Sea anemones produce ion channels peptide toxins of pharmacological and biomedical interest. However, peptides acting on ligand-gated ion channels, including acid-sensing ion channel (ASIC) toxins, remain poorly explored. PhcrTx1 is the first compound characterized from the sea anemone Phymanthus crucifer, and it constitutes a novel ASIC inhibitor.
View Article and Find Full Text PDFTamoxifen is the most frequently used drug for hormone therapy of breast cancer patients, even though a high percentage of women are (or become) refractory to this treatment. The proteins involved in tamoxifen resistance of breast tumor cells as well as the mechanisms by which they interact, are still unknown. Some years ago, we established the xenograft breast tumor 3366, sensitive to tamoxifen and the 3366/TAM, resistant to tamoxifen, derived after two years of in vivo passages of the parental 3366 under tamoxifen treatment.
View Article and Find Full Text PDFAn efficient method for digestion and extraction of proteolytic peptides from silver-stained proteins was applied to the characterization of nuclear proteins from the small cell lung cancer H82 (ATCC HTB 175) cell line previously separated by high-resolution large format two-dimensional gel electrophoresis. From 68 spots, evenly distributed on the gel area and representing a wide range of spot intensities, 63 (92%) were successfully identified by matrix-assisted laser desorption/ionization (MALDI) or electrospray ionozation-mass spectrometry (ESI-MS). In five cases where the identification was not possible, the presence of an intense background apparently due to the leakage of polymers from the microtubes or other plastics, was detected.
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