Repurposed drug battles 'brain-eating' amoeba.

A drug for urinary tract infections may also treat Balamuthia mandrillaris.

Discovery and Validation of Nitroxoline as a Novel STAT3 Inhibitor in Drug-resistant Urothelial Bladder Cancer.

Repeated cycles of first-line chemotherapy drugs such as doxorubicin (DOX) and cisplatin (CIS) trigger frequent chemoresistance in recurrent urothelial bladder cancer (UBC). Nitroxoline (NTX), an antibiotic to treat urinary tract infections, has been recently repurposed for cancer treatment. Here we aimed to investigate whether NTX suppresses drug-resistant UBC and its molecular mechanism. The drug-resistant cell lines T24/DOX and T24/CIS were established by continual exposure of parental cell line T24 to DOX and CIS, respectively. T24/DOX and T24/CIS cells were resistant to DOX and CIS, respectively, but they were sensitive to NTX time- and dose-dependently. Overexpressions of STAT3 and P-glycoprotein (P-gp) were identified in T24/DOX and T24/CIS, which could be reversed by NTX. Western blot revealed that NTX downregulated p-STAT3, c-Myc, Cyclin D1, CDK4, CDK6, Bcl-xL, Mcl-1, and Survivin, which were further confirmed by Stattic, a selective STAT3 inhibitor. In vivo, NTX exhibited the significant anti-tumor effect in T24/DOX and T24/CIS tumor-bearing mice. These results suggested that NTX-induced P-gp reversal, G0/G1 arrest, and apoptosis in drug-resistant UBC were mediated by inhibition of STAT3 signaling. Our findings repurpose NTX as a novel STAT3 inhibitor to induce P-gp reversal, G0/G1 arrest, and apoptosis in drug-resistant UBC.

Nitroxoline: repurposing its antimicrobial to antitumor application.

Cancer is a disease receiving an outstanding input of funds for basic and clinical research but is, nevertheless, still the second leading cause of death in the developed world and a great burden for health systems. New drugs are therefore needed to improve therapy, prolong survival of cancer patients and improve their quality of life. The high cost of development and clinical evaluation of new drugs limits the number that actually enter clinical use. To overcome this problem, repurposing of established drugs for new indications has gained a lot of interest, especially in the field of oncology. The well-established antimicrobial agent nitroxoline has been identified as a promising candidate to be repurposed for cancer treatment in several independent studies. Here we have reviewed a wide range of molecular mechanisms and tumor models involving nitroxoline in impairment of tumor progression. Furthermore, nitroxoline was used as a lead compound for structure-based chemical synthesis of new derivatives in order to improve its potency as well as selectivity for various targets. The potent antitumor activity of nitroxoline points strongly in the direction of its repurposing for cancer treatment and to the benefits of this strategy for patients and healthcare system.

Decreased APE-1 by Nitroxoline Enhances Therapeutic Effect in a Temozolomide-resistant Glioblastoma: Correlation with Diffusion Weighted Imaging.

Glioblastoma multiforme (GBM) is one of the most aggressive human tumors with poor survival rates. The current standard treatment includes chemotherapy with temozolomide (TMZ), but acquisition of resistance is a persistent clinical problem limiting the successful treatment of GBM. The purpose of our study was to investigate therapeutic effects of nitroxoline (NTX) against TMZ-resistant GBM in vitro and in vivo in TMZ-resistant GBM-bearing mouse model, which was correlated with diffusion-weighted imaging (DWI). For in vitro study, we used TMZ-resistant GBM cell lines and evaluated therapeutic effects of NTX by clonogenic and migration assays. Quantitative RT-PCR was used to investigate the expression level of TMZ-resistant genes after NTX treatment. For in vivo study, we performed 9.4 T MR imaging to obtain T2WI for tumor volume measurement and DWI for assessment of apparent diffusion coefficient (ADC) changes by NTX in TMZ-resistant GBM mice (n = 8). Moreover, we performed regression analysis for the relationship between ADC and histological findings, which reflects the changes in cellularity and apurinic/apyrimidinic endonuclease-1 (APE-1) expression. We observed the recovery of TMZ-induced morphological changes, a reduced number of colonies and a decreased rate of migration capacity in TMZ-resistant cells after NTX treatment. The expression of APE-1 was significantly decreased in TMZ-resistant cells after NTX treatment compared with those without treatment. In an in vivo study, NTX reduced tumor growth in TMZ-resistant GBM mice (P = 0.0122). Moreover, ADC was increased in the NTX-treated TMZ-resistant GBM mice compared to the control group (P = 0.0079), which was prior to a tumor volume decrease. The cellularity and APE-1 expression by histology were negatively correlated with the ADC value, which in turn resulted in longer survival in NTX group. The decreased expression of APE-1 by NTX leads to therapeutic effects and is inversely correlated with ADC in TMZ-resistant GBM. Therefore, NTX is suggested as potential therapeutic candidate against TMZ-resistant GBM.

The Novel Combination of Nitroxoline and PD-1 Blockade, Exerts a Potent Antitumor Effect in a Mouse Model of Prostate Cancer.

Programmed cell death protein 1 (PD-1) blockade is a promising therapeutic strategy against prostate cancer. Nitroxoline has been found to have effective anticancer properties in several cancer types. We investigated the efficacy of a combination therapy involving nitroxoline and PD-1 blockade in a prostate cancer mouse model. In our in vitro analysis, we found that nitroxoline inhibited the viability and proliferation of the mouse prostate cancer cell line RM9-Luc-PSA. Additionally, nitroxoline downregulated the expressions of phospho-PI3 kinase, phospho-Akt (Thr308), phospho-Akt (Ser473), phospho-GSK-3ß, Bcl-2, and Bcl-xL. Nitroxoline also downregulated programmed death-ligand 1 (PD-L1) expression levels in prostate cancer cell line and tumor tissue. In our murine prostate cancer orthotopic model, nitroxoline plus PD-1 blockade synergistically suppressed tumor growth when compared with nitroxoline or PD-1 blockade alone, leading to reductions in tumor weight, bioluminescence tumor signals, and serum prostate-specific antigen levels. Furthermore, fluorescence-activated cell sorting analysis showed that the combination strategy significantly enhanced antitumor immunity by increasing CD44+CD62L+CD8+ memory T cell numbers and reducing myeloid-derived suppressor cell numbers in peripheral blood. In conclusion, our findings suggest that nitroxoline plus PD-1 blockade may be a promising treatment strategy in patients with prostate cancer.

Nitroxoline: an option for the treatment of urinary tract infection with multi-resistant uropathogenic bacteria.

The number of multi-resistant uropathogens is increasing. A multi-morbid patient developed a symptomatic urinary tract infection with two multi-resistant bacteria, namely Klebsiella pneumoniae and Proteus mirabilis. Nitroxoline was the only drug active against both uropathogens. Obviously, nitroxoline can be an option for the therapy of a urinary tract infection with multi-resistant uropathogens.

Review of the pharmacokinetic properties of nitrofurantoin and nitroxoline.

Nitrofurantoin and nitroxoline are oral antibiotics for the treatment or prophylaxis of acute urinary tract infections. New interest in both these drugs is increasing because of the emergence of resistance to other antibiotics, but knowledge of their pharmacokinetics (PK) is lacking since they were developed before the advent of standardized research for drug approval. The aims of this review were to (i) summarize the PK data reported in the literature and (ii) to identify PK knowledge gaps. The current body of PK knowledge of both drugs appears to be poor and mainly based on old studies. Nitrofurantoin PK values were obtained from studies using many variables, e.g. formulations, crystal sizes and analytical methods, resulting in high interindividual variability in PK parameters and no uniform PK profile. Clinical experience and PK data for nitroxoline are even more limited since the drug is registered in only Germany and a few (Eastern European) countries. Clinical studies in relevant patient populations are needed with commercially available nitrofurantoin and nitroxoline formulations at approved dosing regimens to more fully characterize their PK profiles, and to investigate the influence of patient characteristics on these profiles in order to optimize efficacy and avoid toxicity and emergence of resistance. Only with this updated knowledge and efficacy data from well-structured trials can both drugs maintain their antimicrobial activity against uropathogens.

Susceptibility of Escherichia coli to nitroxoline, an option for uncomplicated urinary tract infections - the first report from Croatia.

Nitroxoline (NTX), 5-nitro-8-hydroxyquinoline is an oral antibiotic with mechanism of bacteriostatic activity that is based on chelation of divalent cations required for bacterial RNA polymerase. Susceptibility to NTX of 100 Escherichia coli urine isolates was determined at the Department of Clinical and Molecular Microbiology, University Hospital Centre Zagreb during September and October 2017. Antimicrobial susceptibility was tested by disc diffusion and the results were interpreted according to the European Committee for Antimicrobial Susceptibility Testing (EUCAST) standards. All E. coli isolates, including ESBL-positive ones, were fully susceptible to imipenem, meropenem, amikacin, fosfomycin and NTX. This is the first report from Croatia about sensitivity of E. coli isolates to NTX. Besides fosfomycin, NTX was the only antimicrobial drug available for peroral administration demonstrating the sensitivity for all tested isolates. The results of the study demonstrated the potential of NTX as an additional therapeutically applicable option for the treatment of uncomplicated UTI.

Structure-based development of nitroxoline derivatives as potential multifunctional anti-Alzheimer agents.

Tremendous efforts have been dedicated to the development of effective therapeutics against Alzheimer's disease, which represents the most common debilitating neurodegenerative disease. Multifunctional agents are molecules designed to have simultaneous effects on different pathological processes. Such compounds represent an emerging strategy for the development of effective treatments against Alzheimer's disease. Here, we report on the synthesis and biological evaluation of a series of nitroxoline-based analogs that were designed by merging the scaffold of 8-hydroxyquinoline with that of a known selective butyrylcholinesterase inhibitor that has promising anti-Alzheimer properties. Most strikingly, compound 8g inhibits self-induced aggregation of the amyloid beta peptide (Aß1-42), inhibits with sub-micromolar potency butyrylcholinesterase (IC50=215 nM), and also selectively complexes Cu(2+). Our study thus designates this compound as a promising multifunctional agent for therapeutic treatment of Alzheimer's disease. The crystal structure of human butyrylcholinesterase in complex with compound 8g is also solved, which suggests ways to further optimize compounds featuring the 8-hydroxyquinoline scaffold.

Nitroxoline induces apoptosis and slows glioma growth in vivo.

BACKGROUND: Nitroxoline is an FDA-approved antibiotic with potential antitumor activity. Here we evaluated whether nitroxoline has antiproliferative properties on glioma cell growth in vitro and in vivo using glioma cell lines and a genetically engineered PTEN/KRAS mouse glioma model. METHODS: The effect of nitroxoline treatment on U87 and/or U251 glioma cell proliferation, cell-cycle arrest, invasion, and ability to induce an apoptotic cascade was determined in vitro. Magnetic resonance imaging was used to measure glioma volumes in genetically engineered PTEN/KRAS mice prior to and after nitroxoline therapy. Induction of apoptosis by nitroxoline was evaluated at the end of treatment using terminal deoxyribonucleotidyl transferase (TDT)-mediated dUTP-digoxigenin nick end labeling (TUNEL). RESULTS: Nitroxoline inhibited the proliferation and invasion of glioblastoma cells in a time- and dose-dependent manner in vitro. Growth inhibition was associated with cell-cycle arrest in G1/G0 phase and induction of apoptosis via caspase 3 and cleaved poly(ADP-ribose) polymerase. In vivo, nitroxoline-treated mice had no increase in tumor volume after 14 days of treatment, whereas tumor volumes doubled in control mice. Histological examination revealed 15%-20% TUNEL-positive cells in nitroxoline-treated mice, compared with ∼5% in the control group. CONCLUSION: Nitroxoline induces apoptosis and inhibits glioma growth in vivo and in vitro. As an already FDA-approved treatment for urinary tract infections with a known safety profile, nitroxoline could move quickly into clinical trials pending confirmatory studies.

Review of the literature and individual patients' data meta-analysis on efficacy and tolerance of nitroxoline in the treatment of uncomplicated urinary tract infections.

BACKGROUND: Nitroxoline, a hydroxychinoline derivate, has been used for many years to treat urinary tract infections (UTI). Many uncontrolled, but only few controlled clinical studies have been published. Four so far unpublished, controlled clinical studies were meta-analysed. METHODS: A narrative literature review was performed. In addition the individual patient data (IPD) of 466 females with uncomplicated UTI of four prospective, single blind, randomized, clinical studies with similar protocols using nitroxoline (250 mg tid) versus cotrimoxazole (960 mg bid) or norfloxacin (400 mg bid) as controls for 5 days (sporadic UTI) or 10 days (recurrent UTI) were meta-analysed. The primary aim was eradication of bacteriuria 7-13 days after end of therapy (test of cure). Clinical efficacy was determined by elimination of symptoms and safety by adverse events and laboratory tests. RESULTS: Reviewing a total of 26 uncontrolled, 2 controlled and one postmarketing studies including more than 11,000 patients, good efficacy and safety of nitroxoline could be confirmed. In the four unpublished controlled studies a total of 234 patients were treated orally with nitroxoline and 232 with controls. The safety of nitroxoline was very good and comparable to the controls (adverse events 9.4% vs 7.8%; p = 0.360). In the mMITT set (at least one outcome result), in the PP set (test of cure outcome) and in the modified PP set (missing test of cure rated failure) more than 90% of the patients showed eradication of bacteriuria with nitroxoline, which also met statistical non-inferiority compared to the controls (10% non-inferiority margin) in all three evaluation sets. The clinical efficacy was similar between the two treatment groups. CONCLUSION: The IPD meta-analysis using objective parameters (elimination of bacteriuria) demonstrated equivalent efficacy (non-inferiority) of nitroxoline with the controls tested (cotrimoxazole, norfloxacin) in the treatment of uncomplicated UTI. Considering the good safety and efficacy of nitroxoline as also shown in many uncontrolled and observational studies and the world wide increase of resistance of uropathogens against cotrimoxazole and fluoroquinolones, but not against nitroxoline within the last 20 years, nitroxoline should be reconsidered as one of the first line antibiotics for the treatment of uncomplicated UTI.

Recent advances in drug repositioning for the discovery of new anticancer drugs.

Drug repositioning (also referred to as drug repurposing), the process of finding new uses of existing drugs, has been gaining popularity in recent years. The availability of several established clinical drug libraries and rapid advances in disease biology, genomics and bioinformatics has accelerated the pace of both activity-based and in silico drug repositioning. Drug repositioning has attracted particular attention from the communities engaged in anticancer drug discovery due to the combination of great demand for new anticancer drugs and the availability of a wide variety of cell- and target-based screening assays. With the successful clinical introduction of a number of non-cancer drugs for cancer treatment, drug repositioning now became a powerful alternative strategy to discover and develop novel anticancer drug candidates from the existing drug space. In this review, recent successful examples of drug repositioning for anticancer drug discovery from non-cancer drugs will be discussed.

New directions for neurodegenerative disease therapy: using chemical compounds to boost the formation of mutant protein inclusions.

Neurodegenerative diseases such as Huntington's, Parkinson's and Alzheimer's diseases are marked by neuronal accumulation of toxic misfolded protein. Developing therapies for these misfolding diseases requires finding chemical compounds that can either clear toxic misfolded protein, or can protect neurons from their impact. Such compounds could not only provide the starting points for potential drugs, but could also provide valuable research tools for untangling the complexities of the disease process. Until now, chemical screens for these diseases have focused on finding compounds that prevent aggregation of mutant protein. We recently published a compound, B2, which promotes the formation of large inclusions by mutant Huntingtin and alpha-synuclein, while rescuing some of the toxic effects of these proteins. As inclusions were long believed to be toxic to cells, this contradicts previous therapeutic approaches. At the same time, the results support growing evidence for the protective effects of inclusions. In this review, we discuss these results, and place them in the context of ongoing therapeutic discovery efforts for Huntington's disease and other neurodegenerative diseases.

[Urinary tract infections in Dakar: etiologies, therapeutic basis]. / Infections du tractus urinaire à Dakar: etiologies, bases thérapeutiques.

This prospective study, performed in Fann University Teaching Hospital from January 1st to December 31st 1998, concern 1446 samples of urine. Enterobacteria (87.56%) were the most frequent aetiology, and Escherichia coli (48.7%) was the leading species in this family. The strains of E. coli present more resistant profil to beta-lactams (70.27%). Fluoroquinolons are active on more than 80% of the strains responsible of urinary tract infection in Dakar.

[Intensive combined therapy of patients with urogenital tuberculosis]. / Opyt intensifikatsii kombinirovannogo lecheniia bolnykh mochepolovym tuberkulezom.

More rapid attenuation of urogenital inflammation achieved in 41.65% of nephrophthiasis patients treated with combination levorin + furadonin + nitroxoline compared to control illustrates the validity of introducing tuberculostatic--potentiating drugs in chemotherapy of urogenital tuberculosis.

Effects of praziquantel and oxamniquine on a Saudi Arabian strain of Schistosoma mansoni in mice.

The prophylactic and curative effects of praziquantel and oxamniquine on a Saudi Arabian strain of Schistosoma mansoni in MF-1 mice were assessed. The drugs were administered orally. At 240 mg/kg praziquantel, there was a reduction of 89.1% in adult worm recovery and a marked reduction in tissue deposited eggs. The reduction in adult worm recovery after dosing with 50 mg/kg oxamniquine was 89.2%. At low doses (40 mg/kg praziquantel and 30 mg/kg oxamniquine) administered at 11 days, 5 days and 3 h before and 5, 21 and 49 days after infection, the reduction in adult worm recovery was 0.0%, 65.1%, 58.8%, 33.6%, 0.0% and 76.0% for praziquantel and 0.0%, 66.0%, 60.0%, 41.3%, 10.8% and 79.0% for oxamniquine. Numbers of lung schistosomula and the size of hepatic granulomata were also reduced.

Schistosoma mansoni: tegumental surface alterations following oxamniquine treatment of infected mice.

The in vivo effects of oxamniquine on the tegumental surface of adult Schistosoma mansoni were studied using scanning electron microscopy. Pronounced tegumental alterations were observed in all worms including marked oedema, wrinkling and distortion, atrophy, loss of tone and complete disorganization of suckers, blebbing, destruction of tubercles, collapse of sensory papillae and erosion or peeling of the surface layer. The amount of damage was more marked in males than females and varied considerably among worms recovered from the same host and even in different regions of the same worm. Damage was irreversible and all worms were eventually eliminated.