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Transforming Growth Factor-α and Epidermal Growth Factor
Published in Jason Kelley, Cytokines of the Lung, 2022
Of particular interest, TGF-α gene expression can be autoinduced by EGF or TGF-α. Exposure of cultured human keratinocytes to EGF or TGF-α enhances TGF-α message accumulation (Coffey et al., 1987). Similarly, EGF induces TGF-α mRNA accumulation in chemically transformed GP6ac cells (Raymond et al., 1989) and breast carcinoma cells MDA 468 (Bjorge et al., 1989). This EGF effect is inhibited by staurosporine, suggesting that EGF modulates TGF-α gene expression through a protein kinase C-mediated pathway. The significance of this autoinduction phenomenon is that TGF-α gene expression can be amplified by a positive autocrine feedback loop that utilizes the EGF receptor.
Pharmacological Management of Alzheimer’s Disease
Published in Sahab Uddin, Rashid Mamunur, Advances in Neuropharmacology, 2020
Rakesh Kumar, Rajan Kumar, Abhinav Anand, Neha Sharma, Navneet Khurana
Huperzine A is a reversible inhibitor of acetylcholinesterase and improves cognitive deficits of animal models in the AD. Huperzine A also has cell protection against Aβ protein, H2O2 and glutamate. It prevents cell against ischemia, staurosporine-induced cytotoxicity and apoptosis. Such protective effects protect mitochondria, regulate the expression of apoptotic proteins Bcl-2, Bax, P53, caspase-3, attenuates oxidative stress, and upregulates nerve growth factor. Huperzine A interferes with APP metabolism. It shows antagonizing effects for NMDA receptors and potassium currents that can also provide as neuroprotection (Wang et al., 2006).
CDK Inhibitors in Leukemia and Lymphoma
Published in Gertjan J. L. Kaspers, Bertrand Coiffier, Michael C. Heinrich, Elihu Estey, Innovative Leukemia and Lymphoma Therapy, 2019
UCN-01 (7-hydroxystaurosporine, NSC638850 or KW-2401; Kyowa Hakka Kogyo Company Ltd., Tokyo, Japan), a derivative of the nonspecific PKC inhibitor staurosporine (a natural product isolated from Streptomyces staurosporeus), was originally developed as a selective PKC inhibitor. Studies have also reported that UCN-01 inhibits several CDKs. However, recent studies have shown that it exerts other antitumor effects, including inhibition of Chk1, which results in “inappropriate” activation of CDKs and abrogation of DNA damage-induced cell cycle checkpoints, as well as interference with the PDKl/Akt survival pathway, thus promoting induction of apoptosis. These effects are largely independent of PKC inhibition. UCN-01 displays antitumor activity in in vitro systems and in vivo xenograft models involving multiple human tumor types, with greater antitumor effects observed in longer administration intervals (e.g., 72 hours in in vitro systems) (23).
Novel piperine-carboximidamide hybrids: design, synthesis, and antiproliferative activity via a multi-targeted inhibitory pathway
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2023
Lamya H. Al-Wahaibi, Mohamed A. Mahmoud, Yaser A. Mostafa, Ali E. Raslan, Bahaa G. M. Youssif
The MTT cytotoxicity assay was used to assess the anticancer activity of VIc, VIf, and VIk on the LOX-IMVI melanoma cell line, which comprises BRAFV600E kinase overexpression33. The compounds were evaluated at 5-dose concentrations to ascertain their IC50 values, with staurosporine acting as a control. Table 3 reveals that the derivatives VIc, VIf, and VIk have a high capacity to inhibit LOX-IMVI cell line survival, with IC50 values ranging from 1.05 µM to 1.40 µM. In all cases, the tested compounds were at least 5 times more effective than the reference Staurosporine, which had an IC50 of 7.10 µM. Compounds VIf and VIf demonstrated promising cytotoxic activity against LOX-IMVI melanoma cell line with IC50 values of 1.10 and 1.05 μM, respectively.
Thais savignyi tissue extract: bioactivity, chemical composition, and molecular docking
Published in Pharmaceutical Biology, 2022
Mohamed R. Habib, Ahmed A. Hamed, Rasha E. M. Ali, Khaled M. Zayed, Rasha M. Gad El-Karim, Rehab Sabour, Hanaa M. Abu El-Einin, Mosad A. Ghareeb
Cell lines for human kidney renal cell carcinoma UO-31, adenocarcinomic human alveolar basal epithelial cells A549 and human epidermoid carcinoma A431 were obtained from ATCC via the holding company for biological products and vaccines (VACSERA), Cairo, Egypt. Staurosporine was used as a positive control for comparison. The cell lines were freshly cultivated as monolayers in RPMI-1640 medium (Sigma Co., St. Louis, MO, USA), supplemented with 10% heat-inactivated fetal bovine serum (GIBCO, UK), 1% glutamine, 100 units/mL penicillin and 100 µg/mL streptomycin, and incubated at 37 °C in a 5% CO2 incubator. The cytotoxicity of the tested extract was evaluated using a colorimetric MTT assay. Cancer cell lines (1 4 cells/mL) were seeded in 96 flat-bottom well plates for screening. Different concentrations of Ts-EtOAc extract (0.4–100 µg/mL) were added to the cultures (in triplicates) and incubated for 24 h in 5% CO2 incubator. After 24 h, the cells were washed with PBS, mixed with 20 µL of MTT (Sigma Co., St. Louis, MO, USA) at a 5 mg/mL concentration, and subsequently incubated for 4 h at 37 °C in a 5% CO2 incubator. The purple formazan crystals formed were washed with 100 µL of DMSO, and each well’s optical density was observed. The colorimetric assay is measured and recorded at an absorbance of 570 nm using a plate reader (EXL 800, USA). The relative cell viability expressed as a percentage was calculated as follows:
Differential Cytotoxicity of Rooibos and Green Tea Extracts against Primary Rat Hepatocytes and Human Liver and Colon Cancer Cells – Causal Role of Major Flavonoids
Published in Nutrition and Cancer, 2021
Sedicka Samodien, Maryna de Kock, Elizabeth Joubert, Sonja Swanevelder, Wentzel C. A. Gelderblom
Hoechst 33342 nuclear staining was used to confirm the induction of apoptosis. HepG2, HT-29 and PH cells were seeded onto sterilized coverslips at a density of 25 × 104/mL in EMEM, DMEM and WE, respectively in 35 mm Petri dishes. Cells were treated with Rg, GRE and GT at concentrations representing their respective IC50 values for cell viability and proliferation. Of the pure flavonoids, luteolin and EGCG were used at their respective IC50 values for the inhibition of cell viability and cell proliferation. Incubations were conducted for 24 hrs using staurosporine (100 nM) as positive control. The media were discarded, Hoechst 33342 stain (1 µg/ml) added and cells further incubated at 37 °C for 30 min. The coverslip was removed, excess stain drained and mounted face down in anti-fade mounting medium (PBS/glycerol). Cells were analyzed under UV light using an Axio Vert Zeiss microscope (Zeiss, Germany) fitted with a blue filter (exclusion 358 nm, emission 461 nm) and photographs taken at x40 magnification.