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Govindarajan M. Amphiphilic glycoconjugates as potential anti-cancer chemotherapeutics. Eur J Med Chem 2017; 143:1208-1253. [PMID: 29126728 DOI: 10.1016/j.ejmech.2017.10.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 09/14/2017] [Accepted: 10/08/2017] [Indexed: 12/13/2022]
Abstract
Amphiphilicity is one of the desirable features in the process of drug development which improves the biological as well as the pharmacokinetics profile of bioactive molecule. Carbohydrate moieties present in anti-cancer natural products and synthetic molecules influence the amphiphilicity and hence their bioactivity. This review focuses on natural and synthetic amphiphilic anti-cancer glycoconjugates. Different classes of molecules with varying degree of amphiphilicity are covered with discussions on their structure-activity relationship and mechanism of action.
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Affiliation(s)
- Mugunthan Govindarajan
- Emory Institute for Drug Development, Emory University, 954 Gatewood Road, Atlanta, GA 30329, United States.
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2
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Boligan KF, Mesa C, Fernandez LE, von Gunten S. Cancer intelligence acquired (CIA): tumor glycosylation and sialylation codes dismantling antitumor defense. Cell Mol Life Sci 2015; 72:1231-48. [PMID: 25487607 PMCID: PMC11113383 DOI: 10.1007/s00018-014-1799-5] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 11/27/2014] [Accepted: 12/01/2014] [Indexed: 01/28/2023]
Abstract
Aberrant glycosylation is a key feature of malignant transformation and reflects epigenetic and genetic anomalies among the multitude of molecules involved in glycan biosynthesis. Although glycan biosynthesis is not template bound, altered tumor glycosylation is not random, but associated with common glycosylation patterns. Evidence suggests that acquisition of distinct glycosylation patterns evolves from a 'microevolutionary' process conferring advantages in terms of tumor growth, tumor dissemination, and immune escape. Such glycosylation modifications also involve xeno- and hypersialylation. Xeno-autoantigens such as Neu5Gc-gangliosides provide potential targets for immunotherapy. Hypersialylation may display 'enhanced self' to escape immunosurveillance and involves several not mutually exclusive inhibitory pathways that all rely on protein-glycan interactions. A better understanding of tumor 'glycan codes' as deciphered by lectins, such as siglecs, selectins, C-type lectins and galectins, may lead to novel treatment strategies, not only in cancer, but also in autoimmune disease or transplantation.
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Affiliation(s)
- Kayluz Frias Boligan
- Institute of Pharmacology, University of Bern, Friedbühlstrasse 49, 3010, Bern, Switzerland,
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3
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Nanobiotechnology for the Therapeutic Targeting of Cancer Cells in Blood. Cell Mol Bioeng 2015; 8:137-150. [PMID: 25798204 PMCID: PMC4361771 DOI: 10.1007/s12195-015-0381-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Accepted: 01/19/2015] [Indexed: 12/11/2022] Open
Abstract
During metastasis, circulating tumor cells migrate away from a primary tumor via the blood circulation to form secondary tumors in distant organs. Mounting evidence from clinical observations indicates that the number of circulating tumor cells (CTCs) in the blood correlates with the progression of solid tumors before and during chemotherapy. Beyond the well-established role of CTCs as a fluid biopsy, however, the field of targeting CTCs for the prevention or reduction of metastases has just emerged. Conventional cancer therapeutics have a relatively short circulation time in the blood which may render the killing of CTCs inefficient due to reduced exposure of CTCs to drugs. Nevertheless, over the past few decades, the development of nanoparticles and nanoformulations to improve the half-life and release profile of drugs in circulation has rejuvenated certain traditional medicines in the emerging field of CTC neutralization. This review focuses on how the principles of nanomedicine may be applied to target CTCs. Moreover, inspired by the interactions between CTCs and host cells in the blood circulation, novel biomimetic approaches for targeted drug delivery are presented.
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4
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Nanobiotechnology for the Therapeutic Targeting of Cancer Cells in Blood. Cell Mol Bioeng 2015. [DOI: 10.1007/s12195-015-0378-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Abstract
The significant role of platelets and P-selectin in assisting tumor cell metastasis to the lungs has been frequently reported and reviewed. However, evidence recently has come to light on other pro-metastatic mechanisms of platelets beyond that of tumor cell protection from immune cell attack and aiding extravasation, such as promoting epithelial to mesenchymal transition in tumor cells and conveying signals from the primary tumor to distant tissues that optimize conditions for metastasis. Moreover, the role of platelets and selectins in hematogenous metastasis to frequently targeted organs other than the lungs has been less well examined. This review aims to summarize the literature on the roles of platelets in all stages of the metastatic process and to examine the participation of platelets and selectins in hematogenous metastasis to the lungs, liver, bone, and brain. In the light of the available evidence, potential therapeutic avenues for the control of metastasis are also discussed.
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Affiliation(s)
- Lucy A Coupland
- Cancer & Vascular Biology Group, Department of Immuology, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia; Clinical Haematology Unit, The Canberra Hospital, Garran, ACT, Australia
| | - Christopher R Parish
- Cancer & Vascular Biology Group, Department of Immuology, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia.
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Marano G, Gronewold C, Frank M, Merling A, Kliem C, Sauer S, Wiessler M, Frei E, Schwartz-Albiez R. An easily accessible sulfated saccharide mimetic inhibits in vitro human tumor cell adhesion and angiogenesis of vascular endothelial cells. Beilstein J Org Chem 2012; 8:787-803. [PMID: 23015827 PMCID: PMC3388867 DOI: 10.3762/bjoc.8.89] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 05/11/2012] [Indexed: 12/11/2022] Open
Abstract
Oligosaccharides aberrantly expressed on tumor cells influence processes such as cell adhesion and modulation of the cell’s microenvironment resulting in an increased malignancy. Schmidt’s imidate strategy offers an effective method to synthesize libraries of various oligosaccharide mimetics. With the aim to perturb interactions of tumor cells with extracellular matrix proteins and host cells, molecules with 3,4-bis(hydroxymethyl)furan as core structure were synthesized and screened in biological assays for their abilities to interfere in cell adhesion and other steps of the metastatic cascade, such as tumor-induced angiogenesis. The most active compound, (4-{[(β-D-galactopyranosyl)oxy]methyl}furan-3-yl)methyl hydrogen sulfate (GSF), inhibited the activation of matrix-metalloproteinase-2 (MMP-2) as well as migration of the human melanoma cells of the lines WM-115 and WM-266-4 in a two-dimensional migration assay. GSF inhibited completely the adhesion of WM-115 cells to the extracellular matrix (ECM) proteins, fibrinogen and fibronectin. In an in vitro angiogenesis assay with human endothelial cells, GSF very effectively inhibited endothelial tubule formation and sprouting of blood vessels, as well as the adhesion of endothelial cells to ECM proteins. GSF was not cytotoxic at biologically active concentrations; neither were 3,4-bis{[(β-D-galactopyranosyl)oxy]methyl}furan (BGF) nor methyl β-D-galactopyranoside nor 3,4-bis(hydroxymethyl)furan, which were used as controls, eliciting comparable biological activity. In silico modeling experiments, in which binding of GSF to the extracellular domain of the integrin αvβ3 was determined, revealed specific docking of GSF to the same binding site as the natural peptidic ligands of this integrin. The sulfate in the molecule coordinated with one manganese ion in the binding site. These studies show that this chemically easily accessible molecule GSF, synthesized in three steps from 3,4-bis(hydroxymethyl)furan and benzoylated galactose imidate, is nontoxic and antagonizes cell physiological processes in vitro that are important for the dissemination and growth of tumor cells in vivo.
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Affiliation(s)
- Grazia Marano
- German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany ; Calvatis GmbH, Dr.-Albert-Reimann-Str. 16a, 68526 Ladenburg, Germany
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Li J, King MR. Adhesion receptors as therapeutic targets for circulating tumor cells. Front Oncol 2012; 2:79. [PMID: 22837985 PMCID: PMC3402858 DOI: 10.3389/fonc.2012.00079] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 07/07/2012] [Indexed: 12/12/2022] Open
Abstract
Metastasis contributes to >90% of cancer-associated mortality. Though primary tumors can be removed by surgical resection or chemo/radiotherapy, metastatic disease is a great challenge to treatment due to its systemic nature. As metastatic “seeds,” circulating tumor cells (CTCs) are believed to be responsible for dissemination from a primary tumor to anatomically distant organs. Despite the possibility of physical trapping of CTCs in microvessels, recent advances have provided insights into the involvement of a variety of adhesion molecules on CTCs. Such adhesion molecules facilitate direct interaction with the endothelium in specific tissues or indirectly through leukocytes. Importantly, significant progress has been made in understanding how these receptors confer enhanced invasion and survival advantage during hematogenous circulation of CTCs through recruitment of macrophages, neutrophils, platelets, and other cells. This review highlights the identification of novel adhesion molecules and how blocking their function can compromise successful seeding and colonization of CTCs in new microenvironment. Encouraged by existing diagnostic tools to identify and isolate CTCs, strategic targeting of these adhesion molecules to deliver conventional chemotherapeutics or novel apoptotic signals is discussed for the neutralization of CTCs in the circulation.
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Affiliation(s)
- Jiahe Li
- Department of Biomedical Engineering, Cornell University Ithaca, NY, USA
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Jubeli E, Moine L, Vergnaud-Gauduchon J, Barratt G. E-selectin as a target for drug delivery and molecular imaging. J Control Release 2011; 158:194-206. [PMID: 21983284 DOI: 10.1016/j.jconrel.2011.09.084] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 09/22/2011] [Indexed: 01/02/2023]
Abstract
E-selectin, also known as CD62E, is a cell adhesion molecule expressed on endothelial cells activated by cytokines. Like other selectins, it plays an important part in inflammation and in the adhesion of metastatic cancer cells to the endothelium. E-selectin recognizes and binds to sialylated carbohydrates present on the surface proteins of certain leukocytes. E-selectin has been chosen as a target for several therapeutic and medical imaging applications, based on its expression in the vicinity of inflammation, infection or cancer. These systems for drug delivery and molecular imaging include immunoconjugates, liposomes, nanoparticles, and microparticles prepared from a wide range of starting materials including lipids, synthetic polymers, polypeptides and organo-metallic structures. After a brief introduction presenting the selectin family and their implication in physiology and pathology, this review focuses on the formulation of these new delivery systems targeting E-selectin at a molecular level.
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Affiliation(s)
- Emile Jubeli
- Université Paris-Sud 11, Faculté de Pharmacie 5 rue J.B. Clément Chatenay-Malabry, FR 92296, UMR 8612 CNRS, LabEx LERMIT, France
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Paschos KA, Canovas D, Bird NC. The engagement of selectins and their ligands in colorectal cancer liver metastases. J Cell Mol Med 2011; 14:165-74. [PMID: 19627399 PMCID: PMC3837616 DOI: 10.1111/j.1582-4934.2009.00852.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The colonization of the liver by colorectal cancer (CRC) cells is a complicated process which includes many stages, until macrometastases occur. The entrapment of malignant cells within the hepatic sinusoids and their interactions with resident non-parenchymal cells are considered very important for the whole metastatic sequence. In the sinusoids, cell connection and signalling is mediated by multiple cell adhesion molecules, such as the selectins. The three members of the selectin family, E-, P- and L-selectin, in conjunction with sialylated Lewis ligands and CD44 variants, regulate colorectal cell communication and adhesion with platelets, leucocytes, sinusoidal endothelial cells and stellate cells. Their role in CRC liver metastases has been investigated in animal models and human tissue, in vivo and in vitro, in static and shear flow conditions, and their key-function in several molecular pathways has been displayed. Therefore, trials have already commenced aiming to exploit selectins and their ligands in the treatment of benign and malignant diseases. Multiple pharmacological agents have been developed that are being tested for potential therapeutic applications.
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Affiliation(s)
- Konstantinos A Paschos
- Liver Research Group, Section of Oncology, School of Medicine, Royal Hallamshire Hospital, The University of Sheffield, Sheffield, UK.
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Brown JR, Crawford BE, Esko JD. Glycan antagonists and inhibitors: a fount for drug discovery. Crit Rev Biochem Mol Biol 2008; 42:481-515. [PMID: 18066955 DOI: 10.1080/10409230701751611] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Glycans, the carbohydrate chains of glycoproteins, proteoglycans, and glycolipids, represent a relatively unexploited area for drug development compared with other macromolecules. This review describes the major classes of glycans synthesized by animal cells, their mode of assembly, and available inhibitors for blocking their biosynthesis and function. Many of these agents have proven useful for studying the biological activities of glycans in isolated cells, during embryological development, and in physiology. Some are being used to develop drugs for treating metabolic disorders, cancer, and infection, suggesting that glycans are excellent targets for future drug development.
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Masuda Y, Murata Y, Hayashi M, Nanba H. Inhibitory Effect of MD-Fraction on Tumor Metastasis: Involvement of NK Cell Activation and Suppression of Intercellular Adhesion Molecule (ICAM)-1 Expression in Lung Vascular Endothelial Cells. Biol Pharm Bull 2008; 31:1104-8. [DOI: 10.1248/bpb.31.1104] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Yuki Masuda
- Department of Microbial Chemistry, Kobe Pharmaceutical University
| | - Yukihito Murata
- Department of Microbial Chemistry, Kobe Pharmaceutical University
| | | | - Hiroaki Nanba
- Department of Microbial Chemistry, Kobe Pharmaceutical University
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Ogasawara M, Matsunaga T, Suzuki H. Differential effects of antioxidants on the in vitro invasion, growth and lung metastasis of murine colon cancer cells. Biol Pharm Bull 2007; 30:200-4. [PMID: 17202688 DOI: 10.1248/bpb.30.200] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We conducted a comparative study of 20 antioxidants including antioxidative vitamins and polyphenols to examine their inhibitory activities against the in vitro invasion, growth and experimental lung metastasis of murine colon 26-L5 carcinoma cells. Among the compounds tested, epigallocatechin gallate (EGCG), gallocatechin gallate and genistein exhibited significant reductions at 77%, 46% and 44% in tumor metastasis by an intraperitoneal administration for 5 d beginning at 3 d before tumor inoculation, respectively. Quercetin also showed a slight but not statistically significant inhibition. Alpha-tocopherol, beta-carotene, ascorbic acid and 2 EGCG-related compounds of epicatechin gallate and epigallocatechin had no effect. EGCG also inhibited tumor metastasis dose-dependently with 98% suppression at 2 micromol; and an almost equivalent inhibition was also produced by only pre-administration of EGCG at the same dose before tumor inoculation. EGCG significantly inhibited tumor cell invasion and proliferation, but its inhibition of these activities was much less effective than that of other compounds which did not show any antimetastatic effect. No statistically significant relationship was observed between the radical scavenging activities of the test compounds and their rates of inhibition of tumor metastasis. The antimetastatic mechanism of EGCG thus seems to be independent of its inhibition of tumor invasion and growth, as well as its radical scavenging activity. Our results suggest that EGCG is potentially beneficial for tumor metastasis inhibition.
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Affiliation(s)
- Masaru Ogasawara
- Toyama Prefectural Institute for Pharmaceutical Research, Imizu, Japan.
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Lu B, Ding R, Zhang L, Yu X, Huang B, Chen W. Molecular Cloning and Characterization of a Novel Calcium-dependent Protein Kinase Gene IiCPK2 Responsive to Polyploidy from Tetraploid Isatis indigotica. BMB Rep 2006; 39:607-17. [PMID: 17002882 DOI: 10.5483/bmbrep.2006.39.5.607] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A novel calcium-dependent protein kinase gene (designated as IiCPK2) was cloned from tetraploid Isatis indigotica. The full-length cDNA of IiCPK2 was 2585 bp long with an open reading frame (ORF) of 1878 bp encoding a polypeptide of 625 amino acid residues. The predicted IiCPK2 polypeptide included three domains: a kinase domain, a junction domain (or autoinhibitory region), and a C-terminal calmodulin-like domain (or calcium-binding domain), which presented a typical structure of plant CDPKs. Further analysis of IiCPK2 genomic DNA revealed that it contained 7 exons, 6 introns and the length of most exons was highly conserved. Semi-quantitative RTPCR revealed that the expression of IiCPK2 in root, stem and leaf were much higher in tetraploid sample than that in diploid progenitor. Further expression analysis revealed that gibberellin (GA3), NaCl and cold treatments could upregulate the IiCPK2 transcription. All our findings suggest that IiCPK2 might participate in the cold, high salinity and GA3 responsive pathways.
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Affiliation(s)
- Beibei Lu
- Department of pharmacognosy, School of Pharmacy, Second Military Medical University, Shanghai 200433, China
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Dube DH, Bertozzi CR. Glycans in cancer and inflammation--potential for therapeutics and diagnostics. Nat Rev Drug Discov 2005; 4:477-88. [PMID: 15931257 DOI: 10.1038/nrd1751] [Citation(s) in RCA: 1225] [Impact Index Per Article: 64.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Changes in glycosylation are often a hallmark of disease states. For example, cancer cells frequently display glycans at different levels or with fundamentally different structures than those observed on normal cells. This phenomenon was first described in the early 1970s, but the molecular details underlying such transformations were poorly understood. In the past decade advances in genomics, proteomics and mass spectrometry have enabled the association of specific glycan structures with disease states. In some cases, the functional significance of disease-associated changes in glycosylation has been revealed. This review highlights changes in glycosylation associated with cancer and chronic inflammation and new therapeutic and diagnostic strategies that are based on the underlying glycobiology.
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Affiliation(s)
- Danielle H Dube
- Department of Chemistry, University of California, Berkeley, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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Zeisig R, Stahn R, Wenzel K, Behrens D, Fichtner I. Effect of sialyl Lewis X-glycoliposomes on the inhibition of E-selectin-mediated tumour cell adhesion in vitro. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2004; 1660:31-40. [PMID: 14757218 DOI: 10.1016/j.bbamem.2003.10.014] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of this study was to evaluate the potential of different types of sialyl Lewis X-conjugated liposomes as competitive inhibitors for tumour cell adhesion to endothelial E-selectin. Sterically stabilised liposomes with the sLeX ligand at the terminal end of the polyethyleneglycol (PEG) chain, as well as vesicles that had the ligand embedded within the PEG-layer, were compared to ligand-bearing liposomes without sterical stabilisation. First, 14 different tumour cell lines were characterised for their expression of sialyl Lewis X and/or A. Tumour cell adhesion was characterised in three static assays in vitro using: (i) immobilised E-selectin, (ii) CHO cells, transfected to express E-selectin and (iii) human umbilical vein endothelial cells (HUVEC). Sterically stabilised liposomes with the ligand at the terminal end of the polyethylene chain were the most effective inhibitors in all three assays and inhibited the adhesion of HT29 colon- and Lewis lung (LL) carcinoma cells by about 60-80%. The binding was not affected by a PEG-coating of the liposomes. Sterical stabilisation, on the other hand, completely prevented macrophage uptake (J774 cell line) independently of the presence of the ligand, while plain liposomes were taken up in an amount of 5.4 nmol liposomal lipids/10(6) macrophages.
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Affiliation(s)
- Reinhard Zeisig
- Max-Delbrück-Center for Molecular Medicine, 13092 Berlin-Buch, PF 74 02 38 AG Experimental Pharmacology, 13125 Berlin, Germany.
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Schuldes H, Schleicher D, Mayer G, Markus BH, Cinatl J, Blaheta RA. Binding of gastrointestinal tumor cells to endothelial E- and P-selectin adhesion receptors leads to transient down-regulation of sLeX ligands in vitro. Int J Colorectal Dis 2003; 18:292-9. [PMID: 12774243 DOI: 10.1007/s00384-002-0465-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/12/2002] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND AIMS The prognostic relevance of sialyl Lewis X (sLeX) expression in colorectal and gastric cancer and its relevance to the hematogenous phase of tumor invasion is controversial. This study was designed to evaluate sLeX expression during tumor cell-endothelial cell interaction in vitro. METHODS Adhesion and transendothelial penetration of MKN45, PaCa-2, WiDr, or Dan-G cells was analyzed by combined phase contrast-reflection interference contrast microscopy. In parallel, kinetics of membranous sLeX expression were examined fluorimetrically. To identify factor(s) which may be responsible for sLeX expression during tumor invasion tumor cells were treated with soluble immunomodulators, isolated endothelial plasma membranes, or E-selectin or P-selectin IgG fusion proteins. sLeX was then analyzed by flow cytometry. RESULTS Fluorometric quantification of sLeX demonstrated an inverse correlation between basal sLeX expression level and adhesion capacity of the tumor cells. Unexpectedly, sLeX was strongly down-regulated on tumor cell membranes in the course of heterophilic cell-cell contacts. The process occurred transiently, with a maximum effect 30-60 min after introducing tumor cells to the endothelial monolayer. Binding of tumor cells to immobilized E- and P-selectin IgG globulin chimeras was shown to be responsible for this phenomenon. CONCLUSION A transient loss of sLeX is necessary for gastrointestinal tumor cells to invade endothelial cells. Due to the transient nature of the decrease in sLeX the controversy about the prognostic relevance of sLeX expression in colorectal and gastric cancer may be rooted in the stage of tumor invasion at the time of sLeX measurement.
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Affiliation(s)
- Horst Schuldes
- Klinik für Urologie und Kinderurologie, St.-Katharinen-Hospital Frechen GmbH, Akademisches Lehrkrankenhaus, Universität zu Köln, Cologne, Germany
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