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B. DRUGS The Vinca alkaloids vinblastine (VLB) and vindesine (VDS), documented MTI known Tubulozole, a synthetic MTI, I3 exists in two isomeric forms: one active, tubulozole-cis (T-C), and one inactive, tubulozole-trans (T-T), on microtubules. T-T has no antiturnor activity. Therefore, tubulozole is a most appropriate compound to use to analyze MTIspecific effects. T-C has been shown to be effective on MO, cellsI4 and on 3LL cells., SCOPUS: ch.b, info:eu-repo/semantics/published

Cancer-associated fibroblasts (CAFs) are increasingly recognised as promoters of tumour progression. It is poorly investigated whether cancer management protocols, such as neoadjuvant radio(chemo)therapy, have an impact on CAFs and, by consequence, on tumour progression. This prompted us to study the impact of neoadjuvant radio(chemo)therapy on the α-SMA/epithelial area ratio in rectal cancer, and the impact of this ratio on recurrence-free survival., SCOPUS: cp.j, info:eu-repo/semantics/published

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Background:Four-and-a-half LIM domains protein 2 (FHL2) is a component of the focal adhesion structures and has been suggested to have a role in cancer progression. It has been shown to be overexpressed in the colorectal cancer (CRC).Methods:Here, we examined a possible prognostic value of FHL2 in CRC. Immunohistochemistry for FHL2 was performed on 296 CRCs without distant metastases at the time of surgery. Staining in the epithelial compartment was quantitatively evaluated using image analysis, and results were related to clinical variables. Antibody specificity was tested using small-interfering RNA transfection in hTERT-immortalised myofibroblasts.Results:Varying degrees of cytoplasmic FHL2 expression by neoplastic epithelial cells were detectable in all cases. Higher FHL2 expression in the epithelial compartment was an independent adverse prognostic factor. Multivariate Cox analysis shows that expression in the tumour invasion front (P<0.001) as well as in the centre of the tumour (P<0.001) was associated with metachronous metastases independently of the clinicopathological variables; expression in the tumour invasion front was also associated with overall survival independently of the clinicopathological variables (P<0.01).Conclusion:Higher FHL2 expression is involved in CRC progression and correlates with the development of metachronous metastases and overall survival, suggesting that FHL2 is an independent adverse prognostic indicator for CRC. © 2013 Cancer Research UK. All rights reserved., SCOPUS: ar.j, info:eu-repo/semantics/published

Tissue integrity is maintained by the stroma in physiology. In cancer, however, tissue invasion is driven by the stroma. Myofibroblasts and cancer-associated fibroblasts are important components of the tumor stroma. The origin of myofibroblasts remains controversial, although fibroblasts and bone marrow-derived precursors are considered to be the main progenitor cells. Myofibroblast reactions also occur in fibrosis. Therefore, we wonder whether nontumorous myofibroblasts have different characteristics and different origins as compared to tumor-associated myofibroblasts. The mutual interaction between cancer cells and myofibroblasts is dependent on multiple invasive growth-promoting factors, through direct cell-cell contacts and paracrine signals. Since fibrosis is a major side effect of radiotherapy, we address the question how the main methods of cancer management, including chemotherapy, hormonotherapy and surgery affect myofibroblasts and by inference the surrogate endpoints invasion and metastasis., Journal Article, Research Support, Non-U.S. Gov't, Review, SCOPUS: sh.j, FLWIN, info:eu-repo/semantics/published

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Members of a family of thyroid cell lines (KAT) were analyzed because they expressed a higher molecular weight (135 kd) form of E-cadherin at their surface. We found that this aberrant E-cadherin is the result of a point mutation in the exon 9 donor splice site causing a skipping of exon 9 with consequent deletion of the corresponding aminoacids on E-cadherin protein. As a spin-off, we report that the various members of the KAT family share this mutation as well as the genetic background. Furthermore we found that this mutated protein leads to disturbed cell-cell adhesion although E-cadherin is still able to mediate the formation of the cadherin/catenin complex. We also demonstrate the presence of another cell-cell adhesion complex, formed by P-cadherin and the catenins. The latter is also not able to mediate cell-cell adhesion. Although these cells lack cell-cell adhesion they are not invasive without exogenous stimulus., SCOPUS: ar.j, info:eu-repo/semantics/published

E-cadherin is involved in the formation of cell-junctions and the maintenance of epithelial integrity. Direct evidence of E-cadherin mutations triggering tumorigenesis has come from the finding of inactivating germline mutations of the gene (CDH1) in hereditary diffuse gastric cancer (HDGC). We screened a series of 66 young gastric cancer probands for germline CDH1 mutations, and two novel missense alterations together with an intronic variant were identified. We then analysed the functional significance of the exonic missense variants found here as well as a third germline missense variant that we previously identified in a HGDC family. cDNAs encoding either the wild-type protein or mutant forms of E-cadherin were stably transfected into CHO (Chinese hamster ovary) E-cadherin-negative cells. Transfected cell-lines were characterized in terms of aggregation, motility and invasion. We show that a proportion of apparently sporadic early-onset diffuse gastric carcinomas are associated with germline alterations of the E-cadherin gene. We also demonstrate that a proportion of missense variants are associated with significant functional consequences, suggesting that our cell model can be used as an adjunct in deciding on the potential pathogenic role of identified E-cadherin germline alterations., SCOPUS: ar.j, info:eu-repo/semantics/published

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Previously an upregulation of E-cadherin and its associated molecules alpha-catenin, beta-catenin and plakoglobin has been demonstrated in clinically overt inflammatory bowel disease (IBD). The aim of this study was to investigate the expression of the E-cadherin/catenin complex in subclinically inflamed bowel mucosa from spondyloarthropathy (SpA) patients., Journal Article, Research Support, Non-U.S. Gov't, info:eu-repo/semantics/published

The E-cadherin-catenin complex is important for the maintenance of epithelial architecture. We studied its expression in Crohn disease, ulcerative colitis, acute ileitis, and controls. Immunohistochemical stainings for E-cadherin, alpha-catenin, beta-catenin and gamma-catenin were performed. E-cadherin messenger RNA (mRNA) was detected using riboprobes. In active inflammation, there was up-regulation of the complex. In particular, epithelium adjacent to ulcers showed increased expression of protein and mRNA, but in ulcer-associated cell lineage, the intensity of staining was weak to negative. In focal inflammation, up-regulation was found in affected areas. Reparative epithelium growing over denuded areas showed weaker expression. Since structural or functional perturbation in any of the molecules of the E-cadherin-catenin complex results in loss of intercellular adhesion, the preexistent epithelium may benefit from up-regulation to try to maintain its normal architecture under inflammatory conditions. Reduced expression in reparative epithelium and ulcer-associated cell lineage could facilitate the motility of these cells., Journal Article, Research Support, Non-U.S. Gov't, info:eu-repo/semantics/published

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Hexadecylphosphocholine (HePC), an experimental and clinical antitumour agent of the alkyllysophospholipid group, was tested for its radiosensitisting effect on a panel of nine human mammary cancer cell lines in vitro. Growth inhibition by ionising radiation and recovery from it were not influenced by pretreatment with HePC in most cases, except for two cell lines expressing an activated ras oncogene. In the latter we found an enhanced radioresistance that was abolished by pretreatment with HePC. Our results suggest that HePC may act as a radiosensitiser for cells carrying an activated ras oncogene. © 1993., SCOPUS: ar.j, info:eu-repo/semantics/published

The alkyllysophospholipid, racemic-1-O-octadecyl-2-O-methylglycero-3-phosphocholine (ET-18-OCH3) was previously shown to inhibit invasion of malignant cells into precultured heart fragments (PHF)in vitro. In particular, pretreatment of PHF with 10 μg ET-18-OCH3 for 48 h was sufficient to induce in the host tissue resistance towards invasion by mouse MO4 cells. Resistance was obvious when MO4 cells were confronted either immediately (the pretreatment experiment) or after withdrawal of the drug 7 days prior to confrontation (the reversibility experiment). In the present study, the survival of PHF cells in the pretreatment and reversibility experiments was similar to that of untreated PHF cells as determined by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) test and by the PHF explantation test. The effective anti-invasive concentration was 6 μg/ml in the pretreatment experiment while 3 μg/ml was sufficient to inhibit invasion in the reversibility experiment. Induction of resistance towards invasion in pretreated PHF was shown to occur not only with MO4 cells but also with mouse LLC-H61 Lewis lung carcinoma and mouse BW-O-Lil T-lymphoma cells. The increase in molecular weight of N-linked cell surface glycosylpeptides (N-GP) of PHF was apparent in the pretreatment experiment and was enhanced in the reversibility experiment. This effect was completely abolished in cells obtained from pretreated PHF which were converted into a cell suspension and further cultured as a monolayer on tissue culture plastic without drug for 7 days. The results reported here provide additional evidence for the causal involvement of N-GP of the PHF host tissue in the anti-invasive activity of ET-18-OCH3in vitro. © 1991 Rapid Communications of Oxford Ltd., SCOPUS: ar.j, info:eu-repo/semantics/published

Cell surface glycans are believed to play a role in tumour invasion and metastasis. Yet, we have previously shown that the inhibitors of N-linked glycan processing swainsonine (SW) and 1-deoxynojirimycin (dNM) did not prevent invasion of chick heart fragments by MO4 murine fibrosarcoma cells in organ culture. We now present biochemical evidence that these and other inhibitors of processing were indeed effective in remodeling glycans, including those expressed at the cell surface. After metabolic labeling with tritiated mannose or fucose, glycosylpeptides were obtained by Pronase treatment of material released from intact cells by trypsin. Glycosylpeptides were separated by Biogel P-10 chromatography. With all drugs tested, there was a shift towards lower molecular weight of the glycan chains. There were, however, major quantitative differences between the different drugs and also, for monensin (MON; 0.1 μg ml-1), between fucose-labeled and mannoselabeled chains. The shift in apparent molecular weight affected mainly fucose-labeled peptides after treatment of MO4 cells with SW (0.4 μg ml-1). The shift induced by dNM (10mM)+SW (0.4 μg ml-1) in both fucosylated and mannosylated chains was much larger than that induced by SW given alone. 1-Deoxymannojirimycin (dMM; 1 mM) had major effects on both mannose and fucose-labeled structures and so did N-methyl-1-deoxynojirimycin (MdNM; 2 mM) and castanospermine (CS; 100 μg ml-1). With the latter drugs, incorporation of fucose in complex-type glycosylpeptides was dramatically reduced. The effect of SW on fucose-labeled glycosylpeptides of embryonic chick heart was similar to that observed on MO4 cells. After removal of sialic acid, control and SW-treated glycosylpeptides from both MO4 and embryonic chick heart cells had similar gel-chromatographic profiles, suggesting that a decrease in cell surface sialic acid accounts to a large extent for the difference between glycans from control and SW-treated cells. Additional biological, SCOPUS: ar.j, info:eu-repo/semantics/published

Human mammary carcinoma cell lines (MCF‐7) were analysed for their hormone sensitivity before and after transfection with a v‐Ha‐ras oncogene or with a neomycin‐resistance gene followed by selection in vitro or in vivo. Our aim was to test how the expression of the ras oncogene would influence the estradiol sensitivity of MCF‐7 cells. In culture, MCF‐7 cells expressing the viral p21 oncogene product, as compared to parental MCF‐7 cells and their control derivatives, showed lower levels of a 67‐kDa estrogen receptor. Progesterone receptors, however, remained sensitive to up‐regulation by estrogens. The oncogene‐expressing cells were less sensitive than all controls to stimulation of proliferation by 10‐8M estradiol or to inhibition of proliferation by 2‐CH3‐4‐OH tamoxifen, and this was not dependent upon the type of culture medium used. After s. c. or i. p. injection into female athymic nude mice, ovariectomized or left intact, the growth of MCF‐7 cells expressing the ras oncogene product and of all control cells was sensitive to stimulation by estrogen supplementation. Conversely, cell lines derived from tumors generated with long latency in untreated athymic nude mice by v‐ras‐expressing MCF‐7 cells showed efficient formation of quickly growing tumors in the absence of estrogen supplementation. No differences were observed in invasion and metastasis of the different MCF‐7 cell types injected into athymic nude mice that were supplemented with estrogens or not. Copyright © 1990 Wiley‐Liss, Inc. A Wiley Company, SCOPUS: ar.j, FLWNA, info:eu-repo/semantics/published

Estramustine (EM) is a conjugate of estradiol and nor-nitrogen mustard (nor-HN2), which is effective in the treatment of prostate cancer. We have compared the effect of EM with that of the known microtubule inhibitor vinblastine (VLB) on the following functions of malignant MO4 mouse cells and of DU-145 human prostate cancer cells in vitro: directional migration, invasion; and the organization and the assembly/disassembly equilibrium of microtubule complexes. The circular area covered by cells migrating from an aggregate explanted on a solid substrate was taken as an index of directional migration. Invasion was studied through confrontation of MO4 or DU-145 cells with fragments of embryonic chick heart in organ culture. Microtubules were investigated immunocytochemically and through immunodetection on protein blots. VLB and EM inhibited directional migration and invasion of MO4 and DU-145 cells in a dose-dependent manner; equimolar combinations of estradiol plus nor-nitrogen mustard did not mimic these effects. At antiinvasive concentrations VLB led to partial disassembly of microtubule complexes, whereas EM resulted in an abnormal pattern of microtubule complexes without alteration of the overall assembly/disassembly equilibrium. Combined treatment with VLB and EM resulted in an enhanced VLB effect, namely complete disassembly. In all tests DU-145 cells were more sensitive to both VLB and EM than were MO4 cells, and the effects were less reversible. The present experiments showed that EM shares an antiinvasive activity with other microtubule inhibitors. © 1988, American Association for Cancer Research. All rights reserved., SCOPUS: ar.j, info:eu-repo/semantics/published