BackgroundLycopene, a major carotenoid component of tomato, has a potential anticancer activity in many types of cancer. Epidemiological and clinical trials rarely provide evidence for mechanisms of the compound’s action, and studies on its effect on cancer of different cell origins are now being done. The aim of the present study was to determine the effect of lycopene on cell cycle and cell viability in eight human cancer cell lines.MethodsHuman cell lines were treated with lycopene (1–5 μM) for 48 and 96 h. Cell viability was monitored using the method of MTT. The cell cycle was analyzed by flow cytometry, and apoptotic cells were identified by terminal deoxynucleotidyl transferase-mediated dUTP nick labeling (TUNEL) and by DAPI.ResultsOur data showed a significant decrease in the number of viable cells in three cancer cells lines (HT-29, T84 and MCF-7) after 48 h treatment with lycopene, and changes in the fraction of cells retained in different cell cycle phases. Lycopene promoted also cell cycle arrest followed by decreased cell viability in majority of cell lines after 96 h, as compared to controls. Furthermore, an increase in apoptosis was observed in four cell lines (T-84, HT-29, MCF-7 and DU145) when cells were treated with lycopene.ConclusionsOur findings show the capacity of lycopene to inhibit cell proliferation, arrest cell cycle in different phases and increase apoptosis, mainly in breast, colon and prostate lines after 96 h. These observations suggest that lycopene may alter cell cycle regulatory proteins depending on the type of cancer and the dose of lycopene administration. Taken together, these data indicated that the antiproliferative effect of lycopene was cellular type, time and dose-dependent.

Marine sponges (Porifera) display an ancestral type of cell-cell adhesion, based on carbohydrate-carbohydrate interaction. The aim of the present work was to investigate further details of this adhesion by using, as a model, the in vitro aggregation of dissociated sponge cells. Our results showed the participation of sulfated polysaccharides in this cell-cell interaction, as based on the following observations: (1) a variety of sponge cells contained similar sulfated polysaccharides as surface-associated molecules and as intracellular inclusions; (2) (35)S-sulfate metabolic labeling of dissociated sponge cells revealed that the majority (two thirds) of the total sulfated polysaccharide occurred as a cell-surface-associated molecule; (3) the aggregation process of dissociated sponge cells demanded the active de novo synthesis of sulfated polysaccharides, which ceased as cell aggregation reached a plateau; (4) the typical well-organized aggregates of sponge cells, known as primmorphs, contained three cell types showing sulfated polysaccharides on their cell surface; (5) collagen fibrils were also produced by the primmorphs in order to fill the extracellular spaces of their inner portion and the external layer surrounding their entire surface. Our data have thus clarified the relevance of sulfated polysaccharides in this system of in vitro sponge cell aggregation. The molecular basis of this system has practical relevance, since the culture of sponge cells is necessary for the production of molecules with biotechnological applications.

<p>O presente trabalho visa fazer um breve mapeamento cinema musical de ficção na América Latina, de modo a compreender como as diferentes cinematografias latinas se apropriaram do formato do musical e como este dialogou com as tradições culturais locais, em especial do cinema e da música popular, para se desenvolver. Buscaremos, pois, tratar de como o musical de ficção está ligado à história do cinema latino americano e das questões de identidade nacional e cultural que constantemente emergem das obras.</p>

Este artigo tem como objetivo identificar ‘pontos de contato’, interfaces entre os discursos acerca das comédias cinematográficas brasileiras que se tornaram conhecidas como chanchadas e os próprios filmes, em sua dimensão imanente, a partir da análise fílmica; em outras palavras, fazer encontrarem-se contexto e texto, discurso crítico e interpretação das obras. A primeira parte — metacrítica — revisita discursos acerca das chanchadas e observa uma mudança radical de polaridade na atribuição de valor a essa classe de filmes, que transita entre ser o mais desprezível e subserviente dos cinemas e ser um gênero subversivo, talvez o único que poderia ser considerado genuinamente brasileiro. O segundo momento — analítico —examina os filmes Nem Sansão nem Dalila e Matar ou correr, ambos dirigidos por Carlos Manga e lançados em 1954, com o intuito de procurar, nas obras, elementos que justifiquem a existência de duas visões tão opostas sobre um mesmo fenômeno. Percebendo a paródia como elemento fundamental da interface contexto-texto, tentamos também propor dois novos caminhos interpretativos para o estudo do gênero: um que trate os filmes a partir daquilo que têm de singular — o viés cômico — e outro que revela interessantes conexões entre as chanchadas e o cinema moderno brasileiro.