Anomalous Features of EMT during Keratinocyte Transformation

During the evolution of epithelial cancers, cells often lose their characteristic features and acquire a mesenchymal phenotype, in a process known as epithelial-mesenchymal transition (EMT). In the present study we followed early stages of keratinocyte transformation by HPV16, and observed diverse cellular changes, associated with EMT. We compared primary keratinocytes with early and late passages of HF1 cells, a cell line of HPV16-transformed keratinocytes. We have previously shown that during the progression from the normal cells to early HF1 cells, immortalization is acquired, while in the progression to late HF1, cells become anchorage independent. We show here that during the transition from the normal state to late HF1 cells, there is a progressive reduction in cytokeratin expression, desmosome formation, adherens junctions and focal adhesions, ultimately leading to poorly adhesive phenotype, which is associated with anchorage-independence. Surprisingly, unlike “conventional EMT”, these changes are associated with reduced Rac1-dependent cell migration. We monitored reduced Rac1-dependent migration also in the cervical cancer cell line SiHa. Therefore we can conclude that up to the stage of tumor formation migratory activity is eliminated

The desmosome and pemphigus

Desmosomes are patch-like intercellular adhering junctions (“maculae adherentes”), which, in concert with the related adherens junctions, provide the mechanical strength to intercellular adhesion. Therefore, it is not surprising that desmosomes are abundant in tissues subjected to significant mechanical stress such as stratified epithelia and myocardium. Desmosomal adhesion is based on the Ca2+-dependent, homo- and heterophilic transinteraction of cadherin-type adhesion molecules. Desmosomal cadherins are anchored to the intermediate filament cytoskeleton by adaptor proteins of the armadillo and plakin families. Desmosomes are dynamic structures subjected to regulation and are therefore targets of signalling pathways, which control their molecular composition and adhesive properties. Moreover, evidence is emerging that desmosomal components themselves take part in outside-in signalling under physiologic and pathologic conditions. Disturbed desmosomal adhesion contributes to the pathogenesis of a number of diseases such as pemphigus, which is caused by autoantibodies against desmosomal cadherins. Beside pemphigus, desmosome-associated diseases are caused by other mechanisms such as genetic defects or bacterial toxins. Because most of these diseases affect the skin, desmosomes are interesting not only for cell biologists who are inspired by their complex structure and molecular composition, but also for clinical physicians who are confronted with patients suffering from severe blistering skin diseases such as pemphigus. To develop disease-specific therapeutic approaches, more insights into the molecular composition and regulation of desmosomes are required

Effect of polyphenols dietary grape by-products on chicken patties

An experiment was conducted to study the dietary effect that the inclusion (40 g kg) of grape seed (GS), grape skin (SS), grape pomace (GP), and (0.2 g kg) of vitamin E (E) had on the composition and microbiological quality of chicken breast meat and on the physico-chemical parameters (TBARS, pH, color, Kramer shear force), sensorial characteristics, and microbiological quality of chicken breast meat patties during chilled storage (0, 3, 6, and 9 days) at 2 °C. In general, proximate composition and microbial counts of the raw chicken breast meat and the patties were not affected. Lower TBARS values were detected in patties formulated with breast meat obtained from birds fed E, SS, and GP diets. No clear effect was observed on the color or textural characteristics of the different patties. The addition of SS and GP in chicken diets reduced TBARS values showing some improvement in the oxidative stability of breast patties without affecting its technological properties, sensorial attributes, or microbial quality.The authors thank the MINECO and CSIC for financial support of Projects AGL2012-31355/GAN, AGL2014-53207-C2-1-R, and the Intramural 2014470E073. In addition, we are grateful to CAM and ESI Funds for financially supporting project MEDGAN-CM S2013/ABI2913). We would also like to thank MIUR and UNIMOL for the Ph.D. fellowship of Maria Nardoia.Peer Reviewe