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International Journal of Molecular... Feb 2019Since none of the multidrug resistance (MDR) modulators tested so far found their way into clinic, a novel approach to overcome the MDR of cancer cells has been...
Since none of the multidrug resistance (MDR) modulators tested so far found their way into clinic, a novel approach to overcome the MDR of cancer cells has been proposed. The combined use of two MDR modulators of dissimilar mechanisms of action was suggested to benefit from the synergy between them. The effect of three phenothiazine derivatives that were used as single agents and in combination with simvastatin on cell growth, apoptosis induction, activity, and expression of cyclooxygenase-2 (COX-2) in doxorubicin-resistant colon cancer cells (LoVo/Dx) was investigated. Treatment of LoVo/Dx cells by phenothiazine derivatives combined with simvastatin resulted in an increase of doxorubicin cytotoxicity and its intracellular accumulation as compared to the treatment with phenothiazine derivatives that were used as single agents. Similarly, LoVo/Dx cells treated with two-component mixture of modulators showed the reduced expression of ABCB1 (P-glycoprotein) transporter and COX-2 enzyme, both on mRNA and protein level. Reduced expression of anti-apoptotic Bcl-2 protein and increased expression of pro-apoptotic Bax were also detected. Additionally, COX-2 activity was diminished, and caspase-3 activity was increased to a higher extent by phenothiazine derivative:simvastatin mixtures than by phenothiazine derivatives themselves. Therefore, the introduction of simvastatin strengthened the anti-MDR, anti-inflammatory, and pro-apoptotic properties of phenothiazines in LoVo/Dx cells.
Topics: ATP Binding Cassette Transporter, Subfamily B; Apoptosis; Caspase 3; Cell Line, Tumor; Colonic Neoplasms; Cyclooxygenase 2; Doxorubicin; Drug Resistance, Neoplasm; Drug Synergism; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Phenothiazines; Simvastatin; bcl-2-Associated X Protein
PubMed: 30813251
DOI: 10.3390/ijms20040955 -
Biomolecules Sep 2016There is a need to identify novel scaffolds and targets to develop new antibiotics. Methylene blue is a phenothiazine derivative, and it has been shown to possess...
There is a need to identify novel scaffolds and targets to develop new antibiotics. Methylene blue is a phenothiazine derivative, and it has been shown to possess anti-malarial and anti-trypanosomal activities. Here, we show that different phenothiazine derivatives and pyronine G inhibited the activities of three structurally different bacterial RNase P RNAs (RPRs), including that from Mycobacterium tuberculosis, with Ki values in the lower μM range. Interestingly, three antipsychotic phenothiazines (chlorpromazine, thioridazine, and trifluoperazine), which are known to have antibacterial activities, also inhibited the activity of bacterial RPRs, albeit with higher Ki values than methylene blue. Phenothiazines also affected lead(II)-induced cleavage of bacterial RPR and inhibited yeast tRNA(Phe), indicating binding of these drugs to functionally important regions. Collectively, our findings provide the first experimental data showing that long, noncoding RNAs could be targeted by different phenothiazine derivatives.
Topics: Anti-Bacterial Agents; Antipsychotic Agents; Bacterial Proteins; Lead; Phenothiazines; RNA, Bacterial; RNA, Fungal; RNA, Transfer; Ribonuclease P
PubMed: 27618117
DOI: 10.3390/biom6030038 -
Postgraduate Medical Journal Apr 1968
Review
Topics: Amphetamine; Antidepressive Agents; Barbiturates; Chlorpromazine; Hallucinogens; Haloperidol; Hypnotics and Sedatives; Imipramine; Lithium; Lysergic Acid Diethylamide; Monoamine Oxidase Inhibitors; Phenothiazines; Tranquilizing Agents
PubMed: 4870139
DOI: 10.1136/pgmj.44.510.286 -
Identification of phenothiazine derivatives as UHM-binding inhibitors of early spliceosome assembly.Nature Communications Nov 2020Interactions between U2AF homology motifs (UHMs) and U2AF ligand motifs (ULMs) play a crucial role in early spliceosome assembly in eukaryotic gene regulation. UHM-ULM...
Interactions between U2AF homology motifs (UHMs) and U2AF ligand motifs (ULMs) play a crucial role in early spliceosome assembly in eukaryotic gene regulation. UHM-ULM interactions mediate heterodimerization of the constitutive splicing factors U2AF65 and U2AF35 and between other splicing factors that regulate spliceosome assembly at the 3' splice site, where UHM domains of alternative splicing factors, such as SPF45 and PUF60, contribute to alternative splicing regulation. Here, we performed high-throughput screening using fluorescence polarization assays with hit validation by NMR and identified phenothiazines as general inhibitors of UHM-ULM interactions. NMR studies show that these compounds occupy the tryptophan binding pocket of UHM domains. Co-crystal structures of the inhibitors with the PUF60 UHM domain and medicinal chemistry provide structure-activity-relationships and reveal functional groups important for binding. These inhibitors inhibit early spliceosome assembly on pre-mRNA substrates in vitro. Our data show that spliceosome assembly can be inhibited by targeting UHM-ULM interactions by small molecules, thus extending the toolkit of splicing modulators for structural and biochemical studies of the spliceosome and splicing regulation.
Topics: Alternative Splicing; Humans; Phenothiazines; Protein Binding; Protein Domains; RNA Precursors; RNA Splicing Factors; Repressor Proteins; Spliceosomes; Splicing Factor U2AF
PubMed: 33159082
DOI: 10.1038/s41467-020-19514-1 -
Scientific Reports Jun 2023Assessing the in vitro toxicity of compounds on cell cultures is an important step during the screening of candidate molecules for diverse applications. Among the...
Assessing the in vitro toxicity of compounds on cell cultures is an important step during the screening of candidate molecules for diverse applications. Among the strategies employed to determine cytotoxicity, MTT, neutral red, and resazurin are commonly used. Methylene blue (MB), a phenothiazinium salt, has several uses, such as dye, redox indicator, and even as treatment for human disease and health conditions, such as malaria and methemoglobinemia. However, MB has only been sparsely used as a cellular toxicity indicator. As a viability indicator, MB is mostly applied to fixed cultures at high concentrations, especially when compared to MTT or neutral red. Here we show that MB and its related compounds new methylene blue (NMB), toluidine blue O (TBO), and dimethylmethylene blue (DMMB) can be used as cytotoxicity indicators in live (non-fixed) cells treated for 72 h with DMSO and cisplatin. We compared dye uptake between phenothiazinium dyes and neutral red by analyzing supernatant and cell content via visible spectra scanning and microscopy. All dyes showed a similar ability to assess cell toxicity compared to either MTT or neutral red. Our method represents a cost-effective alternative to in vitro cytotoxicity assays using cisplatin or DMSO, indicating the potential of phenothiazinium dyes for the screening of candidate drugs and other applications.
Topics: Humans; Coloring Agents; Phenothiazines; Cisplatin; Neutral Red; Dimethyl Sulfoxide; Methylene Blue
PubMed: 37353536
DOI: 10.1038/s41598-023-36721-0 -
Journal of the National Medical... Aug 1984This study, based in a psychiatric hospital, reviews the incidence of breast cancer in 93 patients who had received phenothiazines prior to developing breast cancer...
This study, based in a psychiatric hospital, reviews the incidence of breast cancer in 93 patients who had received phenothiazines prior to developing breast cancer compared with a control group of 28 patients who did not receive phenothiazines. The results indicate no significant difference in the incidence of breast cancer between those patients receiving phenothiazines and those that did not. The retrospective study covered a period of 21 years. The overall incidence of breast cancer in 63,000 female patients was found to be 1.85/1,000 as compared with 2/1,000 in the general population.
Topics: Actuarial Analysis; Adult; Aged; Breast Neoplasms; Female; Humans; Mental Disorders; Middle Aged; Phenothiazines; Retrospective Studies
PubMed: 6471116
DOI: No ID Found -
Journal of Advanced Research Mar 2022Cancer is a big challenge of the 21 century, whose defeat requires efficient antitumor drugs.
INTRODUCTION
Cancer is a big challenge of the 21 century, whose defeat requires efficient antitumor drugs.
OBJECTIVES
The paper aims to investigate the synergistic effect of two structural building blocks, phenothiazine and poly(ethylene glycol), towards efficient antitumor drugs.
METHODS
Two PEGylated phenothiazine derivatives were synthetized by attaching poly(ethylene glycol) of 550 Da to the nitrogen atom of phenothiazine by ether or ester linkage. Their antitumor activity has been investigated on five human tumour lines and a mouse tumor line as well, by determination of IC50. The toxicity was determined by measuring the LD50 in BALB/c mice by the sequential method and the antitumor potential was measured by the tumours growth test. The antitumor mechanism was investigated by complexation studies of zinc and magnesium ions characteristic to the farnesyltransferase enzyme, by studies of self-aggregation in the cells proximity and by investigation of the antitumor properties of the acid species resulted by enzymatic cleavage of the PEGylated derivatives.
RESULTS
The two compounds showed antitumor activity, with IC50 against mouse colon carcinoma cell line comparable with that of the traditional antitumor drugs 5-Fluorouracil and doxorubicin. The phenothiazine PEGylation resulted in a significant toxicity diminishing, the LD50 in BALB/c mice increasing from 952.38 up to 1450 mg/kg, in phenothiazine equivalents. Both compounds inflicted a 92% inhibition of the tumour growth for doses much smaller than LD50. The investigation of the possible tumour inhibition mechanism suggested the nanoaggregate formation and the cleavage of ester bonds as key factors for the inhibition of cancer cell proliferation and biocompatibility improvement.
CONCLUSION
Phenothiazine and PEG building blocks have a synergetic effect working for both tumour growth inhibition and biocompatibility improvement. All these findings recommend the PEGylated phenothiazine derivatives as a valuable workbench for a next generation of antitumor drugs.
Topics: Animals; Antineoplastic Agents; Antipsychotic Agents; Esters; Farnesyltranstransferase; Mice; Phenothiazines; Polyethylene Glycols
PubMed: 35499049
DOI: 10.1016/j.jare.2021.07.003 -
Theranostics 2021The tumor suppressor protein p53 remains in a wild type but inactive form in ~50% of all human cancers. Thus, activating it becomes an attractive approach for targeted...
The tumor suppressor protein p53 remains in a wild type but inactive form in ~50% of all human cancers. Thus, activating it becomes an attractive approach for targeted cancer therapies. In this regard, our lab has previously discovered a small molecule, Inauhzin (INZ), as a potent p53 activator with no genotoxicity. To improve its efficacy and bioavailability, here we employed nanoparticle encapsulation, making INZ-C, an analog of INZ, to nanoparticle-encapsulated INZ-C (n-INZ-C). This approach significantly improved p53 activation and inhibition of lung and colorectal cancer cell growth by n-INZ-C and while it displayed a minimal effect on normal human Wi38 and mouse MEF cells. The improved activity was further corroborated with the enhanced cellular uptake observed in cancer cells and minimal cellular uptake observed in normal cells. pharmacokinetic evaluation of these nanoparticles showed that the nanoparticle encapsulation prolongates the half-life of INZ-C from 2.5 h to 5 h in mice. These results demonstrate that we have established a nanoparticle system that could enhance the bioavailability and efficacy of INZ-C as a potential anti-cancer therapeutic.
Topics: Animals; Antineoplastic Agents; Biological Availability; Cell Line, Tumor; Cell Movement; Cell Proliferation; Colorectal Neoplasms; Humans; Indoles; Lung Neoplasms; Mice; Mice, Inbred C57BL; Microscopy, Electron, Transmission; Nanoparticles; Phenothiazines; Spectroscopy, Fourier Transform Infrared; Tumor Suppressor Protein p53; Xenograft Model Antitumor Assays
PubMed: 34093867
DOI: 10.7150/thno.57404 -
Journal of Medicinal Chemistry Feb 2019The phenothiazine system was identified as a favorable cap group for potent and selective histone deacetylase 6 (HDAC6) inhibitors. Here, we report the preparation and...
The phenothiazine system was identified as a favorable cap group for potent and selective histone deacetylase 6 (HDAC6) inhibitors. Here, we report the preparation and systematic variation of phenothiazines and their analogues containing a benzhydroxamic acid moiety as the zinc-binding group. We evaluated their ability to selectively inhibit HDAC6 by a recombinant HDAC enzyme assay, by determining the protein acetylation levels in cells by western blotting (tubulin vs histone acetylation), and by assessing their effects on various cancer cell lines. Structure-activity relationship studies revealed that incorporation of a nitrogen atom into the phenothiazine framework results in increased potency and selectivity for HDAC6 (more than 500-fold selectivity relative to the inhibition of HDAC1, HDAC4, and HDAC8), as rationalized by molecular modeling and docking studies. The binding mode was confirmed by co-crystallization of the potent azaphenothiazine inhibitor with catalytic domain 2 from Danio rerio HDAC6.
Topics: Acetylation; Animals; Catalytic Domain; Cells, Cultured; Crystallography, X-Ray; HL-60 Cells; Histone Deacetylase 6; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; In Vitro Techniques; Microsomes, Liver; Molecular Docking Simulation; Molecular Structure; Phenothiazines; Structure-Activity Relationship; Zebrafish
PubMed: 30645113
DOI: 10.1021/acs.jmedchem.8b01090 -
Microbiology Spectrum Aug 2023Infections by pathogenic Acinetobacter species represent a significant burden on the health care system, despite their relative rarity, due to the difficulty of treating...
Infections by pathogenic Acinetobacter species represent a significant burden on the health care system, despite their relative rarity, due to the difficulty of treating infections through oral antibiotics. Multidrug resistance is commonly observed in clinical Acinetobacter infections and multiple molecular mechanisms have been identified for this resistance, including multidrug efflux pumps, carbapenemase enzymes, and the formation of bacterial biofilm in persistent infections. Phenothiazine compounds have been identified as a potential inhibitor of type IV pilus production in multiple Gram-negative bacterial species. Here, we report the ability of two phenothiazines to inhibit type IV pilus-dependent surface (twitching) motility and biofilm formation in multiple Acinetobacter species. Biofilm formation was inhibited in both static and continuous flow models at micromolar concentrations without significant cytotoxicity, suggesting that type IV pilus biogenesis was the primary molecular target for these compounds. These results suggest that phenothiazines may be useful lead compounds for the development of biofilm dispersal agents against Gram-negative bacterial infections. Acinetobacter infections are a growing burden on health care systems worldwide due to increasing antimicrobial resistance through multiple mechanisms. Biofilm formation is an established mechanism of antimicrobial resistance, and its inhibition has the potential to potentiate the use of existing drugs against pathogenic Acinetobacter. Additionally, as discussed in the manuscript, anti-biofilm activity by phenothiazines has the potential to help to explain their known activity against other bacteria, including Staphylococcus aureus and Mycobacterium tuberculosis.
Topics: Humans; Acinetobacter baumannii; Acinetobacter Infections; Anti-Bacterial Agents; Biofilms; Phenothiazines; Bacteria; Drug Resistance, Multiple, Bacterial
PubMed: 37341603
DOI: 10.1128/spectrum.01023-23