Search results for "Cytotoxic"
showing 10 items of 1673 documents
Cytotoxicity of 4-hydroxy-N-(naphthalen-1-yl)-2-oxo-2H-chromene-3-carboxamide in multidrug-resistant cancer cells through activation of PERK/eIF2α/AT…
2021
After decades of research, multidrug resistance (MDR) remains a huge challenge in cancer treatment. In this study, the cytotoxic of 4-hydroxy-N-(naphthalen-1-yl)-2-oxo-2H-chromene-3-carboxamide (MCC1734) has been investigated towards multidrug-resistant cancer cell lines. MCC1734 exerted cytotoxicity on cell lines expressing different mechanisms of drug resistance (P-glycoprotein, BCRP, ABCB5, EGFR, p53 knockout) to a different extent. Interestingly, sensitive CCRF-CEM cells and multidrug-resistant P-gp-overexpressing CEM/ADR5000 cells represented similar sensitivity towards MCC1734, indicating MCC1734 can bypass P-gp-mediated resistance. Microarray-based mRNA expression revealed that MCC17…
NKG2D induces Mcl-1 expression and mediates survival of CD8 memory T cell precursors via phosphatidylinositol 3-kinase.
2013
Abstract Memory formation of activated CD8 T cells is the result of a specific combination of signals that promote long-term survival and inhibit differentiation into effector cells. Much is known about initial cues that drive memory formation, but it is poorly understood which signals are essential during the intermediate stages before terminal differentiation. NKG2D is an activating coreceptor on Ag-experienced CD8 T cells that promotes effector cell functions. Its role in memory formation is currently unknown. In this study, we show that NKG2D controls formation of CD8 memory T cells by promoting survival of precursor cells. We demonstrate that NKG2D enhances IL-15–mediated PI3K signalin…
Interactions between T-2 toxin and its metabolites in HepG2 cells and in silico approach
2021
Abstract The T-2 toxin (T-2) is commonly metabolized to HT-2 toxin (HT-2), Neosolaniol (NEO), T2-triol and T2-tetraol and they can modify the toxicity of T-2. In this study, T-2 and its modified forms were evaluated by in vitro and in silico methods. The in vitro cytotoxicity individually was evaluated by MTT and Total Protein Content (PC) assays in human hepatocarcinoma (HepG2) cells. The order of IC50 was T-2 tetraol > T-2 triol > NEO > T-2 = HT-2. The T-2 and HT-2 evidenced the highest cytotoxic effect in HepG2 cells individually. No differences were observed in binary combinations tested and the two mycotoxins in the mixture tested individually. The T-2+HT-2 combination showed the highe…
Saponins-mediated potentiation of cisplatin accumulation and cytotoxicity in human colon cancer cells.
2002
The triterpene saponins jenisseensosides A, B, C, D were found to increase the accumulation and cytotoxicity of the anticancer agent cisplatin in human colon tumor cells. These compounds are glycosides of quillaic acid whose fucose residue was acylated by a trans- or cis-p methoxycinnamic acid. In contrarst, other saponins derivatives without this acyl moiety were not found to potentiate the accumulation and cytotoxicity of cisplatin. These results suggested the importance of the acyl moiety for activity.
Synthesis and biological evaluation of a D-ring-contracted analogue of lamellarin D
2017
A D-ring contracted analogue of the strongly cytotoxic marine pyrrole alkaloid lamellarin D was synthesized and investigated for its antiproliferative action towards a wild type and a multidrug resistant (MDR) cancer cell line. The compound was found to inhibit tumor cell growth at submicromolar concentrations and showed a lower relative resistance in the MDR cell line than the antitumor drug camptothecin to which lamellarin D shows cross resistance and with which lamellarin D shares the same binding site.
Cyclic heptapeptides from the soil-derived fungus Clonostachys rosea
2019
Abstract Three new cyclic heptapeptides (1–3) together with three known compounds (4–6) were isolated from a solid rice culture of the soil-derived fungus Clonostachys rosea. Fermentation of the fungus on white beans instead of rice afforded a new γ-lactam (7) and a known γ-lactone (8) that were not detected in the former extracts. The structures of the new compounds were elucidated on the basis of 1D and 2D NMR spectra as well as by HRESIMS data. Compounds 1 and 4 exhibited significant cytotoxicity against the L5178Y mouse lymphoma cell line with IC50 values of 4.1 and 0.1 µM, respectively. Compound 4 also displayed cytotoxicity against the A2780 human ovarian cancer cell line with an IC50…
Toxicity evaluation of individual and mixed enniatins using an in vitro method with CHO-K1 cells
2013
Enniatins (ENs) A, A1, B and B1 are produced by Fusarium species. They are known as emerging fusario- toxins, and can cause outbreaks in both humans and animals. ENs elicits a wide range of different biolog- ical properties and toxicological effects, and their co-occurrence may enhance the extent of these hazards. As the potential toxins reach in vitro cells in the same way as they would in vivo, cytotoxicity was studied with CHO-K1, which is considered one of the most sensitive cell lines for preliminary screen- ing of cytotoxicity studies. In this study, individual cytotoxic effects of ENs were evaluated by MTT assay after exposing ENs to CHO-K1 cells for 24, 48, and 72 h. The IC50 values…
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 …
In vitro effects of aminobisphosphonates on Vgamma9Vdelta2 T cell activation and differentiation.
2006
In this study we have evaluated the in vitro effects of four different aminobisphosphonates, alendronate, risedronate, neridronate and zoledronate, on Vγ9Vδ2 T cell activation and differentiation. All tested aminobisphosphonates induce an IL-2-dependent activation and expansion of Vγ9Vδ2 T lymphocytes in primary PBMC cultures of healthy donors. Most notably, they also determine a different distribution of Vγ9Vδ2 T cell subsets, with decrease of Tnaive and TCM cells and increase of TEM and TEMRA Vγ9Vδ2 cells, indicating that in vitro treatment with aminobisphosphonates induces Vγ9Vδ2 T lymphocytes to differentiate towards an effector/cytotoxic phenotype. Accordingly, Vγ9Vδ2 T lymphocytes cu…
Cladribine exerts an immunomodulatory effect on human and murine dendritic cells
2014
Cladribine is a purine nucleoside analog developed to treat lymphoid malignancies. Reported therapeutic benefits for the autoimmune disease multiple sclerosis indicate additional immunomodulatory effects beyond the well-characterized cytotoxic activity causing lymphopenia. Here, we demonstrate that cladribine reduces the secretion of inflammatory cytokines and chemokines by murine and human dendritic cells, the most potent antigen-presenting cells. This compound also modulates the expression of the activation markers CD86 and MHC II. Furthermore, cladribine affects the T cell priming capacity of dendritic cells, resulting in reduced induction of interferon-γ- and tumor necrosis factor-α-pro…