Idarubicin inhibits the growth of bacteria and yeasts in an automated blood culture system

Anticancer drugs targeting topoisomerase II for antifungal treatment

Fungal topoisomerase II (TopoII) has been identified as essential for viability. Thus, our research aimed to investigate the potential of fungal TopoII as a novel target for antifungal chemotherapy. We conducted studies on eleventh antitumor compounds targeting human topoisomerase II, either approved by the U.S. Food and Drug Administration (FDA) or currently under clinical trials to evaluate their potential for use in other therapeutic applications. While most of the compounds we analyzed are potent inhibitors of yeast TopoII, only a few exhibited antifungal activity. Idarubicin emerged as the most potent compound effectively inhibiting the growth of five reference fungal strains as well as clinical Candida glabrata fluconazole-resistant cells. Antifungal activity of this compound corresponded with its very high yeast TopoII inhibitory effectiveness. Additionally, idarubicin ability to be effectively accumulated into fungal cells is crucial for yeast TopoII targeting. Idarubicin, epirubicin, and bisantrene appeared to be even more effective inhibitors of yeast enzyme than its human counterpart. In fungal cells idarubicin exhibited a multifaceted mechanisms of action, including nuclear DNA fragmentation, disruption of mitochondrial network architecture and mitochondrial DNA aggregation as well as oxidative stress induction. Our results indicate that fungal topoisomerase II targeting is worth considering in antifungal treatment and the reported drugs may serve as a starting point for the reinnovation of a new molecule.

Recent advance of clinically approved small-molecule drugs for the treatment of myeloid leukemia

Myeloid leukemia denotes a hematologic malignancy characterized by aberrant proliferation and impaired differentiation of blood progenitor cells within the bone marrow. Despite the availability of several treatment options, the clinical outlook for individuals afflicted with myeloid leukemia continues to be unfavorable, making it a challenging disease to manage. Over the past, substantial endeavors have been dedicated to the identification of novel targets and the advancement of enhanced therapeutic modalities to ameliorate the management of this disease, resulting in the discovery of many clinically approved small-molecule drugs for myeloid leukemia, including histone deacetylase inhibitors, hypomethylating agents, and tyrosine kinase inhibitors. This comprehensive review succinctly presents an up-to-date assessment of the application and synthetic routes of clinically sanctioned small-molecule drugs employed in the treatment of myeloid leukemia. Additionally, it provides a concise exploration of the pertinent challenges and prospects encompassing drug resistance and toxicity. Overall, this review effectively underscores the considerable promise exhibited by clinically endorsed small-molecule drugs in the therapeutic realm of myeloid leukemia, while concurrently shedding light on the prospective avenues that may shape the future landscape of drug development within this domain.

Insights into idarubicin antimicrobial activity against methicillin-resistant Staphylococcus aureus

BACKGROUND

MRSA is a major concern in community settings and in health care. The emergence of biofilms and persister cells substantially increases its antimicrobial resistance. It is very urgent to develop new antimicrobials to solve this problem.

OBJECTIVE

Idarubicin was profiled to assess its antimicrobial effects in vitro and in vivo, and the underlying mechanisms.

METHODS

We investigated the antimicrobial effects of idarubicin against MRSA by time-kill analysis. The antibiofilm efficacy of idarubicin was assessed by crystal violet and XTT staining, followed by laser confocal microscopy observation. The mechanisms underlying the antimicrobial effects were studied by transmission electron microscopy, all-atom molecular dynamic simulations, SYTOX staining, surface plasma resonance, and DNA gyrase inhibition assay. Further, we addressed the antimicrobial efficacy in wound and subcutaneous abscess infection in vivo.

RESULTS

Idarubicin kills MRSA cells by disrupting the lipid bilayers and interrupting the DNA topoisomerase IIA subunits, and idarubicin shows synergistic antimicrobial effects with fosfomycin. Through synergy with a single dose treatment fosfomycin and the addition of the cell protector amifostine, the cytotoxicity and cardiotoxicity of idarubicin were significantly reduced without affecting its antimicrobial effects. Idarubicin alone or in combination with fosfomycin exhibited considerable efficacy in a subcutaneous abscess mouse model of MRSA infection. In addition, idarubicin also showed a low probability of causing resistance and good postantibiotic effects.

CONCLUSIONS

Idarubicin and its analogs have the potential to become a new class of antimicrobials for the treatment of MRSA-related infections.

In vitro antifungal activity of DNA topoisomerase inhibitors

In this paper we report the results of the study of the in vitro effect of eight anticancer DNA topoisomerase inhibitors on the growth of Aspergillus fumigatus, A. niger, Candida glabrata and Cryptococcus neoformans. Only one compound, idarubicin, displayed promising antifungal activity against A. niger, C. glabrata and C. neoformans with MIC(50) values varying between 3.6 and 14.2 μM (1.8-7.1 μg/ml). Three other compounds, aclarubicin, doxorubicin and mitoxantrone, showed some antifungal activity against C. glabrata and C. neoformans with MIC(50) values in the mid micromolar range. The data of this study indicate that selected DNA topoisomerase inhibitors are a promising class of compounds for the development of new antifungal agents.

Direct effects of non-antifungal agents used in cancer chemotherapy and organ transplantation on the development and virulence of Candida and Aspergillus species

Conventional antineoplastic, novel immunosuppressive agents and antibiotics used in cancer treatment can directly affect the growth, development and virulence of Candida and Aspergillus species. Cytotoxic and cisplatin compounds have anti-Candida activity and may be synergistic with antifungal drugs; they also inhibit Candida and Aspergillus filamentation/conidation and effect increased virulence in vitro. Glucocorticoids enhance Candida adherence to epithelial cells, germination in serum and in vitro secretion of phospholipases and proteases, as well as growth of A. fumigatus. Calcineurin and target of rapamycin inhibitors perturb Candida and Aspergillus morphogenesis, stress responses and survival in serum, reduce azole tolerance in Candida, but yield conflicting in vivo data. Inhibition of candidal heat shock protein 90 and candidal-specific histone deacetylase represent feasible therapeutic approaches for candidiasis. Tyrosine kinase inhibitors inhibit fungal cell entry into epithelial cells and phagocytosis. Quinolone and other antibiotics may augment activity of azole and polyene agents. The correlation of in vitro effects with clinically meaningful in vivo systems is warranted.