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Since the activity of several conventional anticancer drugs is restricted by resistance mechanisms and dose-limiting side-effects, the design of formulations for local application on malignant lesions seems to be an efficient and promising drug delivery approach. In this study, the effect of locally applied 5-FU on cell death was evaluated both in a SCC4/HEK001 model and in a newly proposed 3D outgrowth model of oral squamous cell carcinoma (OSCC). Initially, the optimal drug dose was established by delivery of solutions containing different amounts of 5-FU. The solution containing 1% (w/v) of 5-FU resulted effective in inducing cell death with complete eradication of cell colonies. Buccal tablets were designed to deliver 5-FU locoregionally to the cancer lesions of the oral cavity. Tablets were prepared using a drug loaded matrix of acrylic/methacrylic acid copolymer containing 1% (w/w) of 5-FU and applied on 3D outgrowths. The drug release from tablets appeared to be sufficient to induce cell death as confirmed by transmission electron microscopy and enzymatic assay (TUNEL). After 120 h of treatment, when about 90% of the drug had been discharged from the tablets into the culture environment, 5-FU caused loss of cell-cell communications and apoptotic cell death. After 192 h, a complete disaggregation of the 3D oral outgrowths and the death of all the cells was observed. Buccal matrix tablets could be considered a promising new approach to the locoregional treatment of OSCC. Risks of systemic toxicity are avoided since very low drug doses are delivered.

Recently it has been hypothesized that a reactivation of the epithelial-mesenchymal trophic unit (EMTU) of the respiratory mucosa, caused by extensive epithelial damage, may be responsible for the pathogenesis of asthma. However, most research on this subject so far has been limited by the unavailability of in vitro models correctly mimicking the three-dimensional architecture of the properly differentiated human bronchial mucosa. For this reason, we have developed a novel 3D outgrowth model, obtained from bronchial biopsies and composed of both human bronchial epithelial cells (goblet and columnar cells) and fibroblasts with their basement membrane. Here we present the preliminary data obtained by both SEM and TEM on the characterization of these bronchial outgrowths showing that cells and matrices within the 3D structures are well differentiated, presenting all the normal features of human bronchial mucosa such as microvilli, cilia, mucus, tight junctions, collagens etc. We also show the effects of medium-term treatment with cigarette smoke extracts in terms of cell survival and remodeling.

The link between cigarette smoke (CS) and lung inflammation is quite strong, however relatively little is still known on the effects of CS on human bronchial epithelial cells survival during asthma. In this study we focused our attention on the apoptotic effects of CS on healthy (HC) and asthmatic (AS) primary bronchial epithelial cells (PBEC) and on the role of antioxidants to protect epithelial cells from CSE-induced apoptosis. Twenty subjects (10 HC and 10 AS) were recruited for this study and PBEC were obtained by bronchoscopy. PBEC were treated with oxidants (H2O), anti-oxidants (GSH and AA) and cigarette smoke extracts (CSE). Early apoptosis (EA) and necrosis were measured by flow cytometry using Annexin-V and propidium iodide. After treatment with CSE 20%, AS showed an increased susceptibility to the CSE treatment compared to HC (24.34+/-9.61 vs 48.45+/-11.91, p=0.003). Similarly, when EA was taken into consideration, there was a significant increase of EA cells in the AS group treated with CSE compared to HC (33.12+/-10.38 vs 16.73+/-6.92, p

Background: The β 2 -adrenoceptor polymorphisms occurring at amino acid positions 16 (arginine to glycine) and 27 (glutamine to glutamate) are known to be functionally relevant and also disease-modifying in subjects with asthma. However, the contribution of these polymorphisms to the development of the asthmatic phenotype or other markers for allergic disease remains to be established. Objective: This large family study examines the contributions of these polymorphisms in determining the heritable component of markers for allergic disease in asthmatic families. Methods: Three hundred twenty-four individuals from 60 families multiplex for asthma selected by means of an asthmatic proband were characterized for the following markers of allergic disease: asthma, atopy, and serum IgE. The polymerase chain reaction was used to generate a 234 base pair fragment spanning the region of interest, and the β 2 -adrenoceptor polymorphism was then defined by allele-specific oligonucleotide hybridization. Segregation analysis was then performed. Results: We found a significant association ( p = 0.009) between the glutamine 27 β 2 -adrenoceptor polymorphism and elevated levels of IgE, which was supported by the observation of linkage between IgE and β 2 -adrenoceptor polymorphisms at locus 27 ( p = 0.037). However, there was no association between either the arginine-glycine 16 or the glutamine-glutamate 27 β 2 -adrenoceptor polymorphism and an increased risk of asthma or atopy per se. Conclusion: The glutamine 27 β 2 -adrenoceptor polymorphism appears to contribute to IgE variability in families with asthma. However, it seems that although both amino acid 16 and 27 β 2 -adrenoceptor polymorphisms are disease-modifying in subjects with asthma, they do not contribute markedly to the development of the asthmatic phenotype. (J Allergy Clin Immunol 1997;100:261-5.)

With advances in molecular biology, the complex inflammatory events that underlie asthma are being unraveled. The players are diverse, involving two populations each of mast cells and helper T cells, eosinophils, bronchial endothelial and epithelial cells, and an array of vasoactive and bronchoactive mediators. The clinical message is already clear: Treat the inflammation early.

A major part of the burden of asthma is caused by acute exacerbations. Exacerbations have been strongly and consistently associated with respiratory infections. Respiratory viruses and bacteria are therefore possible treatment targets. To have a reasonable estimate of the burden of disease induced by such infectious agents on asthmatic patients, it is necessary to understand their nature and be able to identify them in clinical samples by employing accurate and sensitive methodologies. This systematic review summarizes current knowledge and developments in infection epidemiology of acute asthma in children and adults, describing the known impact for each individual agent and highlighting knowledge gaps. Among infectious agents, human rhinoviruses are the most prevalent in regard to asthma exacerbations. The newly identified type-C rhinoviruses may prove to be particularly relevant. Respiratory syncytial virus and metapneumovirus are important in infants, while influenza viruses seem to induce severe exacerbations mostly in adults. Other agents are relatively less or not clearly associated. Mycoplasma and Chlamydophila pneumoniae seem to be involved more with asthma persistence rather than with disease exacerbations. Recent data suggest that common bacteria may also be involved, but this should be confirmed. Although current information is considerable, improvements in detection methodologies, as well as the wide variation in respect to location, time and populations, underline the need for additional studies that should also take into account interacting factors.

Rhinoviruses are the major cause of common colds and of asthma exacerbations. Intercellular adhesion molecule-1 (ICAM-1) has a central role in airway inflammation and is the receptor for 90% of rhinoviruses. Rhinovirus infection of airway epithelium induces ICAM-1. Because redox state is directly implicated in inflammatory responses via molecular signaling mechanisms, here we studied the effects of reducing agents on rhinovirus-induced ICAM-1 expression, mRNA upregulation, promoter activation, and nuclear factor activation. To investigate the effects of rhinovirus infection on the intracellular redox balance, we also studied whether rhinovirus infection triggers the production of reactive oxygen species. We found that reduced (GSH) but not oxidized (GSSG) glutathione (1-100 muM) inhibited in a dose-dependent manner rhinovirus-induced ICAM-1 up-regulation and mRNA induction in primary bronchial and A549 respiratory epithelial cells. GSH but not GSSG also inhibited rhinovirus-induced ICAM-1 promoter activation and rhinovirus-induced NF-kappaB activation. In parallel, we found that rhinovirus infection induced a rapid increase of intracellular superoxide anion that was maximal at the time of NF-kappaB activation. This oxidant generation was completely inhibited by GSH. We conclude that redox-mediated intracellular pathways represent an important target for the therapeutic control of rhinovirus-induced diseases.