aoyama Nobuo , Kasuga Masato , Komada Fusao , Sakaeda Toshiyuki , Okumura Katsuhiko
Published: August 2005

The interaction of docetaxel (“Taxotere”) with P‐glycoprotein (P‐gp) was examined using porcine kidney epithelial LLC‐PK1 and LLC‐GA5‐COL150 cells, overexpressing human P‐gp selectively on the apical plasma membrane by transfection of human MDR1cDNA into the LLC‐PK1 cells. The basal‐to‐apical transport of [14C]docetaxel in LLC‐GA5‐COL150 cells significantly exceeded that in LLC‐PK1 cells, but the apical‐to‐basal transport was decreased in LLC‐GA5‐COL150 cells. The intracellular accumulation after its basal or apical application to LLC‐GA5‐COL150 cells was 4‐ to 20‐fold lower than that of LLC‐PK1 cells. Multidrug resistance (MDR) modulators, i.e., cyclosporin A and SDZ PSC 833, inhibited the basal‐to‐apical transport and increased the apical‐to‐basal transport of [14C] docetaxel in LLC‐GA5‐COL150 cells, but verapamil affected only apical‐to‐basal transport. The intracellular accumulation after basal or apical application to LLC‐GA5‐COL150 cells was also increased by these three MDR modulators. These observations demonstrated that docetaxel is a substrate for human P‐gp, suggesting that docetaxel‐drug interactions occur via P‐gp. The inhibition of [14C]docetaxel transport by the MDR modulators, as well as daunorubicin and vinblastine, was also found in LLC‐PK1 cells, which endogenously express P‐gp at lower levels, and concentrations showing similar levels of inhibition were lower than those in the case of LLC‐GA5‐COL150 cells. These observations indicate that it is necessary to consider the Pharmacokinetic and pharmacodynamic interactions of docetaxel via P‐gp.
Prostate‐specific Membrane Antigen‐derived Primers in a Nested Reverse Transcription Polymerase Chain Reaction for Detecting Prostatic Cancer Cells
Authors: Saimoto Atsuya , Saito Shiro , Murai Masaru
Published: August 2005

The detection of prostate‐specific membrane antigen (PSM) mRNA in the peripheral blood of prostate cancer patients by a nested reverse transcriptase‐polymerase chain reaction (RT‐PCR) assay is a useful and sensitive method for the identification of small foci of metastatic lesions. In this study, a nested RT‐PCR assay was performed using the two different PSM‐derived oligonucleotide primer sets reported by Israeli et al. and Loric et al. (termed PSM primers‐1 and primers‐2, respectively, in this report), and the differences in the specificity and sensitivity of these primer sets for detecting prostate cancer cells in the blood are discussed. The PCR assay using PSM primers‐1 showed DNA bands for 4 of 7 cases of metastatic prostate cancer and amplified the untreated genomic DNA, while that using PSM primers‐2 showed 6 bands without the amplification of the genomic DNA. In conclusion, PSM primers‐2 is superior to PSM primers‐1 for the detection of PSM mRNA in the peripheral blood of prostate cancer patients.
Possible Chemopreventive Effects of Bovine Lactoferrin on Esophagus and Lung Carcinogenesis in the Rat
Authors: Ushida Yoshihiko , Sekine Kazunori , Kuhara Tetsuya , Takasuka Nobuo , Iigo Masaaki , Maeda Mitsuaki , Tsuda Hiroyuki
Published: August 2005

A milk component, bovine lactoferrin (bLF), previously shown by us to be a strong chemopreventive of colon carcinoma development, was examined for its influence on other organs using a rat multi‐organ carcinogenesis model. Male F344 rats, aged 6 weeks, were treated sequentially with diethylnitrosamine (DEN, i.p.), dihydroxy‐di‐N‐propylnitrosamine (DHPN, in drinking water) and N‐nitrosomethylbenzylamine (NMBA, s.c.) during the first 8 weeks (DDN treatment), and then bLF was administered in the basal diet, at a dose of 2, 0.2, 0.02 or 0.002%. Other groups were given DDN treatment or bLF alone as controls. All surviving animals were killed at week 41, and major organs were examined histopathologically for neoplastic lesions. In the esophagus, a tendency for reduction in development of papillomas was evident in the bLF‐treated animals, along with a significant suppression of relatively large‐sized papillomas (more than 50 mm3 volume) at the 0.2% dose (P<0.05, 11% of the control). The multiplicity of tumors (adenomas and carcinomas) in the lung was also decreased in animals fed 0.02% bLF (1.98±0.41 per cm2 lung tissue section, P<0.05) compared to the control group (3.48±0.33). No enhancing or inhibitory effects of bLF on tumor development in other organs were noted. The present results indicate that bLF exerts chemopreventive effects in the esophagus and lung in addition to the colon.
High‐molecular‐weight Fibronectin Synthesized by Adenoid Cystic Carcinoma Cells of Salivary Gland Origin
Authors: Toyoshima Koh‐éi , Kimura Shinn , Cheng Jun , Oda Yohei , Mori Kazuhiro J. , Saku Takashi
Published: August 2005

To understand the morphogenesis of characteristic cribriform structures and the frequent invasion of salivary adenoid cystic carcinomas (ACC) along such basement membrane‐rich structures as peripheral nerves, we have isolated fibronectin (FN) from the culture media of ACC3 cells established from a parotid ACC and characterized its glycosylation and alternative splicing status. FN isolated from ACC3 cells (ACC‐FN) showed a molecular mass of 315 kDa in SDS‐PAGE and was less heterogeneous and larger than plasma FN (pFN) or FNs from other cell sources. Differential enzymatic treatments of immunoprecipitated ACC‐FN with neuraminidase, peptide‐N‐glycosidase F and endo‐α‐N‐acetylgalactosaminidase revealed that ACC‐FN was composed of a polypeptide chain of 270 kDa, with 10 kDa each of N‐linked and O‐linked oligosaccharide chains. Reverse transcription polymerase chain reaction (RT‐PCR), in‐situ hybridization, and immunofluorescence studies showed that most ACC‐FNs contained ED‐A, ED‐B and IIICS regions in the molecules. This alternative splicing status of ACC‐FN seemed to contribute to its less heterogeneous and larger molecular form. Cell attachment assay demonstrated that ACC‐FN was more potent than pFN in adhesion of ACC3 cells. The results indicated that ACC‐FN may function as a substrate for attachment of ACC3 cells, or that ACC3 cells trap and retain ACC‐FN in their pericellular space. This isoform of FN may play an important role in the mode of invasion of ACC and the formation of stromal pseudocysts in the characteristic cribriform structure of ACC.
Posttreatment M‐Protein Nadir Level Is a Significant Prognostic Factor Associated with Survival in Multiple Myeloma
Authors: Shimizu Kazuyuki , Kamiya Osamu , Hirabayashi Noriyuki , Ichikawa Atsushi , Kawashima Kohei , Kobayashi Masahide , Mizuno Harumitsu , Nagura Eiichi , Nitta Masakazu , Saito Hidehiko , Sao Hiroshi , Shibata Toshihiko , Takeyama Hideo ,   Nagoya Myeloma Cooperative Study Group
Published: August 2005

In the present study 142 patients with myeloma (102 with IgG M‐protein and 40 with IgA) treated with either VMCP (65 patients) or MMCP (77 patients) as remission induction therapy were retrospectively analyzed. Response to treatment was evaluated in terms of a more‐than‐50% fall of pretreatment M‐protein and the posttreatment M‐protein nadir. Though significantly more patients treated with MMCP achieved partial response (PR) as compared with those treated with VMCP (P=0.019) and though patients achieving PR showed a significantly longer survival than those with less responsiveness (P=0.0091), the difference in survival curves between the two treatment groups was not significant (P=0.1871). The difference in response between the treatment groups evaluated in terms of posttreatment nadir was not significant (P=0.507). Multivariate analysis identified posttreatment M‐protein nadir as a significant prognostic factor associated with survival, along with 3 other factors: sex, performance status, and hemoglobin. The lack of difference between the survival curves for patients treated with the 2 regimens despite the significantly different response rates evaluated in terms of percent fall of pretreatment M‐protein levels was considered to be due to the lack of a difference in the ability to induce a deep posttreatment nadir between the regimens. Posttreatment M‐protein nadir is an important prognostic factor associated with survival and should be included in the evaluation of the efficacy of chemotherapy.
Role of Copper Accumulation in Spontaneous Renal Carcinogenesis in Long‐Evans Cinnamon Rats
Authors: Kitaura Keisuke , Chone Yoshifumi , Satake Nobuo , Akagi Akiko , Ohnishi Takamasa , Suzuki Yasuo , Izumi Keisuke
Published: August 2005

Spontaneous renal cell tumors in totals of 223 male and female Long‐Evans Cinnamon (LEC) rats of 51–120 weeks old, 157 male F344 rats of 51–120 weeks old, and 14 male Long‐Evans Agouti (LEA) rats of 51–70 weeks old were examined histologically. The incidences of renal cell tumors increased with age in male and female LEC rats, but no tumors developed in F344 or LEA rats. Dilated atypical tubules of the kidneys were observed at high incidence in aged LEC rats. Copper staining of LEC rat kidneys showed a positive reaction in proximal tubules of the cortex and the outer stripe of the medulla. The renal copper concentration of LEC rats reached a peak in the period of necrotizing hepatitis with renal tubular necrosis, and was higher than that in F344 rats for up to 106 weeks. In contrast, the renal iron concentration of LEC rats was lower than that in F344 rats except in the period of necrotizing hepatitis. Long‐term treatment of LEC rats with d‐penicillamine, a copper‐chelating agent, inhibited accumulation of copper, but not iron, in the kidneys, and inhibited the development of karyomegaly of proximal tubules and dilated atypical tubules. These results suggest that persistent copper accumulation after toxic necrosis of tubules is the major cause of spontaneous renal carcinogenesis in LEC rats.
Organ‐dependent Modifying Effects of Caffeine, and Two Naturally Occurring Antioxidants α‐Tocopherol and n‐Tritriacontane‐16,18‐dione, on 2‐Amino‐1‐methyl‐6‐phenylimidazo [4,5‐b] pyridine (PhIP)‐induced Mammary and Colonic Carcinogenesis in Female F344 Rats
Authors: Hagiwara Akihiro , Boonyaphiphat Plumjit , Tanaka Hikaru , Kawabe Mayumi , Tamano Seiko , Kaneko Hideo , Matsui Masayoshi , Hirose Masao , Ito Nobuyuki , Shirai Tomoyuki
Published: August 2005

Modifying effects of caffeine, α‐tocopherol, and n‐tritriacontane‐16,18‐dione (TTAD) on 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP)‐induced mammary and colonic carcinogenesis were investigated in female F344 rats. Groups of 20 rats, 6 weeks old, were given 0.02% PhIP (in diet) alone, or together with 0.1% caffeine (in drinking water), 0.5%α‐tocopherol (in diet) or 0.1% TTAD (in diet) for up to 54 weeks. Groups of 10 females receiving basal diet or one of the test chemicals without PhIP supplementation were also maintained. The final combined incidences (adenomas plus adenocarcinomas) and multiplicity (No./rat) of mammary adenomas and adenocarcinomas were significantly lowered in the PhIP plus caffeine group (10%, 0.10) as compared to the PhIP alone value (40%, 0.50). Incidences of mammary tumors in the PhIP plus α‐tocopherol or TTAD groups tended to be decreased while their multiplicities were significantly lowered. With regard to colon tumor development, on the other hand, rats given PhIP plus caffeine exhibited an elevated incidence (75% versus 15% in the control), whereas α‐tocopherol and TTAD had no effect. Surprisingly, metabolic activation of PhIP was inhibited by addition of caffeine in an in vitro assay. The results indicate that caffeine exerts a potent chemopreventive action against PhIP‐induced mammary carcinogenesis, but acts as a co‐carcinogen for PhIP‐induced colonic carcinogenesis.
Increased Choline Kinase Activity and Elevated Phosphocholine Levels in Human Colon Cancer†
Authors: Nakagami Katsunao , Uchida Tsutomu , Ohwada Susumu , Koibuchi Yukio , Suda Yasuo , Sekine Takeshi , Morishita Yasuo
Published: August 2005

Nuclear magnetic resonance spectroscopy has detected elevated phosphocholine levels in human tumor tissues and cells, and in cells that were transformed with the activated Ha‐ras gene and stimulated in vitro with growth‐promoting factors such as platelet‐derived growth factor, epidermal growth factor, and phorbol ester. However, the mechanism of the elevation and the function of the increased phosphocholine levels have not been clearly demonstrated. We studied phosphocholine levels enzymatically and analyzed the activity of choline kinase, which catalyzes the phosphorylation of choline to produce phosphocholine, in human colon cancer and adenoma. Both choline kinase activity and phosphocholine levels were increased in colon cancer and adenoma tissue. The activation of choline kinase and the increased levels of choline kinase α were partly responsible for the elevated phosphocholine levels. This study suggests that choline kinase might play a role in growth promotion or signal transduction in carcinogenesis.
p53 Status Predicts the Efficacy of Postoperative Oral Administration of Tegafur for Completely Resected Non‐small Cell Lung Cancer†
Authors: Tanaka Fumihiro , Yanagihara Kazuhiro , Ohtake Yohsuke , Miyahara Ryou , Kawano Youzou , Fukuse Tatsuo , Hitomi Shigeki , Wada Hiromi
Published: August 2005

Although postoperative adjuvant therapy for non‐small cell lung cancer (NSCLC) had not been reported to be effective, it has been reported recently that oral administration of tegafur (1‐[2‐tetrahydrofuryl]‐5‐fluorouracil, FT) may improve the postoperative prognosis. In the present paper, to examine whether p53 status affects the efficacy of FT as postoperative adjuvant chemotherapy for NSCLC, a total of 236 consecutive patients with completely resected pathologic stage I–IIIa NSCLC were retrospectively reviewed. p53 status was determined by immunohistochemical staining. For all patients, the 5‐year survival rate of patients with FT administration (FT group) was 78.1%, being significantly higher than that (69.1%) of patients without FT administration (control group) (P=0.046). For patients without immunohistochemical evidence of p53 overexpression, the 5‐year survival rate in the FT group was 87.1%, being significantly higher than that (74.0%) in the control group (P=0.036). This demonstrates an improvement of postoperative prognosis by FT administration. On the other hand, for patients with p53 overexpression, there was no significant difference in the postoperative prognosis between the FT group and the control group (5‐year survival rate 63.2% and 60.1%, respectively; P=0.514), demonstrating that FT administration was not effective for these patients. In conclusion, p53 status may be useful for predicting the efficacy of postoperative adjuvant chemotherapy using FT. A prospective randomized study stratified by p53 status is needed to clarify the effect of postoperative FT administration.
Significance of Membrane Type 1 Matrix Metalloproteinase Expression in Breast Cancer
Authors: Ishigaki Shinsuke , Toi Masakazu , Ueno Takayuki , Matsumoto Hiroshi , Muta Mariko , Koike Morio , Seiki Motoharu
Published: August 2005

Expression of matrix metalloproteinases (MMPs) plays an essential role in tumor metastasis and invasion through the degradation of extracellular matrix (ECM). MT1‐MMP (membrane type 1 matrix metalloproteinase), a membrane‐type MMP, is responsible for the activation of MMP2. In this study the significance of MT1‐MMP expression in human breast tumors was investigated by immunocytochemical assay, and its correlation with clinicobiological features was analyzed. MT1‐MMP expression was detected in tumor cells and/or stromal cells, and there was a strong correlation between the expressions of MT1‐MMP in the two cell types. Out of 183 primary tumors, 103 (56.2%) showed positive staining of MT1‐MMP in tumor cells. MT1‐MMP expression showed no significant correlation with any of the clinicobiological parameters examined, including hormone receptor status and angiogenesis. In postoperative survival analysis, MT1‐MMP expression itself was not a significant prognostic factor. However, in the particular subgroup with the accumulation of thymidine phosphorylase (TP)‐positive stromal cells, which have been activated by various stimuli, such as cytokines and hypoxia, MT1‐MMP expression had a significant prognostic value. These data suggested that MT1‐MMP might function cooperatively with tumor‐associated stromal cells for the progression of breast cancer.
Differentiation of a Cell Line of Human Cervical Argyrophil Small Cell Carcinoma to Macrophage Lineage Cells
Authors: Ichimura Hiroshi , Sakashita Nobuhiro , Iida Tohko , Chisaka Takeshi , Yasuda Hiroaki , Kita Masakazu , Yuasa Souichi , Imanishi Jiro
Published: August 2005

To investigate the origin of argyrophil small cell carcinoma (ASCC) of the uterine cervix, we examined the influence of dibutyryl cyclic adenosine 3′,5′‐monophosphate (dB‐cAMP), a known differentiation inducer, on the characteristics of an ASCC cell line, TC‐YIK, which has been shown to be a useful in vitro experimental model of ASCC. In TC‐YIK cells after treatment with dB‐cAMP, two specific antigenic markers of macrophages, CD14 and human leukocyte antigen‐DR, were detected by flow cytometric analysis. In addition, interferon‐γ mRNA was detected by reverse transcription‐polymerase chain reaction and interferon‐γ protein was detected by ELISA. More than 90% of the cells stained positive for α‐naphthyl butyrate esterase, 1% of the cells showed phagocytotic activity against Micrococcus lysodeikticus, and 22% of the cells had M. lysodeikticus adsorbed on their surface. Furthermore, granulocyte‐macrophage colony stimulating factor accelerated the proliferation of TC‐YIK cells. These results indicate that dB‐cAMP promotes differentiation of ASCC cells to macrophages. In contrast, less than 10% of the cells showed stellate morphology, suggesting differentiation to neuronal cells after treatment with dB‐cAMP, as reported previously. Thus, TC‐YIK cells have been shown to differentiate both into macrophage lineage cells and neuronal cells, suggesting that ASCC originates from undifferentiated stem cells.
Immunohistochemical Detection of Human Telomerase Reverse Transcriptase in Normal Mucosa and Precancerous Lesions of the Stomach
Authors: Yasui Wataru , Tahara Eiji , Tahara Hidetoshi , Fujimoto Junya , Naka Kazuhito , Nakayama Junichi , Ishikawa Fuyuki , Ide Toshinori , Tahara Eiichi
Published: August 2005

Telomerase activity confers cell immortality through stabilization of the chromosome, participating in the development of a majority of human cancers. Human telomerase reverse transcriptase (TERT) has been identified as a catalytic subunit of telomerase, and is overexpressed in most gastric carcinomas. We immunohistochemically examined the expression of TERT in normal gastric mucosa and candidate precancerous lesions such as intestinal metaplasia and adenoma. In non‐neoplastic gastric mucosa including intestinal metaplasia and normal fundic mucosa, weak but significant expression of TERT was detected in nuclei of epithelial cells located in the lower two‐thirds of the glands (wider than the proliferative zone). The telomerase activity was found in a half of gastric adenomas, whose levels of the activity were about 10% of those in gastric carcinomas. TERT protein was expressed in the nuclei of the adenoma cells at moderate levels, that were not necessarily comparable with the telomerase activities. These findings overall suggest that TERT expression may be one of the prerequisites for telomerase activation in an early stage of stomach carcinogenesis.
Human p53‐p51 (p53‐Related) Fusion Protein: A Potent BAX Transactivator
Authors: Ikawa Shuntaro , Obinata Masuo , Ikawa Yoji
Published: August 2005

We recently discovered human p51, a new gene structurally and functionally related to human p53. This gene encodes two major splicing variants, p51A and p51B, which differ in their carboxyl‐terminal structure. However, p51A shows strong transactivation potential, while p51B has only weak potential. To clarify the reason for this difference, we made chimeric gene constructs expressing fusion proteins of p53‐p51A and p53‐p51B, having an N‐terminus of p53 and a C‐terminus of p51A or p51B, respectively. In a BAX promoter‐luciferase assay using p53‐deficient SAOS‐2 cells, they exhibited up to 30‐fold stronger transactivation potential than p53 and p51A themselves, suggesting that the C‐terminus of p51B does not simply serve as a repressor. We obtained similar results with p21WAF1 promoter‐reporter plasmids. These chimeras will be valuable tools for gene therapy.