Search results for "breast cancer cells"
showing 10 items of 38 documents
The oxygen radicals involved in the toxicity induced by parthenolide in MDA-MB-231 cells
2014
It has been shown that the sesquiterpene lactone parthenolide lowers the viability of MDA-MB-231 breast cancer cells, in correlation with oxidative stress. The present report examined the different radical species produced during parthenolide treatment and their possible role in the toxicity caused by the drug. Time course experiments showed that in the first phase of treatment (0-8 h), and in particular in the first 3 h, parthenolide induced dichlorofluorescein (DCF) signal in a large percentage of cells, while dihydroethidium (DHE) signal was not stimulated. Since the effect on DCF signal was suppressed by apocynin and diphenyleneiodonium (DPI), two inhibitors of NADPH oxidase (NOX), we s…
Antitumor effects of curcumin and structurally β-diketone modified analogs on multidrug resistant cancer cells
2007
Abstract Using concepts of bioisostery a series of curcumin analogs were synthesized: the diketonic system of the compound was elaborated into enaminones, oximes, and the isoxazole heterocycle. The cell growth inhibitory and apoptosis inducing effects of the new analogs were evaluated by in vitro assays in the hepatocellular carcinoma HA22T/VGH cells, as well as in the MCF-7 breast cancer cell line and in its multidrug resistant (MDR) variant MCF-7R. Increased antitumor activity on all cell lines was found with the isoxazole analog and especially with the benzyl oxime derivative; in the HA22T/VGH cell model, the latter compound inhibited constitutive NF-κB activation.
FT-IR spectroscopy studies of the breast cancer cell composition changes induced by Au-BSA nanoclusters
2016
Midregion PTHrP and Human Breast Cancer Cells
2010
PTHrP is a polyhormone undergoing proteolytic processing into smaller bioactive forms, comprising an N-terminal peptide, which is the mediator of the “classical” PTH-like effect, as well as midregion and C-terminal peptides. The midregion PTHrP domain (38-94)-amide was found to restrain growth and invasionin vitroof some breast cancer cell lines, causing striking toxicity and accelerating death; the most responsive being MDA-MB231, whose tumorigenesis was also attenuatedin vivo. In addition, midregion PTHrP appears to be imported in the nucleoplasm of cultured MDA-MB231 cells andin vitro, it can bind chromatin of metaphase spread preparations and also an isolated 20-mer oligonucleotide, the…
Multiple effects induced by herceptin® on 8701-BC breast cancer cells
2008
Herceptin, an anti-neoplastic humanized monoclonal antibody (Herceptin®, Roche, CH), has been shown to be active against breast cancer cells over-expressing HER-2 receptor. HER-2 is a cell membrane protein that belongs to the epidermal growth factor receptors family and that results over-expressed in the 25-30% of breast cancer patients. The over-expression of HER-2 is considered a predictive and prognostic marker for breast cancer malignancy and invasiveness. On these bases, we aimed to analyze the effects caused by Herceptin treatment on 8701-BC breast cancer cells (Minafra et al., 1989). Firstly we evaluated the effects of Herceptin on the growth rate of 8701-BC cells. To this purpose, p…
Herceptin Resistance and Malignant Potential of Cancer Cells.
2009
The HDAC inhibitor SAHA synergistically stimulates the cytotoxic effect induced by Parthenolide in MDA-MB231 cells
2014
We showed that the sesquiterpene lactone Parthenolide (PN) exerts strong cytotoxic effects on triple negative breast cancer MDA-MB231 cells. Our recent results suggest that PN exerts in these cells a cytoprotective effect, which is due to the activation of mTOR pathway. To inhibit this protective response we employ the HDAC inhibitor SAHA, which is known to prevent AKT/mTOR pathway. We show that PN activates Akt, mTOR, p70S6kinase and NRF2 while SAHA abolishes these effects. Further cell pretreatment with SAHA synergistically sensitizes the cells to the cytotoxic effect of PN. Moreover SAHA alone activates the autophagic process. The addition of PN to SAHA reduces this effect and induces ap…
Cytotoxic Bufadienolides from the Leaves of Melianthus major
2020
Melianthus major is a medicinal plant endemic to South Africa. Its leaf extract led to the isolation of five new bufadienolides, 2β-acetoxy-3,5-di-O-acetylhellebrigenin (1), 2β-acetoxy-3-O-acetylhellebrigenin (2), 2β-acetoxy-14-deoxy-15β,16β-epoxymelianthugenin (4), 2β-acetoxy-14-deoxy-15β,16β-epoxymelianthusigenin (5), and 2β-hydroxymelianthusigenin (6), and four known analogues. The structures of the compounds were elucidated using NMR and HRESIMS data analyses. The relative configurations were defined by single-crystal X-ray crystallography and NOESY correlations. The isolated compounds exhibited strong cytotoxicity against MCF-7 breast cancer cells and sensitive CCRF-CEM and multidrug-r…
SPIONs embedded in polyamino acid nanogels to synergistically treat tumor microenvironment and breast cancer cells.
2018
Abstract The extremely complex tumor microenvironment (TME) in humans is the major responsible for the therapeutic failure in cancer nanomedicine. A new concept of disease-driven nanomedicine, henceforth named “Theranomics”, which attempts to target cancer cells and TME on the whole, represents an attractive alternative. Herein, a nanomedicine able to co-deliver doxorubicin and a tumor suppressive proteolytic protein such as collagenase-2 was developed. We successfully obtained superparamagnetic nanogels (SPIONs/Doco@Col) via the intermolecular azide-alkyne Huisgen cycloaddition. We demonstrated that a local ECM degradation and remodeling in solid tumors by means of collagenase-2 could enha…