-
Nature Communications May 2024Checkpoint kinase 1 (CHK1) is critical for cell survival under replication stress (RS). CHK1 inhibitors (CHK1i's) in combination with chemotherapy have shown promising...
Checkpoint kinase 1 (CHK1) is critical for cell survival under replication stress (RS). CHK1 inhibitors (CHK1i's) in combination with chemotherapy have shown promising results in preclinical studies but have displayed minimal efficacy with substantial toxicity in clinical trials. To explore combinatorial strategies that can overcome these limitations, we perform an unbiased high-throughput screen in a non-small cell lung cancer (NSCLC) cell line and identify thioredoxin1 (Trx1), a major component of the mammalian antioxidant-system, as a determinant of CHK1i sensitivity. We establish a role for redox recycling of RRM1, the larger subunit of ribonucleotide reductase (RNR), and a depletion of the deoxynucleotide pool in this Trx1-mediated CHK1i sensitivity. Further, the TrxR inhibitor auranofin, an approved anti-rheumatoid arthritis drug, shows a synergistic interaction with CHK1i via interruption of the deoxynucleotide pool. Together, we show a pharmacological combination to treat NSCLC that relies on a redox regulatory link between the Trx system and mammalian RNR activity.
Topics: Checkpoint Kinase 1; Humans; Oxidation-Reduction; Thioredoxins; Cell Line, Tumor; Auranofin; Carcinoma, Non-Small-Cell Lung; Lung Neoplasms; Protein Kinase Inhibitors; Ribonucleoside Diphosphate Reductase; Ribonucleotide Reductases; Drug Synergism; Animals
PubMed: 38821952
DOI: 10.1038/s41467-024-48076-9 -
Journal of Applied Toxicology : JAT May 2017Auranofin (AF) is used in clinic for the treatment of rheumatoid arthritis, repurposing of AF as an anticancer drug has just finished a phase I/II clinical trial, but...
Auranofin (AF) is used in clinic for the treatment of rheumatoid arthritis, repurposing of AF as an anticancer drug has just finished a phase I/II clinical trial, but the developmental toxicity of AF remains obscure. This study focused on its developmental toxicity by using zebrafish embryos. Zebrafish embryos were exposed to different concentrations (1, 2.5, 5, 10 μm) of AF from 2 h post-fertilization (hpf) to 72 hpf. At 72 hpf, two major developmental defects caused by AF were found, namely severe pericardial edema and hypopigmentation, when embryos were exposed to concentrations higher than 2.5 μm. Biochemical detection of oxidative stress enzyme combined with expressions of a series of genes related to oxidative stress, cardiac, metal stress and pigment formation were subsequently tested. The superoxide dismutase activity was decreased while malondialdehyde content was accumulated by AF treatment. The expression of oxidative stress-related genes (sod1, gpx1a, gst), pigment-related genes (mitfb, trp-1a) and one metal stress-related gene ctr1 were all decreased by AF exposure. The expressions of cardiac-related genes (amhc, vmhc) and one metal-related gene hsp70 were found to be significantly upregulated by AF exposure. These findings indicated the potential developmental toxicity of AF on zebrafish early development. Copyright © 2016 John Wiley & Sons, Ltd.
Topics: Animals; Antirheumatic Agents; Auranofin; Edema; Embryo, Nonmammalian; Embryonic Development; Gene Expression Regulation, Developmental; Heart; Hypopigmentation; Malondialdehyde; Metals; Oxidative Stress; Stress, Physiological; Superoxide Dismutase; Teratogens; Zebrafish
PubMed: 27813112
DOI: 10.1002/jat.3410 -
Molecular Cancer Therapeutics Oct 2018We previously found that ibrutinib has anticancer activity in -mutant non-small cell lung cancer (NSCLC). One of our recent studies showed that auranofin, a gold complex...
We previously found that ibrutinib has anticancer activity in -mutant non-small cell lung cancer (NSCLC). One of our recent studies showed that auranofin, a gold complex that has been used to treat rheumatoid arthritis, inhibited the PI3K/AKT/mTOR pathway and promoted apoptosis in some NSCLC cells. Because the PI3K/AKT/mTOR pathway is one of the major downstream pathways of EGFR, we hypothesized that ibrutinib's activity might be enhanced by combination therapy with auranofin in NSCLC cells. To this end, we examined ibrutinib's dose responses in -mutant H1975, PC9, and H1650 cells and in wild-type Calu3 and H460 cells in the presence or absence of auranofin. Although low concentrations of auranofin alone demonstrated mild anticancer activities, its presence dramatically enhanced ibrutinib's activity in H1975, PC9, and H1650 cells (IC value reduced 10- to 100-fold), but had only mild effect on Calu3 and H460 cells, demonstrating that ibrutinib's anti-EGFR activity is enhanced when it is combined with auranofin. A mechanistic analysis revealed that ibrutinib alone induced dramatic inhibition of the MEK/ERK pathway in both H1975 and H1650 cells, whereas auranofin alone inhibited the AKT/mTOR pathway. The combination of ibrutinib and auranofin led to a dramatically enhanced inhibition of the expression or phosphorylation of multiple key nodes in the AKT/mTOR and MEK/ERK pathways in both cell lines. In mice, the combination of ibrutinib and auranofin significantly suppressed the growth of H1975 xenografted tumors without inducing obvious toxic effects. Our results demonstrate the feasibility of improving ibrutinib's anti-EGFR activity for NSCLC using combination therapy with auranofin. .
Topics: Adenine; Adenocarcinoma of Lung; Animals; Apoptosis; Auranofin; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cell Survival; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Synergism; ErbB Receptors; Humans; MAP Kinase Signaling System; Mice; Mutation; Piperidines; Pyrazoles; Pyrimidines; Xenograft Model Antitumor Assays
PubMed: 30065099
DOI: 10.1158/1535-7163.MCT-17-1173 -
Virulence Dec 2021The slowing-down drug-discovery emphasized the importance of repurposing old drugs. This is particularly true when combating infections caused by therapy-refractory...
The slowing-down drug-discovery emphasized the importance of repurposing old drugs. This is particularly true when combating infections caused by therapy-refractory microorganisms, such as species and . Recent studies on responses to oxidative stress underscored the importance of targeting the underlying mechanisms. Auranofin, ebselen, PX-12, honokiol, and to a lesser extent, conoidin A are known to disturb redox-homeostasis systems in many organisms. Their antifungal activity was assessed against 27 isolates belonging to the major species: , and . Auranofin and honokiol were the most active against all species (mean MIC values of 2.875 and 6.143 μg/ml, respectively) and against isolates (mean MIC values of 4.0 and 3.563μg/ml respectively). Combinations of auranofin with voriconazole or honokiol revealed additive effects against 9/27 and 18/27 isolates, respectively. Synergistic interaction between auranofin and honokiol was only found against one isolate of . The effects of auranofin upon exposure to oxidative stress were also investigated. For all species except , the maximal growth in the presence of auranofin significantly decreased when adding a sublethal dose of menadione. The analysis of the expression of genes encoding oxidoreductase enzymes upon exposure of to honokiol unveiled the upregulation of many genes, especially those coding peroxiredoxins, thioredoxin reductases, and glutaredoxins. Altogether, these data suggest that auranofin and honokiol act via dampening the redox balance and support their repurposing as antifungals against species and .
Topics: Antifungal Agents; Auranofin; Biphenyl Compounds; Drug Repositioning; Lignans; Scedosporium
PubMed: 33825667
DOI: 10.1080/21505594.2021.1909266 -
Breast Cancer Research and Treatment Dec 2021Tumor cells are dependent on the glutathione and thioredoxin antioxidant pathways to survive oxidative stress. Since the essential amino acid methionine is converted to...
PURPOSE
Tumor cells are dependent on the glutathione and thioredoxin antioxidant pathways to survive oxidative stress. Since the essential amino acid methionine is converted to glutathione, we hypothesized that methionine restriction (MR) would deplete glutathione and render tumors dependent on the thioredoxin pathway and its rate-limiting enzyme thioredoxin reductase (TXNRD).
METHODS
Triple (ER/PR/HER2)-negative breast cancer (TNBC) cells were treated with control or MR media and the effects on reactive oxygen species (ROS) and antioxidant signaling were examined. To determine the role of TXNRD in MR-induced cell death, TXNRD1 was inhibited by RNAi or the pan-TXNRD inhibitor auranofin, an antirheumatic agent. Metastatic and PDX TNBC mouse models were utilized to evaluate in vivo antitumor activity.
RESULTS
MR rapidly and transiently increased ROS, depleted glutathione, and decreased the ratio of reduced glutathione/oxidized glutathione in TNBC cells. TXNRD1 mRNA and protein levels were induced by MR via a ROS-dependent mechanism mediated by the transcriptional regulators NRF2 and ATF4. MR dramatically sensitized TNBC cells to TXNRD1 silencing and the TXNRD inhibitor auranofin, as determined by crystal violet staining and caspase activity; these effects were suppressed by the antioxidant N-acetylcysteine. H-Ras-transformed MCF-10A cells, but not untransformed MCF-10A cells, were highly sensitive to the combination of auranofin and MR. Furthermore, dietary MR induced TXNRD1 expression in mammary tumors and enhanced the antitumor effects of auranofin in metastatic and PDX TNBC murine models.
CONCLUSION
MR exposes a vulnerability of TNBC cells to the TXNRD inhibitor auranofin by increasing expression of its molecular target and creating a dependency on the thioredoxin pathway.
Topics: Animals; Auranofin; Humans; Methionine; Mice; Oxidation-Reduction; Thioredoxin Reductase 1; Thioredoxin-Disulfide Reductase; Triple Negative Breast Neoplasms
PubMed: 34553295
DOI: 10.1007/s10549-021-06398-y -
Cell Biochemistry and Function Dec 2023The intrinsic redox status of cancer cells limits the efficacy of chemotherapeutic drugs. Auranofin, a Food and Drug Administration-approved gold-containing compound,...
The intrinsic redox status of cancer cells limits the efficacy of chemotherapeutic drugs. Auranofin, a Food and Drug Administration-approved gold-containing compound, documented with effective pharmacokinetics and safety profiles in humans, has recently been repurposed for anticancer activity. This study examined the paclitaxel-sensitizing effect of auranofin by targeting redox balance in the MDA-MB-231 and MCF-7 breast cancer cell lines. Auranofin treatment depletes the activities of superoxide dismutase, catalase, and glutathione peroxidase and alters the redox ratio in the breast cancer cell lines. Furthermore, it has been noticed that auranofin augmented paclitaxel-mediated cytotoxicity in a concentration-dependent manner in both MDA-MB-231 and MCF-7 cell lines. Moreover, auranofin increased the levels of intracellular reactive oxygen species (observed using 2, 7-diacetyl dichlorofluorescein diacetate staining) and subsequently altered the mitochondrial membrane potential (rhodamine-123 staining) in a concentration-dependent manner. Further, the expression of apoptotic marker p21 was found to be higher in auranofin plus paclitaxel-treated breast cancer cells compared to paclitaxel-alone treatment. Thus, the present results illustrate the chemosensitizing property of auranofin in MDA-MB-231 and MCF-7 breast cancer cell lines via oxidative metabolism. Therefore, auranofin could be considered a chemosensitizing agent during cancer chemotherapy.
Topics: Humans; Female; Paclitaxel; Auranofin; Breast Neoplasms; Oxidation-Reduction; Cell Line, Tumor; MCF-7 Cells; Apoptosis
PubMed: 37792847
DOI: 10.1002/cbf.3865 -
International Journal of Molecular... Oct 2022Reactive oxygen species (ROS) homeostasis and mitochondrial metabolism are critical for the survival of cancer cells, including cancer stem cells (CSCs), which often...
Reactive oxygen species (ROS) homeostasis and mitochondrial metabolism are critical for the survival of cancer cells, including cancer stem cells (CSCs), which often cause drug resistance and cancer relapse. Auranofin is a mono-gold anti-rheumatic drug, and it has been repurposed as an anticancer agent working by the induction of both ROS increase and mitochondrial dysfunction. Hypothetically, increasing auranofin's positive charges via incorporating more gold atoms to enhance its mitochondria-targeting capacity could enhance its anti-cancer efficacy. Hence, in this work, both mono-gold and bi-gold compounds were designed and evaluated to test our hypothesis. The results showed that bi-gold compounds generally suppressed cancer cells proliferation better than their mono-gold counterparts. The most potent compound, BGC2a, substantially inhibited the antioxidant enzyme TrxR and increased the cellular ROS. BGC2a induced cell apoptosis, which could not be reversed by the antioxidant agent vitamin C, implying that the ROS induced by TrxR inhibition might not be the decisive cause of cell death. As expected, a significant proportion of BGC2a accumulated within mitochondria, likely contributing to mitochondrial dysfunction, which was further confirmed by measuring oxygen consumption rate, mitochondrial membrane potential, and ATP production. Moreover, BGC2a inhibited colony formation and reduced stem-like side population (SP) cells of A549. Finally, the compound effectively suppressed the tumor growth of both A549 and PANC-1 xenografts. Our study showed that mitochondrial disturbance may be gold-based compounds' major lethal factor in eradicating cancer cells, providing a new approach to developing potent gold-based anti-cancer drugs by increasing mitochondria-targeting capacity.
Topics: Humans; Reactive Oxygen Species; Auranofin; Antioxidants; Mitochondria; Apoptosis; Gold Compounds; Ascorbic Acid; Antirheumatic Agents; Adenosine Triphosphate; Cell Proliferation; Cell Line, Tumor; Neoplasms
PubMed: 36293028
DOI: 10.3390/ijms232012169 -
Journal of Medicinal Chemistry Sep 2019Auranofin, an FDA-approved arthritis drug, has recently been repurposed as a potential antimicrobial agent; it performed well against many Gram-positive bacteria,...
Auranofin, an FDA-approved arthritis drug, has recently been repurposed as a potential antimicrobial agent; it performed well against many Gram-positive bacteria, including multidrug resistant strains. It is, however, inactive toward Gram-negative bacteria, for which we are in dire need of new therapies. In this work, 40 auranofin analogues were synthesized by varying the structures of the thiol and phosphine ligands, and their activities were tested against ESKAPE pathogens. The study identified compounds that exhibited bacterial inhibition (MIC) and killing (MBC) activities up to 65 folds higher than that of auranofin, making them effective against Gram-negative pathogens. Both thiol and the phosphine structures influence the activities of the analogues. The trimethylphosphine and triethylphosphine ligands gave the highest activities against Gram-negative and Gram-positive bacteria, respectively. Our SAR study revealed that the thiol ligand is also very important, the structure of which can modulate the activities of the Au complexes for both Gram-negative and Gram-positive bacteria. Moreover, these analogues had mammalian cell toxicities either similar to or lower than that of auranofin.
Topics: A549 Cells; Anti-Bacterial Agents; Antirheumatic Agents; Auranofin; Cell Survival; Dose-Response Relationship, Drug; Gram-Negative Aerobic Bacteria; Gram-Positive Bacteria; Humans; Microbial Sensitivity Tests; Molecular Structure; Structure-Activity Relationship; Tumor Cells, Cultured
PubMed: 31386365
DOI: 10.1021/acs.jmedchem.9b00550 -
Antimicrobial Agents and Chemotherapy Jan 2017Under an NIH priority to identify new drugs to treat class B parasitic agents, we performed high-throughput screens, which identified the activity of auranofin (Ridaura)...
Under an NIH priority to identify new drugs to treat class B parasitic agents, we performed high-throughput screens, which identified the activity of auranofin (Ridaura) against Entamoeba histolytica and Giardia intestinalis, major causes of water- and foodborne outbreaks. Auranofin, an orally administered, gold (Au)-containing compound that was approved by the FDA in 1985 for treatment of rheumatoid arthritis, was effective in vitro and in vivo against E. histolytica and both metronidazole-sensitive and -resistant strains of Giardia We now report the results of an NIH-sponsored phase I trial to characterize the pharmacokinetics (PK) and safety of auranofin in healthy volunteers using modern techniques to measure gold levels. Subjects received orally 6 mg (p.o.) of auranofin daily, the recommended dose for rheumatoid arthritis, for 7 days and were followed for 126 days. Treatment-associated adverse events were reported by 47% of the subjects, but all were mild and resolved without treatment. The mean gold maximum concentration in plasma (C) at day 7 was 0.312 μg/ml and the half-life (t) 35 days, so steady-state blood levels would not be reached in short-term therapy. The highest concentration of gold, 13 μM (auranofin equivalent), or more than 25× the 50% inhibitory concentration (IC) for E. histolytica and 4× that for Giardia, was in feces at 7 days. Modeling of higher doses (9 and 21 mg/day) was performed for systemic parasitic infections, and plasma gold levels of 0.4 to 1.0 μg/ml were reached after 14 days of treatment at 21 mg/day. This phase I trial supports the idea of the safety of auranofin and provides important PK data to support its potential use as a broad-spectrum antiparasitic drug. (This study has been registered at ClinicalTrials.gov under identifier NCT02089048.).
Topics: Administration, Oral; Adult; Antiparasitic Agents; Antirheumatic Agents; Auranofin; Computer Simulation; Drug Administration Schedule; Drug Dosage Calculations; Drug Repositioning; Entamoeba histolytica; Female; Giardia lamblia; Gold; Half-Life; Healthy Volunteers; High-Throughput Screening Assays; Humans; Inhibitory Concentration 50; Male; Metronidazole; Models, Statistical; Tissue Distribution
PubMed: 27821451
DOI: 10.1128/AAC.01947-16 -
International Journal of Antimicrobial... May 2022Infections caused by multidrug-resistant (MDR) bacteria, especially MDR Gram-negative bacteria, have posed a great challenge to healthcare systems globally. To address...
OBJECTIVES
Infections caused by multidrug-resistant (MDR) bacteria, especially MDR Gram-negative bacteria, have posed a great challenge to healthcare systems globally. To address the shortage of effective antibiotics against MDR Gram-negative bacterial infections, two non-antibiotic drugs - auranofin (rheumatoid arthritis drug) and pentamidine (antiprotozoal drug) - are being repurposed to treat MDR Gram-negative bacteria by a combination approach.
METHODS
Chequerboard microdilution assay was used to determine the interaction of auranofin and pentamidine against drug-susceptible and MDR Gram-negative bacteria (Escherichia coli, Acinetobacter baumannii and Klebsiella pneumoniae). Fluorescence microscopy, scanning electron microscopy and inductively coupled plasma mass spectrometry were used to explore the mechanism of synergistic antibacterial effect.
RESULTS
These two non-antibiotic drugs displayed a strong synergistic antibacterial effect, with the fraction inhibitory concentration index ranging 0.094-0.506. The MIC of auranofin reduced by as much as ≥ 1024-fold when combined with pentamidine at sub-MIC. Fluorescence and inductively coupled plasma mass spectrometry analyses revealed that bacterial membrane disruption caused by pentamidine treatment at sub-MIC led to an increased intracellular auranofin content with the combination treatment. The enhanced auranofin uptake in bacteria resulted in efficient bacterial killing. More importantly, the auranofin/pentamidine combination slowed down auranofin resistance development in clinically isolated MDR bacteria (Klebsiella pneumoniae) more than the combination of auranofin and colistin, which is a last-line antibiotic with a membrane-lytic antibacterial mechanism.
CONCLUSION
The combination of non-antibiotic drugs with complementary antibacterial mechanisms provides a potentially promising approach to discover new antibacterial drugs and delay drug resistance development.
Topics: Anti-Bacterial Agents; Auranofin; Drug Repositioning; Drug Resistance, Multiple, Bacterial; Drug Synergism; Escherichia coli; Gram-Negative Bacteria; Klebsiella pneumoniae; Microbial Sensitivity Tests; Pentamidine
PubMed: 35378227
DOI: 10.1016/j.ijantimicag.2022.106582