betadex and Carcinoma--Squamous-Cell

The activity of chlorin e6 (Ce6) in photodynamic therapy of cancers is significantly reduced by its propensity to form aggregates. It was postulated that disaggregation of Ce6 could be achieved with the use of hydroxypropyl-beta-cyclodextrin (HP-β-CD) through solubility enhancement.. An initial phase solubility study of Ce6 was conducted with various concentrations of HP-β-CD at three different pH conditions, i.e. pH 3, pH 5 and pH 7. Solubility-induced disaggregation of Ce6 was illustrated by fluorescence spectroscopy and singlet oxygen generation studies. Interaction between Ce6 and HP-β-CD was further demonstrated by solid-state characterization techniques. Inclusion complex formulations were tested for improved efficacy on squamous cancer cell lines.. Increase in Ce6 solubility was observed, especially at pH 7, indicating the formation of inclusion complex between Ce6 and HP-β-CD. This resulted in disaggregation of Ce6 aggregates illustrated by fluorescence spectroscopy. The mode of binding was predominated by H-bonding supported by temperature-dependent binding studies and molecular simulation work. The inclusion complex demonstrated improved photodynamic efficacy through enhanced singlet oxygen generation and phototoxicity on human oral squamous carcinoma cells.. pH-dependent complexation between Ce6- and HP-β-CD-induced disaggregation of Ce6 aggregates and the resultant formulations facilitated improved PDT efficacy on tested cancer cell lines.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; beta-Cyclodextrins; Calorimetry, Differential Scanning; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Survival; Chlorophyllides; Crystallography, X-Ray; Dose-Response Relationship, Drug; Drug Compounding; Head and Neck Neoplasms; Humans; Hydrogen-Ion Concentration; Models, Molecular; Mouth Neoplasms; Photochemotherapy; Photosensitizing Agents; Porphyrins; Powder Diffraction; Singlet Oxygen; Solubility; Spectrometry, Fluorescence; Spectroscopy, Fourier Transform Infrared; Squamous Cell Carcinoma of Head and Neck; Thermodynamics; Time Factors

We have developed herein an engineered polymer-based nanoplatform showing the convergence of two-photon fluorescence imaging and bimodal phototherapeutic activity in a single nanostructure. It was achieved through the appropriate choice of three different components: a β-cyclodextrin-based polymer acting as a suitable carrier, a zinc phthalocyanine emitting red fluorescence simultaneously as being a singlet oxygen ((1)O2) photosensitizer, and a tailored nitroaniline derivative, functioning as a nitric oxide (NO) photodonor. The self-assembly of these components results in photoactivable nanoparticles, approximately 35 nm in diameter, coencapsulating a multifunctional cargo, which can be delivered to carcinoma cells. The combination of steady-state and time-resolved spectroscopic and photochemical techniques shows that the two photoresponsive guests do not interfere with each other while being enclosed in their supramolecular container and can thus be operated in parallel under control of light stimuli. Specifically, two-photon fluorescence microscopy allows mapping of the nanoassembly, here applied to epidermal cancer cells. By detecting the red emission from the phthalocyanine fluorophore it was also possible to investigate the tissue distribution after topical delivery onto human skin ex vivo. Irradiation of the nanoassembly with visible light triggers the simultaneous delivery of cytotoxic (1)O2 and NO, resulting in an amplified cell photomortality due to a combinatory effect of the two cytotoxic agents. The potential of dual therapeutic photodynamic action and two-photon fluorescence imaging capability in a single nanostructure make this system an appealing candidate for further studies in biomedical research.

Topics: Antineoplastic Agents; beta-Cyclodextrins; Biocompatible Materials; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Cell Survival; Drug Carriers; Drug Screening Assays, Antitumor; Epichlorohydrin; Humans; Indoles; Isoindoles; Microscopy, Fluorescence; Molecular Structure; Nanoparticles; Nitric Oxide; Organometallic Compounds; Photons; Photosensitizing Agents; Polymers; Singlet Oxygen; Skin Neoplasms; Zinc Compounds

Low aqueous solubility of porphyrin-based photosensitizers hampers their clinical use in photodynamic therapy because of complex delivery. In this study, we explore meso-tetra(m-hydroxyphenyl)-21,23H-porphyrin (mTHPP), a potent photosensitizer, covalently attached to β-cyclodextrin (CD-mTHPP) with a focus on topical delivery and cellular uptake. The photophysical properties of CD-mTHPP were examined using steady-state fluorescence and lifetime measurements verifying increased aqueous solubility. Confocal and fluorescence lifetime imaging microscopy on human squamous carcinoma cells (A431) evidenced a cytoplasmic uptake of CD-mTHPP in predominantly monomeric form. CD-mTHPP was also delivered to human skin ex vivo and the skin penetration was assessed using two-photon fluorescence microscopy. The results indicated that CD-mTHPP exhibits improved skin distribution compared to mTHPP alone using aqueous vehicles. Thus the CD-mTHPP conjugate demonstrates improved biodistribution ex vivo compared to mTHPP and is a promising multimodal system for photodynamic therapy.

Topics: beta-Cyclodextrins; Biological Transport, Active; Carcinoma, Squamous Cell; Cell Line, Tumor; Female; Humans; In Vitro Techniques; Microscopy, Fluorescence, Multiphoton; Photochemical Processes; Photochemotherapy; Photosensitizing Agents; Porphyrins; Skin; Solubility; Spectrometry, Fluorescence; Spectrophotometry; Water

Oral squamous cell carcinoma (OSCC) develops slowly and it is usually preceded by identifiable oral preneoplastic lesions (OPLs): chemoprevention could be a promising approach. Resveratrol (RV) is a plant-based agent characterized by a strong in vitro antineoplastic action, but this effect has not been clinically confirmed owing to its metabolic inactivation. In order to circumvent this limitation and to improve RV efficacy, it was locally applied and complexed with a protective and solubilising vehicle (2-hydroxypropyl-beta-cyclodextrin, HPbetaCD). The experimentation was performed in vitro on 7,12-dimethylbenz[a]anthracene-induced hamster OSCC cell line (HCPC I) and in vivo in the related animal model, by comparison of two RV-HPbetaCD formulations (cream and mouthwash) and RV alone. Vehicles and RV-formulations were free from toxicity. Antiproliferative action of RV on HCPC I was concentration- and time-dependent, and was improved in HPbetaCD-formulations. In vivo, RV prevented OPL and OSCC appearance and growth. Here, too, HPbetaCD-formulations (mainly mouthwash) demonstrated the best chemopreventive effects in terms of lesions prevalence, multiplicity, dimension, and histological signs of malignancy. HPLC detection of RV corroborated that its action is concentration-correlated and is improved by its inclusion in HPbetaCDs. In summary, our study demonstrates that RV is effective in the chemoprevention of DMBA-induced oral carcinogenesis and when it is complexed with HPbetaCDs its efficacy is significantly improved.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; 9,10-Dimethyl-1,2-benzanthracene; Administration, Topical; Animals; Anticarcinogenic Agents; beta-Cyclodextrins; Carcinogens; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Transformation, Neoplastic; Cheek; Cricetinae; Drug Combinations; Mesocricetus; Mouth Neoplasms; Pharmaceutical Vehicles; Resveratrol; Stilbenes

Lipid rafts are cholesterol-enriched microdomains in the plasma membrane. They act as molecular platforms that spatially organize membrane receptor molecules and are involved in the transduction of various signaling pathways. We recently reported that in the radiosensitive squamous cell carcinoma SCC61 line, gamma-irradiation results in a rearrangement of the plasma membrane rafts and signaling platforms leading to radiation-induced apoptosis in a ceramide-dependent pathway. By contrast, this reorganization was found to be defective in the radioresistant counterpart cell line, SQ20B. As the cholesterol content of lipid rafts is two times higher in SQ20B compared with SCC61 cells, we investigated the modulation of these microdomains using methyl-beta-cyclodextrin (MbetaCDX), a widely used cholesterol-depleting agent, in order to disrupt raft organization in both cells. Here, we report that MbetaCDX treatment resulted in the triggering of apoptosis in SCC61 cells involving mitochondrial events and associated with the clustering of Fas, the formation of Fas-FADD complexes and the cleavage of procaspase 8. The ligand-independent activation of this death receptor was totally absent in SQ20B cells, which remained resistant to MbetaCDX-triggered apoptosis. However, treatment of SQ20B with MbetaCDX resulted in a ligand-independent activation of the epidermal growth factor receptor (EGFR) survival pathway, as evidenced by an increased tyrosine phosphorylation of EGFR. Taken altogether, our results indicate that lipid raft integrity is intimately involved in the triggering of apoptotic cell death and/or survival pathways in head and neck carcinoma cells.

Topics: Apoptosis; beta-Cyclodextrins; Carcinoma, Squamous Cell; Cell Line, Tumor; Cholesterol; ErbB Receptors; fas Receptor; Head and Neck Neoplasms; Humans; Membrane Microdomains; Signal Transduction

Cholesterol is an essential constituent of cell membranes and the regulation of cholesterol concentration is critical for cell functions including signaling. In this paper, we applied resonant waveguide grating (RWG) biosensor to study the cellular functions of cholesterol through real time monitoring the dynamic mass redistribution (DMR) mediated by cholesterol depletion with methyl-beta-cyclodextrin (mbetaCD). In A431 cells, depletion of cholesterol by mbetaCD led to a DMR signature that was similar, but not identical to that induced by epidermal growth factor (EGF). To elucidate the cellular mechanisms of the DMR signal mediated by cholesterol depletion, a panel of modulators that specifically modulate the activities of various cellular targets were used to pretreat the cells. Results showed that the DMR signals triggered by cholesterol depletion are primarily linked to the transactivation of EGF receptor. Multiple signaling pathways including Ras/mitogenic activated protein (MAP) kinase, protein kinase C (PKC) and phosphatidylinositol 3-kinase (PI3K) acted synergically in the cell response, whereas the activation of protein kinase A (PKA) pathway was found to antagonize the cell response.

Topics: beta-Cyclodextrins; Biosensing Techniques; Calcium; Carcinoma, Squamous Cell; Cell Adhesion; Cell Line, Tumor; Cholesterol; Cyclic AMP-Dependent Protein Kinases; Enzyme Activation; Enzyme-Linked Immunosorbent Assay; Epidermal Growth Factor; ErbB Receptors; Humans; Mitogen-Activated Protein Kinase 3; Optics and Photonics; Phosphatidylinositol 3-Kinases; Phosphorylation; Protein Kinase C; ras Proteins; Transcriptional Activation

Lipid rafts/caveolae are membrane platforms for signaling molecules that regulate various cellular functions, including cell survival. To better understand the role of rafts in tumor progression and therapeutics, we investigated the effect of raft disruption on cell viability and compared raft levels in human cancer cell lines versus their normal counterparts. Here, we report that cholesterol depletion using methyl-beta cyclodextrin caused anoikis-like apoptosis, which in A431 cells involved decreased raft levels, Bcl-xL down-regulation, caspase-3 activation, and Akt inactivation regardless of epidermal growth factor receptor activation. Cholesterol repletion replenished rafts on the cell surface and restored Akt activation and cell viability. Moreover, the breast cancer and the prostate cancer cell lines contained more lipid rafts and were more sensitive to cholesterol depletion-induced cell death than their normal counterparts. These results indicate that cancer cells contain increased levels of rafts and suggest a potential use of raft-modulating agents as anti-cancer drugs.

Topics: Apoptosis; bcl-X Protein; beta-Cyclodextrins; Breast Neoplasms; Carcinoma, Squamous Cell; Caspase 3; Caspases; Cell Line, Tumor; Cell Survival; Cholesterol; Down-Regulation; Enzyme Activation; ErbB Receptors; Female; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Male; Membrane Microdomains; Neoplasms; Prostatic Neoplasms; Proto-Oncogene Proteins c-akt; Signal Transduction; Simvastatin

Membranes and detergent-resistant membrane fractions isolated from human epidermoid carcinoma A431 cells after treatment with methyl-beta-cyclodextrin, a compound commonly used in pharmaceutical applications and in manipulation of membrane cholesterol content, display thermotropic transitions at about 15 degrees C and above 37 degrees C, respectively, when analyzed by differential scanning calorimetry. The transitions, absent in untreated cells, were reversible upon cycling through heating and cooling scans, and attributable to lipid components of the membranes, possibly sphingolipids. These results suggest that, after treatment with methyl-beta-cyclodextrin, membranes may show thermotropic transitions, an unusual feature for cellular bilayers, which is likely to influence biological functions.

Topics: beta-Cyclodextrins; Calorimetry, Differential Scanning; Carcinoma, Squamous Cell; Cell Fractionation; Cell Line, Tumor; Cell Membrane; Detergents; Humans; Membrane Lipids; Phase Transition; Temperature

The dissolution rate, the toxicity and the release from chewing gum of miconazole and econazole cyclodextrin products and complexes were investigated. The dissolution rate studies showed that an amorphous miconazole hydroxypropyl-beta-cyclodextrin product gave drug supersaturation, whereas drug supersaturation was not present during dissolution rate testing of an econazole hydroxypropyl-beta-cyclodextrin product. The miconazole hydroxypropyl-beta-cyclodextrin product and genuine cyclodextrin inclusion complexes of miconazole, econazole and clotrimazole were toxic on a human TR146 buccal cell culture model. The toxicity was probably due to drug supersaturation, thereby increasing the bioavailability of the antimycotics. The econazole hydroxypropyl-beta-cyclodextrin product and physical mixtures of miconazole or econazole and beta-cyclodextrin did not give supersaturation and were not as toxic as the above-mentioned compounds. Neat econazole and miconazole, a genuine econazole beta-cyclodextrin complex and the miconazole hydroxypropyl-beta-cyclodextrin product were incorporated in chewing gum. The miconazole hydroxypropyl-beta-cyclodextrin gum had a much higher drug release in vitro than the neat miconazole gum. The genuine econazole beta-cyclodextrin complex only increased the drug release moderately when compared with the release from the neat econazole gum. The release studies were performed on a mastication device.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; Antifungal Agents; beta-Cyclodextrins; Candida albicans; Carcinoma, Squamous Cell; Cheek; Chewing Gum; Cyclodextrins; Drug Delivery Systems; Econazole; Head and Neck Neoplasms; Humans; Kinetics; Miconazole; Microscopy, Electron, Scanning; Mouth Mucosa; Mouth Neoplasms; Solubility; Tumor Cells, Cultured