161 research outputs found

    Novel small molecule EGFR inhibitors as candidate drugs in non-small cell lung cancer.

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    In the last decade, better understanding of the role of epidermal growth factor receptor in the pathogenesis and progression of non-small cell lung cancer has led to a revolution in the work-up of these neoplasms. Tyrosine kinase inhibitors, such as erlotinib and gefitinib, have been approved for the treatment of non-small cell lung cancer, demonstrating an improvement in progression-free and overall survival, particularly in patients harboring activating EGFR mutations. Nevertheless, despite initial responses and long-lasting remissions, resistance to tyrosine kinase inhibitors invariably develops, most commonly due to the emergence of secondary T790M mutations or to the amplification of mesenchymal-epithelial transition factor (c-Met), which inevitably leads to treatment failure. Several clinical studies are ongoing (http://www.clinicaltrials.gov), aimed to evaluate the efficacy and toxicity of combined approaches and to develop novel irreversible or multitargeted tyrosine kinase inhibitors and mutant-selective inhibitors to overcome such resistance. This review is an overview of ongoing Phase I, II, and III trials of novel small molecule epidermal growth factor receptor inhibitors and combinations in non-small cell lung cancer patients

    In vitro anticancer activity and neurotoxicity of novel heavy metal-based anticancer complexes.

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    Cisplatin is one of the most effective metal-based anticancer agents, targeting a large number of solid tumours. Despite its efficacy, cisplatin treatment is still limited by severe side effects such as neuro-, hepato- and nephro-toxicity and by resistance phenomena, only partially overcome by the use of new platinum drugs (i.e. oxaliplatin and carboplatin). These problems have stimulated the research and development of alternative therapeutic strategies based on different heavy metals. In this work we investigated the in vitro activity and neurotoxicity of three anticancer complexes: [Cu(PTA)4]PF6, [Cu(thp)4]PF6 and [Au(PTA)4]PF6. Neurotoxicity was evaluated by embryonic rat dorsal root ganglia (DRG) organotypic culture model. Furthermore the extent of proteasome inhibition in rat embryonic DRG neurons was evaluated by fluorimetric assay. After 48 hours of treatment, both copper-based compounds were not neurotoxic even at higher concentrations with respect to the IC50 obtained in A549 and IGROV-1 human cancer cells while [Au(PTA)4]PF6 was neurotoxic at lower concentration than IC50 in cancer cell lines tested. Since the ubiquitin-proteasome system has been identified as molecular target in cancer cells for the heavy metal based-drug, we evaluated their ability to affect the proteasome machinery in DRG neurons. The copper-based compounds, that are not neurotoxic, do not inhibit proteasome activity in DRG neurons. On the contrary, the neurotoxic complex [Au(PTA)4] PF6, induces a significant inhibition of proteasome activity even at concentration lower than the IC50. Furthermore, based on the content in heavy metal-based atoms, the complexes used in this study are suitable candidates for Photon Activation Therapy (PAT). Pretreatment of IGROV-1 cells with [Cu(PTA)4]PF6 induces an increase cell death with respect to drug or synchrotron (SR) alone. Furthermore the SR/[Cu(PTA)4]PF6 combinational treatment induced an increase in DNA damage with respect to single treatments. Our results, together with the low IC50 of the copper compounds compared to the one observed for cisplatin, suggest them as promising compounds in anticancer treatment

    Temperature-dependent polymorphism of N-(4-fluorophenyl)-1,5-dimethyl-1H-imidazole-4-carboxamide 3-oxide: experimental and theoretical studies on intermolecular interactions in the crystal state

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    X-ray analysis of N-(4-fluorophenyl)-1,5-dimethyl-1H-imidazole-4-carboxamide 3-oxide reveals the temperature-dependent polymorphism associated with the crystallographic symmetry conversion. The observed crystal structure transformation corresponds to a symmetry reduction from I41 /a (I) to P43 (II) space groups. The phase transition mainly concerns the subtle but clearly noticeable reorganization of molecules in the crystal space, with the structure of individual molecules left almost unchanged. The Hirshfeld surface analysis shows that various intermolecular contacts play an important role in the crystal packing, revealing graphically the differences in spatial arrangements of the molecules in both polymorphs. The N-oxide oxygen atom acts as a formally negatively charged hydrogen bonding acceptor in intramolecular hydrogen bond of N–H…O− type. The combined crystallographic and theoretical DFT methods demonstrate that the observed intramolecular N-oxide N–H…O hydrogen bond should be classified as a very strong charge-assisted and closed-shell non-covalent interaction

    On the interaction between imidazoles and cadmium salts. Comparison between cadmium and zinc complexes of imidazoles

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    The reaction between benzimidazole (L 1), 4-phenylmidazole (L 2) or 2-phenylimidazole (L 3) and CdX 2 (X = Cl, Br, NO 3, ClO 4 or CH 3COO) has been investigated. 12 novel adducts have been obtained and characterized by analytical (elemental analysis and conductivity measurements) and spectral (IR, far IR, 1H and in some cases 113Cd NMR) data. The ligands L 1, L 2 and L 3 behave in the monodentate N-donor fashion, yielding 2:1 (L 2CdX 2; L = L 1, L 2 and L 3, X = Br and CH 3COO), 3:1 (L 3CdX 2; L = L 1, L 2 and L 3, X = Cl and ClO 4), 4:1 (L 4CdX 2; L = L 1 and L 3, X = ClO 4 and NO 3), 5:1 (L 5CdX 2; L = L 2, X = NO 3 and CH 3COO) and 3:2 (L 3[CdX 2] 2; L = L 3, Cl). The behavior of the adducts in acetone and chlorinated solvents is also discussed. Comparison is made with related Cd(II) and Zn(II) complexes of imidazoles
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