Ascorbate potentiates the cytotoxicity of menadione leading to an oxidative stress that kills cancer cells by a non-apoptotic caspase-3 independent form of cell death

311 Background: Both oxidative stress and inflammation play important roles in prostate cancer cell apoptosis or proliferation. However, the mechanisms underlying these processes remain unclear. Thus, we chose IL-8 as the bridge between inflammation and cancer cell oxidative stress-induced death and confirmed its connection with mTOR and GSK-3beta. Methods: We overexpressed GSK-3beta and observed the effect of GSK-3beta on reactive oxygen species (ROS) and cell death induced by oxidative stress. Then, IL-8 was upregulated or downregulated to determine its impact on preventing cells from damage by GSK-3beta-induced oxidative stress. In addition, we confirmed the role of mTOR in this process through its overexpression or knockdown. Real-time PCR, Western blotting, transcription, Cell Counting Kit 8, flow cytometry and other techniques were used. Results: IL-8 promotes prostate cancer cell proliferation and decreases apoptosis, while GSK-3beta induces cell death by oxidative stress through the activation of the caspase-3 signaling pathway by increasing ROS. In addition, mTOR can also decrease the activation of the caspase-3 signaling pathway by inhibiting GSK--3beta and thus decreasing ROS production. Moreover, the inhibitory effect of IL-8 on GSK-3beta occurs through the regulation of mTOR. Conclusions: The results of this study highlight the importance of GSK-3beta, which increases the production of ROS and then induces oxidative stress in tumor cells, while IL-8 and mTOR attenuate the oxidative stress to protect prostate cancer cells through the inhibitor GSK-3beta.

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Oxidative Stress and Apoptotic Responses Elicited by Nostoc-Synthesized Silver Nanoparticles against Different Cancer Cell Lines

Cancers ◽

10.3390/cancers12082099 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2099 ◽

Cited By ~ 3

Author(s):

Reham Samir Hamida ◽

Gadah Albasher ◽

Mashael Mohammed Bin-Meferij

Keyword(s):

Oxidative Stress ◽

Silver Nanoparticles ◽

Cancer Cells ◽

Hepg2 Cells ◽

Caspase 3 ◽

Mammalian Target Of Rapamycin ◽

B Cell Lymphoma ◽

Phosphorylated Akt ◽

Hct 116 ◽

Mcf 7

Green nanoparticles represent a revolution in bionanotechnology, providing opportunities to fight life-threatening diseases, such as cancer, with less risk to the environment and to human health. Here, for the first time, we systematically investigated the anticancer activity and possible mechanism of novel silver nanoparticles (N-SNPs) synthesized by Nostoc Bahar M against the MCF-7 breast cancer cells, HCT-116 colorectal adenocarcinoma cells, and HepG2 liver cancer cells, using cell viability assays, morphological characterization with inverted light and transmission electron microscopy, antioxidants and enzymes (glutathione peroxidase (GPx), glutathione (GSH), adenosine triphosphatase (ATPase), and lactate dehydrogenase (LDH)), and western blotting (protein kinase B (Akt), phosphorylated-Akt (p-Akt), mammalian target of rapamycin (mTOR), B-cell lymphoma 2 (Bcl-2), tumor suppressor (p53), and caspase 3). N-SNPs decreased the viability of MCF-7, HCT-116, and HepG2 cells, with half-maximal inhibitory concentrations of 54, 56, and 80 µg/mL, respectively. They also significantly increased LDH leakage, enhanced oxidative stress via effects on antioxidative markers, and caused metabolic stress by significantly decreasing ATPase levels. N-SNPs caused extensive ultrastructural alterations in cell and nuclear structures, as well as in various organelles. Furthermore, N-SNPs triggered apoptosis via the activation of caspase 3 and p53, and suppressed the mTOR signaling pathway via downregulating apoptosis-evading proteins in MCF-7, HCT-116, and HepG2 cells. Ultrastructural analysis, together with biochemical and molecular analyses, revealed that N-SNPs enhanced apoptosis via the induction of oxidative stress and/or through direct interactions with cellular structures in all tested cells. The cytotoxicity of Nostoc-mediated SNPs represents a new strategy for cancer treatment via targeting various cell death pathways. However, the potential of N-SNPs to be usable and biocompatible anticancer drug will depend on their toxicity against normal cells.

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Interplay between Endoplasmic Reticular Stress and Survivin in Colonic Epithelial Cells

Cells ◽

10.3390/cells7100171 ◽

2018 ◽

Vol 7 (10) ◽

pp. 171 ◽

Cited By ~ 8

Author(s):

Rohit Gundamaraju ◽

Ravichandra Vemuri ◽

Wai Chin Chong ◽

Stephen Myers ◽

Shaghayegh Norouzi ◽

...

Keyword(s):

Cell Death ◽

Cancer Cells ◽

Inflammatory Markers ◽

Caspase 3 ◽

Annexin V ◽

Parp Cleavage ◽

Cellular Survival ◽

Unfolded Protein ◽

Proliferative Assay ◽

The Unfolded Protein Response

Sustained endoplasmic reticular stress (ERS) is implicated in aggressive metastasis of cancer cells and increased tumor cell proliferation. Cancer cells activate the unfolded protein response (UPR), which aids in cellular survival and adaptation to harsh conditions. Inhibition of apoptosis, in contrast, is a mechanism adopted by cancer cells with the help of the inhibitor of an apoptosis (IAP) class of proteins such as Survivin to evade cell death and gain a proliferative advantage. In this study, we aimed to reveal the interrelation between ERS and Survivin. We initially verified the expression of Survivin in Winnie (a mouse model of chronic ERS) colon tissues by using immunohistochemistry (IHC) and immunofluorescence (IF) in comparison with wild type Blk6 mice. Additionally, we isolated the goblet cells and determined the expression of Survivin by IF and protein validation. Tunicamycin was utilized at a concentration of 10 µg/mL to induce ERS in the LS174T cell line and the gene expression of the ERS markers was measured. This was followed by determination of inflammatory cytokines. Inhibition of ERS was carried out by 4Phenyl Butyric acid (4PBA) at a concentration of 10 mM to assess whether there was a reciprocation effect. The downstream cell death assays including caspase 3/7, Annexin V, and poly(ADP-ribose) polymerase (PARP) cleavage were evaluated in the presence of ERS and absence of ERS, which was followed by a proliferative assay (EdU click) with and without ERS. Correspondingly, we inhibited Survivin by YM155 at a concentration of 100 nM and observed the succeeding ERS markers and inflammatory markers. We also verified the caspase 3/7 assay. Our results demonstrate that ERS inhibition not only significantly reduced the UPR genes (Grp78, ATF6, PERKandXBP1) along with Survivin but also downregulated the inflammatory markers such as IL8, IL4, and IL6, which suggests a positive correlation between ERS and the inhibition of apoptosis. Furthermore, we provided evidence that ERS inhibition promoted apoptosis in LS174T cells and shortened the proliferation rate. Moreover, Survivin inhibition by YM155 led to a comparable effect as that of ERS inhibition, which includes attenuation of ERS genes and inflammatory markers as well as the promotion of programmed cell death via the caspase 3/7 pathway. Together, our results propose the interrelation between ERS and inhibition of apoptosis assigning a molecular and therapeutic target for cancer treatment.

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Epicatechin and its in vivo metabolite, 3′-O-methyl epicatechin, protect human fibroblasts from oxidative-stress-induced cell death involving caspase-3 activation

Biochemical Journal ◽

10.1042/bj3540493 ◽

2001 ◽

Vol 354 (3) ◽

pp. 493-500 ◽

Cited By ~ 69

Author(s):

Jeremy P. E. SPENCER ◽

Hagen SCHROETER ◽

Gunter KUHNLE ◽

S. Kaila S. SRAI ◽

Rex M. TYRRELL ◽

...

Keyword(s):

Oxidative Stress ◽

Hydrogen Peroxide ◽

Cell Death ◽

Caspase 3 ◽

Cell Damage ◽

Protective Action ◽

Human Fibroblasts ◽

Membrane Damage ◽

Antioxidant Properties

There is considerable current interest in the cytoprotective effects of natural antioxidants against oxidative stress. In particular, epicatechin, a major member of the flavanol family of polyphenols with powerful antioxidant properties in vitro, has been investigated to determine its ability to attenuate oxidative-stress-induced cell damage and to understand the mechanism of its protective action. We have induced oxidative stress in cultured human fibroblasts using hydrogen peroxide and examined the cellular responses in the form of mitochondrial function, cell-membrane damage, annexin-V binding and caspase-3 activation. Since one of the major metabolites of epicatechin in vivo is 3′-O-methyl epicatechin, we have compared its protective effects with that of epicatechin. The results provide the first evidence that 3′-O-methyl epicatechin inhibits cell death induced by hydrogen peroxide and that the mechanism involves suppression of caspase-3 activity as a marker for apoptosis. Furthermore, the protection elicited by 3′-O-methyl epicatechin is not significantly different from that of epicatechin, suggesting that hydrogen-donating antioxidant activity is not the primary mechanism of protection.

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Isoflavones Isolated from the Seeds of Millettia ferruginea Induced Apoptotic Cell Death in Human Ovarian Cancer Cells

Molecules ◽

10.3390/molecules25010207 ◽

2020 ◽

Vol 25 (1) ◽

pp. 207 ◽

Cited By ~ 2

Author(s):

Yi-Yue Wang ◽

Jun Hyeok Kwak ◽

Kyung-Tae Lee ◽

Tsegaye Deyou ◽

Young Pyo Jang ◽

...

Keyword(s):

Ovarian Cancer ◽

Cell Death ◽

Cancer Cells ◽

Caspase 3 ◽

Apoptotic Cell ◽

Apoptotic Cell Death ◽

Ovarian Cancer Cells ◽

Human Ovarian Cancer ◽

Millettia Ferruginea ◽

Induced Apoptosis

The seeds of Millettia ferruginea are used in fishing, pesticides, and folk medicine in Ethiopia. Here, the anti-cancer effects of isoflavones isolated from M. ferruginea were evaluated in human ovarian cancer cells. We found that isoflavone ferrugone and 6,7-dimethoxy-3’,4’-methylenedioxy-8-(3,3-dimethylallyl)isoflavone (DMI) had potent cytotoxic effects on human ovarian cancer cell A2780 and SKOV3. Ferrugone and DMI treatment increased the sub-G1 cell population in a dose-dependent manner in A2780 cells. The cytotoxic activity of ferrugone and DMI was associated with the induction of apoptosis, as shown by an increase in annexin V-positive cells. Z-VAD-fmk, a broad-spectrum caspase inhibitor, and z-DEVD-fmk, a caspase-3 inhibitor, significantly reversed both the ferrugone and DMI-induced apoptosis, suggesting that cell death stimulated by the isoflavones is mediated by caspase-3-dependent apoptosis. Additionally, ferrugone-induced apoptosis was found to be caspase-8-dependent, while DMI-induced apoptosis was caspase-9-dependent. Notably, DMI, but not ferrugone, increased the intracellular levels of reactive oxygen species (ROS), and antioxidant N-acetyl-L-cysteine (NAC) attenuated the pro-apoptotic activity of DMI. These data suggest that DMI induced apoptotic cell death through the intrinsic pathway via ROS production, while ferrugone stimulated the extrinsic pathway in human ovarian cancer cells.

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Myrcene Exhibits Antitumor Activity Against Lung Cancer Cells by Inducing Oxidative Stress and Apoptosis Mechanisms

Natural Product Communications ◽

10.1177/1934578x20961189 ◽

2020 ◽

Vol 15 (9) ◽

pp. 1934578X2096118

Author(s):

Xudong Bai ◽

Jin Tang

Keyword(s):

Oxidative Stress ◽

Lung Cancer ◽

Dna Damage ◽

Cell Death ◽

Cancer Cells ◽

Metabolic Activity ◽

Lung Cancer Cells ◽

Adenocarcinoma Cells ◽

Lung Adenocarcinoma Cells ◽

A549 Lung

Myrcene, a natural olefinic hydrocarbon, possesses anti-inflammatory, analgesic, antibiotic, and antimutagenic properties, but its anticancer effect has not yet been elucidated. Hence, the present study was framed to investigate the molecular mechanism by which myrcene mediates the anticancer activity of A549 lung adenocarcinoma cells. In vitro, A549 lung cancer cells were cultured either with or without myrcene, and the effects on cellular metabolic activity, levels of reactive oxygen species (ROS), mitochondrial integrity, deoxyribonucleic acid (DNA) damage, and activity of caspases were analyzed. The study demonstrated that compared with control cells, myrcene induces cell death in a dose-dependent manner while inducing ROS levels. Further experiments revealed that the metabolic activity of the A549 lung adenocarcinoma cells was diminished with increased DNA damage and altered cellular integrity. In addition, increased activity of caspase-3 was also evidenced with reduced mitochondrial membrane potential synthesis in the myrcene-treated cells, which demonstrate that lung cancer cells experience signs of toxicity during myrcene treatment through the activation of the apoptosis mechanism via mitochondria-mediated cell death signaling and induction of oxidative stress. The results provide the first report on the evidence of anticancer activity and the possibility of a new drug that could be used for the treatment of lung cancer.

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Increased Oxidative Stress Induced by Rubus Bioactive Compounds Induce Apoptotic Cell Death in Human Breast Cancer Cells

Oxidative Medicine and Cellular Longevity ◽

10.1155/2019/6797921 ◽

2019 ◽

Vol 2019 ◽

pp. 1-18 ◽

Cited By ~ 8

Author(s):

Blassan P. George ◽

Heidi Abrahamse

Keyword(s):

Breast Cancer ◽

Oxidative Stress ◽

Cell Death ◽

Cytochrome C ◽

Cancer Cells ◽

Bioactive Compounds ◽

Breast Cancer Cells ◽

Apoptotic Cell ◽

Ros Production ◽

Caspase 9

Bioactive compounds from plants represent good candidate drugs for the prevention and treatment of various forms of cancer. Berries are rich sources of bioactive compounds, and there has been an increasing interest in the study of therapeutic action of wild berries. Oxidants are generated continuously in biological system as a result of physiological process. When there is an imbalance between oxidants and antioxidants, it leads to a condition called oxidative stress. Natural compounds as inducers of oxidative stress are able to modulate the physiological functions of cancer cells leading to cell death or survival. The aim of this study was to evaluate the induction of apoptosis by isolated bioactive compounds (1-(2-hydroxyphenyl)-4-methylpentan-1-one (C1) and 2-[(3-methylbutoxy) carbonyl] benzoic acid (C2)) from Rubus fairholmianus against MCF-7 breast cancer cells. The exposure of C1 and C2 reduced viability (IC50 of C1: 4.69; C2: 8.36 μg/mL) and proliferation. Cytochrome c release from mitochondria and changes in mitochondrial membrane potential of treated cells supported the intrinsic apoptotic cell death. Reactive oxygen species (ROS) production after treatment with C1 and C2 was found to be higher and induced nuclear damage. Expression of apoptotic proteins after the treatments was significantly upregulated as indicated using immunofluorescence (caspase 9, p53, and Bax), western blotting (p53, cleaved PARP, cytochrome c, and Bax), and ELISA (caspase 9) analysis. Overall, C1 was more cytotoxic, increased the ROS production in dichlorodihydrofluorescein diacetate assay, and induced apoptosis in breast cancer cells. These results illustrate that berry bioactive compounds have strong chemopreventive potential. In this article, we provide information on prooxidant and anticancer activities of Rubus bioactive compounds. Natural products have always demonstrated a significant contribution to the development of several cancer chemotherapeutic drugs. Most of these compounds are known to affect the redox state of the cell; and studies on these compounds have focused on their antioxidant property instead of prooxidant properties.

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Effect of alpha-ketoglutarate and N-acetyl cysteine on cyanide-induced oxidative stress mediated cell death in PC12 cells

Toxicology and Industrial Health ◽

10.1177/0748233710365695 ◽

2010 ◽

Vol 26 (5) ◽

pp. 297-308 ◽

Cited By ~ 13

Author(s):

RM Satpute ◽

J. Hariharakrishnan ◽

R. Bhattacharya

Keyword(s):

Oxidative Stress ◽

Cell Death ◽

Pc12 Cells ◽

Caspase 3 ◽

Critical Role ◽

Total Antioxidant Status ◽

Protective Effects ◽

Simultaneous Treatment ◽

Acetyl Cysteine

Cyanide is a mitochondrial poison, which is ubiquitously present in the environment. Cyanide-induced oxidative stress is known to play a key role in mediating the neurotoxicity and cell death in rat pheochromocytoma (PC12) cells. PC12 cells are widely used as a model for neurotoxicity assays in vitro. In the present study, we investigated the protective effects of alpha-ketoglutarate (A-KG), a potential cyanide antidote, and N-acetyl cysteine (NAC), an antioxidant against toxicity of cyanide in PC12 cells. Cells were treated with various concentrations (0.625—1.25 mM) of potassium cyanide (KCN) for 4 hours, in the presence or absence of simultaneous treatment of A-KG (0.5 mM) and NAC (0.25 mM). Cyanide caused marked decrease in the levels of cellular antioxidants like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR). Lipid peroxidation indicated by elevated levels of malondialdehyde (MDA) was found to be accompanied by decreased levels of reduced glutathione (GSH) and total antioxidant status (TAS) of the cells. Cyanide-treated cells showed notable increase in caspase-3 activity and induction of apoptotic type of cell death after 24 hours. A-KG and NAC alone were very effective in restoring the levels of GSH and TAS, but together they significantly resolved the effects of cyanide on antioxidant enzymes, MDA levels, and caspase-3 activity. The present study reveals that combination of A-KG and NAC has critical role in abbrogating the oxidative stress-mediated toxicity of cyanide in PC12 cells. The results suggest potential role of A-KG and NAC in cyanide antagonism.

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