5 documents found, page 1 of 1
Analysis of EGFR Overexpression, EGFR gene amplification and the EGFRvIII Mutat...
Viana, Marta Pereira; Lopes, José M.; Little, Suzie; Milanezi, Fernanda; Basto, Diana; Pardal, Fernando; Jones, C.; Reis, R. M.Background: Patients with malignant gliomas do not respond to any current therapy. Epidermal growth factor receptor (EGFR) controls several oncogenic processes, being frequently up-regulated in gliomas due to overexpression, gene amplification and gene mutation. EGFR inhibitors are being tried in gliomas, yet the molecular determinants of therapeutic response are unclear. Materials and Methods: EGFR overexpress...
Quercetin enhances UVA-induced DNA damage in a rat fibroblast cell line
Castro, M. F.; Basto, Diana; Silva, João P.; Coutinho, O. P.Ultraviolet A (UVA) radiation from sunlight induces the production of reactive oxygen species (ROS), affecting a variety of cellular targets including the DNA. Quercetin, a flavonol present in many fruits, vegetables and beverages has been reported as a powerful antioxidant with an important role in prevention of carcinogenesis. The use of this compound, in topical formulations, could be of benefit in the preve...
Effects of two new di(hetero)arylamines on prevention of oxidative stress induc...
Basto, Diana; Silva, João P.; Queiroz, Maria João R. P.; Moreno, A. J.; Coutinho, O. P.We investigated the antioxidant properties of two new diarylamines from organic synthesis (MJQ1 and MJQ2), whose basic structure is similar to others, with reported antioxidant capacity, assessed by chemical tests, and biological activity against microorganisms. In this study we induced lipid peroxidation, in isolated rat liver mitochondria with ADP/Fe2+, and the diarylamine effects were examined by oxygen cons...
Mutation analysis of B-RAF gene in human gliomas
Basto, Diana; Trovisco, Vítor; Lopes, José M.; Martins, Albino; Pardal, Fernando; Soares, Paula; Reis, R. M.The RAS/RAF/MEK/ERK kinase pathway is pivotal in the transduction of mitogenic stimuli from activated growth factor receptors, which regulates cell proliferation, survival, and differentiation. Up-regulation of this pathway due to RAS mutations is found in approximately 30% of human tumors. Recently, activating mutations of B-RAF were identified in a large proportion of human cancers. Gliomas are the most frequ...
Molecular characterization of PDGFR-α/PDGF-A and c-KIT/SCF in gliosarcomas
Reis, R. M.; Martins, Albino; Ribeiro, Susana A.; Basto, Diana; Longatto Filho, Adhemar; Schmitt, Fernando C.; Lopes, José M.Gliosarcomas are rare and poorly characterized malignant brain tumors that exhibit a biphasic tissue pattern with areas of gliomatous and sarcomatous differentiation. These tumors are histological variants of glioblastoma, displaying a similar genetic profile and dismal prognosis. Up-regulation of PDGFR subfamily of tyrosine kinase members, PDGFR-α and c-Kit, and their intracellular effectors RAS/RAF/MAPK has a...