Clotrimazole as a Cancer Drug: A Short Review

Oxidative effects of the human antifungal drug clotrimazole on the eucaryotic model organism Saccharomyces cerevisiae

Clotrimazole is a type of antifungal medication developed from azole compounds. It exhibits several biological actions linked to oxidative stress. This study focuses on the oxidative effects of clotrimazole on the eukaryotic model yeast, Saccharomyces cerevisiae. Our results showed that although initial nitric oxide levels were above control in clotrimazole exposed cells, they showed decreasing tendencies from the beginning of incubation and dropped below control at 125 µM from the 60th min. The highest superoxide anion and hydrogen peroxide levels were 1.95- and 2.85-folds of controls at 125 µM after 15 and 60 min, respectively. Hydroxyl radical levels slightly increased throughout the incubation period in all concentrations and reached 1.3-fold of control, similarly at 110 and 125 µM in the 90th min. The highest level of reactive oxygen species was observed at 110 µM, 2.31-fold of control. Although NADH/NADPH oxidase activities showed similar tendencies for all conditions, the highest activities were found as 3.07- and 2.27-folds of control at 125 and 110 µM in the 15th and 30th min, respectively. The highest superoxide dismutase and catalase activities were 1.59- and 1.21-folds of controls at 110 µM clotrimazole in 30 and 90 min, respectively. While the drug generally induced glutathione-related enzyme activities, the ratios of glutathione to oxidized glutathione were above the control only at low concentrations of the drug. The levels of lipid peroxidation in all treated cells were significantly higher than the controls. The findings crucially demonstrate that this medicine can generate serious oxidative stress in organisms.

Unraveling the Molecular Complexity of Adenoid Cystic Carcinoma (ACC): A Comprehensive Exploration of Hub Genes, Protein-Protein Interaction (PPI) Networks, microRNA (miRNA) Involvement, and Drug-Gene Interactions (DGIs)

Background Adenoid cystic carcinoma (ACC) poses clinical challenges with its unique histology and potential for perineural invasion, recurrence, and distant metastases. Recent genomic advancements have unveiled key genetic alterations in ACC, offering insights into its pathogenesis. Aim This study aims to unravel the intricate molecular landscape of ACC through a comprehensive analysis of gene expression patterns. By integrating data from multiple microarray datasets, the study explores differentially expressed genes (DEGs), their functional enrichment, protein-protein interactions (PPI), hub genes, microRNA (miRNA) involvement, transcription factors, and potential drug-gene interactions. Methods Three microarray datasets (GSE88804, GSE153002, and GSE36820) related to ACC were selected from the Gene Expression Omnibus (GEO) repository. DEGs were identified using GEO2R and further analyzed for commonalities and differences. Functional enrichment analysis, including Gene Set Enrichment Analysis (GSEA), provided insights into biological processes, cellular components, molecular functions, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with ACC. PPI networks and hub genes were identified using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) (STRING Consortium, Lausanne, Switzerland) database and Cytoscape (Cytoscape Consortium, California, United States). The study also explored miRNAs, transcription factors, and potential drug-gene interactions. Results The integrated analysis revealed 339 common upregulated and 643 downregulated DEGs in ACC. Functional and pathway enrichment analyses unveiled the involvement of these genes in critical cellular processes, signaling cascades, and pathways. The PPI network, comprising 904 nodes and 4139 edges, highlighted the complexity of interactions. Hub genes, including KIF11, BUB1, and DLGAP5, were identified, shedding light on their pivotal roles in cell cycle regulation. The study also identified miRNAs (e.g., hsa-mir-7-5p and hsa-mir-138-5p) and transcription factors (e.g., E2F1 and TP53) associated with ACC. Drug-gene interactions have identified potential therapeutic options, including amsacrine and rucaparib. Conclusions The ACC gene expression highlights a nuanced molecular landscape, identifying pivotal hub genes such as KIF11 and CDK1 as potential therapeutic targets for ACC, given their roles in cell cycle progression. The dysregulation of microRNAs and transcription factors adds complexity to ACC's molecular profile. Exploration of drug-gene interactions reveals promising therapeutic strategies, involving FDA-approved drugs such as amsacrine and rucaparib, providing avenues for personalized interventions.

Direct Amination of α-Triaryl Alcohols via Vanadium Catalysis

α-Triaryl amines have been used as pharmaceuticals and pharmaceutical intermediates for antifungal and anticancer applications. Current methods to synthesize such compounds require at least two steps, and no direct amination of tertiary alcohols has been reported. Herein, we disclose efficient catalytic conditions for the direct amination of α-triaryl alcohols to access α-triaryl amines. VO(OⁱPr)₃, a commercially available reagent, has been identified as an effective catalyst for the direct amination of several α-triaryl alcohols. This process is scalable, as demonstrated by a gram-scale synthesis, and the reaction still works at as low as a 0.01 mol % catalyst loading with the turnover number reaching 3900. Moreover, commercial pharmaceuticals including clotrimazole and flutrimazole have been successfully prepared rapidly and efficiently using this newly developed method.

Half-Sandwich Ruthenium Arene Complexes Bearing Clinically Approved Drugs as Ligands: The Importance of Metal-Drug Synergism in Metallodrug Design

A novel strategy in metallodrug discovery today is incorporating clinically approved drugs into metal complexes as coordinating ligands. Using this strategy, various drugs have been repurposed to prepare organometallic complexes to overcome the resistance of drugs and to design promising alternatives to currently available metal-based drugs. Notably, the combination of organoruthenium moiety and clinical drug in a single molecule has been shown, in some instances, to enhance pharmacological activity and reduce toxicity in comparison to the parent drug. Thus, for the past two decades, there has been increasing interest in exploiting metal-drug synergism to develop multifunctional organoruthenium drug candidates. Herein, we summarized the recent reports of rationally designed half-sandwich Ru(arene) complexes containing different FDA-approved drugs. This review also focuses on the mode of coordination of drugs, ligand-exchange kinetics, mechanism of action, and structure-activity relationship of organoruthenated complexes containing drugs. We hope this discussion may serve to shed light on future developments in ruthenium-based metallopharmaceuticals.

Detachment of Hexokinase II From Mitochondria Promotes Collateral Sensitivity in Multidrug Resistant Chronic Myeloid Leukemia Cells

Chronic Myeloid Leukemia is a neoplastic disease characterized by the abnormal expansion of hematopoietic cells with compromised functions. Leukemic cells often display a multidrug resistance phenotype, enabling them to evade a number of structurally unrelated cytotoxic compounds. One of those mechanisms relies on the high expression of efflux transporters, such as the ABC proteins, whose activity depends on the hydrolysis of ATP to reduce intracellular drug accumulation. In the present work, we employed a well-known erythroleukemia cell line, K562, and a multidrug resistant derivative cell, FEPS, to evaluate how hexokinase II, a key regulator for the rate-limiting step glycolysis, contributes to the establishment of the multidrug resistance phenotype. We found that multidrug resistant cells primarily resort to glycolysis to generate ATP. Clotrimazole reduced the expression of mitochondrial hexokinase II, which destabilized bioenergetic parameters such as reactive oxygen species production, ATP, and glutathione levels on multidrug resistant cells. This impaired the activity of ABCC1, leading to increased drug accumulation and cell death. In summary, we propose that decoupling of hexokinase II from the mitochondria emerges as a promising strategy to generate collateral sensitivity and aid in the management of chronic myeloid leukemia in chemotherapy-refractory patients.

Clotrimazole Inhibits HCC Migration and Invasion by Modulating the ERK-p65 Signaling Pathway

Purpose

Hepatocellular carcinoma (HCC), has a very high mortality rate and is the most common type of liver cancer. Clotrimazole, a traditional antifungal drug, has garnered considerable attention as a therapeutic strategy for HCC. However, its effects against the migration and invasion of HCC cells as well as the associated underlying mechanisms remain unclear. Therefore, in this study, we investigated its effects on HCC and attempted to elucidate the underlying molecular mechanisms.

Methods

CCK-8 was used to investigate the inhibitory effect of clotrimazole on the proliferation of different types of HCC cells, and wound healing and transwell assays were performed to investigate its inhibitory effect on the invasion and migration of the HCC cells. Further, western blotting was employed to detect changes in the expression levels of epithelial mesenchymal transition (EMT)-related proteins, extracellular-regulated protein kinases (ERK), p-ERK, p65, and p-p65. We also used ERK activators in combination with clotrimazole to treat the HCC cell lines.

Results

Clotrimazole inhibited the invasion and migration of HCC cells, and mechanistically, it exerted these anti-tumor effects via EMT by repressing ERK phosphorylation.

Conclusion

These findings suggest that clotrimazole inhibits HCC metastasis by repressing EMT in an ERK dephosphorylation-dependent manner.

Large-scale and high-resolution mass spectrometry-based proteomics profiling defines molecular subtypes of esophageal cancer for therapeutic targeting

Esophageal cancer (EC) is a type of aggressive cancer without clinically relevant molecular subtypes, hindering the development of effective strategies for treatment. To define molecular subtypes of EC, we perform mass spectrometry-based proteomic and phosphoproteomics profiling of EC tumors and adjacent non-tumor tissues, revealing a catalog of proteins and phosphosites that are dysregulated in ECs. The EC cohort is stratified into two molecular subtypes-S1 and S2-based on proteomic analysis, with the S2 subtype characterized by the upregulation of spliceosomal and ribosomal proteins, and being more aggressive. Moreover, we identify a subtype signature composed of ELOA and SCAF4, and construct a subtype diagnostic and prognostic model. Potential drugs are predicted for treating patients of S2 subtype, and three candidate drugs are validated to inhibit EC. Taken together, our proteomic analysis define molecular subtypes of EC, thus providing a potential therapeutic outlook for improving disease outcomes in patients with EC.

Repurposing of Antimicrobial Agents for Cancer Therapy: What Do We Know?

The substantial costs of clinical trials, the lengthy timelines of new drug discovery and development, along the high attrition rates underscore the need for alternative strategies for finding quickly suitable therapeutics agents. Given that most approved drugs possess more than one target tightly linked to other diseases, it encourages promptly testing these drugs in patients. Over the past decades, this has led to considerable attention for drug repurposing, which relies on identifying new uses for approved or investigational drugs outside the scope of the original medical indication. The known safety of approved drugs minimizes the possibility of failure for adverse toxicology, making them attractive de-risked compounds for new applications with potentially lower overall development costs and shorter development timelines. This latter case is an exciting opportunity, specifically in oncology, due to increased resistance towards the current therapies. Indeed, a large body of evidence shows that a wealth of non-cancer drugs has beneficial effects against cancer. Interestingly, 335 drugs are currently being evaluated in different clinical trials for their potential activities against various cancers (Redo database). This review aims to provide an extensive discussion about the anti-cancer activities exerted by antimicrobial agents and presents information about their mechanism(s) of action and stage of development/evaluation.

Novel Strategies for Disrupting Cancer-Cell Functions with Mitochondria-Targeted Antitumor Drug-Loaded Nanoformulations

Any variation in normal cellular function results in mitochondrial dysregulation that occurs in several diseases, including cancer. Such processes as oxidative stress, metabolism, signaling, and biogenesis play significant roles in cancer initiation and progression. Due to their central role in cellular metabolism, mitochondria are favorable therapeutic targets for the prevention and treatment of conditions like neurodegenerative diseases, diabetes, and cancer. Subcellular mitochondria-specific theranostic nanoformulations for simultaneous targeting, drug delivery, and imaging of these organelles are of immense interest in cancer therapy. It is a challenging task to cross multiple barriers to target mitochondria in diseased cells. To overcome these multiple barriers, several mitochondriotropic nanoformulations have been engineered for the transportation of mitochondria-specific drugs. These nanoformulations include liposomes, dendrimers, carbon nanotubes, polymeric nanoparticles (NPs), and inorganic NPs. These nanoformulations are made mitochondriotropic by conjugating them with moieties like dequalinium, Mito-Porter, triphenylphosphonium, and Mitochondria-penetrating peptides. Most of these nanoformulations are meticulously tailored to control their size, charge, shape, mitochondriotropic drug loading, and specific cell-membrane interactions. Recently, some novel mitochondria-selective antitumor compounds known as mitocans have shown high toxicity against cancer cells. These selective compounds form vicious oxidative stress and reactive oxygen species cycles within cancer cells and ultimately push them to cell death. Nanoformulations approved by the FDA and EMA for clinical applications in cancer patients include Doxil, NK105, and Abraxane. The novel use of these NPs still faces tremendous challenges and an immense amount of research is needed to understand the proper mechanisms of cancer progression and control by these NPs. Here in this review, we summarize current advancements and novel strategies of delivering different anticancer therapeutic agents to mitochondria with the help of various nanoformulations.

Achievements in Thermosensitive Gelling Systems for Rectal Administration

Rectal drug delivery is an effective alternative to oral and parenteral treatments. This route allows for both local and systemic drug therapy. Traditional rectal dosage formulations have historically been used for localised treatments, including laxatives, hemorrhoid therapy and antipyretics. However, this form of drug dosage often feels alien and uncomfortable to a patient, encouraging refusal. The limitations of conventional solid suppositories can be overcome by creating a thermosensitive liquid suppository. Unfortunately, there are currently only a few studies describing their use in therapy. However, recent trends indicate an increase in the development of this modern therapeutic system. This review introduces a novel rectal drug delivery system with the goal of summarising recent developments in thermosensitive liquid suppositories for analgesic, anticancer, antiemetic, antihypertensive, psychiatric, antiallergic, anaesthetic, antimalarial drugs and insulin. The report also presents the impact of various types of components and their concentration on the properties of this rectal dosage form. Further research into such formulations is certainly needed in order to meet the high demand for modern, efficient rectal gelling systems. Continued research and development in this field would undoubtedly further reveal the hidden potential of rectal drug delivery systems.

Modulation of lactate-lysosome axis in dendritic cells by clotrimazole potentiates antitumor immunity

BACKGROUND

Dendritic cells (DCs) play a critical role in antitumor immunity, but the therapeutic efficacy of DC-mediated cancer vaccine remains low, partly due to unsustainable DC function in tumor antigen presentation. Thus, identifying drugs that could enhance DC-based antitumor immunity and uncovering the underlying mechanism may provide new therapeutic options for cancer immunotherapy.

METHODS

In vitro antigen presentation assay was used for DC-modulating drug screening. The function of DC and T cells was measured by flow cytometry, ELISA, or qPCR. B16, MC38, CT26 tumor models and C57BL/6, Balb/c, nude, and Batf3-/- mice were used to analyze the in vivo therapy efficacy and impact on tumor immune microenvironment by clotrimazole treatment.

RESULTS

By screening a group of small molecule inhibitors and the US Food and Drug Administration (FDA)-approved drugs, we identified that clotrimazole, an antifungal drug, could promote DC-mediated antigen presentation and enhance T cell response. Mechanistically, clotrimazole acted on hexokinase 2 to regulate lactate metabolic production and enhanced the lysosome pathway and Chop expression in DCs subsequently induced DC maturation and T cell activation. Importantly, in vivo clotrimazole administration induced intratumor immune infiltration and inhibited tumor growth depending on both DCs and CD8+ T cells and potentiated the antitumor efficacy of anti-PD1 antibody.

CONCLUSIONS

Our findings showed that clotrimazole could trigger DC activation via the lactate-lysosome axis to promote antigen cross-presentation and could be used as a potential combination therapy approach to improving the therapeutic efficacy of anti-PD1 immunotherapy.

Protein aggregation and the evolution of stress resistance in clinical yeast

Protein aggregation, particularly in its prion-like form, has long been thought to be detrimental. However, recent studies have identified multiple instances where protein aggregation is important for normal physiological functions. Combining mass spectrometry and cell biological approaches, we developed a strategy for the identification of protein aggregates in cell lysates. We used this approach to characterize prion-based traits in pathogenic strains of the yeast Saccharomyces cerevisiae isolated from immunocompromised human patients. The proteins that we found, including the metabolic enzyme Cdc19, the translation elongation factor Yef3 and the fibrillarin homologue Nop1, are known to assemble under certain physiological conditions. Yet, such assemblies have not been reported to be stable or heritable. Our data suggest that some proteins which aggregate in response to stress have the capacity to acquire diverse assembled states, certain ones of which can be propagated across generations in a form of protein-based epigenetics. This article is part of the theme issue 'How does epigenetics influence the course of evolution?'

A New Anti-Estrogen Discovery Platform Identifies FDA-Approved Imidazole Anti-Fungal Drugs as Bioactive Compounds against ERα Expressing Breast Cancer Cells

17β-estradiol (E2) exerts its physiological effects through the estrogen receptor α (i.e., ERα). The E2:ERα signaling allows the regulation of cell proliferation. Indeed, E2 sustains the progression of ERα positive (ERα+) breast cancers (BCs). The presence of ERα at the BC diagnosis drives their therapeutic treatment with the endocrine therapy (ET), which restrains BC progression. Nonetheless, many patients develop metastatic BCs (MBC) for which a treatment is not available. Consequently, the actual challenge is to complement the drugs available to fight ERα+ primary and MBC. Here we exploited a novel anti-estrogen discovery platform to identify new Food and Drug Administration (FDA)-approved drugs inhibiting E2:ERα signaling to cell proliferation in cellular models of primary and MBC cells. We report that the anti-fungal drugs clotrimazole (Clo) and fenticonazole (Fenti) induce ERα degradation and prevent ERα transcriptional signaling and proliferation in cells modeling primary and metastatic BC. The anti-proliferative effects of Clo and Fenti occur also in 3D cancer models (i.e., tumor spheroids) and in a synergic manner with the CDK4/CDK6 inhibitors palbociclib and abemaciclib. Therefore, Clo and Fenti behave as “anti-estrogens”-like drugs. Remarkably, the present “anti-estrogen” discovery platform represents a valuable method to rapidly identify bioactive compounds with anti-estrogenic activity.

Exploiting Mitochondrial Vulnerabilities to Trigger Apoptosis Selectively in Cancer Cells

The transformation of normal cells to the cancerous stage involves multiple genetic changes or mutations leading to hyperproliferation, resistance to apoptosis, and evasion of the host immune system. However, to accomplish hyperproliferation, cancer cells undergo profound metabolic reprogramming including oxidative glycolysis and acidification of the cytoplasm, leading to hyperpolarization of the mitochondrial membrane. The majority of drug development research in the past has focused on targeting DNA replication, repair, and tubulin polymerization to induce apoptosis in cancer cells. Unfortunately, these are not cancer-selective targets. Recently, researchers have started focusing on metabolic, mitochondrial, and oxidative stress vulnerabilities of cancer cells that can be exploited as selective targets for inducing cancer cell death. Indeed, the hyperpolarization of mitochondrial membranes in cancer cells can lead to selective importing of mitocans that can induce apoptotic effects. Herein, we will discuss recent mitochondrial-selective anticancer compounds (mitocans) that have shown selective toxicity against cancer cells. Increased oxidative stress has also been shown to be very effective in selectively inducing cell death in cancer cells. This oxidative stress could lead to mitochondrial dysfunction, which in turn will produce more reactive oxygen species (ROS). This creates a vicious cycle of mitochondrial dysfunction and ROS production, irreversibly leading to cell suicide. We will also explore the possibility of combining these compounds to sensitize cancer cells to the conventional anticancer agents. Mitocans in combination with selective oxidative-stress producing agents could be very effective anticancer treatments with minimal effect on healthy cells.

Development of a Method for the Quantification of Clotrimazole and Itraconazole and Study of Their Stability in a New Microemulsion for the Treatment of Sporotrichosis

Sporotrichosis occurs worldwide and is caused by the fungus Sporothrix brasiliensis. This agent has a high zoonotic potential and is transmitted mainly by bites and scratches from infected felines. A new association between the drugs clotrimazole and itraconazole is shown to be effective against S. brasiliensis yeasts. This association was formulated as a microemulsion containing benzyl alcohol as oil, Tween^® 60 and propylene glycol as surfactant and cosurfactant, respectively, and water. Initially, the compatibility between clotrimazole and itraconazole was studied using differential scanning calorimetry (DSC), thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR), and X-ray powder diffraction (PXRD). Additionally, a simple and efficient analytical HPLC method was developed to simultaneously determine the concentration of clotrimazole and itraconazole in the novel microemulsion. The developed method proved to be efficient, robust, and reproducible for both components of the microemulsion. We also performed an accelerated stability study of this formulation, and the developed analytical method was applied to monitor the content of active ingredients. Interestingly, these investigations led to the detection of a known clotrimazole degradation product whose structure was confirmed using NMR and HRMS, as well as a possible interaction between itraconazole and benzyl alcohol.

Identification of FDA-Approved Drugs with Activity against Stationary Phase Bartonella henselae

Bartonella henselae can cause various infections in humans, ranging from benign and self-limiting diseases to severe and life-threatening diseases as well as persistent infections that are difficult to treat. To develop more effective treatments for persistent Bartonella infections, in this study, we performed a high-throughput screen of an FDA-approved drug library against stationary phase B. henselae using the SYBR Green I/propidium iodide (PI) viability assay. We identified 110 drug candidates that had better activity against stationary phase B. henselae than ciprofloxacin, and among the top 52 drug candidates tested, 41 drugs were confirmed by microscopy to have higher activity than the current frontline antibiotic erythromycin. The identified top drug candidates include pyrvinium pamoate, daptomycin, methylene blue, azole drugs (clotrimazole, miconazole, sulconazole, econazole, oxiconazole, butoconazole, bifonazole), aminoglycosides (gentamicin and streptomycin, amikacin, kanamycin), amifostine (Ethyol), antiviral Lopinavir/ritonavir, colistin, nitroxoline, nitrofurantoin, verteporfin, pentamidine, berberine, aprepitant, olsalazine, clinafloxacin, and clofoctol. Pyrvinium pamoate, daptomycin, methylene blue, clotrimazole, and gentamicin and streptomycin at their respective maximum drug concentration in serum (C_max) had the capacity to completely eradicate stationary phase B. henselae after 3-day drug exposure in subculture studies. While the currently used drugs for treating bartonellosis, including rifampin, erythromycin, azithromycin, doxycycline, and ciprofloxacin, had very low minimal inhibitory concentration (MIC) against growing B. henselae, they had relatively poor activity against stationary phase B. henselae, except aminoglycosides. The identified FDA-approved agents with activity against stationary phase B. henselae should facilitate development of more effective treatments for persistent Bartonella infections.

Targeting mitochondrial hexokinases increases efficacy of histone deacetylase inhibitors in solid tumor models

Hexokinase 1 and 2 have been shown to inhibit Bak- and Bax-mediated apoptosis, leading us to combine the histone deacetylase inhibitor romidepsin with clotrimazole or bifonazole, two compounds that reportedly decrease mitochondrial localization of hexokinases. Cancer cell lines derived from breast, kidney, lung, colon or ovarian cancers were treated with a short-term exposure to 25 ng/ml romidepsin combined with either clotrimazole or bifonazole. The combination of romidepsin with 25 µM clotrimazole or bifonazole resulted in increased annexin staining compared to cells treated with any of the drugs alone. Cell death was caspase-mediated, as the pan-caspase inhibitor Q-VD-OPh was found to inhibit apoptosis induced by the combination. A549 lung cancer cells or HCT-116 cells deficient in Bak and Bax were also resistant to apoptosis with the combination implicating the intrinsic apoptotic pathway. We found that a 24 h treatment with clotrimazole or bifonazole decreased total hexokinase 2 expression, resulting in a 76% or 60% decrease, respectively, of mitochondrial expression of hexokinase 2. Mitochondrial hexokinase 1 levels increased 2-fold or less. Our work suggests that the combination of a short-term romidepsin treatment with bifonazole or clotrimazole leads to increased apoptosis, most likely due to decreased mitochondrial expression of hexokinase 2.

Imidazole Antifungal Drugs Inhibit the Cell Proliferation and Invasion of Human Breast Cancer Cells

Breast cancer is currently the most prevalent cancer in women, and its incidence increases every year. Azole antifungal drugs were recently found to have antitumor efficacy in several cancer types. They contain an imidazole (clotrimazole and ketoconazole) or a triazole (fluconazole and itraconazole) ring. Using human breast adenocarcinoma cells (MCF-7 and MDA-MB-231), we evaluated the effects of azole drugs on cell proliferation, apoptosis, cell cycle, migration, and invasion, and investigated the underlying mechanisms. Clotrimazole and ketoconazole inhibited the proliferation of both cell lines while fluconazole and itraconazole did not. In addition, clotrimazole and ketoconazole inhibited the motility of MDA-MB-231 cells and induced G₁-phase arrest in MCF-7 and MDA-MB-231 cells, as determined by cell cycle analysis and immunoblot data. Moreover, Transwell invasion and gelatin zymography assays revealed that clotrimazole and ketoconazole suppressed invasiveness through the inhibition of matrix metalloproteinase 9 in MDA-MB-231 cells, although no significant changes in invasiveness were observed in MCF-7 cells. There were no significant changes in any of the observed parameters with fluconazole or itraconazole treatment in either breast cancer cell line. Taken together, imidazole antifungal drugs showed strong antitumor activity in breast cancer cells through induction of apoptosis and G₁ arrest in both MCF-7 and MDA-MB-231 cells and suppression of invasiveness via matrix metalloproteinase 9 inhibition in MDA-MB-231 cells. Imidazole drugs have well-established pharmacokinetic profiles and known toxicity, which can make these generic drugs strong candidates for repositioning as antitumor therapies.

VDAC1 as Pharmacological Target in Cancer and Neurodegeneration: Focus on Its Role in Apoptosis

Cancer and neurodegeneration are different classes of diseases that share the involvement of mitochondria in their pathogenesis. Whereas the high glycolytic rate (the so-called Warburg metabolism) and the suppression of apoptosis are key elements for the establishment and maintenance of cancer cells, mitochondrial dysfunction and increased cell death mark neurodegeneration. As a main actor in the regulation of cell metabolism and apoptosis, VDAC may represent the common point between these two broad families of pathologies. Located in the outer mitochondrial membrane, VDAC forms channels that control the flux of ions and metabolites across the mitochondrion thus mediating the organelle's cross-talk with the rest of the cell. Furthermore, the interaction with both pro-apoptotic and anti-apoptotic factors makes VDAC a gatekeeper for mitochondria-mediated cell death and survival signaling pathways. Unfortunately, the lack of an evident druggability of this protein, since it has no defined binding or active sites, makes the quest for VDAC interacting molecules a difficult tale. Pharmacologically active molecules of different classes have been proposed to hit cancer and neurodegeneration. In this work, we provide an exhaustive and detailed survey of all the molecules, peptides, and microRNAs that exploit VDAC in the treatment of the two examined classes of pathologies. The mechanism of action and the potential or effectiveness of each compound are discussed.

Clotrimazole is highly effective in vitro against feline Sporothrix brasiliensis isolates

PURPOSE

Sporothrix brasiliensis, the most virulent species in the Sporothrix schenckii complex, is responsible for the ongoing epidemics of human and animal sporotrichosis in Brazil. Feline outbreaks are usually driven by S. brasiliensis and followed by extensive transmission to humans. Itraconazole is the first-line treatment for both feline and human sporotrichosis; however, reduced sensitivity is an emerging issue. Thus, we investigated the effect of the widely used antifungal clotrimazole - alone or in combination with itraconazole - against the pathogenic (yeast) form of feline and human S. brasiliensis isolates, in vitro.

METHODOLOGY

Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values were determined for treatment with clotrimazole and itraconazole, as monotherapy or in combination. In addition, the effect of the drugs on neutral lipid levels and the yeast ultrastructure were evaluated by flow cytometry and transmission electron microscopy (TEM), respectively.

RESULTS

The MIC and MFC values show that clotrimazole was more effective than itraconazole against feline S. brasiliensis isolates, while human isolates were more sensitive to itraconazole. Similarly to itraconazole, treatment with clotrimazole induced statistically significant neutral lipid accumulation in S. brasiliensis yeasts, and treated yeasts displayed irregularities in the cell membrane and a thicker cell wall when observed by TEM. Clotrimazole increased the antifungal activity of itraconazole in combination assays, with a synergistic effect for two feline isolates.

CONCLUSION

The strong activity of clotrimazole against feline S. brasiliensis isolates suggests that this drug is potentially a new alternative for the treatment of feline sporotrichosis, alone or in combination with itraconazole.

A structure- and chemical genomics-based approach for repositioning of drugs against VCP/p97 ATPase

Valosin-containing protein (VCP/p97) ATPase (a.k.a. Cdc48) is a key member of the ER-associated protein degradation (ERAD) pathway. ERAD and VCP/p97 have been implicated in a multitude of human diseases, such as neurodegenerative diseases and cancer. Inhibition of VCP/p97 induces proteotoxic ER stress and cell death in cancer cells, making it an attractive target for cancer treatment. However, no drugs exist against this protein in the market. Repositioning of drugs towards new indications is an attractive alternative to the de novo drug development due to the potential for significantly shorter time to clinical translation. Here, we employed an integrative strategy for the repositioning of drugs as novel inhibitors of the VCP/p97 ATPase. We integrated structure-based virtual screening with the chemical genomics analysis of drug molecular signatures, and identified several candidate inhibitors of VCP/p97 ATPase. Importantly, experimental validation with cell-based and in vitro ATPase assays confirmed three (ebastine, astemizole and clotrimazole) out of seven tested candidates (~40% true hit rate) as direct inhibitors of VCP/p97 and ERAD. This study introduces an effective integrative strategy for drug repositioning, and identified new drugs against the VCP/p97/ERAD pathway in human diseases.