bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of the interaction between human complement protein C4 and a single‐chain variable fragment antibody by capillary electrophoresis and surface plasmon resonance
Authors: Seifar Reza M. , Cool Robbert H. , Quax Wim J. , Bischoff Rainer
Published: June 2004

Immunoaffinity capillary electrophoresis and surface plasmon resonance have been used for the characterization of the interaction between two large‐sized proteins, the human complement protein C4 and the single‐chain variable fragment C43. The rather high kinetic rate constants as determined by surface plasmon resonance pointed out that a capillary electrophoresis method had to be applied, in which the labeled C4 is preincubated with C43 before injection and the same concentration of C43 is included in the running buffer. Analysis of the concentration dependence of the small mobility shift of the fluorescent C4 signal upon binding of C43 resulted in a dissociation constant that was comparable to the one obtained with surface plasmon resonance. This study is one of the few examples where capillary electrophoresis is successfully used to characterize the interaction between large proteins.
Capillary electrophoresis analysis of a wide variety of seized drugs using the same capillary with dynamic coatings
Authors: Lurie Ira S. , Hays Patrick A. , Parker Kimberly
Published: June 2004

Capillary electrophoresis methodology is presented for the routine analysis of a wide variety of seized drugs using the same capillary with dynamic coatings and multiple run buffers. The types of exhibits analyzed using diode array UV detection include phenethylamines, cocaine, oxycodone, heroin, lysergic acid diethylamide (LSD), opium, hallucinogenic mushrooms, and γ‐hydroxybutyrate‐γ‐butyrolactone (GHB‐GBL). Both qualitative and quantitative analyses are achieved using run buffers that contain additives that provide for secondary equilibrium and/or dynamic coating of the capillary. Dynamic coating of the capillary surface is accomplished by rapid flushes of 0.1 Nsodium hydroxide, water, buffer containing polycation coating reagent, and a buffer containing a polyanionic coating reagent (with or without cyclodextrin(s)) or a micelle coating reagent. Dynamic coating with a polyanionic coating reagent is used for the analysis of moderately basic seized drugs and adulterants. The use of cyclodextrin in the run buffer not only allows for chiral analysis but also greatly enhances separation selectivity for achiral solutes. A capillary dynamically coated with a micelle allows for the analysis of neutral, acidic, and weakly basic drugs (GHB, GBL and neutral, acidic, and weakly basic adulterants). Dynamic coating, which gives rise to a relatively high and robust electroosmotic flow at pH < 7, allows for rapid, precise and reproducible separations. For a wide variety of drugs, excellent linearity and migration time precision and good peak area precision (external and internal standard) is obtained. Quantitative results for synthetic mixtures are in good agreement with actual values. Screening for adulterants is greatly enhanced by the use of automated library searches.
Simultaneous determination of polyamines and catecholamines in PC‐12 tumor cell extracts by capillary electrophoresis with laser‐induced fluorescence detection
Authors: Du Ming , Flanigan Virgil , Ma Yinfa
Published: June 2004

A method to detect polyamines and catecholamines in PC‐12 tumor cell extracts by capillary electrophoresis with laser‐induced fluorescence detection (CE‐LIF) is described for the first time. Both derivatization conditions and buffer concentrations and pH were optimized. Under optimized conditions the polyamines (putresine, spermine, spermidine) and catecholamines (dopamine, norepinephrine, epinephrine, serotonin) were derivatized with fluorescein isothiocyanate and separated at 25 kV in a fused‐silica capillary (50 μm ID×40 cm) with 0.1 M borate, pH 9.0, in less than 18 min. The influence of running buffer conditions, such as buffer pH and concentrations, were also investigated. Linearity of the analytes ranged from 0.05 to 1.0 μmol/L, and the detection limit (S/N = 3 ) ranged from 0.03 to 2.50 nmol/L. The concentrations of polyamines and catecholamines in PC‐12 tumor cell extracts were determined with this method.
Insulator‐based dielectrophoresis for the selective concentration and separation of live bacteria in water
Authors: Lapizco‐Encinas Blanca H. , Simmons Blake A. , Cummings Eric B. , Fintschenko Yolanda
Published: June 2004

Insulator‐based dielectrophoresis (iDEP) was utilized to separate and concentrate selectively mixtures of two species of live bacteria simultaneously. Four species of bacteria were studied: the Gram‐negative Escherichia coli and the Gram‐positive Bacillus subtilis, B. cereus, and B. megaterium. Under an applied direct current (DC) electric field all the bacterial species exhibited negative dielectrophoretic behavior. The dielectrophoretic separations were carried out in a glass microchannel containing an array of insulating posts. The insulating posts in the microchannel produced nonuniformities in the electric field applied along the channel. Mixtures of two species of bacteria were introduced into the microchannel and the electric field was applied. The bacterial species exhibited different dielectrophoretic mobilities under the influence of the nonuniform field. From these experiments a trapping order was established with E. coli trapping at the weakest applied electric field, while the Bacillus species were trapped at different characteristic threshold fields. At stronger applied electric fields, the two different species of bacteria in the microchannel were dielectrophoretically trapped into two spatially distinct bands. The results showed that iDEP has the potential to selectively concentrate and separate different species of bacteria.
A novel microstep device for the size separation of cells
Authors: Vankrunkelsven Sarah , Clicq David , Pappaert Kris , Ranson Willy , De Tandt Cathleen , Ottevaere Heidi , Thienpont Hugo , Baron Gino V. , Desmet Gert
Published: June 2004

We report on a series of preliminary experiments investigating the applicability of a novel method for the size separation of nano‐ and microsized particles and cells. The working principle is based on the application of a shear‐driven flow through stepwise tapered micro‐ or nanochannels. Size separations of mixtures of 0.5 and 1.0 μm carboxylated polystyrene beads as well as of binary mixtures of Staphylococcus aureus and Saccharomyces cerevisiae cells and of S. cerevisiae and Escherichia coli cells are demonstrated.
Nanobiotechnology: From Molecules to Systems
Authors: Klefenz H.
Published: June 2004

Nanobiotechnology is a key enabling multidisciplinary field for medical, technological and biological research and development, medicine, pharmaceutical development, and analytical sciences. Its foundation is the selective integration of a multitude of endeavours, such as biotechnology, chemical and physical nanotechnology, materials sciences, chemistry, engineering, electronics and optronics targeting the construction of micro‐ and nano‐arrays for analyzing complex mixtures of DNA, RNA, proteins, metabolites as well as the design of ultra‐sequencing devices, microbial fuel cells, implantates, molecular motors, artificial organs, and nanorobots. The developments in nanobiotechnology benefit from and contribute to the scientific advances in the chemical and physical nanotechnologies, in particular with respect to materials, composites, nanostructuring techniques, carbon nanotubes, and nanoelectronics.
Production of Laccase by Trametes hirsuta Grown in an Immersion Bioreactor and its Application in the Docolorization of Dyes from a Leather Factory
Authors: Couto S.R. , Sanroman M.A. , Hofer D. , Gübitz G.M.
Published: June 2004

An alternative system for producing laccase on a bioreactor scale by the white‐rot fungus Trametes hirsuta is proposed. The experiments were performed in an immersion bioreactor (employing cuttings of stainless steel sponges as a support) and the culture medium was supplemented with copper sulfate (1 mM). Operating under these conditions, it was possible to obtain a maximum laccase activity of nearly 5,000 U/L within 9 days. In addition, the ability of the crude laccase produced to decolorize two synthetic acid dyes utilized in the leather industry (Luganil Green and Sella Solid Red) was investigated. The effect of the pH and the enzyme activity on decolorization was analyzed. It was found that a pH of 4.0 and a laccase activity of 300 U/L were optimal for Luganil dye decolorization (16.2 % in 2 hours). Sella Solid Red showed its highest decolorization (around 40 % in 2 hours) when used at pH 5.0 and at a laccase activity of 1,000 U/L.
Zinc and Copper Bioaccumulation in Brassica napus at Flowering and Maturation
Authors: Rossi G. , Figliolia A. , Socciarelli S.
Published: June 2004

The aim of this research was to investigate the capability of Brassica napus to bioaccumulate zinc and copper from artificially contaminated soil at the flowering and maturation phenological stage. The trial was set up in a greenhouse and the plants were cultivated in pots. The agricultural soil utilized was contaminated with zinc and copper sulfate (300 and 600 mg/kg, respectively). The soil and plant samples were simultaneously collected during the flowering (8 weeks after seeding) and maturation (harvest time, 13 weeks after seeding) stages, and the heavy metal concentrations were then analyzed. The production of vegetable biomass and the length of the roots were measured. The results showed that B. napus accumulated zinc and copper and translocated these elements in different ways in the harvestable parts of the plants. The zinc bioaccumulation was higher than that of copper. At flowering, zinc was mainly accumulated in the shoots (stems + leaves). Copper was particularly accumulated in the roots, during the entire life cycle. Taking into account the biomass production, the highest heavy metal removal by the shoots (above‐ground parts) occurred at the flowering stage for both zinc and copper. The high bioavailability of zinc and copper in the soil did not severely affect the root length and the biomass production.
Simplified Modeling of Simultaneous Reaction Kinetics of Carbon Oxidation and Nitrification in Biofilm Processes
Authors: Tsuneda S. , Auresenia J. , Hibiya K. , Hirata A.
Published: June 2004

Batch experiments with varying initial substrate concentrations and biomass volumes were performed in a three‐phase fluidized bed biofilm reactor treating simulated domestic wastewater to study the simultaneous carbon oxidation and nitrification in the biofilm process. A simplified mass balance equation for the biofilm was proposed and five different kinetic rate equations were used to match the actual data. The kinetic parameters were obtained by nonlinear regression analysis on a set of two differential equations representing the simultaneous carbon oxidation and nitrification. The competitive inhibition model incorporating the effects of total organic carbon (TOC) concentrations on nitrification rates was the best‐suited model based on the average r2. In this model, oxygen concentration and its affinity constants were not included. Instead, it was assumed that the rate of carbon oxidation is independent of the NH4+‐N, while nitrification is affected by TOC. The number of parameters was successfully minimized without reducing its ability to accurately predict the bulk concentration time course, which would reduce computational complexity and possibly enhance the availability for an actual wastewater treatment process.
Removal of Chromium(VI) Ions from Synthetic Solutions by the Fungus Penicillium purpurogenum
Authors: Say R. , Yilmaz N. , Denizli A.
Published: June 2004

The ability of Penicillium purpurogenum to bind high amounts of chromium(VI) from aqueous solutions is demonstrated. Cr(VI) adsorption capacity increases with time during the first four hours and then leveled off toward the equilibrium adsorption capacity. Biosorption of Cr(VI) ions reached equilibrium in four hours. Binding of Cr(VI) ions with Penicillium purpurogenum biomass was clearly pH dependent. Cr(VI) loading capacity increased with increasing pH. The adsorption of Cr(VI) ions reached a plateau value at a pH of approx. 6.0. The maximum capacity of adsorption of Cr(VI) ions onto the fungal biomass was 36.5 mg/g. Adsorption behavior of Cr(VI) ions can be approximately described with the Langmuir equation. When applying the Langmuir model, the maximum adsorption capacity (Qmax) and the Langmuir constant were found to be 40 mg/g and 3.9 × 10–3 mg/L. Elution of Cr(VI) ions was performed by means of 0.5 M HCl. It was possible to use the biomass of Penicillium purpurogenum for six cycles for biosorption.
Genomic context of paralogous recombination hotspots mediating recurrent NF1 region microdeletion
Authors: Forbes Stephen H. , Dorschner Michael O. , Le Rosalynda , Stephens Karen
Published: June 2004

Recombination between paralogs that flank the NF1 gene at 17q11.2 typically results in a 1.5‐Mb microdeletion that includes NF1 and at least 13 other genes. We show that the principal sequences responsible are two 51‐kb blocks with 97.5% sequence identity (NF1REP‐P1‐51 and NF1REP‐M‐51). These blocks belong to a complex group of paralogs with three components on 17q11.2 and another on 19p13.13. Breakpoint sequencing of deleted chromosomes from multiple patients revealed two paralogous recombination hot spots within the 51‐kb blocks. Lack of sequence similarity between these sites failed to suggest or corroborate any putative cis‐acting recombinogenic motifs. However, the NF1REPs showed relatively high alignment mismatch between recombining paralogs, and we note that the NF1REP hot spots were regions of good alignment bordered by relatively large alignment gaps. Statistical tests for gene conversion detected a single significant tract of perfect match between the NF1REPs that was 700 bp long and coincided with PRS2, the predominant recombination hot spot. Tracts of perfect match occurring by chance may contribute to breakpoint localization, but our result suggests that perfect tracts at recombination hot spots may be a result of gene conversion at sites at which preferential pairing occurs for other, as‐yet‐unknown reasons. © 2004 Wiley‐Liss, Inc.
Black and white women managers: Access to opportunity
Authors: Hite Linda M.
Published: June 2004

This study explores the differing views of Black and White female managers regarding access to key career opportunities for White women and women of color. Items addressed include access to hiring, promotions, key assignments, salary increases, acknowledgment for work, and mentors. Access to each is described by comparing White women and women of color to one another, to White men, and to men of color. Chi‐square analyses of survey responses from the 276 U.S. participants showed that most of the White respondents consistently perceived equal access to career opportunities for women of color. In contrast, most of the Black participants indicated that disparity exists in career opportunities available to women of color compared to White men and women. The implications of these results are discussed.
Invited reaction: Black and white women managers: Access to opportunity
Authors: Higginbotham Elizabeth
Published: June 2004

In a survey of Black and White women managers, Linda M. Hite identifies differences in the managers' perceptions of opportunities available to different race and gender groups. Her findings reveal divergent beliefs about the opportunities for people of color; there is more similarity in Black and White women's views when comparing opportunities for White women and men for getting hired, promoted, receiving salary increases, and other workplace challenges. When making comparisons with either men or women of color, White women are far more optimistic about the opportunities for people of color than are Black women. Hite uses this study to explore the lack of attention to race and racial discrimination among White women, whose views are often assumed to represent all women in management. HRD practice and research can look more closely at the perceptions and experiences of Black women to learn how better to promote their careers, since strategies that increase the number of White women might not be helpful in advancing the careers of Black and other women of color.
Challenges and choices for theoretical research in human resource development
Authors: Torraco Richard J.
Published: June 2004

Theoretical research in HRD has established itself and is now at a point where many avenues exist for further contributions to the field. But what kinds of theoretical research appear to be needed at this stage in the development of HRD? This paper identifies areas in which further research in theory and theory building might be conducted. Possible areas for future research include new HRD theory, theory‐building research methods, HRD's theoretical foundation, and published work that includes both the theory‐building research process and the theory itself. The paper argues that as more theory is being developed, the justification of the need for theory becomes more important. Considering the merits of alternative theoretical contributions, HRD professionals are asked to make judicious choices about the direction of future theoretical research. The implications of this study for further research and professional practice are provided.
The effectiveness of managerial leadership development programs: A meta‐analysis of studies from 1982 to 2001
Authors: Collins Doris B. , Holton Elwood F.
Published: June 2004

Eighty‐three studies from 1982 to 2001 with formal training interventions were integrated via meta‐analytic techniques to determine the effectiveness of interventions in their enhancement of performance, knowledge, and expertise at the individual, team or group, or organizational level. The studies were separated by research design, with the outcome measure of the intervention as the unit of analysis. The effect size for knowledge outcomes ranged from .96 to 1.37; expertise outcomes from .35 to 1.01; and system outcomes averaged .39. Interventions with knowledge outcomes were found to be more effective than in the Burke and Day (1986) meta‐analysis, with the most effective interventions using a single group pretest‐posttest research design. Methodological and conceptual differences in Burke and Day's meta‐analysis on the effectiveness of managerial training make historical comparisons risky. The data suggest that practitioners can attain substantial improvements in both knowledge and skills if sufficient front‐end analysis is conducted to assure that the right development is offered to the right leaders.
Global human resource development: The four C approach
Authors: Petranek Gregory F.
Published: June 2004

The Four C approach defines a method to assist human resource development professionals design strategic global training in a multinational environment. The method was developed from an analysis of published global HRD articles and two books. Four common elements were discovered during the review of the design and development of global HRD. Cooperation, collaboration, communication, and culture are the Four Cs that form the backbone of any global HRD organization. This approach is at the conceptual level with the mechanics of implementation left up to the HRD professional. Each section of the Four Cs presents the definition, discuss application, and summarize implementation. The opinion of the author is presented in the context of instructional system design to facilitate understanding the Four Cs.
Analysis of HLA antigen expression in benign and malignant melanocytic lesions reveals that upregulation of HLA‐G expression correlates with malignant transformation, high inflammatory infiltration and HLA‐A1 genotype
Authors: Ibrahim El Chérif , Aractingi Sélim , Allory Yves , Borrini Francesco , Dupuy Alain , Duvillard Pierre , Carosella Edgardo D. , Avril Marie Françoise , Paul Pascale
Published: June 2004

Previous studies indicate that the nonclassical class I HLA‐G antigen, whose physiologic expression is mainly restricted to placenta, is upregulated in melanoma, renal carcinoma, lung carcinoma, glioblastoma and ovarian carcinoma, where its inhibitory effect on cytotoxic effector cells function is thought to participate in immune evasion by tumor cells. To define whether this expression was a specific feature of melanocytic malignant transformation, 174 paraffin‐embedded melanocytic lesions including naevi, lentigo, primary and metastatic melanomas were analyzed for HLA‐G and other HLA class I and class II antigen expression. HLA‐G antigen expression in melanocytic cells was found to be significantly higher (p < 0.0003) in melanoma (22/79, 28%) than in naevi (1/70, 1.4%), suggesting that upregulation of HLA‐G is associated with malignant transformation in this cell type. Further identification of HLA‐G antigen expression in inflammatory infiltrating cells results in an overall frequency of HLA‐G expressing cells that is higher in melanoma (28/79, 35.5%) than in naevi (5/60, 8.3%) or lentigo (2/23, 8.7%). Upregulation of HLA‐G or HLA class II molecules in melanocytic cells thus appears as a better predictor of malignancy than classical HLA class I antigen defects, which are often described as an important mechanism used by tumor cells to evade immune surveillance. Furthermore, HLA‐G expression was electively found in lesions that exhibited a high inflammatory infiltrate as well as in patients displaying HLA‐A1 genotype. These findings may provide new insights in the comprehension of tumor progression and design of therapeutic approaches aimed at enhancing antitumor immune responses in melanoma patients. © 2003 Wiley‐Liss, Inc.
Rapamycin inhibits cdk4 activation, p 21WAF1/CIP1 expression and G1‐phase progression in transformed mouse fibroblasts
Authors: Gaben Anne‐Marie , Saucier Cecile , Bedin Monique , Barbu Véronique , Mester Jan
Published: June 2004

Rapamycin, a bacterial macrolide antibiotic, is a potent immunosuppressant agent that blocks cell proliferation by inhibiting the G1/S transition in several cell types. In sensitive cells, rapamycin inhibits the phosphorylation of p70 S6K and of Rb; however, the precise mechanisms involved have not been elucidated. In the mouse BP‐A31 fibroblasts, synchronised in G0/G1 phase by serum starvation and induced to reinitiate the G1‐phase progression, rapamycin inhibited the entry into S phase. The effect of rapamycin was situated in early G1 phase. The assembly of the cyclin D1/cdk4 complexes that phosphorylate Rb early in the G1 phase was not modified by the drug. Nevertheless, an inhibition of the activation of cyclin D1/cdk4 and cyclin E/cdk2 as well as of Rb phosphorylation accompanied the cell cycle arrest. Remarkably, rapamycin reduced the level of total p21WAF1/CIP1 as well as that of p21WAF1/CIP1 associated with the cyclin D1/cdk4 complexes. Besides its inhibitory activity toward cdk, p21WAF1/CIP1 has been recently found to participate in the formation/stabilisation/nuclear translocation of cyclin D1/cdk4 complexes. We propose that the inhibition of the expression of p21WAF1/CIP1 is a mechanism by which rapamycin inhibits the triggering of the cdk cascade in the BP‐A31 cells. © 2003 Wiley‐Liss, Inc.
Mutations of BRAF are associated with extensive hMLH1 promoter methylation in sporadic colorectal carcinomas
Authors: Koinuma Koji , Shitoh Kazuhisa , Miyakura Yasuyuki , Furukawa Taiji , Yamashita Yoshihiro , Ota Jun , Ohki Ruri , Choi Young Lim , Wada Tomoaki , Konishi Fumio , Nagai Hideo , Mano Hiroyuki
Published: June 2004

Activating mutations of BRAF have been frequently observed in microsatellite unstable (MSI+) colorectal carcinomas (CRCs), in which mutations of BRAF and KRAS are mutually exclusive. Previously, we reported that hypermethylation of hMLH1 might play an important role in the tumorigenesis of right‐sided sporadic CRCs with MSI showing less frequency of KRAS/TP53 alteration. Therefore, we have assumed that BRAF mutations might be highly associated with hMLH1 methylation status rather than MSI status. In this study, mutations of BRAF and KRAS and their relationship with MSI and hMLH1 methylation status were examined in 140 resected specimens of CRC. The methylation status was classified into 3 types: full methylation (FM), partial methylation (PM) and nonmethylation (NM). Only FM closely linked to reduced expression of hMLH1 protein. BRAF mutations were found in 16 cases (11%), all leading to the production of BRAFV599E. As for MSI status, BRAF mutations were found in 43% of MSI+ and 4% of MSI− cases (p < 0.0001). Among the MSI+ individuals, BRAF mutations were more frequent in cases with hMLH1 deficiency (58%) than those with hMSH2 deficiency (0%; p = 0.02). Moreover, they were found in 69% of FM, 4% of PM and 4% of NM, revealing a striking difference between FM and the other 2 groups (FM vs. PM or NM; p < 0.0001). These findings suggest that BRAF activation may participate in the carcinogenesis of sporadic CRCs with hMLH1 hypermethylation in the proximal colon, independently of KRAS activation. © 2003 Wiley‐Liss, Inc.
Expression of PAX 3 alternatively spliced transcripts and identification of two new isoforms in human tumors of neural crest origin
Authors: Parker Craig J. , Shawcross Susan G. , Li Honggui , Wang Qui‐Yu , Herrington C. Simon , Kumar Shant , MacKie Rhona M. , Prime Wendy , Rennie Ian G. , Sisley Karen , Kumar Patricia
Published: June 2004

The developmental gene PAX 3 is expressed in the early embryo in developing muscle and elements of the nervous system, including the brain. Since no one has investigated the expression of the isoforms of PAX 3 in the neuroectodermal tumors melanoma and small cell lung cancer (SCLC), we have carried out a comprehensive screening for the expression of the isoforms PAX 3a–e using RT‐PCR in human melanoma cell lines, primary human ocular and secondary cutaneous melanomas. We have identified 2 new isoforms of PAX 3, g and h, which we have isolated, cloned and sequenced. Sets of primers for each isoform were designed and their specificity was confirmed by sequence analysis of the products. The isoforms PAX 3a–e were detected in all human cutaneous melanoma cell lines (8/8), but only PAX 3c (1/2) and PAX 3d (2/2) in ocular melanoma cell lines. The same PAX 3 isoforms were detected in more than 80% of human cutaneous melanomas: PAX 3a and b (15/17), PAX 3c (14/17), PAX 3d (16/17) and PAX 3e (15/17). In contrast the results for 7 SCLC cell lines were PAX 3a (0/7), PAX 3b (1/7), PAX 3c (3/7), PAX 3d (6/7), PAX 3e (2/7); 8/8 cutaneous melanoma cell lines and 8/8 ocular melanoma tissues, together with 14/17 cutaneous melanoma tissues screened, expressed the new isoform PAX 3g. All 8 cutaneous melanoma cell lines expressed PAX 3h, but it was not detectable in any of the tumor tissues (0/20). Neither of the 2 ocular melanoma cell lines expressed the 2 new isoforms. Comparison of the different amplicon staining intensities on a gel suggests that PAX 3c and PAX 3d are the predominant transcripts expressed, with relatively low expression of PAX 3e and PAX 3h. We propose that these and the 2 new isoforms we have discovered may be important in oncogenesis and differential diagnosis of melanomas or SCLC. © 2003 Wiley‐Liss, Inc.
An in vitro model to optimize dose scheduling of multimodal radioimmunotherapy and chemotherapy: Effects of p53 expression
Authors: Blumenthal Rosalyn D. , Leone Evelyn , Goldenberg David M. , Rodriguez Marisol , Modrak David
Published: June 2004

Several reports have appeared on the use of combined radioimmunotherapy (RAIT) and chemotherapy. The choice of drug to use with RAIT and how to space the two treatments has not been completely addressed. Because every patient's cancer presents with a specific molecular phenotype, we hypothesized that it may be necessary to tailor therapy based on specific gene expression. We addressed how the form of expression of a single gene, the p53 tumor suppressor, would impact the choice of agents, as well as sequence and spacing of agents. p53 regulates cell cycle arrest to allow for DNA repair after therapy‐induced small DNA damage or induction of apoptosis if damage is great and has been shown to affect chemo‐ and radiosensitivity of cancer cells. We established 3 stable p53 transfectants of the SKOV‐3 p53null parental line (p53wt, p53143mut or p53273mut). p53 expression was confirmed using flow cytometry, using the DO1 pan‐p53 Ab and the PAb240 anti‐p53mut Ab. The colorimetric MTT assay was then used to measure dose‐dependent growth inhibition from single modality chemotherapy (doxorubicin, carboplatin, paclitaxel or topotecan) or radioimmunotherapy (90Y‐RS‐7 IgG anti‐EGP1). The % survival vs. log [drug] were plotted to obtain the IC50. We then used a matrix design in which we varied the sequence of the first and second modality of treatment and the spacing between the 2 treatments to determine the most synergistic and antagonistic combinations for the parental SKOV‐3 and each of the 3 transfectants. The IC50 for each therapeutic agent varied as a function of the form of p53 expressed. For example, of the 4 lines, the p53wt transfectant was the most resistant to topotecan and the 143mut was the most resistant to carboplatin. The 273mut was quite sensitive to both doxorubicin and paclitaxel, whereas the p53null and wt were not. For multimodal treatments, most combinations of RAIT and chemotherapy resulted in a 30–40% growth inhibition (GI) and were either additive or moderately antagonistic. The 3 best (>60% GI) and 3 worst (<25% GI) combinations were identified and were unique to the parental p53null and to the 3 transfectants. Certain combinations showed clear synergy and others were antagonistic, with the first treatment modality blocking the growth inhibitory effects of the second treatment modality. The form of p53 expressed affects chemosensitivity and radiosensitivity and will influence optimal multimodal therapy with RAIT and chemotherapy and the dose‐schedule (sequential with RAIT first or with drug first) when more than 1 agent is used. © 2003 Wiley‐Liss, Inc.
Suppression of 6A8 α‐mannosidase gene expression reduced the potentiality of growth and metastasis of human nasopharyngeal carcinoma
Authors: Yue Wei , Jin Yu Lan , Shi Geng Xian , Liu Yin , Gao Yang , Zhao Fang Tao , Zhu Ling Ping
Published: June 2004

Suppression of α‐mannosidases by chemicals has been shown to reduce the potentiality of growth and metastasis of various tumors. In our study, the effect of 6A8 α‐mannosidase (MAN 6A8), recently discovered in our laboratory, on malignant behaviors of tumor cells was examined. Since the suppressive effect of chemicals on α‐mannosidase is not specific, antisense technique was used to specifically inhibit expression of the MAN 6A8 in human nasopharyngeal carcinoma cells, CNE‐2L2. Two cell clones, AS1 and AS2, with pronounced suppression of MAN 6A8 expression were developed. Wild‐type (W), mock‐transduced (M) and irrelevant DNA‐transduced (IR) CNE‐2L2 cells with normal expression of the enzyme were used as controls. Malignant behaviors of the cells were examined. Significant inhibition of growth of AS cells in vitro measured by MTT assay, colony formation and anchorage‐independent colony formation was found. Pronounced inhibition of formation of tumors from AS cells inoculated into nude mice and metastasis was also observed. W, M and IR cells cultured in plate wells appeared dispersed with a fibroblastic or epithelial morphology, whereas AS cells were in compact sheets with an epithelioid organization. Since E‐cadherin is the key factor in homophilic adhesion of epithelial cells, its expression on the surface of CNE‐2L2 cells was determined. E‐cadherin expression on AS cells was enhanced, whereas it was markedly diminished on W, M and IR cells. In addition, lamellipodia, which play an important role in cell spreading and mobility, almost disappeared on AS cells. The results demonstrate a significant suppressive effect of reduced expression of MAN 6A8 on malignant behaviors of CNE‐2L2 cells. © 2003 Wiley‐Liss, Inc.
Medication use and risk of ovarian carcinoma: A prospective study
Authors: Lacey James V. , Sherman Mark E. , Hartge Patricia , Schatzkin Arthur , Schairer Catherine
Published: June 2004

Inflammation and gonadotropins are hypothesized to influence ovarian carcinogenesis. In a prospective study, we evaluated ovarian cancer risk associated with self‐reported use of medications that influence inflammation or gonadotropin levels. The Breast Cancer Detection Demonstration Project Follow‐Up Study enrolled 61,431 women in 1979 and used telephone interviews and 3 mailed questionnaires through 1998 to update risk factor information and identify incident ovarian cancers. The 1992–95 questionnaire ascertained medication use, including duration and frequency of use for aspirin, acetaminophen, other nonsteroidal anti‐inflammatory drugs (NSAIDs), tranquilizers and histamine‐receptor antagonists. A Poisson regression analysis generated rate ratios (RRs) and 95% confidence intervals (CIs) for the 31,364 women who were at risk of ovarian cancer and responded to the questionnaire that queried regular medication use. One hundred sixteen women developed ovarian cancer during follow‐up. None of the anti‐inflammatory medications was associated with ovarian cancer, but the RR for more than 1 aspirin per day for 1 year or longer was 0.56 (95% CI 0.20–1.5) and the RR for more than 5 years of regular “other NSAID” use was 2.0 (95% CI 0.95–4.2). Regular tranquilizer use was not associated with ovarian cancer, but histamine‐receptor antagonists used regularly for more than 5 years (RR = 3.6, 95% CI 1.4–9.1) or more than once daily (RR = 3.1, 95% CI 1.5–6.5) appeared to increase risk. In our study, neither anti‐inflammatory medications nor anti‐psychotic medications were associated with ovarian cancer. Potential associations with histamine‐receptor antagonists may warrant further study. © 2003 Wiley‐Liss, Inc.
nm23‐H1 reduces in vitro cell migration and the liver metastatic potential of colon cancer cells by regulating myosin light chain phosphorylation
Authors: Suzuki Eiji , Ota Tetsuya , Tsukuda Kazunori , Okita Atsushi , Matsuoka Kinya , Murakami Masakazu , Doihara Hiroyoshi , Shimizu Nobuyoshi
Published: June 2004

The nm23‐H1 gene is known as a potential metastasis suppressor gene in various types of carcinomas. However, the role of nm23‐H1 in colorectal carcinoma still remains controversial and the cellular mechanisms by which its protein may modulate the metastatic phenotype are not yet known. We transfected nm23‐H1 cDNA into the human colon cancer cell line, HT‐29, to test the effects and cellular biological mechanism of nm23 protein in colon cancer. We found that nm23‐H1 strongly inhibited the liver metastasis of HT‐29 cells in nude mice and inhibited the epidermal growth factor (EGF)‐induced cell migration in vitro. Furthermore, we clarified the regulation of the myosin light chain (MLC) phosphorylation by nm23‐H1, which has been demonstrated as having potential role in cell migration. © 2003 Wiley‐Liss, Inc.
Quantitative real‐time RT‐PCR for detection of disseminated tumor cells in peripheral blood of patients with colorectal cancer using different mRNA markers
Authors: Schuster Ronny , Max Nicole , Mann Benno , Heufelder Karin , Thilo Florian , Gröne Jörn , Rokos Franziska , Buhr Heinz‐Johannes , Thiel Eckhard , Keilholz Ulrich
Published: June 2004

The detection of disseminated tumor cells in peripheral blood from colorectal cancer patients by RT‐PCR could be an attractive method for selecting patients for adjuvant therapy. We here report on real‐time RT‐PCR assays (LightCycler) to quantitate potential mRNA markers. We investigated specimens from colon carcinoma and normal colon mucosa tissues, cell lines, blood samples from 129 patients with colorectal cancer (all stages) and 58 reference blood samples (healthy donors, persons suffering from inflammatory bowel or infectious diseases). The expression profile in tissues showed high values for CEA and CK20, whereas in cell lines ProtM was predominant. All markers were detected in reference and patient blood samples (ProtM, 22, 17%; CEA, 84, 86%; CK20, 85, 88%). After quantitative analysis, the definition of cutoff values for each marker and the combination of markers, 13% of patients were judged to have elevated marker concentrations in their blood, from which only 6 had values significantly differing from cutoff value. There were no differences between stages of disease. In the case of 19 patients, investigated prior to and 1 week after surgery, 2 samples revealed a significant postoperative increase in CEA or CK20 mRNA concentration. In spite of high expression levels in tissues and cell lines, we were not able to differentiate satisfyingly mRNA markers originating from tumor cells and those from illegitimate transcription in hematopoetic cells in blood. We conclude that either copy numbers of analyzed markers in circulating tumor cells are not sufficient for detection or, more probably, peripheral blood is not a suitable compartment for detection of tumor cells in colorectal cancer. © 2003 Wiley‐Liss, Inc.
Fruits and vegetables and lung cancer: Findings from the European prospective investigation into cancer and nutrition
Authors: Miller Anthony B. , Altenburg Hans‐Peter , Bueno‐de‐Mesquita Bas , Boshuizen Hendriek C. , Agudo Antonio , Berrino Franco , Gram Inger Torhild , Janson Lars , Linseisen Jacob , Overvad Kim , Rasmuson Torgney , Vineis Paolo , Lukanova Annekatrin , Allen Naomi , Amiano Pilar , Barricarte Aurelio , Berglund Göran , Boeing Heiner , Clavel‐Chapelon Françoise , Day Nicholas E. , Hallmans Göran , Lund Eiliv , Martinez Carmen , Navarro Carmen , Palli Dominico , Panico Salvatore , Peeters Petra H.M. , Quirós José Ramón , Tjønneland Anne , Tumino Rosario , Trichopoulou Antonia , Trichopoulos Dimitrios , Slimani Nadia , Riboli Elio
Published: June 2004

Intake of fruits and vegetables is thought to protect against the development of lung cancer. However, some recent cohort and case‐control studies have shown no protective effect. We have assessed the relation between fruit and vegetable intake and lung cancer incidence in the large prospective investigation on diet and cancer, the European Prospective Investigation Into Cancer and Nutrition (EPIC). We studied data from 478,021 individuals that took part in the EPIC study, who were recruited from 10 European countries and who completed a dietary questionnaire during 1992–1998. Follow‐up was to December 1998 or 1999, but for some centres with active follow‐up to June 2002. During follow‐up, 1,074 participants were reported to have developed lung cancer, of whom 860 were eligible for our analysis. We used the Cox proportional hazard model to determine the effect of fruit and vegetable intake on the incidence of lung cancer. We paid particular attention to adjustment for smoking. Relative risk estimates were obtained using fruit and vegetable intake categorised by sex‐specific, cohort‐wide quintiles. After adjustment for age, smoking, height, weight and gender, there was a significant inverse association between fruit consumption and lung cancer risk: the hazard ratio for the highest quintile of consumption relative to the lowest being 0.60 (95% Confidence Interval 0.46–0.78), p for trend 0.0099. The association was strongest in the Northern Europe centres, and among current smokers at baseline, and was strengthened when the 293 lung cancers diagnosed in the first 2 years of follow‐up were excluded from the analysis. There was no association between vegetable consumption or vegetable subtypes and lung cancer risk. The findings from this analysis can be regarded as re‐enforcing recommendations with regard to enhanced fruit consumption for populations. However, the effect is likely to be small compared to smoking cessation. © 2003 Wiley‐Liss, Inc.
NF‐κB activity blockade impairs the angiogenic potential of human pancreatic cancer cells
Authors: Xiong Henry Q. , Abbruzzese James L. , Lin Edward , Wang Liwei , Zheng Leizhen , Xie Keping
Published: June 2004

The effect of blockade of NF‐κB activity on human pancreatic cancer angiogenesis was determined in an orthotopic xenograft model. Highly metastatic L3.3 human pancreatic cancer cells, which expressed an elevated level of constitutive NF‐κB activity, were transfected with a mutated IκBα (IκBαM). After implantation in the pancreas of nude mice, parental (L3.3) and control vector‐transfected (L3.3‐Neo) cells produced rapidly growing tumors and liver metastases, whereas IκBαM‐transfected (L3.3‐IκBαM) cells had decreased tumorigenicity and metastatic potential. NF‐κB signaling blockade significantly inhibited the in vitro and in vivo expression of the major proangiogenic molecules vascular endothelial growth factor and interleukin‐8 and decreased tumor vascular formation. These events were correlated with retarded tumor growth and suppression of metastasis. Collectively, these data suggest that suppression of tumorigenicity and metastasis by NF‐κB blockade is due to impaired angiogenic potential of tumor cells. © 2003 Wiley‐Liss, Inc.
Frequent somatic mutations of mitochondrial DNA in esophageal squamous cell carcinoma
Authors: Kumimoto Hiroshi , Yamane Yoshihiro , Nishimoto Yoshio , Fukami Hiroko , Shinoda Masayuki , Hatooka Shunzo , Ishizaki Kanji
Published: June 2004

Recent studies of various cancers, such as those of the breast, head and neck, bladder and lung, reported that 46–64% of somatic mutations in the D‐loop region of mitochondrial DNA (mtDNA) are observed. However, in esophageal cancer, only a low rate (5%) of somatic mutations has so far been reported in one article (Hibi, K. et al., Int J Cancer 2001;92:319–321). Thus, to confirm this we analyzed the somatic mutations for hypervariable regions (HVR‐I and HVR‐II) in the D‐loop of mtDNA to reevaluate the possibility of mitochondrial genetic instability in this cancer. We amplified both HVRs by PCR and DNA samples obtained from 38 esophageal tumors and matched normal tissues, and then sequenced them. Comparing the sequences of tumors to those of normal tissues, we found 14 somatic mutations in 13 patients (34.2%). Eleven mutations were at the C consecutive stretch from position 303 to 309 of MITOMAP in the mitochondria databank (http://www.mitomap.org/), 1 at position 215 in HVR‐II and 2 at positions 16,304 and 16,324 in HVR‐I. There were 41 types of germ line variations in HVR‐I including 2 not so far recorded in the mtDNA databank and 17 in HVR‐II including 1 not yet recorded. We also determined nuclear genome instability of these 38 specimens by analyzing 3 independent microsatellite sequences. While 4 specimens showed a single microsatellite change, which is tumor specific, we did not find any co‐relation between a somatic mtDNA mutation and microsatellite instability of nuclear genome DNA. These results suggest that mtDNA mutations might show a genetic instability in esophageal cancer independently from a nuclear genome instability. © 2003 Wiley‐Liss, Inc.
Induction of apoptosis and tumor regression by vesicular stomatitis virus in the presence of gemcitabine in lung cancer
Authors: Li Qiu , Wei Yu‐Quan , Wen Yan‐Jun , Zhao Xia , Tian Ling , Yang Li , Mao Yong‐Qiu , Kan Bing , Wu Yang , Ding Zhen‐Yu , Deng Hong‐Xin , Li Jiong , Luo Yan , Li Hong‐Li , He Qiu‐Ming , Su Jing‐Mei , Xiao Fei , Zou Chun‐Hua , Fu Chun‐Hua , Xie Xing‐Jiang , Yi Tao , Tan Guang‐Hong , Wang Lian , Chen Jing , Liu Jian , Gao Zhen‐Nan
Published: June 2004

Vesicular stomatitis virus (VSV) has been shown to replicate rapidly in vitro and kill selectively a variety of tumor cell lines. The present study was designed to determine whether gemcitabine potentiates the antitumor activity of VSV in vitro and in vivo. A549 human lung adenocarcinoma cells and LLC Lewis lung carcinoma cells were treated with VSV (0.1–10 plaque‐forming units per cell) plus gemcitabine (20 nM to 20 μM). Mice bearing A549 or LLC were treated with VSV (5 × 104 to 1 × 108 plaque‐forming units) daily for 5 days plus gemcitabine (5–125 mg/kg/day) once every 3 days for 4 times. Induction of apoptosis and effects on growth inhibition were assessed. The lung cancer cells treated with VSV plus gemcitabine displayed the apparently increased apoptotic cells compared with treatment with VSV or gemcitabine alone. The combined treatment with VSV plus gemcitabine induced the apparent antitumor activity with complete regression of the established lung cancer in both A549 and LLC lung cancer models and augmented the induction of apoptosis in lung cancer cells in vivo as well. This study suggests that the combined treatment with VSV plus gemcitabine may augment the induction of apoptosis in lung cancer cells in vitro and in vivo, and that the augmented antitumor activity in vivo may result from the increased induction of apoptosis in lung cancer cells. The present findings may be of importance to the further exploration of the potential application of this combined approach in the treatment of lung cancer. © 2004 Wiley‐Liss, Inc.
Reduced expression of MYO18B, a candidate tumor‐suppressor gene on chromosome arm 22q, in ovarian cancer
Authors: Yanaihara Nozomu , Nishioka Michiho , Kohno Takashi , Otsuka Ayaka , Okamoto Aikou , Ochiai Kazunori , Tanaka Tadao , Yokota Jun
Published: June 2004

Allelic imbalance on chromosome arm 22q has been detected in 50–70% of ovarian cancers, suggesting the presence of a tumor‐suppressor gene on this chromosome arm that is involved in ovarian carcinogenesis. Recently, we isolated a candidate tumor‐suppressor gene, MYO18B, at 22q12.1, which is deleted, mutated and hypermethylated in approximately 50% of lung cancers. In our study, we analyzed genetic and epigenetic alterations of the MYO18B gene in ovarian cancers. Missense MYO18B mutations were detected in 1 of 4 (25%) ovarian cancer cell lines and in 1 of 17 (5.9%) primary ovarian cancers. MYO18B expression was reduced in all 4 ovarian cancer cell lines and in 12 of 17 (71%) of primary ovarian cancers. MYO18B expression was restored by treatment with 5‐aza‐2′‐deoxycytidine and/or trichostatin A in 3 of 4 cell lines with reduced MYO18B expression, and hypermethylation of the promoter CpG island for MYO18B was observed in 2 of these 3 cell lines. Its hypermethylation was also observed in 2 of 15 (13%) primary ovarian cancers. Thus, it was indicated that MYO18B expression is reduced in a considerable fraction of ovarian cancers by several mechanisms, including hypermethylation, while the MYO18B gene is mutated in a small subset of ovarian cancers. The present results suggest that MYO18B alterations, including both epigenetic and genetic alterations, play an important role in ovarian carcinogenesis. © 2004 Wiley‐Liss, Inc.