bluuebunny/crossref_metadata_2025 huggingface dataset:
Restoration of the Cellular Senescence Program and Repression of Telomerase by Human Chromosome 3
Authors: Ohmura Hiroshi , Tahara Hidetoshi , Suzuki Mikio , Ide Toshinori , Shimizu Motoyuki , Yoshida Mitsuaki A. , Tahara Eiichi , Shay Jerry W. , Barrett J. Carl , Oshimura Mitsuo
Published: August 2005

Telomeres, at the end of chromosomes, shorten with each cell division, resulting in cellular senescence. Tumor cells, unlike normal somatic cells, express a telomerase that maintains the telomere length. Deletion of a gene(s) on chromosome 3 is common in human renal cell carcinoma (RCC) and reintroduction of a normal chromosome 3 into an RCC immortal cell line restored the program of cellular senescence. The loss of indefinite growth potential was associated with the loss of telomerase activity and shortening of telomeres in the RCC cells with a normal chromosome 3. However, microcell hybrids that escaped from senescence and microcell hybrids with an introduced chromosome 7 or 11 maintained telomere lengths and telomerase activity similar to those of the parental RCC23. Thus, restoration of the cellular senescence program by chromosome 3 is associated with repression of telomerase function in RCC cells.
Progesterone Enhancement of Stomach Tumor Development in SD Rats Treated with N‐Methyl‐N'‐nitro‐N‐nitrosoguanidine
Authors: Ando Yasumi , Watanabe Hiromitsu , Fujimoto Nariaki , Ito Akihiro , Toge Tetsuya
Published: August 2005

The effects of chronic progesterone treatment on gastric tumorigenesis were examined in 6‐week‐old male SD rats. The rats were castrated, progesterone or testosterone pellets were implanted, and, starting one week after the operation, 100 mg/liter of N‐methyl‐N‐nitro‐N'‐nitrosoguanidine (MNNG) was administered in the drinking water for 16 weeks. Every 2 months the pellets were changed. Group 1 animals received castration plus MNNG while Groups 2 and 3 also received progesterone and testosterone, respectively. In the Group 4 case, progesterone and testosterone were administered alternately for 2‐month periods and in Group 5 MNNG was given to intact animals. All survivors were killed one year after the start of MNNG treatment. In Group 1 the incidence of gastric tumors was significantly decreased as compared with the Group 5 value. The Group 2 incidence, in contrast, was similar to that in Group 5, and the size of the observed gastric tumors was massively increased. The area of the pyloric gland mucosa was also greater than in other groups. Testosterone treatment was associated with a less pronounced increase in tumor size and a recovery in incidence. The results indicate that progesterone may exert a promoting influence on gastric tumor development.
Expression of Integrin α3 in Gastric and Colorectal Cancers: Its Relation to Wall Contraction and Mode of Invasion
Authors: Boku Narikazu , Yoshida Shigeaki , Ohtsu Atsushi , Fujii Takahiro , Koba Ikuro , Oda Yasushi , Ryu Munemasa , Matsumoto Takeo , Hasebe Takahiro , Hosokawa Koichi , Yamao Takekazu , Saito Daizo , Moriya Nobuhiro , Abe Kaoru
Published: August 2005

We macroscopically classified 25 gastric and 23 colorectal advanced cancers into “contracted” and “uncontracted” types, and found immunohistochemically that integrin subunit α3 was more frequently expressed in the extracellular matrix (ECM) in the former than in the latter (75%:9/12 vs. 38%: 5/13 in gastric and 86%:6/7 vs. 25%:4/16 in colorectal cancers, respectively). Integrin subunit α3 was also expressed more frequently in cancers producing transforming growth factor‐beta (TGF‐β), which is related to ECM deposition, integrin expression and cell mobility, than in those which did not produce TGF‐β (67%:10/15 vs. 40%:4/10 in gastric and 57%:4/7 vs. 38%:6/16 in colorectal cancers, respectively). In addition, integrin subunit α3 was not expressed in 2 benign gastric ulcers combined with gastric cancer elsewhere in the stomach. On the other hand, a retrospective analysis of 107 cases of rectal cancer which recurred after a curative operation revealed that local recurrence was more frequent in “contracted” than “uncontracted” types (44%:ll/25 vs. 26%:21/82). These results may suggest that the abundant interstitial fibrosis which leads to remarkable gastric or colorectal wall contraction is a result of the interaction between cancer cells and ECM, along with the expression of integrin and/or the production of TGF‐β, This fibrosis may also be closely related to the mode of gastric and colorectal cancer invasion.
Induction of Erythroid Differentiation by 5‐Fluorouracil in K562 Leukemia Cells
Authors: Yang Ya‐Wun , Chang and Yea‐Hueay
Published: August 2005

K562 cell line, established from a patient in the blast crisis of chronic myeloid leukemia, expresses high levels of c‐myc and bcr/abl gene products. Exposure of K562 cells to 5‐fluorouracil (5‐FU) resulted in a marked benzidine‐positive erythroid differentiation with concomitant reduction in cell proliferation. No change in c‐myc mRNA or protein levels occurred during 96 h of drug treatment. In contrast, a biphasic change of p210bcr/abl and the abl‐associated kinase activities was observed upon treatment with 5‐FU. The change in p210bcr/abl expression may be mediated at the translational level, since the steady‐state level and the enzymatic activity of p210bcr/abl are reduced, whereas bcr/abl mRNA levels are unaltered. The results are consistent with the existence of pleiotropic differentiation pathways in K562 cells.
Analysis of Naturally Processed Human Histocompatibility Leukocyte Antigen Class I‐Bound Peptides from Hepatocellular Carcinoma Tissues in vivo
Authors: Kobayashi Hiroya , Sato Keisuke , Miyokawa Naoyuki , Kimura Shoji , Nakashima Manabu , Katagiri Makoto
Published: August 2005

Naturally processed self‐peptides bound to human histocompatibility leukocyte antigens (HLA) class I molecules of human hepatocellular carcinoma tissues (HLA‐A2.1, ‐B44, ‐B13) in vivo were isolated for sequence analysis. Acid‐eluted peptides were subjected to reversed‐phase high‐performance liquid chromatographic separation and single‐fraction sequencing was performed by Edman degradation. The peptides were found to be octamers or nonamers and they were derived from the processing of intracellular proteins. Three independent sequences were obtained from HLA‐A2.1 molecules. One of the peptides showed sequence homology to the hepatitis B virus (HBV) pre‐S protein, one to aldehyde dehydrogenase, and the other to no known protein. Two independent sequences were obtained from HLA‐B44, B13 molecules: one showed sequence homology to the human c‐abl protein, the other showed no homology to any known protein. A synthetic biotinylated peptide based on the HBV pre‐S peptide sequence was confirmed to bind to HLA‐A2.1 gene‐transfected L cells. These data suggested that peptides potentially recognized by cytotoxic T cells can bind to HLA class I molecules on tumor cells in vivo.
Tea Consumption and Lung Cancer Risk: A Case‐Control Study in Okinawa, Japan
Authors: Ohno Yoshiyuki , Wakai Kenji , Genka Keiichiro , Ohmine Keisho , Kawamura Takashi , Tamakoshi Akiko , Aoki Rie , Senda Masayo , Hayashi Yutaka , Nagao Keiichi , Fukutna Seigo , Aoki Kunio
Published: August 2005

To disclose the relationship between tea consumption and lung cancer risk, we analyzed the data from a case‐control study conducted in Okinawa, Japan from 1988 to 1991. The analysis, based on 333 cases and 666 age‐, sex‐ and residence‐matched controls, provided the following major findings, (a) The greater the intake of Okinawan tea (a partially fermented tea), the smaller the risk, particularly in women. For females, the odds ratios (and 95% confidence intervals) for those who consumed 1‐4, 5‐9, and 10 cups or more of Okinawan tea every day, relative to non‐daily tea drinkers, were 0.77 (0.28‐2.13), 0.77 (0.26‐2.25) and 0.38 (0.12‐1.18), respectively (trend: P=0.032). The corresponding odds ratios for males were 0.85 (0.46‐1.55), 0.85 (0.46‐1.56) and 0.57 (0.31‐1.06) (trend: P=0.053). (b) The risk reduction by Okinawan tea consumption was detected mainly in squamous cell carcinoma. Daily tea consumption significantly decreased the risk of squamous cell carcinoma in males and females, the odds ratios being 0.50 (95% confidence interval 0.27‐0.93) and 0.08 (0.01‐0.68), respectively. These findings suggest a protective effect of tea consumption against lung cancer in humans.
High Positive Rate of pS2 Expression in Forefront Intraductal Cancerous Area in Breast Cancer
Authors: Yamakawa Takashi , Morimoto Tadaoki , Sasa Mitsunori , Numoto Satoshi , Monden Yasumasa
Published: August 2005

Multiple sections of 40 consecutive cases with invasive ductal carcinoma of the breast, all of which had wide intraductal cancerous extension, were examined by immunohistochemicsl analysis for evaluation of hormone dependency in several areas of breast cancer tissues. In this study, we examined the expression of pS2 protein in the central invasive area (CIV), central intraductal cancerous area (CDC) and forefront intraductal cancerous area (FDC). pS2 staining was positive in 52.5% (21/40) of CIV and a significant correlation was found between pS2 expression in CIV and the estrogen receptor status (ER). pS2 staining was positive in 77.5% of CDC and 85.0% of FDC, respectively. A majority (68.4%) of the cases that were negative pS2 in CIV were positive for pS2 in FDC. Moreover, the cases with noncomedo intraductal carcinoma in premenopausal status showed a higher positivity of pS2 expression in FDC than the cases with comedo‐carcinoma, though the number of cases of comedo‐carcinoma was limited. These findings suggest that endocrine therapy may be useful after breast conserving treatment regardless of the ER status of the primary tumor.
Association of p53 Gene Mutations with Short Survival in Pancreatic Adenocarcinoma
Authors: Nakamori Shoji , Yashima Kazuo , Murakami Yoshinori , Ishikawa Osamu , Ohigashi Hiroaki , Imaoka Shingi , Yaegashi Sadanori , Konishi Yoichi , Sekiya Takao
Published: August 2005

Mutations of the p53 gene have been found in a variety of human cancers and are implicated in the biologic functions of cancer. To investigate the clinical implications of p53 mutations in pancreatic adenocarcinoma, we examined the association of mutations of the p53 gene with patients’ prognosis. Single‐strand conformational polymorphism analysis and direct DNA sequencing were used to detect p53 gene mutations in 37 pancreatic adenocarcinomas. p53 gene mutations were detected in 16 (43%) of the 37 pancreatic adenocarcinomas. Direct sequencing did not reveal preferential clustering at any specific codon. There was no significant association of the presence of p53 gene mutations with histologic types, extent of tumor invasion, the presence of lymph node metastasis, or tumor stage. Univariate analysis showed that survival of patients with p53‐gene‐mutation tumors was significantly poorer than that of patients with p53‐gene‐nonmutated tumors (p=0.02). Cox's multivariate analysis of ten clinicopathologic features including p53 gene mutations revealed that presence of p53 gene mutations (p= 0.026) and curativity of operation (p=0.014) were independent predictors of survival. Furthermore, the survival of patients with p53‐gene‐mutated tumor was significantly poorer than that of patients with p53‐gene‐nonmutated tumors, both in patients who underwent curative operation (p=0.04) and in patients who underwent non‐curative operation (p=0.01). These results suggested that mutations of the p53 gene might play an important role in cancer aggressiveness and could be a clinically useful predictor of prognosis in patients with pancreatic adenocarcinoma.
Isolation of a cDNA for a Growth Factor of Vascular Endothelial Cells from Human Lung Cancer Cells: Its Identity with Insulin‐like Growth Factor II
Authors: Hagiwara Koichi , Kobayashi Tatsuo , Tobita Masato , Kikyo Nobuaki , Yazaki Yoshio , Okabe Tetsuro
Published: August 2005

We have found growth‐promoting activity for vascular endothelial cells in the conditioned medium of a human lung cancer cell line, T3M‐11. Purification and characterization of the growth‐promoting activity have been carried out using ammonium sulfate precipitation and gel‐exclusion chromatography. The activity migrated as a single peak just after ribonuclease. It did not bind to a heparin affinity column. These results suggest that the activity is not a heparin‐binding growth factor (including fibroblast growth factors) or a vascular endothelial growth factor. To identify the molecule exhibiting the growth‐promoting activity, a cDNA encoding the growth factor was isolated through functional expression cloning in COS‐1 cells from a cDNA library prepared from T3M‐11 cells. The nucleotide sequence encoded by the cDNA proved to be identical with that of insulin‐like growth factor II.
Formation of 2‐Amino‐3‐methylimidazo[4,5‐f]quinoline‐ and 2‐Amino‐3,8‐dimethylimidazo[4,5‐f]quinoxaline‐sulfamates by cDNA‐expressed Mammalian Phenol Sulfotransferases
Authors: Ozawa Shogo , Nagata Kiyoshi , Yamazoe Yasushi , Kato Ryuichi
Published: August 2005

In rat liver cytosol systems, 2‐amino‐3‐methylimidazo[4,5‐f]quinoIine (IQ) and 2‐amino‐3,8‐dimethyl‐imidazo[4,5‐f]quinoxaline (MelQx) were converted into their sulfamates in the presence of 3′‐phosphoadenosine 5′‐phosphosulfate at rates of 51.2 and 50.7 pmol/min/mg cytosol in the male, and 23.7 and 22.5 pmol/min/mg cytosol in the female, respectively. IQ‐sulfamate formation was low (0.24 pmol/min/mg cytosol) in human liver cytosols, and MeIQx‐sulfamate was not detected (<0.1 pmol/ min/mg cytosol). These results suggest only a minor contribution of IQ‐ and MeIQx‐sulfamate formation to the detoxification of both heterocyclic amines in humans. Using sulfotransferase cDNA‐expression systems, a rat ST1A1 arylsulfotransferase has been shown to catalyze the formation of the sulfamates, suggesting a role of the ST1A type of sulfotransferase in the N‐sulfation of heterocyclic amines.
Over‐expressed ZF5 Gene Product, a c‐myc‐binding Protein Related to GL1‐Kruppel Protein, Has a Growth‐suppressive Activity in Mouse Cell Lines
Authors: Numoto Michitaka , Yokoro Ken , Yanagihara Kazuyoshi , Kamiya Kenji , Niwa Ohtsura
Published: August 2005

ZF5 encodes a zinc finger protein, which contains five C2H2‐type zinc fingers showing homology with the zinc finger of the Kruppel family, and binds to two sites in the mouse c‐myc promoter. We report the effect of over‐expression of ZF5 on cell growth. ZnCl2 treatment suppressed the growth of a mouse fibroblast cell line (L cells) transfected with the wild‐type ZF5 gene driven by the metallothionein promoter. Cells transfected with the wild‐type ZF5 gene formed colonies two‐ to fivefold less efficiently than those transfected with the mutant ZF5 gene in P19, NIH3T3, 3T3‐L1 and L cells. Over‐expression of ZF5 did not cause c‐myc down‐regulation or arrest of the cell cycle, but increased the DNA content.
A Mouse Erythroleukemia Cell Line Possessing Friend Spleen Focus‐forming Virus gp55 Transgene and Temperature‐sensitive Mutant p53 Gene
Authors: Xu Xin , Yamamura Yasuko , Tsukada Teruyo , Yoshida Mitsuaki A. , Senda Hisato , Nagayoshi Mariko , Ikeuchi Tatsuro , Ikawa Yoji
Published: August 2005

Two different erythroleukemia cell lines have been established from the splenic lesions of transgenic mice possessing the Friend spleen focus‐forming virus (F‐SFFV) gp55 gene. One showed a neardiploid karyotype and a temperature‐sensitive (ts) p53 mutation, and the other, a hyper‐triploid karyotype with double p53 mutations found by single‐strand conformation polymorphism (SSCP) analysis. The cell lines both retained No.11 chromosomes on which p53 genes are localized. Another p53 allele in the cell line with the ts‐p53 mutation appeared intact in the SSCP analysis of the genomic exon 5. The cells with the ts‐mutant p53 gene showed no apparent change with temperature shift in their growth or dimethylsulfoxide‐induced differentiation, although the wild‐type p53 gene on the other allele was not expressing. This ts‐p53val‐135 gene made p53‐deficient fibroblasts anchorageindependent at 37°C but not at 32°C. This non‐virus‐producing, mouse erythroleukemia cell line will be useful for the study of mutated p53 function during the induction of erythrodifferentiation or apoptotic change.
Expression of CD44 Variant Exons 8–10 in Colorectal Cancer and Its Relationship to Metastasis
Authors: Takeuchi Kazuo , Yamaguchi Akio , Urano Takeshi , Goi Takanori , Nakagawara Gizo , Shiku Hiroshi
Published: August 2005

Splice variants of CD44 are overexpressed in human lung, breast, and colon carcinoma cell lines. This study was conducted to clarify the association between the expression of CD44 variant exons 8–10 and metastatic potential in human colorectal cancer. We found that the expression of a CD44 splice variant containing exons v8–10 was increased in all of 60 colorectal cancer specimens examined compared with matched normal colorectal mucosa, as determined by Northern blotting. Expression of CD44 variant exons 8–10 did not significantly correlate with histological type, depth of tumor invasion, lymphatic invasion, venous invasion, or lymph node metastasis. However, the level of CD44 variant exon 8–10 expression was significantly higher in carcinomas associated with liver metastasis than in those without liver metastasis. In addition, expression of CD44 variant exons 8–10 in the liver metastases was more intense than that in the primary colorectal cancers. These findings indicated that this domain of the CD44 glycoprotein encoded by exons v8–10 may play an important role in tumor hematogenous metastasis of human colorectal cancer.
Non‐invasive Characterization of Brain Tumor by in‐vivo Proton Magnetic Resonance Spectroscopy
Authors: Harada Masafumi , Tanouchi Miki , Nishitani Hiromu , Miyoshi Hirokazu , Bandou Kazuhiko , Kannuki Seiji
Published: August 2005

We studied the feasibility of characterizing brain tumor tissue by localized proton magnetic resonance spectroscopy (1H‐MRS), Twenty‐six newly diagnosed tumors were examined by in‐vivo, 1H‐MRS. The NAA (N‐acetylaspartate)/Cho (choline) ratio of Grade 2 astrocytoma was higher than that of Grade 4. The Cho/Cr (creatine and phosphocreatine) ratio of meningioma was considerably higher than that of glioma of all grades. We have experienced only two cases of ependymoma and the Cho/Cr ratios of both were lower than that of glioma. It seems likely that 1H‐MRS can be used to differentiate Grade 2 from Grade 4 in most cases of astrocytoma based on the NAA/Cho ratio, though a few cases will overlap. Meningioma can be distingulshed easily from glioma, and the results of our study suggest that ependymoma shows a characteristic pattern on 1H‐MRS, different from those of other brain tumors.
Gene Expressions of Protein Tyrosine Phosphatases in Regenerating Rat Liver and Rat Ascites Hepatoma Cells
Authors: Kitamura Takaya , Nakamura Koji , Mizuno Yusuke , Kikuchi Kunimi
Published: August 2005

mRNA levels for ten protein tyrosine phosphatases (PTPs), PTP‐S, PTPH1, PTP‐1, GLEPP1, LRP, PTP1D, PTPG1, PTPγ, PTPδ, and LAR, were determined during regeneration of rat liver, and mRNA levels for 5 PTPs, PTP‐S, PTP‐1, PTPγ, PTPδ, and LRP, were determined in three lines of rat ascites hepatoma cells. In regenerating rat liver, the expression patterns of PTP genes after partial hepatectomy could be classified into four groups. In group 1 (PTP‐S and PTPH1), the mRNA levels increased rapidly, reached a maximum 7 h after partial hepatectomy, remained at a plateau for 1–2 days and then decreased gradually. In group 2 (PTP‐1, GLEPP1, and LRP), the mRNA levels showed two peaks on days 1 and 5, and then decreased gradually. In group 3 (PTP1D and PTPG1), the mRNA levels increased rapidly, reached a maximum at 7 h, remained high for several days, and then did not decrease but rather increased after day 7. In group 4 (PTPγ, PTPδ, and LAR), the mRNA levels remained constant for the first 5 days and increased over the control levels after day 7. In rat ascites hepatomas, gene expression of non‐receptor‐like PTPs (PTP‐S and PTP‐1) showed various neoplastic alterations, whereas mRNAs of receptor‐like PTPs (PTPγ, PTPdL, and LRP) were lost or drastically decreased.
Cytotoxic Activity of CD4+ T Cells against Autologous Tumor Cells
Authors: Konomi Yasushi , Sekine Teruaki , Takayama Tadatoshi , Fuji Masashi , Tanaka Takashi
Published: August 2005

The 51Cr‐release assay is mostly applied to detecting the cytotoxic activity of CD8+ T cells, and little is known about the activity of CD4+ T cells. Therefore, the correlation between the cytotoxic activity of CD4+ or CD8+ T cells and the incubation period with autologous tumor cells was analyzed by two methods. The incubation periods were 4 and 20 h (4 h and 20 h assay) for the 51Cr‐release assay. Eight pairs of tumor cells and T cells were assayed. T cells were fractionated into CD4+ and CD8+ T cells by using magnetic beads and panning methods, and those cells were activated by culture with recombinant interleukin‐2 and immobilized anti‐CD3 monoclonal antibody. In 6 out of 8 cases, no cytotoxic activity of CD4+ T cells was detected by the 4 h assay, whereas cytotoxic activity was detected in all cases in the 20 h assay. The cytotoxic activities in 20 h assay of CD4+ T cells were increased 67‐fold in comparison with the activities in 4 h assay (range: 5–197). In the case of CD8+ T cells, cytotoxic activities were detected in 6 out of 8 cases in the 4 h assay. The lytic unit ratio of CD4+ and CD8+ T cells was calculated as 1.5 in the 20 h assay (range: 0.2‐>7.2) versus 0.4 in the 4 h assay (range: < 0.1–1.3). Cytotoxic activities in colorimetric assay using Crystal Violet with a 24 h incubation were similar to those in the 20 h 51Cr‐release assay in all eight cases. These results indicate that CD4+ T cells have cytotoxic activity as strong as that of CD8+ T cells towards autologous tumor cells.
A Quantitative in vivo Method of Analyzing Human Tumor‐induced Angiogenesis in Mice Using Agarose Microencapsulation and Hemoglobin Enzyme‐linked Immunosorbent Assay
Authors: Okada Naoki , Fushimi Mariko , Nagata Yuriko , Fukunaga Tomoko , Tsutsumi Yasuo , Nakagawa Shinsaku , Mayumi Tadanori
Published: August 2005

This study was conducted to develop a quantitative assay system for use in the in vivo evaluation in mice of angiogenesis induced by human tumor cells. The human epidermoid carcinoma cells, A431 cells, were cultured on microcarriers. Microcarrier‐attached A431 cells (A431‐MC) were micro‐encapsulated with agarose hydrogel to isolate them from the immune system of the C57BL/6 mice after subcutaneous dorsal midline implantation. The agarose hydrogel‐mjcroencapsulated A431 cells (Aga‐A431 cells; diameter=300 (μm) survived for at least 10 days in vitro, and the proliferation profile of the Aga‐A431 cells was indistinguishable from that of non‐microencapsulated A431 cells. The Aga‐A431 cells were subcutaneously injected into mice with an 18‐gauge needle. Ten days later, few vessels had formed at the site implanted with cell‐free agarose beads, whereas notable angiogenesis was observed at the site implanted with Aga‐A431 cells. The degree of angiogenesis was evaluated by measurement of the hemoglobin content in the implanted site using a mouse hemoglobin (mHb) enzyme‐linked immunosorbent assay (ELISA) system. This mHb‐ELISA system has the advantages of great simplicity and reproducibility. The measured mHb content of new blood vessels at the site implanted with agarose beads was in good agreement with the amount of angiogenesis observed under a stereoscopic microscope. This assay system enabled us to evaluate the angiogenesis induced by xenogeneic cells, such as human tumor cells. Thus, our novel method may be useful for the study of the angiogenic potential of various human tumor cells and in research on the anti‐angiogenic properties of various agents.
Prospective Evaluation of the Feasibility of Cisplatin‐based Chemotherapy for Elderly Lung Cancer Patients with Normal Organ Functions
Authors: Oshita Fumihiro , Kurata Takayasu , Kasai Takashi , Fukuda Minoru , Yamamoto Nobuyuki , Ohe Yuichiro , Tamura Tomohide , Eguchi Kenji , Shinkai Tetsu , Saijo Nagahiro
Published: August 2005

A study was conducted to examine the feasibility of cisplatin‐based chemotherapy in elderly patients (75 years old) with advanced non‐small cell lung cancer (NSCLC) or small cell lung cancer (SCLC). Thirty‐four patients were enrolled between September 1993 and December 1994. Patients with normal organ function and good performance status (PS) received cisplatin‐based chemotherapy (cisplatin 80 mg/m2 on day 1 and vindesine 3 mg/m2 on days 2 and 8 for NSCLC, or cisplatin 80 mg/ m2 on day 1 and etoposide 100 mg/m2 on days 2 to 4 for SCLC). Ten patients (29%) were eligible for this study, 7 with NSCLC and 3 with SCLC. Reasons for exclusion were ischemic heart disease in 14, poor PS (2) in 11, reduced creatinine clearance (Ccr) in 10, abnormal electrocardiogram without ischemia in 9 and noncompliance with the protocol in 2 patients. Eight patients had two or more reasons. Nine of the 10 eligible patients were able to tolerate 2 or more courses of chemotherapy. All 3 patients with SCLC responded (1 complete response and 2 partial response), but only 1 of the patients with NSCLC achieved partial response. Toxicity was evaluated according to Japan Clinical Oncology Group criteria. All but one patient experienced grade 4 neutropenia, and 6 patients had infectious episodes requiring antibiotics. Grade 3 anemia and thrombocytopenia were observed in 1 and 2 patients, respectively. Non‐hematological toxicities were mild. Only 10 of 34 patients (29%) satisfied our eligibility criteria and they experienced severe myelotoxicity. We conclude that chemotherapy should be given carefully to elderly patients even if they appear to have normal organ function.
Therapy and Imaging of Pancreatic Carcinoma Xenografts with Radioiodine‐labeled Chimeric Monoclonal Antibody A10 and Its Fab Fragment
Authors: Kamigaki Takashi , Yamamoto Masahiro , Ohyanagi Harumasa , Ohya Masato , Shimazoe Takao , Kono Akira , Ohtani Wataru , Narita Yuji , Ohkubo Masahiro , Saitoh Yoichi
Published: August 2005

Recombinant mouse/human chimeric monoclonal antibody A10 (ch‐A10) and its Fab fragment (ch‐Fab) react with carcinoembryonic antigen on various gastrointestinal carcinomas. We performed biodistribution studies with 125I‐labeled ch‐Al0 and ch‐Fab in an antigen‐positive human pancreatic carcinoma (BxPC‐3) xenograft model. We also evaluated the anti‐tumor effect of 131I‐labeled ch‐Al0 and studied the detection of BxPC‐3 xenografts with 123I‐labeIed ch‐Fab in whole body scintigraphy. In comparative biodistribution studies, the tumor uptake of 125I‐labeled ch‐Al0 was significantly greater than that of 125I‐labeIed ch‐Fab 24 h post‐injection. However, the tumor‐to‐blood ratio was 46.8 for ch‐Fab at 24 h post‐injection, while it was only 1.4 for ch‐Al0. Microautoradiography studies showed that ch‐Fab penetrated more uniformly into the tumor nodules than did ch‐Al0. In mice given a therapeutic dose of 131I‐labeled ch‐AlO, a significant inhibition of tumor growth was seen, while control I31l‐labeled human IgG did not affect tumor growth. Leukocyte toxicity was observed within 3 weeks after injection of 131I‐labeled ch‐Al0, but leukocyte counts recovered to normal levels at 8 weeks post‐injection. In whole‐body scintigraphy, clear and rapid tumor imaging was obtained with 200 (Ci of 123I‐labeled ch‐Fab 24 h post‐injection. These results suggest that radioiodine‐labeled chimeric A10 antibodies could potentially be useful candidates for radioimmunotherapy and radio‐immunodetection of pancreatic carcinomas.
The U.S.‐Japan Cooperative Cancer Research Program: Some Highlights of Seminars, Interdisciplinary Program Area, 1981–1996*
Authors: Miller Robert W.
Published: August 2005

Thirty‐one seminars have been held in the 16 years since 1981. A principal interest from the beginning was the genetics of cancer, well before this subject became widely popular. This interest arose in part because of marked binational differences in type‐specific cancer rates, such as the very low rates among Japanese for Hodgkin's disease in the young, testicular cancer, Ewing's sarcoma, superficial spreading melanoma, chronic lymphocytic leukemia, and Wilms’ tumor (half the U.S. frequency). Three seminars were devoted to the seeming reciprocal relationship between B‐cell lymphoma (low in Japan) and certain autoimmune diseases (high in Japan), which is perhaps similar in origin to the male/female differences in the rates for these diseases. A seminar on Li‐Fraumeni syndrome led to the recognition of cases among Japanese pedigrees brought to the meeting, and generated a study of its occurrence in Japanese families with adrenocortical carcinoma in a child. Another seminar revealed a marked clustering of rare cancers in Werner's (premature aging) syndrome in Japan, and led to a binational study and analysis of case‐reports worldwide. Three seminars on pathology heightened appreciation of the importance of subclassifying cancer by subsite and subtype for racial and other comparisons. Four seminars on biostatistics in cancer research generated a substantial exchange of specialists and trainees in this field.
Loss or Somatic Mutations of hMSH2 Occur in Hereditary Nonpolyposis Colorectal Cancers with hMSH2 Germline Mutations
Authors: Lu Shi‐Long , Akiyama Yoshimitsu , Nagasaki Hiromi , Nomizu Tadashi , Ikeda Eiichi , Baba Shozo , Ushio Kyosuke , Iwama Takeo , Maruyama Kazuo , Yuasa Yasuhito
Published: August 2005

Hereditary nonpolyposis colorectal cancer (HNPCC) is a major cancer susceptibility syndrome known to be caused by the inheritance of mutations in DNA mismatch repair genes, such as hMSH2, hMLH1, hPMS1 and hPMS2. To investigate the role of genetic alterations of hMSH2 in HNPCC tumorigenesis, we analyzed 36 Japanese HNPCC kindreds as to hMSH2 germline mutations. Moreover, we also examined somatic mutations of hMSH2 or loss of heterozygosity at or near the hMSH2 locus in the tumors from the hMSH2‐related kindreds. Germline mutations were detected in five HNPCC kindreds (5/36, 14%). Among them, three were nonsense mutations, one was a frameshift mutation and the other was a mutation in an intron where the mutation affected splicing. Loss of heterozygosity in four and somatic mutations in one were detected among the eight tumors with hMSH2 germline mutations. All these alterations were only detected in genomic instability(+) tumors, i.e., not in genomic instability(‐) ones, indicating that mutations of hMSH2 were responsible for at least some of the tumors with genomic instability. These data establish a basis for the presymptomatic diagnosis of HNPCC patients, and constitute further evidence that both DNA mismatch repair genes and tumor suppressor genes may share the same requirement, i.e., two hits are necessary to inactivate the gene function.
Sonodynamically Induced Antitumor Effect of a Gallium‐Porphyrin Complex, ATX‐70
Authors: Yumita Nagahiko , Sasaki Kazuaki , Umemura Shin‐ichiro , Nishigaki Ryuichiro
Published: August 2005

The Sonodynamically induced antitumor effect of a gallium‐porphyrin complex, ATX‐70, was evaluated in mice bearing colon 26. In order to find the optimum timing for the ultrasonic exposure after the administration of ATX‐70, the ATX‐70 concentrations in the plasma, skin, and tumor were measured and analyzed. Antitumor effect was estimated by measuring the tumor size. When used alone, ultrasound showed a slight antitumor effect, which became increasingly significant as the dose of ATX‐70 was increased, while use of ATX‐70 alone had no significant effect. At an ATX‐70 dose of 2.5 mg/kg or higher, the average tumor size decreased to smaller than a half by three days after the ultrasonic exposure. This was smaller than a third of the size of the untreated tumors on the same day. From these results, it is concluded that ATX‐70 significantly sensitizes tumors to ultrasound, demonstrating a synergistic antitumor effect.
Chemopreventive Effect of a Xanthine Oxidase Inhibitor, 1′‐Acetoxychavicol Acetate, on Rat Oral Carcinogenesis
Authors: Ohnishi Masami , Tanaka Takuji , Makita Hiroki , Kawamori Toshihiko , Mori Hideki , Satoh Kumiko , Hara Akira , Murakami Akira , Ohigashi Hajime , Koshimizu Koichi
Published: August 2005

The effect of a xanthine oxidase inhibitor, 1′‐acetoxychavicol acetate (ACA), on 4‐nitroquinoline 1‐oxide (4‐NQO)‐induced oral carcinogenesis was investigated in male F344 rats. All rats except those in the ACA‐alone and untreated groups were given 4‐NQO (20 ppm) in the drinking water for 8 weeks to induce oral cancer. Starting 1 week before the 4‐NQO exposure, animals were fed diet containing 100 ppm or 500 ppm ACA for 10 weeks, followed by the basal diet without ACA for 22 weeks. Other groups were fed the diet containing ACA at 100 ppm or 500 ppm for 22 weeks, starting 1 week after the cessation of 4‐NQO exposure. The remaining groups consisted of rats given 500 ppm ACA alone or untreated rats. At the termination of the experiment (32 weeks), the incidences of tongue neoplasms and preneoplastic lesions, polyamine levels in the tongue tissue, and cell proliferation activity estimated in terms of 5‐bromodeoxyuridine (BrdU)‐labeling index and by morphometric analysis of silver‐stained nucleolar organizer regions’ protein (AgNORs) were compared among the groups. Feeding of ACA at the two doses during initiation or postinitiation significantly decreased the development of tongue carcinoma (93–100% reduction, P< 0.001) and preneoplasia (43–50% reduction for hyperplasia and 34–48% reduction for dysplasia, P<0.05). There were no such lesions in rats fed ACA alone or those in the untreated control group. The number of AgNORs per cell nucleus was significantly decreased by feeding of ACA at a high dose (500 ppm) (29% inhibition, P<0.05). The BrdU‐labeling index was also reduced by dietary administration of ACA (23–32% inhibition, P<0.01). In addition, ACA feeding reduced tongue polyamine levels (35–40% inhibition, P<0.05). These results indicate that ACA inhibited rat oral carcinogenesis, and such inhibition might be related to suppression of cell proliferation in the oral mucosa by the xanthine oxidase inhibitor.
Replication of Hepatitis C Virus in Cultured Non‐neoplastic Human Hepatocytes
Authors: Kato Nobuyuki , Ikeda Masanori , Mizutani Tetsuya , Sugiyama Kazuo , Noguchi Masayuki , Hirohashi Setsuo , Shimotohno Kunitada
Published: August 2005

We established a replication system for hepatitis C virus (HCV) using the PH5CH non‐neoplastic human hepatocyte line that had been immortalized with simian virus 40 large T antigen. In cells inoculated with sera derived from two HCV‐positive blood donors, positive‐stranded HCV RNA was detected up to 30 days postinoculation (p.i.). Semi‐quantitative analysis of HCV RNA revealed that HCV multiplied during the period of culture. Sequence analysis of the HCV hypervariable region 1 (HVR1) in both cases indicated that HVR1 populations from the cells at 8 days p.i. were apparently different from those of the original inocula. HVR1 populations in infected cells became homogeneous or just a few species were selected over time. These results suggest that HCV is replicating in the human hepatocyte PH5CH cells. This culture system will be useful for detailed studies of the biological effects of HCV in human hepatocytes.
Expression of Adhesion Molecules on Myeloma Cells
Authors: Tatsumi Tetsuya , Shimazaki Chihiro , Goto Hideo , Araki Shin‐ichi , Sudo Yoshikazu , Yamagata Noboru , Ashihara Eishi , Inaba Tohru , Fujita Naohisa , Nakagawa Masao
Published: August 2005

We investigated the expression of adhesion molecules including LFA‐1α (CD11a), Mac‐1 (CD11b), LFA‐1β (CD18), VLA‐β1, (CD29), H‐CAM (CD44), VLA‐4 (CD49d), VLA‐5 (CD49e), ICAM‐1 (CD54), N‐CAM (CD56), LFA‐3 (CD58), VNR‐β (CD61), and LECAM‐1 (CD62L) on fresh myeloma cells and human myeloma cell lines. By two‐color flow cytometric analysis with anti‐CD38 antibody, we demonstrated that myeloma cells were located in the strongly CD38‐positive (CD38++) fractions. Fresh myeloma cells were obtained from 28 patients with multiple myeloma (MM) and 3 patients with plasma cell leukemia (PCL). All myeloma cells expressed VLA‐4 on their surface. Most of the myeloma cells also expressed VLA‐5, ICAM‐1, and LFA‐3. H‐CAM was strongly expressed in 3 cases of PCL and 2 cases of aggressive myeloma, and moderately expressed in other MMs. N‐CAM was expressed in 68% of MMs, but none of the 3 PCLs. LFA‐1 was expressed in two cases of aggressive myeloma, but not expressed in other non‐aggressive myelomas. Most of the myeloma cells did not express Mac‐1, VNR‐β, or LECAM‐1. These results suggest that VLA‐4, VLA‐5, ICAM‐1, LFA‐3, and H‐CAM are involved in cellular interaction and migration in MM, and that the expression of N‐CAM and LFA‐1 varies with disease activity in MM.
E‐Cadherin Gene Mutations in Signet Ring Cell Carcinoma of the Stomach
Authors: Muta Hiromi , Noguchi Masayuki , Kanai Yae , Ochiai Atsushi , Nawata Hajime , Hirohashi Setsuo
Published: August 2005

To clarify the significance of E‐cadherin gene alterations in the development of diffuse‐type adenocarcinoma of the stomach, we analyzed mutations of the E‐cadherin gene using the polymerase chain reaction single‐strand conformation polymorphism (PCR‐SSCP) method followed by direct sequencing. Twenty‐two signet ring cell carcinomas of the stomach (10 intramucosal and 12 advanced cancers) were examined. Genomic DNA was extracted separately from cancerous and non‐cancerous tissues and PCR‐SSCP analysis was performed on exons 5 to 9 and the adjacent 30‐ to 40‐base‐pair intron sequences of the E‐cadherin gene. Mobility shifts were found in 2 of the 10 intramucosal cancers. In 2 of the 12 advanced cancers, abnormalities of the E‐cadherin gene were observed in intramucosal lesions as well as in deeply invaded areas. These results indicated that E‐cadherin gene mutations are an early event in the development of signet ring cell carcinoma of the stomach. Direct sequencing revealed that the locations of mutations of the E‐cadherin gene included the branch point sequence in the intron which is responsible for RNA splicing. Reverse transcriptase‐PCR demonstrated aberrant RNA splicing in a case with a branch point mutation, suggesting that branch point mutations play an important role in functional modifications of E‐cadherin in signet ring cell carcinoma of the stomach.
Intragenic Homozygous Deletions of MTS1 Gene in Gastric Cancer in Taiwan
Authors: Wu Ming‐Shiang , Lin Ya‐Wen , Sheu Jin‐Chuan , Wang Hsiu‐Po , Wang Jin‐Town , Shun Chia‐Tung , Lee Wei‐Jei , Wang Teh‐Hong , Lin Jaw‐Town
Published: August 2005

The multiple tumor suppressor 1 (MTS1) and 2 (MTS2) genes, located on chromosome 9p21, have been reported to be deleted or mutated in many malignant cell lines and in a high percentage of some primary carcinomas. To determine whether these genes are altered, and if so, what is the nature of the alterations, in human gastric adenocarcinoma, we investigated their frequency of mutation by Southern blotting, polymerase chain reaction (PCR) and direct sequencing in 55 patients. Furthermore, loss of heterozygosity (LOH) of chromosome 9p21 at the IFNA locus and D9S171 was assessed. Homozygous deletions of exon 1 of the MTS1 gene were identified in 5 of 55 (9.1%) primary tumors. No deletion of MTS2 gene was noted. LOH was observed in 7 (14.3%) of 49 informative cases (5 cases at IFNA locus, 2 cases at D9S171 and one case with combined LOH at D9S171 and homozygous deletion at exon 1 of MTS1). Direct sequencing of PCR products of the MTS1 and MTS2 gene did not reveal any point mutation in these 55 patients. These data indicate that alterations of the MTS1 and MTS2 genes are infrequently encountered. Additional studies of LOH with more micro‐satellite markers near 9p21 are mandatory to elucidate whether another tumor suppressor gene exists in the vicinity of MTS1 in primary gastric adenocarcinoma.
Increased Expression of CD44 Variants in Differentiated Thyroid Cancers
Authors: Takano Toru , Sumizaki Hiromi , Nakano Kouichi , Matsuzuka Fumio , Kuma Kanji , Amino Nobuyuki
Published: August 2005

Expression of CD44 variants in thyroid tumors was analyzed by reverse transcription‐polymerase chain reaction (RT‐PCR) with a fluorescent image analyzer. Increased expression of CD44 variants compared with normal thyroid tissues was observed in most thyroid follicular tumors, especially in follicular carcinomas, poorly differentiated papillary carcinomas and some follicular adenomas. However, variants were hardly detectable in an anaplastic carcinoma. Analysis with restriction enzymes revealed that the major PCR product, consisting of variant bands, was derived from CD44E. Therefore, the expression of CD44E may be associated with the proliferation of differentiated thyroid cells.
Induction by Interleukin‐15 of Human Killer Cell Activity against Lung Cancer Cell Lines and Its Regulatory Mechanisms
Authors: Takeuchi Eiji , Yanagawa Hiroaki , Yano Seiji , Haku Takashi , Sone Saburo
Published: August 2005

Interleukin (IL)‐15 is a novel cytokine with IL‐2‐like activity. In the present study, we examined IL‐15‐mediated induction of killer activity of peripheral blood mononuclear cells (MNC) against lung cancer cell lines, and the regulatory mechanisms of this induction by IL‐15. Cytotoxic activity was measured by 51Cr release assay. IL‐15 at concentrations of more than 10 ng/ml induced significant killer activity of blood MNC against a small cell lung cancer cell line (SBC‐3), as well as Daudi cells, and 50 ng/ml was considered its optimal concentration. A time course study revealed that an incubation period of 4–6 days was optimal for induction of killer activity. MNC cultured with IL‐15 also exhibited killer activity against other lung cancer cell lines (H‐69, N‐291 and PC‐9 cells). IL‐15 and IL‐12 had additive effects on induction of killer activity against SBC‐3 cells. On the other hand, IL‐15 had no synergistic or additive effect on induction of killer activity by IL‐2. Fresh human monocytes isolated by centrifugal elutriation augmented the development of killer activity of lymphocytes stimulated by IL‐15. As a humoral regulatory factor, IL‐4 had a suppressive effect on induction of killer activity by IL‐15. IFN‐γ, IL‐1β, TNF‐α, IL‐6 or IL‐10 had no effect on induction of killer activity by IL‐15 at the optimal concentration. These results suggest that IL‐15 has potential for the immunotherapy of ling cancer.
Overexpression of Cyclin D1 in Rat Esophageal Carcinogenesis Model
Authors: Youssef Emile M. , Hasuma Tadayoshi , Morishima Yoshihiro , Takada Nobuyasu , Osugi Harushi , Higashino Masayuki , Otani Shuzo , Fukushima Shoji
Published: August 2005

Overexpression of cyclin D1 in human esophageal carcinomas has been well documented. The aim of the present study was to assess the expression of cyclin D1 in different types of esophageal epithelial lesions induced by N‐nitrosomethylbenzylamine (NMBA) in rats. A total of 30 rats received s.c.‐injections, five times/week, of 1.0 mg/kg NMBA for a period of 5 weeks followed by the same dose once per week for another 10 weeks. An additional 15 rats were given saline and used as controls to provide normal epithelium. The tumor incidence was 100% at the termination point of 21 weeks. Seventeen rats (57%) showed nuclear staining for cyclin D1, with a great variation in the intensity, as demonstrated by using an immunohistochemical technique. The cyclin D1 positive indices were in the range of 0% to 60% of the individual cells. Negligible staining was observed for normal esophageal epithelium, with a minimal increase in hyperplastic and dysplastic lesions. A significant elevation of cyclin D1 levels was observed in tumors. However, no significant differences were found between papillomas and carcinomas. The immunohistochemical results were confirmed by western blotting analysis. Tumors, papillomas and carcinomas overexpressing cyclin D1 had elevated proliferating cell nuclear antigen (PCNA) indices (P<0.05). The correlation coefficient of overexpressions of PCNA and cyclin D1 was r=0.7 for papillomas, but only r=0.3 for carcinomas. The study thus provides strong evidence of relatively early Overexpression of cyclin D1 during tumorigenesis in the present rat esophageal model. Cyclin D1 expression is not simply a direct consequence of increase cell proliferation.
Effect of Glutathione Depletion on Cisplatin Resistance in Cancer Cells Transfected with the γ‐Glutamylcysteine Synthetase Gene
Authors: Kurokawa Hirokazu , Nishio Kazuto , Ishida Tomoyuki , Arioka Hitoshi , Fukuoka Kazuya , Nomoto Taisuke , Fukumoto Hisao , Yokote Hideyuki , Saijo Nagahiro
Published: August 2005

Overexpression of the human γ‐glutamylcysteine synthetase (γ‐GCS) gene resulted in cisplatin resistance with an increased glutathione (GSH) content, increased ATP‐dependent glutatbione S‐conjugate export pump (GS‐X pump) activity and decreased platinum accumulation in human lung cancer cells transfected with a γ‐GCS cDNA expression vector, as we previously reported. In this study, we examined the effects of buthionine sulfoximine (BSO), a specific inhibitor of γ‐GCS, to determine whether GSH depletion alters cisplatin resistance in a γ‐GCS‐transfected cell line, SBC‐3/ GCS. In the presence of 10 μM BSO for 4 days, SBC‐3/GCS still showed resistance to cisplatin, although it was partially reversed. Under these conditions, GS‐X pump activity remained up‐regulated in spite of low GSH content, and the platinum content was decreased. These data suggest that the GS‐X pump itself influences cisplatin resistance, as well as cellular GSH content.
Correlated Expression of Glutathione S‐Transferase‐π and c‐Jun or Other Oncogene Products in Human Squamous Cell Carcinomas of the Head and Neck: Relevance to Relapse after Radiation Therapy
Authors: Miura Kohki , Suzuki Shinsaku , Tanita Jiro , Shinkawa Hideichi , Satoh Kimihiko , Tsuchida Shigeki
Published: August 2005

The expression of glutathione S‐transferase (GST)‐π and four oncogene products, c‐Jun, c‐Fos, c‐H‐Ras, and c‐Myc, in human squamons cell carcinomas of the head and neck was investigated immunohistochemically before and after radiation therapy, to examine whether these oncogene products might be involved in GST‐π expression, and also to examine the relationship between their expression and therapeutic response. Clinical response to radiation was evaluated in terms of both tumor regression and relapse over two‐year follow‐up periods. The overall positive rates in 83 carcinoma specimens before therapy were 60.2% for GST‐π and 28.9–51.8% for the individual oncogene products, the positive rates for the oncogene products being higher in GST‐π‐positive than in GST‐π‐negative cancers. c‐Jun was most highly correlated with GST‐π expression. Following radiation, the expression of GST‐π and the oncogene products was altered in about a half of 30 patients. Eleven of the 18 patients who exhibited prior positivity for GST‐π showed negative conversion, while 4 of the 12 patients with prior negativity demonstrated positive conversion. In most cases, changes in c‐Jun staining coincided with those in GST‐π. Regarding clinical response to radiation therapy, the positive rates for GST‐π and c‐Jun before radiation were higher in the residual cancer or relapse cases than in the group showing complete response without relapse. Examination of 26 patients with laryngeal cancer revealed that relapse occurred more frequently in cases exhibiting positive reactions for GST‐π,c‐Jun, or c‐H‐Ras. These results suggest a direct link between c‐Jun and GST‐π in head and neck cancers before and after radiation. Although GST‐π and the oncogene products can be influenced by radiation, GST‐π and c‐H‐Ras expression may be a risk factor for relapse of laryngeal cancer.