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International Journal of Antimicrobial... Sep 2023Escherichia coli is an important pathogen responsible for numerous cases of diarrhoea worldwide. The bioreductive agent tirapazamine (TPZ), which was clinically used to...
OBJECTIVES
Escherichia coli is an important pathogen responsible for numerous cases of diarrhoea worldwide. The bioreductive agent tirapazamine (TPZ), which was clinically used to treat various types of cancers, has obvious antibacterial activity against E. coli strains. In the present study, we aimed to evaluate the protective therapeutic effects of TPZ in E. coli-infected mice and provide insights into its antimicrobial action mechanism.
METHODS
The MIC and MBC tests, drug sensitivity test, crystal violet assay and proteomic analysis were used to detect the in vitro antibacterial activity of TPZ. The clinical symptoms of infected mice, tissue bacteria load, histopathological features and gut microbiota changes were regarded as indicators to evaluation the efficacy of TPZ in vivo.
RESULTS
Interestingly, TPZ-induced the reversal of drug resistance in E. coli by regulating the expression of resistance-related genes, which may have an auxiliary role in the clinical treatment of drug-resistant bacterial infections. More importantly, the proteomics analysis showed that TPZ upregulated 53 proteins and downregulated 47 proteins in E. coli. Among these, the bacterial defence response-related proteins colicin M and colicin B, SOS response-related proteins RecA, UvrABC system protein A, and Holliday junction ATP-dependent DNA helicase RuvB were all significantly upregulated. The quorum sensing-related protein glutamate decarboxylase, ABC transporter-related protein glycerol-3-phosphate transporter polar-binding protein, and ABC transporter polar-binding protein YtfQ were significantly downregulated. The oxidoreductase activity-related proteins pyridine nucleotide-disulfide oxidoreductase, glutaredoxin 2 (Grx2), NAD(+)-dependent aldehyde reductase, and acetaldehyde dehydrogenase, which participate in the elimination of harmful oxygen free radicals in the oxidation-reduction process pathway, were also significantly downregulated. Moreover, TPZ improved the survival rate of infected mice; significantly reduced the bacteria load in the liver, spleen, and colon; and alleviated E. coli-associated pathological damages. The gut microbiota also changed in TPZ-treated mice, and these genera were considerably differentiated: Candidatus Arthromitus, Eubacterium coprostanoligenes group, Prevotellaceae UCG-001, Actinospica, and Bifidobacterium.
CONCLUSIONS
TPZ may represent an effective and promising lead molecule for the development of antimicrobial agents for the treatment of E. coli infections.
Topics: Animals; Mice; Tirapazamine; Escherichia coli; Antineoplastic Agents; Triazines; Proteomics; Oxidoreductases; Anti-Bacterial Agents
PubMed: 37433388
DOI: 10.1016/j.ijantimicag.2023.106923 -
Frontiers in Bioengineering and... 2023Cancer selectivity, including targeted internalization and accelerated drug release in tumor cells, remains a major challenge for designing novel stimuli-responsive...
Cancer selectivity, including targeted internalization and accelerated drug release in tumor cells, remains a major challenge for designing novel stimuli-responsive nanocarriers to promote therapeutic efficacy. The hypoxic microenvironment created by photodynamic therapy (PDT) is believed to play a critical role in chemoresistance. We construct dual-responsive carriers (NP) that encapsulate the photosensitizer chlorin e6 (Ce6) and hypoxia-activated prodrug tirapazamine (TPZ) to enable efficient PDT and PDT-boosted hypoxia-activated chemotherapy. Due to TAT masking, NP prolonged payload circulation in the bloodstream, and selective tumor cell uptake occurred via acidity-triggered TAT presentation. PDT was performed with a spatially controlled 660-nm laser to enable precise cell killing and exacerbate hypoxia. Hypoxia-responsive conversion of the hydrophobic NI moiety led to the disassembly of NP, facilitating TPZ release. TPZ was reduced to cytotoxic radicals under hypoxic conditions, contributing to the chemotherapeutic cascade. This work offers a sophisticated strategy for programmed chemo-PDT.
PubMed: 37362218
DOI: 10.3389/fbioe.2023.1197404 -
Cancers May 2023Hypoxia-inducible factor 1 alpha (HIF-1α) is a transcription factor that regulates the cellular response to hypoxia and is upregulated in all types of solid tumor,... (Review)
Review
Hypoxia-inducible factor 1 alpha (HIF-1α) is a transcription factor that regulates the cellular response to hypoxia and is upregulated in all types of solid tumor, leading to tumor angiogenesis, growth, and resistance to therapy. Hepatocellular carcinoma (HCC) is a highly vascular tumor, as well as a hypoxic tumor, due to the liver being a relatively hypoxic environment compared to other organs. Trans-arterial chemoembolization (TACE) and trans-arterial embolization (TAE) are locoregional therapies that are part of the treatment guidelines for HCC but can also exacerbate hypoxia in tumors, as seen with HIF-1α upregulation post-hepatic embolization. Hypoxia-activated prodrugs (HAPs) are a novel class of anticancer agent that are selectively activated under hypoxic conditions, potentially allowing for the targeted treatment of hypoxic HCC. Early studies targeting hypoxia show promising results; however, further research is needed to understand the effects of HAPs in combination with embolization in the treatment of HCC. This review aims to summarize current knowledge on the role of hypoxia and HIF-1α in HCC, as well as the potential of HAPs and liver-directed embolization.
PubMed: 37345074
DOI: 10.3390/cancers15102738 -
Acta Biomaterialia Sep 2023Glutathione (GSH) consumption-enhanced cancer therapies represent important potential cancer treatment strategies. Herein, we developed a new multifunctional...
Glutathione (GSH) consumption-enhanced cancer therapies represent important potential cancer treatment strategies. Herein, we developed a new multifunctional diselenide-crosslinked hydrogel with glutathione peroxidase (GPx)-like catalytic activity for GSH depletion-enhanced glucose oxidase (GOx)-mediated tumor starvation and hypoxia-activated chemotherapy. By increasing acid and HO during GOx-induced tumor starvation, the degradation of the multiresponsive scaffold could be promoted, which led to accelerated release of the loaded drugs. Meanwhile, the overproduced HO led to accelerated intracellular GSH consumption under the cascade catalysis of small molecular selenides released from the degraded hydrogel, further enhancing the curative effect of in situ HO and subsequent multimodal cancer treatment. Following the GOx-induced amplification of hypoxia, tirapazamine (TPZ) was transformed into the highly toxic benzotriazinyl radical (BTZ·), exhibiting enhanced antitumor activity. This GSH depletion-augmented cancer treatment strategy effectively boosted GOx-mediated tumor starvation and activated the hypoxia drug, leading to significantly enhanced local anticancer efficacy. STATEMENT OF SIGNIFICANCE: There has been a growing interest in depleting intracellular GSH as a potential strategy for improving ROS-based cancer therapy. Herein, a bioresponsive diselenide-functionalized dextran-based hydrogel with GPx-like catalytic activity was developed for GSH consumption-enhanced local starvation- and hypoxia-activated melanoma therapy. Results showed that the overproduced HO led to accelerated intracellular GSH consumption under the cascade catalysis of small molecular selenides released from the degraded hydrogel, further enhancing the curative effect of in situ HO and subsequent multimodal cancer treatment.
Topics: Humans; Hydrogen Peroxide; Hydrogels; Neoplasms; Melanoma; Combined Modality Therapy; Hypoxia; Cell Line, Tumor; Tumor Microenvironment
PubMed: 37339693
DOI: 10.1016/j.actbio.2023.06.017 -
Advanced Healthcare Materials Dec 2023Blockage of blood supply while administering chemotherapy to tumors, using trans-arterial chemoembolization (TACE), is the most common treatment for intermediate and...
Blockage of blood supply while administering chemotherapy to tumors, using trans-arterial chemoembolization (TACE), is the most common treatment for intermediate and advanced-stage unresectable Hepatocellular carcinoma (HCC). However, HCC is characterized by a poor prognosis and high recurrence rates (≈30%), partly due to a hypoxic pro-angiogenic and pro-cancerous microenvironment. This study investigates how modifying tissue stress while improving drug exposure in target organs may maximize the therapeutic outcomes. Porous degradable polymeric microspheres (MS) are designed to obtain a gradual occlusion of the hepatic artery that nourishes the liver, while enabling efficient drug perfusion to the tumor site. The fabricated porous MS are introduced intrahepatically and designed to release a combination therapy of Doxorubicin (DOX) and Tirapazamine (TPZ), which is a hypoxia-activated prodrug. Liver cancer cell lines that are treated with the combination therapy under hypoxia reveal a synergic anti-proliferation effect. An orthotopic liver cancer model, based on N1-S1 hepatoma in rats, is used for the efficacy, biodistribution, and safety studies. Porous DOX-TPZ MS are very effective in suppressing tumor growth in rats, and induction tissue necrosis is associated with high intratumor drug concentrations. Porous particles without drugs show some advantages over nonporous particles, suggesting that morphology may affect the treatment outcomes.
Topics: Rats; Animals; Liver Neoplasms; Carcinoma, Hepatocellular; Microspheres; Tissue Distribution; Porosity; Chemoembolization, Therapeutic; Doxorubicin; Tirapazamine; Hypoxia; Tumor Microenvironment
PubMed: 37315950
DOI: 10.1002/adhm.202301548 -
Microbiology Spectrum Aug 2023Pseudomonas aeruginosa is the most common pathogen infecting cystic fibrosis (CF) lungs, causing acute and chronic infections. Intrinsic and acquired antibiotic...
Repurposing High-Throughput Screening Identifies Unconventional Drugs with Antibacterial and Antibiofilm Activities against Pseudomonas aeruginosa under Experimental Conditions Relevant to Cystic Fibrosis.
Pseudomonas aeruginosa is the most common pathogen infecting cystic fibrosis (CF) lungs, causing acute and chronic infections. Intrinsic and acquired antibiotic resistance allow P. aeruginosa to colonize and persist despite antibiotic treatment, making new therapeutic approaches necessary. Combining high-throughput screening and drug repurposing is an effective way to develop new therapeutic uses for drugs. This study screened a drug library of 3,386 drugs, mostly FDA approved, to identify antimicrobials against P. aeruginosa under physicochemical conditions relevant to CF-infected lungs. Based on the antibacterial activity, assessed spectrophotometrically against the prototype RP73 strain and 10 other CF virulent strains, and the toxic potential evaluated toward CF IB3-1 bronchial epithelial cells, five potential hits were selected for further analysis: the anti-inflammatory and antioxidant ebselen, the anticancer drugs tirapazamine, carmofur, and 5-fluorouracil, and the antifungal tavaborole. A time-kill assay showed that ebselen has the potential to cause rapid and dose-dependent bactericidal activity. The antibiofilm activity was evaluated by viable cell count and crystal violet assays, revealing carmofur and 5-fluorouracil as the most active drugs in preventing biofilm formation regardless of the concentration. In contrast, tirapazamine and tavaborole were the only drugs actively dispersing preformed biofilms. Tavaborole was the most active drug against CF pathogens other than P. aeruginosa, especially against Burkholderia cepacia and Acinetobacter baumannii, while carmofur, ebselen, and tirapazamine were particularly active against Staphylococcus aureus and B. cepacia. Electron microscopy and propidium iodide uptake assay revealed that ebselen, carmofur, and tirapazamine significantly damage cell membranes, with leakage and cytoplasm loss, by increasing membrane permeability. Antibiotic resistance makes it urgent to design new strategies for treating pulmonary infections in CF patients. The repurposing approach accelerates drug discovery and development, as the drugs' general pharmacological, pharmacokinetic, and toxicological properties are already well known. In the present study, for the first time, a high-throughput compound library screening was performed under experimental conditions relevant to CF-infected lungs. Among 3,386 drugs screened, the clinically used drugs from outside infection treatment ebselen, tirapazamine, carmofur, 5-fluorouracil, and tavaborole showed, although to different extents, anti-P. aeruginosa activity against planktonic and biofilm cells and broad-spectrum activity against other CF pathogens at concentrations not toxic to bronchial epithelial cells. The mode-of-action studies revealed ebselen, carmofur, and tirapazamine targeted the cell membrane, increasing its permeability with subsequent cell lysis. These drugs are strong candidates for repurposing for treating CF lung P. aeruginosa infections.
Topics: Humans; Pseudomonas aeruginosa; Cystic Fibrosis; High-Throughput Screening Assays; Drug Repositioning; Tirapazamine; Anti-Bacterial Agents; Fluorouracil; Biofilms; Pseudomonas Infections
PubMed: 37306577
DOI: 10.1128/spectrum.00352-23 -
Materials Horizons Jul 2023Phototherapy-induced hypoxia in the tumor microenvironment (TME) is responsible for diminished therapeutic efficacy. Designing an intelligent nanosystem capable of...
Phototherapy-induced hypoxia in the tumor microenvironment (TME) is responsible for diminished therapeutic efficacy. Designing an intelligent nanosystem capable of responding to hypoxia for TME-responsive drug delivery will, to some extent, improve the therapeutic efficacy and reduce side effects. Semiconducting polymers with high photothermal conversion efficiency and photostability have tremendous potential as phototheranostics. In this paper, hypoxia-activatable tirapazamine (TPZ) was conjugated onto poly(ethylene glycol) to form a pH-sensitive poly-prodrug, PEG-TPZ, that can be triggered by the low acidity of the TME to cleave the acylamide bond for controllable drug release. PEG-TPZ was then used to encapsulate a semiconducting polymer (TDPP) for NIR-II-fluorescence-imaging-guided synergistic therapy. The reactive oxygen species (ROS) generation and ultrahigh photothermal conversion efficiency (∼58.6%) of the TDPP@PEG-TPZ NPs leads to the destruction of the tumor blood vessels, thus further activating the hypoxia-induced chemotherapy of TPZ. As a result, effective tumor regression was achieved after laser irradiation.
PubMed: 37194333
DOI: 10.1039/d3mh00242j -
MethodsX 2023Tirapazamine (TPZ), a hypoxia-selective cytotoxic agent, has proved to exert synergistic tumor-killing activity with transcatheter arterial embolization (TAE) against...
Tirapazamine (TPZ), a hypoxia-selective cytotoxic agent, has proved to exert synergistic tumor-killing activity with transcatheter arterial embolization (TAE) against liver cancer. This advances TPZ to transcatheter therapies for liver cancer, particularly in combination with drug-eluting microspheres. We describe methods for preparing and characterizing TPZ-loaded CalliSpheres microspheres (CSMTPZs) with regard to their properties as a chemoembolization agent, which includes 1) preparation of CSMTPZs and determination of drug loading level, 2) determination of TPZ release, 3) assessment of CSMTPZ size and appearance, and 4) determination of TPZ pharmacokinetics and intratumoral drug concentration . These methods can be adapted for further clinical I trial.•This is to our knowledge the first methods for preparing and characterizing tirapazamine-loaded microspheres with regard to their properties as a chemoembolization agent•Detailed protocols for preparation of CSMTPZs, determination of drug loading level, determination of TPZ release, assessment of CSMTPZ size and appearance, and determination of TPZ pharmacokinetics and intratumoral drug concentration•Adaptable to experiments on other animal models and clinical trials.
PubMed: 37168773
DOI: 10.1016/j.mex.2023.102188 -
Advanced Materials (Deerfield Beach,... Aug 2023Inducing immunogenic cell death (ICD) by sonodynamic therapy (SDT) is promising for cancer immunotherapy, which however is inefficient due to oxygen depletion that...
Inducing immunogenic cell death (ICD) by sonodynamic therapy (SDT) is promising for cancer immunotherapy, which however is inefficient due to oxygen depletion that compromises SDT effect and mediates recruitment of immunosuppressive myeloid-derived suppressor cells (MDSCs). The fabrication of sono-activatable semiconducting polymer nanopartners (SPN ) to simultaneously augment ICD and alleviate MDSCs for immunotherapy is reported. A sonodynamic semiconducting polymer, hydrophobic hypoxia-responsive tirapazamine (TPZ)-conjugate, and MDSC-targeting drug (ibrutinib) are encapsulated inside such SPN with surface shell of a singlet oxygen ( O )-cleavable amphiphilic polymer. TPZ and ibrutinib serve as drug partners to enlarge immunotherapeutic effect. Upon sono-activation, SPN generate O to break O -cleavable polymers for in situ liberations of TPZ-conjugate and ibrutinib in tumor sites, and oxygen is consumed to create severe hypoxic tumor microenvironment, in which, TPZ-conjugate is activated for augmenting ICD action, while ibrutinib alleviates MDSCs for promoting antitumor immunological effect. In a bilateral tumor mouse model, SPN -mediated sono-activatable immunotherapy results in growth restraints of primary and distant tumors and noteworthy precaution of tumor metastases. This study thus provides a sono-activatable immunotherapeutic strategy with high precision and safety for cancer via overcoming post-treatment hypoxia and targeting MDSCs.
Topics: Animals; Mice; Myeloid-Derived Suppressor Cells; Polymers; Immunogenic Cell Death; Neoplasms; Tirapazamine; Immunotherapy; Hypoxia; Oxygen; Tumor Microenvironment; Cell Line, Tumor
PubMed: 37165741
DOI: 10.1002/adma.202302508 -
Advanced Science (Weinheim,... Aug 2023As a currently common strategy to treat cancer, surgical resection may cause tumor recurrence and metastasis due to residual postoperative tumors. Herein, an implantable...
Sandwich-Structured Implants to Obstruct Multipath Energy Supply and Trigger Self-Enhanced Hypoxia-Initiated Chemotherapy Against Postsurgical Tumor Recurrence and Metastasis.
As a currently common strategy to treat cancer, surgical resection may cause tumor recurrence and metastasis due to residual postoperative tumors. Herein, an implantable sandwich-structured dual-drug depot is developed to trigger a self-intensified starvation therapy and hypoxia-induced chemotherapy sequentially. The two outer layers are 3D-printed using a calcium-crosslinked mixture ink containing soy protein isolate, polyvinyl alcohol, sodium alginate, and combretastatin A4 phosphate (CA4P). The inner layer is one patch of poly (lactic-co-glycolic acid)-based electrospun fibers loaded with tirapazamine (TPZ). The preferentially released CA4P destroys the preexisting blood vessels and prevents neovascularization, which obstructs the external energy supply to cancer cells but aggravates hypoxic condition. The subsequently released TPZ is bioreduced to cytotoxic benzotriazinyl under hypoxia, further damaging DNA, generating reactive oxygen species, disrupting mitochondria, and downregulating hypoxia-inducible factor 1α, vascular endothelial growth factor, and matrix metalloproteinase 9. Together these processes induce apoptosis, block the intracellular energy supply, counteract the disadvantage of CA4P in favoring intratumor angiogenesis, and suppress tumor metastasis. The in vivo and in vitro results and the transcriptome analysis demonstrate that the postsurgical adjuvant treatment with the dual-drug-loaded sandwich-like implants efficiently inhibits tumor recurrence and metastasis, showing great potential for clinical translation.
Topics: Humans; Neoplasm Recurrence, Local; Vascular Endothelial Growth Factor A; Cell Line, Tumor; Antineoplastic Agents; Tirapazamine; Hypoxia
PubMed: 37156756
DOI: 10.1002/advs.202300899