Search results for "Apoptosi"
showing 10 items of 1846 documents
Geldanamycin-induced osteosarcoma cell death is associated with hyperacetylation and loss of mitochondrial pool of heat shock protein 60 (hsp60)
2013
Osteosarcoma is one of the most malignant tumors of childhood and adolescence that is often resistant to standard chemo- and radio-therapy. Geldanamycin and geldanamycin analogs have been recently studied as potential anticancer agents for osteosarcoma treatment. Here, for the first time, we have presented novel anticancer mechanisms of geldanamycin biological activity. Moreover, we demonstrated an association between the effects of geldanamycin on the major heat shock proteins (HSPs) and the overall survival of highly metastatic human osteosarcoma 143B cells. We demonstrated that the treatment of 143B cells with geldanamycin caused a subsequent upregulation of cytoplasmic Hsp90 and Hsp70 w…
Mixed-ligand copper(ii)–sulfonamide complexes: effect of the sulfonamide derivative on DNA binding, DNA cleavage, genotoxicity and anticancer activity
2013
Four ternary complexes, [Cu(L1)2(bipy)] (1) [HL1 = N-(6-chlorobenzo[d]thiazol-2-yl)-4-methylbenzenesulfonamide], [Cu(L2)2(bipy)] (2) [HL2 = N-(benzo[d]thiazol-2-yl)-4-methylbenzenesulfonamide], [Cu(L3)2(bipy)]·1/2H2O (3) [HL3 = N-(5,6-dimethylbenzo[d]thiazol-2-yl)-4-methylbenzenesulfonamide] and [Cu(L4)2(bipy)] (4) [HL4 = N-(5,6-dimethylbenzo[d]thiazol-2-yl)benzenesulfonamide], were prepared and then characterized by X-ray crystallography, spectroscopy and magnetic measurements. Whereas the molecular structure of 1 and 2 consists of a discrete monomeric copper(II) species with a distorted square planar geometry, that of 3 and 4 consists of two independent molecules. In 3, both molecules pre…
Zinc overload mediated by zinc oxide nanoparticles as innovative anti-tumor agent
2017
The predicted global cancer burden is expected to surpass 20 million new cancer cases by 2025. Despite recent advancement in tumor therapy, a successful cancer treatment remains challenging. The emerging field of nanotechnology offers great opportunities for diagnosis, imaging, as well as treatment of cancer. Zinc oxide nanoparticles (ZnO NP) were shown to exert selective cytotoxicity against tumor cells via a yet unknown mechanism, most likely involving the generation of reactive oxygen species (ROS). These nanoparticles are a promising therapeutic opportunity as zinc is a nontoxic trace element and its application in medically-related products is considered to be safe. We could show that …
Anti-inflammatory effects of chemically modified tetracyclines by the inhibition of nitric oxide and interleukin-12 synthesis in J774 cell line
2001
We investigated the effects of chemically modified tetracyclines (CMTs) on the production of nitric oxide (NO) and on the synthesis of some cytokines: tumour necrosis factor alpha (TNF-alpha), interleukin(IL)-10 and IL-12 in lipopolysaccharide (LPS)-treated J774 cell line. Furthermore, we studied the ability of these drugs to modify the viability in LPS-stimulated J774 macrophages. CMTs decreased, in a dose-dependent manner, inducible NO synthase (iNOS) activity and, consequently, nitrite formation in J774 cultures. The CMT-induced decrease in NO production is due to the inhibition of enzyme activity rather than to a direct effect on enzyme expression. The absence of the inhibition in mRNA …
Characteristic ERK1/2 signaling dynamics distinguishes necroptosis from apoptosis
2021
International audience; ERK1/2 involvement in cell death remains unclear, although many studies have demonstrated the importance of ERK1/2 dynamics in determining cellular re- sponses. To untangle how ERK1/2 contributes to two cell death programs, we investigated ERK1/2 signaling dynamics during hFasL-induced apoptosis and TNF-induced necroptosis in L929 cells. We observed that ERK1/2 inhibition sensi- tizes cells to apoptosis while delaying necroptosis. By monitoring ERK1/2 activity by live-cell imaging using an improved ERK1/2 biosensor (EKAR4.0), we reported differential ERK1/2 signaling dynamics between cell survival, apoptosis, and nec- roptosis. We also decrypted a temporally shifted …
In vitro pro-apoptotic and anti-migratory effects of Treculia africana Decne. (Moraceae) and Entandrophragma angolense Welw (Meliaceae) extracts on p…
2021
Abstract Prostate cancer is the second leading cause of cancer deaths in men and there is an increasing interest in chemoprevention to fight it. The authors sought a scientific rationale for the traditional use of six Cameroonian medicinal plants for the treatment of prostate inflammation/tumour. The prostate cells viability incubated with each ethanolic plant extract was determined after 24, 48 and 72 h using the MTT assay. The antitumor mechanisms of promising extracts [Treculia africana (TA) and Entandrophragma angolense (EA)] were further assessed by evaluating cell growth, cell proliferation, cell cycle, cell death mechanisms and cell migration. Only TA and EA significantly inhibited L…
Synthesis and antiproliferative activity of substituted 3[2-(1H-indol-3-yl)-1,3-thiazol-4-yl]-1H-pyrrolo[3,2-b]pyridines, marine alkaloid nortopsenti…
2014
A large number of indolyl-4-azaindolyl thiazoles, nortopsentin analogues, were conveniently synthesized. The antiproliferative activity of the new derivatives was examined against four human tumor cell lines with different histologic origin. Seven derivatives consistently reduced the growth of the experimental models independently of TP53 gene status and exhibited the highest activity against the malignant peritoneal mesothelioma (STO) cell line. The most active compound of this series acts as a CDK1 inhibitor, and was found to cause cell cycle arrest at G 2 /M phase, to induce apoptosis by preventing the phosphorylation of survivin in Thr 34 and to increase the cytotoxic activity of paclit…
Cisplatin sensitivity is related to late DNA damage processing and checkpoint control rather than to the early DNA damage response
2008
The present study aimed at elucidating mechanisms dictating cell death triggered by cisplatin-induced DNA damage. We show that CL-V5B hamster mutant cells, a derivative of V79B, are hypersensitive to cisplatin-induced apoptotic death. CL-V5B cells are characterized by attenuated cisplatin-induced early (2-6 h) stress response, such as phosphorylation of stress-activated protein kinases (SAPK/JNK), ATM and Rad3-related (ATR) protein kinase, histone H2AX and checkpoint kinase-1 (Chk-1). Human FANCC cells also showed a reduced phosphorylation of H2AX and SAPK/JNK at early time point after cisplatin treatment. This was not the case for BRCA2-defective VC-8 hamster cells, indicating that the FA …
Cytotoxicity, anti-angiogenic, apoptotic effects and transcript profiling of a naturally occurring naphthyl butenone, guieranone A
2012
Abstract Background Malignant diseases are responsible of approximately 13% of all deaths each year in the world. Natural products represent a valuable source for the development of novel anticancer drugs. The present study was aimed at evaluating the cytotoxicity of a naphtyl butanone isolated from the leaves of Guiera senegalensis, guieranone A (GA). Results The results indicated that GA was active on 91.67% of the 12 tested cancer cell lines, the IC50 values below 4 μg/ml being recorded on 83.33% of them. In addition, the IC50 values obtained on human lymphoblastic leukemia CCRF-CEM (0.73 μg/ml) and its resistant subline CEM/ADR5000 (1.01 μg/ml) and on lung adenocarcinoma A549 (0.72 μg/m…
Cell cycle arrest and induction of apoptosis by cajanin stilbene acid from Cajanus cajan in breast cancer cells
2015
Abstract Background: The low abundant cajanin stilbene acid (CSA) from Pigeon Pea ( Cajanus cajan ) has been shown to kill estrogen receptor α positive cancer cells in vitro and in vivo . Downstream effects such as cell cycle and apoptosis-related mechanisms have not been analyzed yet. Material and methods: We analyzed the activity of CSA by means of flow cytometry (cell cycle distribution, mitochondrial membrane potential, MMP), confocal laser scanning microscopy (MMP), DNA fragmentation assay (apoptosis), Western blotting (Bax and Bcl-2 expression, caspase-3 activation) as well as mRNA microarray hybridization and Ingenuity pathway analysis. Results: CSA induced G2/M arrest and apoptosis …