Synthetic Antibacterial Quaternary Phosphorus Salts Promote Methicillin-Resistant Staphylococcus aureus-Infected Wound Healing.

Background: Drug-resistant microbes pose a global health concern, requiring the urgent development of effective antibacterial agents and strategies in clinical practice. Therefore, there is an urgent need to explore novel antibacterial materials to effectively eliminate bacteria. The synthesis of quaternary phosphonium salt in haloargentate systems, wherein the phosphorus atom is represented in a cationic form, is a possible strategy for the development of antibacterial materials. Methods: Using (triphenyl)phosphonium-based quaternary phosphorus salts with different spacer lengths (n=2, 4, 6) as a template, we designed three kinds of quaternary phosphorus salts as effective antibacterial agents against drug-resistant bacteria. Results: The synthesized quaternary phosphorus salt of (1,4-DBTPP)Br2 effectively prevented the formation of the bacterial biofilms, and degraded bacterial membranes and cell walls by promoting the production of reactive oxygen species, which exhibited effective therapeutic effects in a rat model of a superficial wound infected with methicillin-resistant Staphylococcus aureus. Conclusion: The quaternary phosphorus salt (1,4-DBTPP)Br2 demonstrated hemocompatibility and low toxicity, revealing its potential in the treatment of clinical infections.

Comprehensive analysis of ferroptosis-related gene signatures as a potential therapeutic target for acute myeloid leukemia: A bioinformatics analysis and experimental verification.

Background: Ferroptosis plays an important role in the development of acute myeloid leukemia (AML); however, the exact role of ferroptosis-related genes in the prognosis of AML patients is unclear. Methods: RNA sequencing data and the clinicopathological characteristics of AML patients were obtained from The Cancer Genome Atlas database, and ferroptosis-related genes were obtained from the FerrDb database. Cox regression analysis and least absolute shrinkage and selection operator analysis were performed to identify ferroptosis-related gene signatures. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and single-sample gene set enrichment analysis (ssGSEA) were performed to explore the biological functions of the ferroptosis-related genes. Finally, ferroptosis of AML cells was induced by erastin and sulfasalazine to detect the changes in the expression of relevant prognostic genes and explore the underlying mechanisms using quantitative real-time polymerase chain reaction (qRT-PCR). Results: Seven ferroptosis-related gene signatures (SOCS1, ACSF2, MYB, EIF2AK4, AIFM2, SLC7A11, and GPX4) were identified in the training group. Kaplan-Meier and Cox regression analyses confirmed that risk score was an independent prognostic predictor of AML in the training and validation groups (P<0.05). Further, functional enrichment analysis revealed that seven ferroptosis-related genes were associated with many immune-related biological processes. Most importantly, erastin and sulfasalazine can induce the ferroptosis of AML cells. Overall, SLC7A11 and the SLC7A11/xCT-GSH-GPX4 pathway may be the respective key gene and potential regulatory pathway in erastin- and sulfasalazine-induced ferroptosis of AML cells. Conclusions: A novel signature involving seven ferroptosis-related genes that could accurately predict AML prognosis was identified. Further, the Food and Drug Administration-approved drug, sulfasalazine, was demonstrated for the first time to induce the ferroptosis of AML cells. SLC7A11 and the SLC7A11/xCT-GSH-GPX4 pathway may be the respective key gene and underlying mechanism in this process, ultimately providing new insights into the strategies for the development of new AML therapies.

TXNRD1: A Key Regulator Involved in the Ferroptosis of CML Cells Induced by Cysteine Depletion In Vitro.

Cysteine metabolism plays a critical role in cancer cell survival. Cysteine depletion was reported to inhibit tumor growth and induce pancreatic cancer cell ferroptosis. Nevertheless, the effect of cysteine depletion in chronic myeloid leukemia (CML) remains to be explored. In this work, we showed that cysteine depletion can induce K562/G01 but not K562 cell death in the form of ferroptosis. However, the glutathione (GSH)/glutathione peroxidase 4 (GPX4) pathways of the two CML cell lines were both blocked after cysteine depletion. This unexpected outcome guided us to perform RNA-Seq to screen the key genes that affect the sensitivity of CML cells to cysteine depletion. Excitingly, thioredoxin reductase 1 (TXNRD1), which related to cell redox metabolism, was significantly upregulated in K562/G01 cells after cysteine depletion. We further inferred that the upregulation is negatively feedback by the enzyme activity decrease of TXNRD1. Then, we triggered the ferroptosis by applying TXNRD1 shRNA and TXNRD1 inhibitor auranofin in K562 cells after cysteine depletion. In summary, we have reason to believe that TXNRD1 is a key regulator involved in the ferroptosis of CML cells induced by cysteine depletion in vitro. These findings highlight that cysteine depletion serves as a potential therapeutic strategy for overcoming chemotherapy resistance CML.

Identification of seven novel ferroptosis-related long non-coding RNA signatures as a diagnostic biomarker for acute myeloid leukemia.

BACKGROUND: Ferroptosis is a newly discovered type of programmed cell death that participates in the biological processes of various cancers. However, the mechanism by which ferroptosis modulates acute myeloid leukemia (AML) remains unclear. This study aimed to investigate the role of ferroptosis-related long non-coding RNAs (lncRNAs) in AML and establish a corresponding prognostic model. METHODS: RNA-sequencing data and clinicopathological characteristics were obtained from The Cancer Genome Atlas database, and ferroptosis-related genes were obtained from the FerrDb database. The "limma" R package, Cox regression, and the least absolute shrinkage and selection operator were used to determine the ferroptosis-related lncRNA signature with the lowest Akaike information criteria (AIC). The risk score of ferroptosis-related lncRNAs was calculated and patients with AML were divided into high- and low-risk groups based on the median risk score. The Kaplan-Meier curve and Cox regression were used to evaluate the prognostic value of the risk score. Finally, gene set enrichment analysis (GSEA) and single-sample gene set enrichment analysis (ssGSEA) were performed to explore the biological functions of the ferroptosis-related lncRNAs. RESULTS: Seven ferroptosis-related lncRNA signatures were identified in the training group, and Kaplan-Meier and Cox regression analyses confirmed that risk scores were independent prognostic predictors of AML in both the training and validation groups (All P < 0.05). In addition, the area under the curve (AUC) analysis confirmed that the signatures had a good predictive ability for the prognosis of AML. GSEA and ssGSEA showed that the seven ferroptosis-related lncRNAs were related to glutathione metabolism and tumor immunity. CONCLUSIONS: In this study, seven novel ferroptosis-related lncRNA signatures (AP001266.2, AC133961.1, AF064858.3, AC007383.2, AC008906.1, AC026771.1, and KIF26B-AS1) were established. These signatures were shown to accurately predict the prognosis of AML, which would provide new insights into strategies for the development of new AML therapies.