Search results for "Neoplastic"
showing 10 items of 2901 documents
A review of natural and modified betulinic, ursolic and echinocystic acid derivatives as potential antitumor and anti-HIV agents.
2003
The aim of this review is to update current knowledge on the betulinic, ursolic and echinocystic acids and their natural and semisynthetic analogs, focussing on their cytotoxic and anti-HIV activities. Then, the last results of the authors' team on unusual semisynthetic derivatives of these triterpenoids will be presented in order to establish structure/activity relationships.
New ursolic and betulinic derivatives as potential cytotoxic agents.
2003
Fifteen new ursolic and betulinic triterpenoids, bearing various functionalities at C-3 and C-28 were synthesized as potential cytotoxic agents. All compounds were obtained by a hemisynthetic route via ursolic and betulinic acids. Preliminary screening of these compounds on human HT 29 colon cancer cells revealed inhibitory activity for three of them. Beta-D-Glucopyranosyl-3beta-hydroxyurs-12(13)-en-28-oate 1c, 3beta-3-(3-pyridyl)-prop-2-enoyloxyurs-12(13)-en-28-oic acid 1i and the potassium salt of 3beta-cinnamoyloxylup-20(29)-en-28-oic acid 2d demonstrated cytotoxic activity in the micromolar range: 8.0, 45.0 and 8.0 microM, respectively.
Aaptamine Derivatives from the Indonesian Sponge Aaptos suberitoides
2013
Four new aaptamine derivatives (1-4) along with aaptamine (5) and three related compounds (6-8) were isolated from the ethanol extract of the sponge Aaptos suberitoides collected in Indonesia. The structures of the new compounds were unambiguously determined by one- and two-dimensional NMR and by HRESIMS measurements. Compounds 3, 5, and 6 showed cytotoxic activity against the murine lymphoma L5178Y cell line, with IC(50) values ranging from 0.9 to 8.3 μM.
P-glycoprotein and its inhibition in tumors by phytochemicals derived from Chinese herbs
2011
P-glycoprotein belongs to the family of ATP-binding cassette (ABC) transporters. It functions in cellular detoxification, pumping a wide range of xenobiotic compounds, including anticancer drugs out of the cell. In cancerous cells, P-glycoprotein confers resistance to a broad spectrum of anticancer agents, a phenomenon termed multidrug resistance. An attractive strategy for overcoming multidrug resistance is to block the transport function of P-glycoprotein and thus increase intracellular concentrations of anticancer drugs to lethal levels. Efforts to identify P-glycoprotein inhibitors have led to numerous candidates, none of which have passed clinical trials with cancer patients due to the…
Occurrence of resveratrol and pterostilbene in age-old darakchasava, an ayurvedic medicine from India
2000
'Darakchasava' is a well known Indian herbal preparation of which the main ingredient is Vitis vinifera L. This 'ayurvedic' medicine is prescribed as a cardiotonic and also given for other disorders. HPLC analysis of this age old formulation revealed the presence of polyphenols like resveratrol and pterostilbene. These phenolic compounds are now known as antioxidants, cancer chemopreventive agents, and also known to reduce mortality from coronary heart disease by increasing high density lipoproteins like cholesterol and inhibiting platelet aggregation (Soleas, J.S., Diamandis, E.P., Goldberg, D.M., 1997. Resveratrol: a molecule whose time has come? and gone? Clin. Biochem. 30 (2), 91-113). …
Cytotoxicity of some Cameroonian spices and selected medicinal plant extracts
2011
Abstract Ethnopharmacological relevance Several medicinal plants and spices are used traditionally to treat cancers in Cameroon. Aim Methanol extracts from thirty-four spices and plants, with related ethnobotanical use were investigated for their in vitro cytotoxicity on the human pancreatic cancer cell line MiaPaCa-2, leukemia CCRF-CEM cells and their multidrug resistant (MDR) subline CEM/ADR5000, and the normal human umbilical vein endothelial cells (HUVECs). In addition the anti-angiogenic properties of the most active extracts were investigated. Material and methods The MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay was used for cyto…
Expression of the human complement C8 subunits is independently regulated by interleukin 1β, interleukin 6, and interferon γ
1998
The eighth component of human complement (C8) is composed of two subunits which are products from three separate genes. The alpha-gamma- and the beta-subunit of C8 are expressed independently, and are part of the membrane attack complex. C8 is primarily synthesized in the liver. It has been shown in previous studies that the human hepatoma cell line HepG2 constitutively expresses C8, and thus is a suitable model system for studying C8 biosynthesis in vitro. Expression is modulated by the cytokines IL-1 beta, IL-6 and IFN-gamma. The effect of the different cytokines on the expression of these subunits was examined using biosynthetical labelling and immunoprecipitation methods. C8 alpha-gamma…
Environmental and Product Contamination during the Preparation of Antineoplastic Drugs with Robotic Systems
2018
Abstract Background Robotic systems are designed to minimize the exposure to antineoplastic drugs during automated preparation. However, contamination cannot be completely excluded. The aim of the study was to evaluate the contamination with antineoplastic drugs on the working surfaces and on the outer surface of the ready-to-use products (infusion bags and syringes) during automated preparation with different versions of a robot and manual preparation. Methods Surface contamination with platinum (Pt) and 5-fluorouracil (5-FU) was measured by wipe sampling and quantified by voltammetry for Pt and GC-MS for 5-FU. Sampling was performed on pre-defined locations in the working areas before and…
Organic solvents vapor pressure and relative humidity effects on the phase transition rate of α and β forms of tegafur.
2011
The objective of this work was to investigate the relative humidity (RH) and solvent vapor pressure effects on the phase transition dynamics between tegafur polymorphic forms that do not form hydrates and solvates. The commercially available α and β modifications of 5-fluoro-1-(tetrahydro-2-furyl)-uracil, known as the antitumor agent tegafur, were used as model materials for this study. While investigating the phase transitions of α and β tegafur under various partial pressures of methanol, n-propanol, n-butanol, and water vapor, it was determined that the phase transition rate increased in the presence of solvent vapors, even though no solvates were formed. By increasing the relative air h…
Scelte terapeutiche e trattamento con sorafenib nell'epatocarcinoma: Analisi finale dello studio GIDEON in Italia
2015
Summary. Introduction. Sorafenib, an oral multikinase inhibitor, is the only targeted agent approved for the treatment of patients with hepatocellular carcinoma (HCC) after demonstration to increase overall survival compared to placebo in two randomized phase III study. GIDEON (Global Investigation of therapeutic DEcisions in HCC and Of its treatment with sorafeNib) is the largest, global, non-interventional, prospective study of patients with uHCC (n>3200) treated with sorafenib in real-life clinical practice conditions. Here we report the final analysis of safety and efficacy in the Italian cohort of patients. Methods. Patients with unresectable HCC who are candidates for systemic ther…