betadex and Colonic-Neoplasms

Methylated β-cyclodextrin (MβCD) can extract cholesterol from lipid rafts and induce apoptosis in cancer cells by inhibiting activation of the PI3K-Akt-Bad pathway. In this study, we modified MβCD with mannose (Man-MβCD) and assessed its in vitro and in vivo potential for targeting colon cancer cells expressing the mannose receptor (MR) and tumor-associated macrophages (TAM). Man-MβCD showed a significantly greater level of cellular association with colon-26 cells and M2 macrophages, and much more prominent anticancer activity than that of MβCD against MR-positive colon-26 cells. These results revealed that autophagy was the main mechanism of cell death associated with Man-MβCD. Furthermore, compared with MβCD, Man-MβCD significantly reduced tumor development following intravenous delivery to tumor-bearing mice, with no apparent side effects. Thus, Man-MβCD has the potential to be a novel anticancer drug.

Topics: Animals; beta-Cyclodextrins; Colonic Neoplasms; Mannose; Mice; Phosphatidylinositol 3-Kinases; Tumor-Associated Macrophages

The complexation of the bioactive compound oxyresveratrol (OXY) with a polymer called cyclodextrin-based nanosponge (CD-NS) and its application was studied.A new methodology is used to calculate, an apparent inclusion complex constant (K

Topics: Antineoplastic Agents; beta-Cyclodextrins; Colonic Neoplasms; HCT116 Cells; Humans; Male; Nanostructures; Plant Extracts; Polymers; Prostatic Neoplasms; Solubility; Stilbenes; Temperature

Aspirin (ASA) has attracted wide interest of numerous scientists worldwide thanks to its chemopreventive and chemotherapeutic effects, particularly in colorectal cancer (CRC). Incorporation of selenium (Se) atom into ASA has greatly increased their anti-tumoral efficacy in CRC compared with the organic counterparts without the Se functionality, such as the promising antitumoral methylseleno-ASA analog (

Topics: Antineoplastic Agents; Aspirin; beta-Cyclodextrins; Cell Proliferation; Colonic Neoplasms; Drug Liberation; HT29 Cells; Humans; Micelles; Poloxamer; Proton Magnetic Resonance Spectroscopy; Solubility; Spectrometry, Fluorescence; Water

Remote loading technology is an outstanding achievement in liposome-based drug delivery systems. Compared with conventional passive loading, remote loading technology exhibits unique superiority in terms of high drug loading efficiency, low leakage rate and adequate drug accumulation. In the intra-liposome aqueous phase, the counterion of the trapping agent can control the state of aggregation/crystallization of the drug-counterion salt, and thereby contribute to control the efficiency of remote loading. Herein, irinotecan (CPT-11)-loaded liposomes were developed using three trapping agents: ammonium sulfate (AS), sulfobutylether-β-cyclodextrin (SBE-β-CD) and sucrose octasulfate (SOS). The corresponding formulations were named as AS liposomal CPT-11, TEA-SBE-β-CD liposomal CPT-11 and TEA-SOS liposomal CPT-11, respectively. Cryo-transmission electron micrographs showed that bundles of CPT-11 fibers were gathered inside TEA-SOS liposomal CPT-11. Furthermore, compared with AS liposomal CPT-11 and TEA-SBE-β-CD liposomal CPT-11, TEA-SOS liposomal CPT-11 demonstrated slower drug release, prolonged circulation time and significantly improved antitumor efficiency. To avoid the protection of ONIVYDE®-related patents, a number of other liposomal CPT-11 formulations are under preclinical investigation or even in clinical trials. Our study gives new insights into the impact of the trapping agent on remote loading, and provides valuable information to evaluate the development of CPT-11 loaded liposomes.

Topics: Ammonium Sulfate; Animals; Antineoplastic Agents; beta-Cyclodextrins; Colonic Neoplasms; Delayed-Action Preparations; Drug Liberation; HT29 Cells; Humans; Irinotecan; Liposomes; Male; Mice, Nude; Rats, Sprague-Dawley; Sucrose; Topoisomerase I Inhibitors

Camptothecin (CPT) is an anti-cancer drug that effectively treats various cancers, including colon cancer. However, poor solubility and other drawbacks have restricted its chemotherapeutic potential. To overcome these restrictions, CPT was encapsulated in CEF (cyclodextrin-EDTA-FE

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; beta-Cyclodextrins; Camptothecin; Colonic Neoplasms; Edetic Acid; Ferric Compounds; G1 Phase; HT29 Cells; Humans; Nanoconjugates

A mucus layer coats the gastrointestinal tract and serves as the first line of intestinal defense against infection. N-acyl-homoserine lactone (AHL) quorum-sensing molecules produced by gram-negative bacteria in the gut can influence the homeostasis of intestinal epithelium. In this study, we investigated the effects of two representative long- and short-chain AHLs, N-3-(oxododecanoyl)-homoserine lactone (C12-HSL) and N-butyryl homoserine lactone (C4-HSL), on cell viability and mucus secretion in LS174T cells. C12-HSL but not C4-HSL significantly decreased cell viability by inducing mitochondrial dysfunction and activating cell apoptosis which led to a decrease in mucin expression. Pretreatment with lipid raft disruptor (Methyl-β-cyclodextrin, MβCD) and oxidative stress inhibitor (N-acetyl-L-cysteine, NAC) slightly rescued the viability of cells damaged by C12-HSL exposure, while the paraoxonase 2 (PON2) inhibitor (Triazolo[4,3-a]quinolone, TQ416) significantly affected recovering cells viability and mucin secretion. When LS174T cells were treated with C12-HSL and TQ416 simultaneously, TQ416 showed the maximal positive effect on cells viability. However, if cells were first treated with C12-HSL for 40 mins, and then TQ46 was added, the TQ416 had no effect on cell viability. These results suggest that the C12-HSL-acid process acts at an early step to activate apoptosis as part of C12-HSL's effect on intestinal mucus barrier function.

Topics: 4-Butyrolactone; Acetylcysteine; Apoptosis; Aryldialkylphosphatase; beta-Cyclodextrins; Cell Line, Tumor; Cell Survival; Colonic Neoplasms; Gene Expression Regulation, Neoplastic; HCT116 Cells; Homoserine; Humans; Microscopy, Electron, Transmission; Mitochondria; Mucin-2; Quorum Sensing

A novel and ultrasensitive sandwich-type electrochemical immunosensor was designed for the quantitative detection of carcino-embryonic antigen (CEA). This immunosensor was developed by using the trimetallic NiAuPt nanoparticles on graphene nanosheets (NGs) nanosheets (NiAuPt-NGs) as excellent labels and β-cyclodextrin functionalized reduced graphene oxide nanosheets (CD-NGs) as the platform. The CD-NGs with high specific surface area good biocompatibility and the ideal dispersibility was used to capture the primary antibodies (Ab1) efficiently. The trimetallic NiAuPt-NGs nanocomposites were used as the labels for signal amplification, showing better electrocatalytic activity towards the reduction of hydrogen peroxide (H2O2), which is much better than that the monometallic Pt-NGs, bimetallic NiPt-NGs and AuPt-NGs due to the synergetic effect presented in NiAuPt-NGs. The NiAuPt-NGs nanocomposites consist of tightly coupled nanostructures of Au, Ni and Pt, which have neither an alloy nor a core-shell structure. Under the optimal conditions, a linear range from 0.001-100 ng/mL and a low detection limit of 0.27 pg/mL were obtained for CEA. The proposed electrochemical sandwich-type immunosensor may have a promising application in bioassay and it enriches the electrochemical immunoassays.

Topics: Antibodies, Immobilized; beta-Cyclodextrins; Biomarkers, Tumor; Biosensing Techniques; Carcinoembryonic Antigen; Colonic Neoplasms; Electrochemical Techniques; Graphite; Humans; Hydrogen Peroxide; Metal Nanoparticles; Nanocomposites; Nickel; Oxidation-Reduction; Platinum; Silver

In present investigation, initially curcumin was complexed with 2-HP-β-CD (curcumin-2-HP-β-CD-complex) in 1:1 ratio and later amalgamated with chitosan microspheres (curcumin-2-HP-β-CD-CMs) for selective delivery in colon only through oral route of administration. Various analytical, spectral and in-silico docking techniques revealed that the curcumin was deeply inserted in the 2-HP-β-CD cavity with apparent stability constant of 3.35×10

Topics: 2-Hydroxypropyl-beta-cyclodextrin; Animals; Area Under Curve; beta-Cyclodextrins; Chitosan; Colon; Colonic Neoplasms; Curcumin; Drug Delivery Systems; Drug Liberation; HT29 Cells; Humans; Male; Metabolic Clearance Rate; Mice; Microscopy, Electron, Scanning; Microspheres; Molecular Dynamics Simulation; Particle Size; Solubility; Spectroscopy, Fourier Transform Infrared; X-Ray Diffraction

Topics: 2-Hydroxypropyl-beta-cyclodextrin; Antineoplastic Agents, Phytogenic; Apoptosis; beta-Cyclodextrins; Clausena; Colonic Neoplasms; Drug Carriers; G2 Phase Cell Cycle Checkpoints; Heterocyclic Compounds, 3-Ring; HT29 Cells; Humans; M Phase Cell Cycle Checkpoints; Mitochondria; Reactive Oxygen Species; Signal Transduction

Polymeric vesicles constructed from cyclodextrin- and azobenzene-grafted poly(glycidyl methacrylate)s showed excellent stability owing to the multiple host-guest complexation. Upon culturing in Na2S2O4-contained buffer solution, cargo-loaded vesicles disassembled, for potential applications in colon-specific drug delivery.

Topics: Azo Compounds; beta-Cyclodextrins; Biocompatible Materials; Cell Line, Tumor; Cell Survival; Colonic Neoplasms; Drug Delivery Systems; Humans; Polymethacrylic Acids

The inclusion complex of GA-13316 with β-cyclodextrin (β-CD) is one of a unique series of gibberellin derivatives possessed of potential anticancer activities. The complex with β-CD was characterized by means of UV, XRD, DSC, TG, (1)H, and 2D NMR spectroscopy. In addition, we investigated the main aspects of the interaction between GA-13316 and β-CD using both experimental and molecular modeling approaches. The complex still maintained its anticancer activity, as shown by in vitro cell survival assay on the human colon carcinoma cell line (HCT116) and the human lung cancer cell line (H460). The results showed that the use of β-CD could be obviously improved the water solubility and stability of GA-13316, implying that the inclusion complex could be a promising future therapeutic agent.

Topics: Antineoplastic Agents; beta-Cyclodextrins; Cell Line, Tumor; Colonic Neoplasms; Gibberellins; Humans; Lung Neoplasms; Magnetic Resonance Spectroscopy; Molecular Docking Simulation; Solubility

To obtain a tumor cell-selectivity of methyl-β-cyclodextrin (M-β-CyD), we newly synthesized folate-appended M-β-CyD (FA-M-β-CyD), and evaluated the potential of FA-M-β-CyD as a novel anticancer agent in vitro and in vivo. Potent antitumor activity and cellular association of FA-M-β-CyD were higher than those of M-β-CyD in KB cells, folate receptor (FR)-positive cells. FA-M-β-CyD drastically inhibited the tumor growth after intratumoral or intravenous injection to FR-positive Colon-26 cells-bearing mice. The antitumor activity of FA-M-β-CyD was comparable and superior to that of doxorubicin after both intratumoral and intravenous administrations, respectively, at the same dose, in the tumor-bearing mice. All of the tumor-bearing mice after an intravenous injection of FA-M-β-CyD survived for at least more than 140 days. Importantly, an intravenous administration of FA-M-β-CyD to tumor-bearing mice did not show any significant change in blood chemistry values. These results strongly suggest that FA-M-β-CyD has the potential as a novel anticancer agent.

Topics: Animals; Antineoplastic Agents; beta-Cyclodextrins; Caspase 3; Caspase 7; Cell Line, Tumor; Cholesterol; Colonic Neoplasms; Doxorubicin; Folic Acid; Hemolysis; Humans; KB Cells; Male; Mice; Mice, Inbred BALB C; Rabbits; Xenograft Model Antitumor Assays

trans-Resveratrol has been proposed to prevent tumor growth and to sensitize cancer cells to anticancer agents. Polyphenol entry into the cells has remained poorly understood. Here, we show that [(3)H]-resveratrol enters colon cancer cells (SW480, SW620, HT29) and leukemia U937 cells through a monensin (5-20 μmol/L) -sensitive process that suggests clathrin-independent endocytosis. Uptake of the molecule can be prevented by methyl-β-cyclodextrin (2-12 mg/mL), nystatin (12 ng/mL), and filipin (1 μg/mL), which all disrupt plasma membrane lipid rafts. Accordingly, radiolabeled resveratrol accumulates in sphingomyelin- and cholesterol-enriched cell fractions. Interestingly, extracellular signal-regulated kinases (ERK), c-Jun NH(2)-terminal kinases (JNK), and Akt also accumulate in lipid rafts on resveratrol exposure (IC(50) at 48 h ≈ 30 μmol/L in SW480 and U937 cells). In these rafts also, resveratrol promotes the recruitment, by the integrin α(V)β(3) (revealed by coimmunoprecipitation with an anti-integrin α(V)β(3) antibody), of signaling molecules that include the FAK (focal adhesion kinase), Fyn, Grb2, Ras, and SOS proteins. Resveratrol-induced activation of downstream signaling pathways and caspase-dependent apoptosis is prevented by endocytosis inhibitors, lipid raft-disrupting molecules, and the integrin antagonist peptide arginine-glycine-aspartate (500 nmol/L). Altogether, these data show the role played by lipid rafts in resveratrol endocytosis and activation of downstream pathways leading to cell death.

Topics: Anti-Bacterial Agents; Antibodies, Monoclonal; Antineoplastic Agents, Phytogenic; Apoptosis; beta-Cyclodextrins; Blotting, Western; Colonic Neoplasms; Endocytosis; Extracellular Signal-Regulated MAP Kinases; Filipin; Flow Cytometry; Focal Adhesion Kinase 1; GRB2 Adaptor Protein; Humans; Immunoenzyme Techniques; Immunoprecipitation; Integrin alphaVbeta3; Membrane Microdomains; Nystatin; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-fyn; ras Proteins; Resveratrol; Signal Transduction; Son of Sevenless Proteins; Stilbenes; Tumor Cells, Cultured

The inhibitory effects of novel prodrugs, inclusion complexes of 3-(4'-geranyloxy-3'-methoxyphenyl)-2-trans propenoic acid (GOFA) and auraptene (AUR) with beta-cyclodextrin (CD), on colon carcinogenesis were investigated using an azoxymethane (AOM)/dextran sodium sulfate (DSS) model. Male CD-1 (ICR) mice initiated with a single intraperitoneal injection of AOM (10 mg/kg body weight) were promoted by the addition of 1.5% (w/v) DSS to their drinking water for 7 days. They were then given a basal diet containing 2 dose levels (100 and 500 ppm) of GOFA/beta-CD or AUR/beta-CD for 15 weeks. At Week 18, the development of colonic adenocarcinoma was significantly inhibited by feeding with GOFA/beta-CD at dose levels of 100 ppm (63% reduction in multiplicity, p < 0.05) and 500 ppm (83% reduction in the multiplicity, p < 0.001), when compared with the AOM/DSS group (multiplicity: 3.36 +/- 3.34). In addition, feeding with 100 and 500 ppm (p < 0.01) of AUR/beta-CD suppressed the development of colonic adenocarcinomas. The dietary administration with GOFA/beta-CD and AUR/beta-CD inhibited colonic inflammation and also modulated proliferation, apoptosis and the expression of several proinflammatory cytokines, such as nuclear factor-kappaB, tumor necrosis factor-alpha, Stat3, NF-E2-related factor 2, interleukin (IL)-6 and IL-1beta, which were induced in the adenocarcinomas. Our findings indicate that GOFA/beta-CD and AUR/beta-CD, especially GOFA/beta-CD, are therefore able to inhibit colitis-related colon carcinogenesis by modulating inflammation, proliferation and the expression of proinflammatory cytokines in mice.

Topics: Animals; beta-Cyclodextrins; Colonic Neoplasms; Colorectal Neoplasms; Coumarins; Diterpenes; Humans; Immunohistochemistry; Incidence; Inflammation; Inflammatory Bowel Diseases; Inhibitor of Apoptosis Proteins; Interleukin-1beta; Interleukin-6; Male; Mice; Mice, Inbred ICR; Microtubule-Associated Proteins; NF-kappa B; Proliferating Cell Nuclear Antigen; Propionates; Repressor Proteins; Survivin; Tumor Necrosis Factor-alpha

Integrin-dependent interaction of epithelial tumor cells with extracellular matrix (ECM) is critical for their migration, but also for hematogenous dissemination. Elevated expression and activity of Src family kinases (SFKs) in colon cancer cells is often required in the disease progression. In this work, we highlighted how focal adhesion kinase (FAK) and SFKs interacted and we analyzed how PI3K/Akt and MAPK/Erk1/2 signaling pathways were activated in early stages of colon cancer cell adhesion. During the first hour, integrin engagement triggered FAK-Y397 phosphorylation and a fraction of FAK was located in lipid rafts/caveolae domains where it interacted with Fyn. The FAK-Y861 and/or -Y925 phosphorylations led to a subsequently FAK translocation out of lipid domains. In parallel, a PI3K/Akt pathway dependent of lipid microdomain integrity was activated. In contrast, the MAPK/Erk1/2 signaling triggered by adhesion increased during at least 4 h and was independent of cholesterol disturbing. Thus, FAK/Fyn interaction in lipid microdomains and a Akt-1 activation occurred at the same time during early contact with ECM suggesting a specific signaling dependent of lipid rafts/caveolae domains.

Topics: beta-Cyclodextrins; Blotting, Western; Caveolae; Cell Adhesion; Cholesterol; Colonic Neoplasms; Focal Adhesion Protein-Tyrosine Kinases; Humans; Immunoprecipitation; Integrins; Membrane Microdomains; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Phosphatidylinositol 3-Kinases; Phosphorylation; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-fyn; Signal Transduction; src-Family Kinases; Transfection; Tumor Cells, Cultured; Tyrosine

To investigate a possible increase of basolateral expression of carcinoembryonic antigen (CEA) by interfering with the apical transport machinery, we studied the effect of cholesterol depletion on CEA sorting and secretion.. Cholesterol depletion was performed in polarized Caco-2 cells using lovastatin and methyl-beta-cyclodextrin.. We show that CEA is predominantly expressed and secreted at the apical surface. Reduction of the cholesterol level of the cell by 40%-50% with lovastatin and methyl-beta-cyclodextrin led to a significant change of the apical-to-basolateral transport ratio towards the basolateral membrane.. As basolateral expression of CEA has been suggested to have anti-inflamatory properties, Cholesterol depletion of enterocytes might be a potential approach to influence the course of inflammatory bowel disease.

Topics: Adenocarcinoma; Anticholesteremic Agents; beta-Cyclodextrins; Biological Transport; Caco-2 Cells; Carcinoembryonic Antigen; Cell Line, Tumor; Cell Membrane; Cholesterol; Colonic Neoplasms; Humans; Inflammatory Bowel Diseases; Lovastatin

A stable 1:1 host-guest complex is formed between a silicon(IV) phthalocyanine conjugated axially with two permethylated beta-cyclodextrin units and a tetrasulfonated porphyrin. The complex exhibits a light-harvesting property and works as an efficient photosensitizing system, killing HT29 human colon adenocarcinoma cells with an IC50 value of 0.09 microM. [structure: see text].

Topics: Adenocarcinoma; beta-Cyclodextrins; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Drug Screening Assays, Antitumor; Humans; Indoles; Isoindoles; Light; Molecular Structure; Organosilicon Compounds; Photochemotherapy; Porphyrins; Water

The present study demonstrates that the functional counter-receptors for E-selectin at the cell surface of Colo201 human colon cancer cells are localized in detergent-insoluble membrane microdomains (DIM). Following isolation of counter-receptors from whole cell lysates using E-selectin-coupled magnetic beads followed by sucrose density gradient separation, both sialyl Lewis a (SLe(a))- and sialyl Lewis x (SLe(x))-carrying glycoproteins which had bound to the E-selectin-beads were distributed in detergent-soluble fractions as well as DIM. In contrast, following isolation of counter-receptors directly from the cell surface, SLe(a)-carrying glycoproteins which had bound to E-selectin-beads at the cell surface were localized only in DIM, together with a Src family kinase, Lyn, while SLe(x)-carrying glycoproteins were not detected in any fraction. The counter-receptors were distributed in a diffuse pattern on the cell surface but clustered following E-selectin binding, leading to the subsequent phosphorylation of extracellular signal-regulated kinase (ERK). Treatment of the cells with methyl-beta-cyclodextrin, a cholesterol-depleting drug, had little effect on either the association of SLe(a)-carrying glycoproteins and Lyn with the domain or ERK phosphorylation. Thus, the functional counter-receptors and Lyn are co-localized in a cholesterol-independent microdomain and create a physiological domain ('glycosynapse') at the cell surface that initiates signalling in cancer cells upon binding to E-selectin.

Topics: beta-Cyclodextrins; Binding Sites; CA-19-9 Antigen; Cell Adhesion; Cell Membrane; Cholesterol; Colonic Neoplasms; E-Selectin; Extracellular Signal-Regulated MAP Kinases; Gangliosides; Humans; Membrane Microdomains; Receptors, Cell Surface; Signal Transduction; Tumor Cells, Cultured

IT-101 is a camptothecin-polymer conjugate prepared by linking camptothecin (CPT) to a hydrophilic, cyclodextrin-based, linear polymer through ester bonds. In previous studies, these polymer conjugates with high molecular weights (ca 90 kDa) have shown significant antitumor effects against human colon carcinoma xenografts. The pharmacokinetics of IT-101 in plasma of rats and its biodistribution in nude mice bearing human LS174T colon carcinoma tumors is reported here.. Sprague-Dawley rats were injected intravenously with three different doses of IT-101. Serial plasma samples were analyzed for polymer-bound and unconjugated CPT by high-performance liquid chromatography (HPLC). Concentration vs time data were modeled using non-compartmentalized methods and compared to CPT alone injected intravenously at an equivalent dose. Tumor-bearing mice were injected intravenously with IT-101 and intraperitoneally with CPT alone, and sacrificed after 24 and 48 h, and serum, heart, liver, spleen, lungs and tumor collected. Tissue samples were extracted and analyzed for polymer-bound and unconjugated CPT by HPLC.. Plasma concentrations and the area under the curve for polymer-bound CPT are approximately 100-fold higher than those of unconjugated CPT or CPT alone, injected intravenously at an equivalent dose. The plasma half-life of IT-101 ranges from 17 -20 h and is significantly greater than that of CPT alone (1.3 h). When CPT is conjugated to polymer, the biodistribution pattern of CPT is different from that taken alone. At 24 h post injection, the total CPT per gram of tissue is the highest in tumor tissue when compared to all other tissues tested. Tumor concentrations of active CPT released from the conjugate are more than 160-fold higher when administered as a polymer conjugate rather than as CPT alone.. The studies presented here indicate that intravenous administration of IT-101, a cyclodextrin based polymer-CPT conjugate, gives prolonged plasma half-life and enhanced distribution to tumor tissue when compared to CPT alone. The data also show that active CPT is released from the conjugate within the tumor for an extended period of time. These effects likely play a significant role in the enhanced antitumor activity of IT-101 when compared to CPT alone or irinotecan.

Topics: Animals; Area Under Curve; beta-Cyclodextrins; Camptothecin; Chromatography, High Pressure Liquid; Colonic Neoplasms; Disease Models, Animal; Female; Half-Life; Humans; Injections, Intraperitoneal; Injections, Intravenous; Mice; Mice, Nude; Polymers; Rats; Rats, Sprague-Dawley; Tissue Distribution; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Regulation of cell surface molecules by matrix metalloproteinases (MMPs), as well as MMPs-catalyzed degradation of extracellular matrix, is important for tumor invasion and metastasis. Our previous study (Kioi, M., Yamamoto, K., Higashi, S., Koshikawa, N., Fujita, K., and Miyazaki, K. (2003) Oncogene 22, 8662-8670) demonstrated that active matrilysin specifically binds to the surface of colon cancer cells and induces notable cell aggregation due to processing of the cell membrane protein(s). Furthermore, these aggregated cells showed a dramatically enhanced metastatic potential. To elucidate the mechanism of matrilysin-induced cell aggregation, we attempted to identify the matrilysin-binding substance on the cell surface. Here, we demonstrate that cholesterol sulfate on the cell surface is a major matrilysin-binding substance. We found that active matrilysin bound to the cell membrane and cholesterol sulfate incorporated into liposomes with similar affinities. Treatment of colon cancer cells with beta-cyclodextrin significantly reduced not only matrilysin binding to the cell surface but also matrilysin-dependent proteolysis and cell aggregation. Interestingly, replenishment of cholesterol sulfate, but not cholesterol, neutralized the effects of beta-cyclodextrin. Taken together, it is likely that binding of matrilysin to cholesterol sulfate facilitates the matrilysin-catalyzed modulation of cell surface proteins, thus inducing the cancer cell aggregation.

Topics: beta-Cyclodextrins; Binding Sites; Carcinogens; Cell Adhesion; Cell Aggregation; Cell Membrane; Cholesterol Esters; Colonic Neoplasms; Humans; Liposomes; Matrix Metalloproteinase 7; Proteins; Tumor Cells, Cultured

The large clostridial cytotoxins toxin A and toxin B from Clostridium difficile are major virulence factors known to cause antibiotic-associated diarrhea and pseudomembranous colitis. Both toxins mono-glucosylate and thereby inactivate small GTPases of the Rho family. Recently, it was reported that toxin B, but not toxin A, induces pore formation in membranes of target cells under acidic conditions. Here, we reassessed data on pore formation of toxin A in cells derived from human colon carcinoma. Treatment of 86Rb+-loaded cells with native or recombinant toxin A resulted in an increased efflux of radioactive cations induced by an acidic pulse. The efficacy of pore formation was dependent on membrane cholesterol, since cholesterol depletion of membranes with methyl-beta-cyclodextrin inhibited 86Rb+ efflux, and cholesterol repletion reconstituted pore-forming activity of toxin A. Similar results were obtained with toxin B. Consistently, methyl-beta-cyclodextrin treatment delayed intoxication of cells in a concentration-dependent manner. In black lipid membranes, toxin A induced ion-permeable pores only in cholesterol containing bilayers and at low pH. In contrast, release of glycosylphosphatidylinositol-anchored structures by phosphatidylinositol specific phospholipase C treatment did not reduce cell sensitivity toward toxins A and B. These data indicate that in colonic cells toxin A induces pore formation in an acidic environment (e.g. endosomes) similar to that reported for toxin B and suggest that pore formation by clostridial glucosylating toxins depends on the presence of cholesterol.

Topics: Animals; Bacterial Toxins; beta-Cyclodextrins; Cell Line; Cell Line, Tumor; CHO Cells; Cholesterol; Clostridioides difficile; Colonic Neoplasms; Cricetinae; Cytotoxins; Dose-Response Relationship, Drug; Enterotoxins; Glycosylphosphatidylinositols; Humans; Hydrogen-Ion Concentration; Lipid Bilayers; Lipids; Peptides; Phosphatidylinositols; Recombinant Proteins; Rubidium; Temperature; Time Factors; Type C Phospholipases

Micellar electrokinetic capillary chromatography (MEKC) with laser-induced fluorescence detection is used for the analysis of three classes of aminophospholipids: phosphatidylethanolamine (PE), phosphatidylserine (PS), and lysophosphatidylethanolamine (LPE) molecular species. 3-(2-Furoyl) quinoline-2-carboxaldehyde (FQ), a fluorogenic dye, was employed for labeling of these phospholipids. The FQ-labeled lipid species were then separated by sodium deoxycholate MEKC modified with methyl-beta-cyclodextrin. Baseline resolution of each class of phospholipids was achieved within 7 min. The migration time in each class increased with the carbon number of their side aliphatic chain. Separation efficiencies of approximately 3x10(5) plates were observed for most of these species. Concentration detection limits (3 sigma) were from 10(-9) to 10(-10) M for PE and LPE species and from 10(-8) to 10(-9) M for PS species. The relative standard deviations for migration time and peak area were less than 0.9% and 4.5%, respectively, for seven PE species. This method was applied to the separation of PE isolated from HT29 human colon cancer cells and roughly 30 PE species were resolved.

Topics: beta-Cyclodextrins; Chromatography, Micellar Electrokinetic Capillary; Colonic Neoplasms; Cyclodextrins; Deoxycholic Acid; Electrophoresis, Capillary; Fluorescent Dyes; Fluorometry; Humans; Indicators and Reagents; Lasers; Lysophospholipids; Phosphatidylethanolamines; Phosphatidylserines; Phospholipids; Sensitivity and Specificity; Tumor Cells, Cultured