bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of glucose on metabolism and growth of rat glioma cells (C6) in multicellular spheroid culture
Authors: Acker H. , Holtermann G. , Bölling B. , Carlsson J. 
Published: February 2007

AbstractThe metabolism and growth of rat glioma C6 cells in multicellular spheroid culture depended strongly on the glucose supply. A low glucose level (0.1 g/l) in the culture medium reduced lactate production, increased oxygen consumption and diminished hydrogen ion production under normoxia as well as hypoxia. A high glucose level (10 g/l glucose) increased lactate production, had no significant influence on oxygen consumption and increased the hydrogen ion production under hypoxia. Hydrogen ion release from cells under normoxic and hypoxic conditions could be significantly diminished by amiloride (1 mM), indicating the involvement of the Na+/H+ exchanger. The growth of the C6 spheroids was enhanced under low glucose conditions, possibly due to the more physiological extracellular pH in the deeper regions of the spheroids. The growth was inhibited under high glucose conditions, which seemed to be toxic due to a massive hydrogen production giving acidosis. The glucose supply strongly influenced the local hydrogen ion production inside the C6 spheroids and this might in turn lead to changes in the response to different therapeutic modalities. © 1992 Wiley‐Liss, Inc.
Transforming activity and the level of tax protein: Effect of one point mutation in HTLV‐I tax gene
Authors: Sakurai Mamoru , Yamaoka Shoji , Nosaka Tetsuya , Akayama Masayuki , Tanaka Atsushi , Maki Masatoshi , Hatanaka Masakazu 
Published: February 2007

AbstractThe transcriptional trans‐activator molecule of HTLV‐I, Tax, is known to transform rodent fibroblasts. A revertant clone expressing Tax was obtained by treating transformed Rat‐1 cells harboring a single copy of the tax gene with a mutagen. Sequence analysis of the tax gene of the revertant clone revealed that it had one point mutation at codon 12(CTT × TTT), resulting in a change from Leu to Phe. The colony‐forming efficiencies of the cells transfected with the mutant tax gene (mu71tax) were significantly lower than those transfected with the wild‐type by the soft‐agar method. This difference was shown to be due to the instability of mu71Tax. © 1992 Wiley‐Liss, Inc.
The H‐ras oncogene regulates expression of 70‐ and 45‐kDa cell‐surface molecules whose expression correlates with tumor‐cell immunogenicity
Authors: Gopas Jacob , Ehrlich Tali , Cohen Orit , Wishniak Orna , Tainsky Michael A. , Segal Shraga , Rager‐Zisman Bracha , Isakov N. 
Published: February 2007

AbstractThe effects of the H‐ras oncogene on fibroblast cell tumorigenicity and immunogenicity was studied in transfectants of the BALB/c 3T3 clone A31 fibroblastoid cell‐line. Cells that were transfected with MC29‐LTR‐H‐ras (98/6) or MC29‐LTR‐v‐myc + H‐ras (98/4v) and were inoculated into syngeneic BALB/c mice were tumorigenic in 100% and 60% of animals respectively. By contrast, transfectants containing the pSV2neo plasmid alone (98/1) displayed normal characteristics both in vitro and in vivo. Inoculation of mice with mitomycin‐C‐treated 98/1 or 98/4v cells induced an effective protective immunity to a challenge of live 98/4v cells, and a partial immunity against 98/6 cells. Mitomycin‐C‐treated 98/6 cells failed to render immunity against a challenge of either 98/6 or 98/4v cells. To correlate immunogenicity and tumorigenicity of the different cell types with cell‐surface‐antigen expression, we prepared MAbs against 98/4v cells in syngeneic mice. Immunohistochemical and immunoblot analysis revealed that MAbs 102 and 104 recognized 2 protein bands of 70 and 45 kDa respectively, which were expressed predominantly in 98/1 and 98/4v cells. A third immunoreactive protein band of 44 kDa that reacted with MAb 6 was expressed at a similar cell‐surface density on all cell types. Cell‐differentiation‐inducing agents, such as DMSO, retinoic acid or sodium butyrate, were all found to induce 98/6 cell flattening and morphological changes toward a normal phenotype that were followed by up‐regulation of the 70‐ and 45‐kDa antigens. The results suggest that regulation of expression of the 70‐ and 45‐kDa molecules is affected by H‐ras, and that expression of these cell‐surface molecules may be relevant to tumor cell immunogenicity. © 1992 Wiley‐Liss, Inc.
Ornithine decarboxylase assay in human colorectal mucosa. Methodologic issues of importance to quality control
Authors: Garewal Harinder S. , Sloan Donna , Sampliner Richard E. , Fennerty Brian 
Published: February 2007

AbstractOrnithine decarboxylase may be a useful biomarker for risk of neoplasia in colorectal tissues. Investigators have reported enzyme activities varying by as much as 10‐ to 20‐fold using variations of the usual 14CO2 release assay. We have examined the effect of different methodologic factors on calculated ornithine decarboxylase activity. Major effects on the assay result (>20% change) were produced by: (I) use of Tris vs. phosphate buffer, the former yielding 1.5‐ to 4‐fold greater activity; (2) protein content of the reaction mixture with significant error if <50 μg; (3) use of α‐difluoro‐methylornithine‐inhibited blank versus buffer‐only blank. Other changes in assay conditions, including addition of sucrose, detergent, protease inhibitors, specific activity of 14C‐ornithine, the nature of the trapping agent used, and incorporation of a sonication step, did not have a significant effect on ODC quantification (≤20%). Thus, seemingly minor variations in assay conditions can greatly affect the results, which may provide a partial explanation for the variability of ODC activities reported in the literature. Strict quality control measures are mandatory in the interpretation of clinical observations utilizing this marker as an endpoint. © 1992 Wiley‐Liss, Inc.
Secretion of gelatinases and tissue inhibitors of metalloproteinases by human lung cancer cell lines and revertant cell lines: Not an invariant correlation with metastasis
Authors: Zucker Stanley , Lysik Rita M. , Malik Masood , Bauer Brett A. , Caamano J. , Klein‐Szanto Andres J. P. 
Published: February 2007

AbstractNumerous studies have reported a correlation between production of 72‐kDa (MMP‐2) and 92‐kDa (MMP‐9) type‐IV collagenases/gelatinases and the metastatic potential of cancer cells. An abrogating effect of tissue inhibitors of metalloproteinases (TIMP‐1 and TIMP‐2) on metastases has also been noted. In this report we have used sensitive enzyme‐linked immunoas‐says to measure MMP‐2, MMP‐9, TIMP‐1 and TIMP‐2 levels in eight human lung‐cancer cell lines which were characterized for biological behavior in nude mice. We demonstrated that the Calu‐6 and A549 cell lines with the highest metastatic, invasive and tumorigenic potential secreted the highest levels of MMP‐2. MMP‐9 and TIMP‐1 secretions were comparatively low in all cell lines. TIMP‐2 secretion, which exceeded MMP‐2 secretion for all cell lines, did not correlate with metastatic potential. To further explore these correlations, the metastatic Calu‐6 cell line was transfected with a K‐rev‐I cDNA expression construct. The K‐rev revertant cell lines demonstrated a more differentiated phenotype and were less tumorigenic, invasive and metastatic in nude mice. Nonetheless, the Calu‐6 revertant cell lines secreted higher levels of MMP‐2 than the parent cell line. In conclusion, invasion and metastasis by lung‐cancer cells requires not only enhanced MMP production, but also other less well‐understood tumorigenic characteristics. The multiplicity of factors required by cancer cells for dissemination helps to explain the minute fraction of cancer cells from a primary tumor that ever develop into a metastasis. © 1992 Wiley‐Liss, Inc.
A basement‐membrane permeability assay which correlates with the metastatic potential of tumour cells
Authors: Parish Christopher R. , Jakobsen Karen B. , Coombe Deirdre R. 
Published: February 2007

AbstractWe describe an in vitro assay for measuring the ability of tumour cells to permeabilize basement membranes, using transwell chambers coated with the reconstituted basement membrane, matrigel. Unlike previous matrigel‐based procedures which quantified passage of tumour cells across a matrigel barrier, the new assay measures the ability of tumour cells to degrade the basement membrane and increase the diffusion rate of fluorescent (FL) dextran through the barrier. The procedure has the major advantage that permeability can be rapidly and accurately quantified, either by fluorometry or by the use of radiolabelled dextran, thus avoiding tedious and subjective scoring methods. Optimal conditions for the assay are described. In addition, it is demonstrated that the assay can clearly discriminate between metastatic and non‐metastatic tumour cell lines, metastatic tumours permeabilizing the basement membrane and non‐metastatic counterparts failing to do so. A range of enzyme inhibitors suggested that the increase in basement‐membrane permeability caused by the metastatic mammary adenocarcinoma 13762 MAT is probably dependent upon the synergistic action of several degradative enzymes, namely proteases, type‐IV collagenase, and heparanase. Furthermore, the ability to permeabilize the basement membrane was dependent upon intact tumour cells; tumour cell extracts, lysates and supernatants were inactive. © 1992 Wiley‐Liss, Inc.
Isolation of two keratinocyte cell lines derived from HPV‐positive dysplastic vaginal lesions
Authors: Hietanen Sakari , Auvinen Eeva , Grénman Seija , Lakkala Taina , Sajantila Antti , Klemi Pekka , Mäenpää Juhani 
Published: February 2007

AbstractExplant cultures were started from human papillomavirus (HPV)‐infected genital lesions in order to isolate and propagate abnormally differentiating cells from squamous intraepithelial neoplasia. A medium with high calcium concentration was used to induce terminal differentiation of cells from surrounding normal epithelium. Two cell lines with extended life‐spans were established. The UT‐DEC‐I cell line was derived from an HPV‐33‐positive mild vaginal dysplasia (VAIN I). In cultured UT‐DEC‐I cells, HPV 33 DNA was detected with Southern‐blot hybridization and the polymerase chain reaction (PCR) technique. The restriction pattern of HPV 33 changed during early passages and flow cytometric analysis detected a decrease in chromosomal DNA content. HPV 33 RNA from the E6‐E7 region could be amplified by PCR at late passage. UT‐DEC‐2 cell line was derived from an HPV‐16‐positive moderate vaginal dysplasia (VAIN II). HPV 16 DNA was also detected in cultured cells by the PCR technique. The senescence of normal keratinocytes and growth selection in favor of aneuploid cells was observed by flow cytometric analysis at subsequent passages. Karyotype analysis showed clonal chromosomal abnormalities in both cell lines. To date, UT‐DEC‐1 cells have undergone 40 and UT‐DEC‐2 cells 25 passages. This study shows that the isolation of HPV‐infected dysplastic cells can be achieved by culturing the cells in a medium with high calcium concentration. The cell lines presented provide the opportunity of evaluating the early stages of squamous‐cell carcinogenesis. © 1992 Wiley‐Liss, Inc.
Insulin‐like growth factor II in two human colon‐carcinoma cell lines: Gene structure and expression, and protein secretion
Authors: Lambert Sylvie , Carlisi Agnes , Collette Julien , Franchimont Paul , Gol‐Winkler Rosita 
Published: February 2007

AbstractAbnormal expression and structural modification of the IGF‐II gene in correlation with high IGF‐II production have recently been described in human colorectal tumors in comparison with normal adjacent tissues. Here, we have studied IGF‐II in 2 human colon‐carcinoma cell lines, HT29 and COLO 320DM. RFLP analyses revealed no apparent alteration at the IGF‐II locus in these 2 cell lines. HT29 cells weakly expressed IGF‐II mRNA in comparison with the high over‐expression previously observed in some colorectal tumors, and only the 4.8‐kb mRNA species was present. In addition, the serum‐free medium conditioned by HT29 cells contained high IGF‐II levels (approx. 900 ng/ 108 cells), as measured in a specific IGF‐II radioimmunoassay (RIA). After chromatography on Bio‐Gel P‐60, we observed that 64% of the total IGF‐II secreted by HT29 cells were present as a high‐molecular‐weight form of about 17 kDa. In contrast, no detectable expression of the IGF‐II gene was observed in COLO 320DM cells, and low IGF‐II levels were secreted by these cells in the serum‐free medium, with only 9% total IGF‐II represented by the large species. © 1992 Wiley‐Liss, Inc.
Experimental photodynamic therapy with a copper metal vapor laser in colorectal cancer
Authors: Lantz J‐M. , Meyer C. , Saussine C. , Leberquier C. , Heysel F. , Miehe J. , Marescaux J. , Sultan R. , Kedinger M. 
Published: February 2007

AbstractIn an attempt to define the best conditions for an adjunctive treatment of residual colonic microtumors by photodynamic therapy (PDT), an experimental model has been defined. S.c. HT29 colonic‐cancer‐cell tumors grown in nude mice were used and, 48 hr after i.p. administration of 30 mg/kg Photofrin (PH), laser illumination was performed with 75 or 150 Joules/cm2. The efficiencies of 2 lasers, the classically used rhodamine laser (RL) and a copper metal vapor laser (CMVL), were compared. The effects of PDT were assessed by histological and immunocytochemical (detection of a digestive enzyme, dipeptidyl‐peptidase IV, as a marker of cell viability) follow‐up and by the growth curve of the tumors after illumination. We conclude that, although the depth of necrosis resulting from PDT was nearly 3 mm at 75 J/cm2 and nearly 4–5 mm at 150 J/cm2 with both lasers, complete necrosis was obtained only with the CMVL at 150 J/cm2 (in 50% of the tumors). Under the other conditions, a layer of unaffected cells persisted at the pole opposite to laser illumination, resulting in growth curves lower than but parallel to those of the controls. Analysis of drug concentrations in the tumors and various organs, 48 hr after injection, i.e., at the time of laser illumination, revealed the presence of 21 μg/g dry weight PH in the tumors. The tumor vs. host‐organ ratios were equal to or higher than 1 for the small bowel, colon, stomach, lung, skin and muscle. In contrast, the ratios were below 1 for the spleen, pancreas, kidney and liver. © 1992 Wiley‐Liss, Inc.
Characterization of a lung‐cancer‐associated auto‐antigen
Authors: Zeng Carl Q. Y. , Alpert Lesley C. , Alpert Elliot 
Published: February 2007

AbstractAn antigen, protein X (Px), was purified from immune complexes isolated from malignant pleural effusions from patients with adenocarcinoma of the lung by EDTA treatment, PEG 8000 precipitation, protein A affinity chromatography, and Sephadex G‐200 separation in the presence of 3 M NaCl. The purified antigen had a Mr 17,000 by SDS‐PAGE, and consisted of isoelectric species of pl 6.3 and 6.6. Purified Px recombined with Ig isolated from pleural fluids from patients with lung adenocarcinoma, but not with Ig from patients with breast carcinoma. Using an autologous human and heterologous chicken antibody, Px was found, by immunohistology, in the cytoplasm of some of the well‐differentiated lung adenocarcinoma cells, but was not seen in normal lung or a variety of other malignant tissues. A liquid‐phase competitive‐inhibition RIA was developed. Over 30 ng/ml of Px were found in 9 of 15 pleural fluids from patients with lung carcinoma, none of 20 from patients with breast, ovary, stomach or colon cancer, and in 3 of 15 patients with unknown primary tumor. Our data suggest that Px may be a lung‐cancer‐associated autoantigen which can elicit a host humoral response in vivo. © 1992 Wiley‐Liss, Inc.
Carcinogenic effect of tobacco smoking and alcohol drinking on anatomic sites of the oral cavity and oropharynx
Authors: Boffetta Paolo , Mashberg Arthur , Winkelmann Regina , Garfinkel Lawrence 
Published: February 2007

AbstractA series of 359 male patients with 424 cancer lesions of the oral cavity and oropharynx identified at a US Department of Veterans Affairs Medical Center were divided according to site of origin of the lesion and compared with 2,280 controls from the same hospital with respect to exposure to tobacco smoking and alcohol drinking. Sites of origin were: floor of the mouth (153), oral tongue (50), anterior tonsillar pillar (49), soft palate (44), lingual aspect of retromolar trigone (11), alveolar ridge (5), buccal mucosa (4), and hard palate (2). Forty‐one patients had cancers in multiple sites. Tobacco smoking was more strongly associated with soft‐palate lesions than with lesions in more anterior sites. Patients with cancer of floor of the mouth and oral tongue had higher odds ratios for alcohol drinking than subjects with cancers of other sites. This study supports the hypothesis of the carcinogenic effect of tobacco smoke and alcoholic beverages on the oral mucosa through direct contact. © 1992 Wiley‐Liss, Inc.
Expression of the matrix Gla protein in urogenital malignancies
Authors: Levedakou Eleni N. , Strohmeyer Torsten G. , Effert Peter J. , Liu Edison T. 
Published: February 2007

AbstractMatrix Gla protein (MGP), is a vitamin‐K‐dependent protein which is synthesized in a variety of tissues such as lung, heart, kidney, cartilage and bone. The function of MGP in these tissues is unclear. We have previously reported elevated MGP mRNA levels in a breast‐cancer cell line, 600PEI, as compared to normal breast epithelium. Here we describe high MGP expression in primary renal‐cell carcinomas, prostate carcinomas and testicular germ‐cell tumors, as determined by Northern analysis. MGP was over‐expressed in 21 out of 28 patients with renal‐cell carcinoma, and in 16 out of 29 patients with testicular germ‐cell tumors, as compared to matched normal tissues. For the renal‐cell carcinomas, a statistically significant inverse correlation was observed between the level of MGP expression and tumor size, lymph‐node metastasis and tumor grade. MGP was also highly expressed in 13 primary prostatic carcinomas as compared to prostate cell lines derived from metastatic tumors, and to lymph‐node metastasis. Our findings indicate that the loss of MGP expression may be associated with tumor progression and metastasis. © 1992 Wiley‐Liss, Inc.
International variations in the incidence of neuroblastoma
Authors: Stiller C. A. , Parkin D. M. 
Published: February 2007

AbstractThe International Agency for Research on Cancer has coordinated a worldwide study of childhood cancer incidence, with data from over 50 countries. We present here the results for neuroblastoma. In predominantly white Caucasian populations the age‐standardized rate was 7–12 per million, and 6–10% of all childhood cancers were neuroblastomas. Rates were highest in the first year of life (25–50 per million, 30% of total neuroblastoma incidence), and decreased with age to 15–20 per million (50% of the total) at age 1–4, 2–4 per million (15%) at 5–9 and 1–1.5 per million (5%) at 10–14. In the United States, black children had an incidence of 8.5 per million compared with 11.5 among Whites; Blacks tended to be older than Whites at diagnosis. The highest rate in Africa was in Bulawayo, Zimbabwe (8.0 per million) and the lowest in West Nile, Uganda, with no cases registered. Incidence in Israel was similar to that in many white populations, with Jews having a particularly high rate. In other parts of West Asia neuroblastoma had a low relative frequency, suggesting that incidence is low. Rates were also low throughout much of southern and eastern Asia, including India and China. Incidence in Japan was somewhat higher, though less than in Western countries, with the deficit most pronounced in the first year of life; these data relate to the period before mass screening of infants for neuroblastoma in the regions concerned. Incidence was generally higher in regions and among ethnic groups enjoying a higher standard of living, though previous studies within single countries had suggested that neuroblastoma is more common among less affluent groups. Blacks in Africa and the United States may have a weaker genetic predisposition to neuroblastoma, but some of the deficit in many developing countries is likely to be due to under‐diagnosis. © 1992 Wiley‐Liss, Inc.
PCR assay for chromosome 1p deletion in small neuroblastoma samples
Authors: Peter Marline , Michon Jean , Vielh Philippe , Neuenschwander Sylvia , Nakamura Yusuke , Sonsino Elise , Zucker Jean‐Michel , Vergnaud Gilles , Thomas Gilles , Delattre Olivier 
Published: February 2007

AbstractDeletion of the short arm of chromosome I is among the most recurrent cytogenetic alterations found in neuroblastoma and has been associated with short survival. However, this prognostic information, which relies on time‐consuming techniques, is not yet routinely exploited. In order to set up a reliable and simple routine test to determine Ip deletion in neuroblastoma, we have used the polymerase chain reaction to genotype neuroblastoma DNA at 2 loci containing a variable number of tandem repeats and located on the distal part of the short arm of chromosome I. Agarose gel electrophoresis and ethidium bromide staining of the amplification products enable a simple determination of constitutional and tumor genotypes at these loci to be made. A total of 37 samples from 29 patients were studied with this technique. Loss of heterozygosity (LOH) could be identified in 8 cases. In each case the results obtained were in agreement with those achieved by the Southern procedure. This technique will be of particular interest in the pretherapeutic analysis of Ip deletions in small tumor samples obtained by fine‐needle aspirates of the primary tumor. It should also enable retrospective studies from paraffin‐embedded tumor fragments to be made and provide information for the analysis of tumor heterogeneity in neuroblastoma and in other tumors with Ip deletions. © 1992 Wiley‐Liss, Inc.
A population‐based case‐control study of cancers of the nasal cavity and paranasal sinuses in Shanghai
Authors: Zheng Wei , Blot William J. , Shu Xiao‐Ou , Diamond Earl L. , Gao Yu‐Tang , Ji Bu‐Tian , Fraumeni Joseph F. 
Published: February 2007

AbstractA population‐based case‐control study of cancer of the nasal cavity and sinuses, involving interviews of 60 incident cases and 414 controls, was conducted in Shanghai. Cigarette smoking was associated with a mild elevation in risk of squamous‐cell carcinoma but not cancers of other cell types. Occupational exposures to wood and silica dusts and to petroleum products, and the use of wood and straw as cooking fuel, were linked to moderate increases in risk, while 4‐fold or greater increases were associated with a history of chronic nasal diseases, including those occurring 10 or more years prior to cancer diagnosis. Dietary analyses revealed a significant protective effect of consumption of allium vegetables, oranges and tangerines, with a 50% reduced risk of nasal cancer among individuals in the highest intake group of these foods. Consumption of salt‐preserved vegetables, meat and fish was associated with a significantly increased risk of nasal cancer in a dose‐response fashion, with a 5‐fold excess observed for the heaviest intake of these salted foods. These findings suggest that dietary factors may contribute to the development of nasal cancer. © 1992 Wiley‐Liss, Inc.