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International Journal of Cancer Jul 2019Polycomb group proteins are important epigenetic regulators for cell proliferation and differentiation, organ development, as well as initiation and progression of...
Polycomb group proteins are important epigenetic regulators for cell proliferation and differentiation, organ development, as well as initiation and progression of lethal diseases, including cancer. Upregulated Polycomb group proteins, including Enhancer of zeste homolog 2 (EZH2), promote proliferation, migration, invasion and metastasis of cancer cells, as well as self-renewal of cancer stem cells. In our study, we report that EZH2 and embryonic ectoderm development (EED) indicate respective direct interaction with androgen receptor (AR). In the context of AR-positive prostate cancer, EZH2 and EED regulate AR expression levels and AR downstream targets. More importantly, we demonstrate that targeting EZH2 with the small-molecule inhibitor astemizole in cancer significantly represses the EZH2 and AR expression as well as the neoplastic capacities. These results collectively suggest that pharmacologically targeting EZH2 might be a promising strategy for advanced prostate cancer.
Topics: Animals; Astemizole; Cell Line, Tumor; Enhancer of Zeste Homolog 2 Protein; Gene Expression Regulation, Neoplastic; Humans; Male; Mice; Polycomb Repressive Complex 2; Prostatic Neoplasms; Receptors, Androgen; Sequence Analysis, RNA; Signal Transduction; Xenograft Model Antitumor Assays
PubMed: 30628724
DOI: 10.1002/ijc.32118 -
ACS Infectious Diseases Feb 2019A drug repositioning approach was leveraged to derivatize astemizole (AST), an antihistamine drug whose antimalarial activity was previously identified in a...
A drug repositioning approach was leveraged to derivatize astemizole (AST), an antihistamine drug whose antimalarial activity was previously identified in a high-throughput screen. The multistage activity potential against the Plasmodium parasite's life cycle of the subsequent analogues was examined by evaluating against the parasite asexual blood, liver, and sexual gametocytic stages. In addition, the previously reported contribution of heme detoxification to the compound's mode of action was interrogated. Ten of the 17 derivatives showed half-maximal inhibitory concentrations (ICs) of <0.1 μM against the chloroquine (CQ)-sensitive Plasmodium falciparum NF54 ( PfNF54) strain while maintaining submicromolar potency against the multidrug-resistant strain, PfK1, with most showing low likelihood of cross-resistance with CQ. Selected analogues ( PfNF54-IC < 0.1 μM) were tested for cytotoxicity on Chinese hamster ovarian (CHO) cells and found to be highly selective (selectivity index > 100). Screening of AST and its analogues against gametocytes revealed their moderate activity (IC: 1-5 μM) against late stage P. falciparum gametocytes, while the evaluation of activity against P. berghei liver stages identified one compound (3) with 3-fold greater activity than the parent AST compound. Mechanistic studies showed a strong correlation between in vitro inhibition of β-hematin formation by the AST derivatives and their antiplasmodium ICs. Analyses of intracellular inhibition of hemozoin formation within the parasite further yielded signatures attributable to a possible perturbation of the heme detoxification machinery.
Topics: Animals; Antimalarials; Astemizole; CHO Cells; Chloroquine; Cricetulus; Drug Repositioning; Drug Resistance, Multiple; Hemeproteins; Inhibitory Concentration 50; Life Cycle Stages; Plasmodium falciparum
PubMed: 30525439
DOI: 10.1021/acsinfecdis.8b00272 -
Molecular Pharmaceutics Dec 2018The organic anion transporting polypeptide (OATP) 2B1 is ubiquitously expressed and known to facilitate cellular entry. It is widely accepted that transport proteins...
The organic anion transporting polypeptide (OATP) 2B1 is ubiquitously expressed and known to facilitate cellular entry. It is widely accepted that transport proteins play a pivotal role in pharmacokinetics. Consequently, testing for interaction with drug transporters became an important part in the assessment of new molecular entities in order to predict and prevent drug-drug interactions. Recently, competitive counterflow (CCF), an indirect method allowing the identification of substrates, was successfully applied to the organic cation transporter 2. It was the aim of this study to test whether CCF can be used to identify substrates of OATP2B1. A protocol for CCF experiments using estrone 3-sulfate (ES) as the driven compound in expression-verified MDCKII-OATP2B1 cells was established. The protocol was tested using a substance library, which was prior screened for inhibition of OATP2B1-mediated transport accounting for both ES-binding sites. In CCF experiments, all previously reported OATP2B1 substrates significantly reduced the amount of ES in equilibrium, classifying them as substrates. In addition, we identified and verified novel substrates of OATP2B1, namely, astemizole and domperidone. Results of the CCF were complemented with cytotoxicity assays or cell-based reporter gene assays to validate the finding of etoposide and teniposide or hyperforin being substrates of OATP2B1, respectively. Our study indicates that the method of CCF can be used to identify substrates of OATP2B1, irrespective, whether interacting with binding site A or A and B, but is limited by solubility issues or the amount of transporter that is expressed in the used cellular system.
Topics: Animals; Chemistry, Pharmaceutical; Dogs; Drug Interactions; Estrone; HeLa Cells; Hep G2 Cells; Humans; Madin Darby Canine Kidney Cells; Organic Anion Transporters; Recombinant Proteins; Small Molecule Libraries; Substrate Specificity
PubMed: 30380886
DOI: 10.1021/acs.molpharmaceut.8b00631 -
International Immunopharmacology Dec 2018In this study, the immunomodulatory effects of astemizole (AST) against lipopolysaccharide (LPS) mediated T cell proliferation and induction of inflammation in RAW...
Immunosuppressive potential of astemizole against LPS activated T cell proliferation and cytokine secretion in RAW macrophages, zebrafish larvae and mouse splenocytes by modulating MAPK signaling pathway.
In this study, the immunomodulatory effects of astemizole (AST) against lipopolysaccharide (LPS) mediated T cell proliferation and induction of inflammation in RAW macrophages (in vitro), and zebrafish larvae (in vivo) were determined. AST significantly suppressed the phagocytic activity of macrophages (3.303 ± 0.115) and inhibited lysosomal enzyme secretion (13.27 ± 2.52) induced by LPS (100 ng/ml). Moreover, AST subdued the morphological deformities such as yolk sac edema (YSE) and spinal curvature curving (SC) by inhibiting ROS generation in zebrafish larvae 24 h after microinjection of LPS (0.5 mg/ml). AST was also shown to inhibit the production of the major cytokines TNF-α (150.8 ± 0.6), IL-1β (276.5 ± 1.6), and PGE (194.6 ± 0.6) pg/ml in RAW macrophages. It also subdued the ROS induced iNOS and COX-2 generated in response to LPS mediated immune dysfunctions in zebrafish larvae. These results suggested the immunosuppression effect of AST. Furthermore, induction of immune-suppression due to AST resulted in significant down-regulation of innate immunity directed by MAPK (p38, ERK and JNK), which was found to be associated with decreased production of acute inflammatory mediators both in vitro and in vivo. To confirm its activity, splenocytes were prepared using BALB/c mice and a mitogen activated splenocyte proliferation assay was also performed. Our findings suggest that AST has the ability to inhibit T cell proliferation and cytokine secretion both in vitro and in vivo by interfering with MAPK signaling pathway. Taken together, our results showed the potential of AST as a countermeasure to immune dysfunction and suggest its use as immunosuppressant compound in inflammatory disease.
Topics: Animals; Astemizole; Cell Proliferation; Cytokines; Extracellular Signal-Regulated MAP Kinases; Fish Proteins; Immunosuppressive Agents; Larva; Lipopolysaccharides; Lymphocyte Activation; Macrophages; Mice; RAW 264.7 Cells; Signal Transduction; Spleen; T-Lymphocytes; Zebrafish
PubMed: 30359933
DOI: 10.1016/j.intimp.2018.10.014 -
Scientific Reports Sep 2018We examined a simultaneous combined spatiotemporal field potential duration (FPD) and cell-to-cell conduction time (CT) in lined-up shaped human embryonic stem...
We examined a simultaneous combined spatiotemporal field potential duration (FPD) and cell-to-cell conduction time (CT) in lined-up shaped human embryonic stem cell-derived cardiomyocytes (hESC-CMs) using an on-chip multielectrode array (MEA) system to evaluate two origins of lethal arrhythmia, repolarization and depolarization. The repolarization index, FPD, was prolonged by E-4031 and astemizole, and shortened by verapamil, flecainide and terfenadine at 10 times higher than therapeutic plasma concentrations of each drug, but it did not change after lidocaine treatment up to 100 μM. CT was increased by astemizol, flecainide, terfenadine, and lidocaine at equivalent concentrations of Nav1.5 IC, suggesting that CT may be an index of cardiac depolarization because the increase in CT (i.e., decrease in cell-to-cell conduction speed) was relevant to Nav1.5 inhibition. Fluctuations (short-term variability; STV) of FPD and CT, STV and STV also discriminated between torsadogenic and non-torsadogenic compounds with significant increases in their fluctuation values, enabling precise prediction of arrhythmogenic risk as potential new indices.
Topics: Arrhythmias, Cardiac; Cell Line; Drug Development; Drug Evaluation, Preclinical; Equipment Design; Human Embryonic Stem Cells; Humans; Lab-On-A-Chip Devices; Myocytes, Cardiac
PubMed: 30266924
DOI: 10.1038/s41598-018-32921-1 -
Biomedicine & Pharmacotherapy =... Nov 2018Hepatocellular carcinoma (HCC) accounts for the fifth most common cancer worldwide. Vitamin D and antihistamines have been shown to play an anti-tumor role in various...
Hepatocellular carcinoma (HCC) accounts for the fifth most common cancer worldwide. Vitamin D and antihistamines have been shown to play an anti-tumor role in various tumors. In the present study, we ought to investigate the synergistic effect of astemizole and Vitamin D in HCC cells. We showed that astemizole enhanced the anti-tumor effect of Vitamin D in HCC both in vitro and in vivo. Astemizole enhanced Vitamin D-induced decrease of cell viability and proliferation, increase of apoptosis, decrease of cell migration and invasion in HCC cells in vitro and decrease of tumor number, mass and incidence in HCC in vivo. Astemizole increased VDR expression both in HCC cells in vitro and in tumor tissues in vivo. Downregulation of VDR significantly inhibited the synergistic effect of Vitamin D and astemizole on HCC cell viability, proliferation, apoptosis, migration and invasion. Bioinformatics analysis identified that miR-125a-5p had a putative binding site in the 3'-UTR of VDR. miR-125a-5p mimics inhibited astemizole-induced increase of VDR and enhancement of the anti-tumor effect of Vitamin D in HCC. Reporter gene assay has confirmed that VDR was regulated by miR-125a-5p. miR-125a-5p inhibitors increased VDR expression and decreased cell viability and proliferation in HCC cells. Moreover, VDR and miR-125a-5p expression in tumor tissues in HCC patients were negatively correlated. We identified that inhibition of miR-125a-5p and subsequent upregulation of VDR was involved in astemizole-induced enhancement of the anti-tumor effect of Vitamin D in HCC. These results highlight the importance of combined treatment of astemizole and Vitamin D and provide novel insights into the role of miR-125a-5p-VDR signaling in HCC.
Topics: 3' Untranslated Regions; Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Astemizole; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Movement; Cell Proliferation; Down-Regulation; Gene Expression Regulation, Neoplastic; Hep G2 Cells; Humans; Liver Neoplasms; Mice; Mice, Inbred C57BL; MicroRNAs; Receptors, Calcitriol; Up-Regulation; Vitamin D
PubMed: 30257386
DOI: 10.1016/j.biopha.2018.08.153 -
Journal of Clinical Pharmacy and... Feb 2019In order to expedite the availability of drugs to treat cancers in a cost-effective manner, repurposing of old drugs for oncological indications is gathering momentum.... (Review)
Review
WHAT IS KNOWN AND OBJECTIVE
In order to expedite the availability of drugs to treat cancers in a cost-effective manner, repurposing of old drugs for oncological indications is gathering momentum. Revolutionary advances in pharmacology and genomics have demonstrated many old drugs to have activity at novel antioncogenic pharmacological targets. We decided to investigate whether prospective studies support the promises of nonclinical and retrospective clinical studies on repurposing three old drugs, namely metformin, valproate and astemizole.
METHODS
We conducted an extensive literature search through PubMed to gather representative nonclinical and retrospective clinical studies that investigated the potential repurposing of these three drugs for oncological indications. We then searched for prospective studies aimed at confirming the promises of retrospective data.
RESULTS AND DISCUSSION
While evidence from nonclinical and retrospective clinical studies with these drugs appears highly promising, large scale prospective studies are either lacking or have failed to substantiate this promise. We provide a brief discussion of some of the challenges in repurposing. Principal challenges and obstacles relate to heterogeneity of cancers studied without considering their molecular signatures, trials with small sample size and short duration, failure consider issues of ethnicity of study population and effective antioncogenic doses of the drug studied.
WHAT IS NEW AND CONCLUSION
Well-designed prospective studies demonstrating efficacy are required for repurposing old drugs for oncology indications, just as they are for new chemical entities for any indication. Early and ongoing interactions with regulatory authorities are invaluable. We outline a tentative framework for a structured approach to repurposing old drugs for novel indications in oncology.
Topics: Antineoplastic Agents; Astemizole; Cost-Benefit Analysis; Drug Repositioning; Genomics; Humans; Metformin; Neoplasms; Research Design; Valproic Acid
PubMed: 30218625
DOI: 10.1111/jcpt.12759 -
Drug Metabolism Letters 2018We report here an evaluation of a novel experimental system- cofactorsupplemented permeabilized cryopreserved human enterocytes (MetMax™ cryopreserved human... (Comparative Study)
Comparative Study
A Novel In vitro Experimental System for the Evaluation of Enteric Drug Metabolism: Cofactor-Supplemented Permeabilized Cryopreserved Human Enterocytes (MetMax™ Cryopreserved Human Enterocytes).
BACKGROUND
We report here an evaluation of a novel experimental system- cofactorsupplemented permeabilized cryopreserved human enterocytes (MetMax™ cryopreserved human enterocytes (MMHE), patent pending) for applications in the evaluation of enteric drug metabolism. A major advantage of MMHE over Conventional Cryopreserved Human Enterocytes (CCHE) is the simplification of the use procedures including storage at -80°C instead of in liquid nitrogen, and use of the cells immediately after thawing without a need for centrifugation and microscopic evaluation of cell density and viability and cell density adjustment.
METHODS
In this study, we compared MMHE and CCHE in key phase 1 oxidation and phase 2 conjugation Drug Metabolism Enzyme (DME) activities that we recently reported for cryopreserved human enterocytes: CYP2C9 (diclofenac 4'- hydroxylation), CYP2C19 (s-mephenytoin hydroxylation), CYP3A4 (midazolam 1'-hydroxylation), CYP2J2 (astemizole O-demethylation), uridine 5'-diphosphoglucuronosyltransferase (UGT; 7-hydroxycoumarin glucuronidation), sulfotransferase (SULT; 7- hydroxycoumarin sulfation), N-acetyl transferase-1 (NAT-1; p-benzoic acid N-acetylation), and carboxyesterase- 2 (CES-2; hydrolysis of irinotecan to SN38). Both CCHE and MMHE were active in all the DME pathways evaluated, with specific activities of MMHE ranged from 142% (CYP2C9) to 1713% (UGT) of that for CCHE. β-hydroxylation and testosterone 6.
RESULT AND CONCLUSION
Our results suggest that the MMHE system represents a convenient and robust in vitro experimental system for the evaluation of enteric drug metabolism.
Topics: Adult; Biotransformation; Carboxylesterase; Cell Membrane Permeability; Cryopreservation; Cytochrome P-450 Enzyme System; Enterocytes; Female; Glucuronosyltransferase; Humans; In Vitro Techniques; Isoenzymes; Male; Middle Aged; Pharmaceutical Preparations; Sulfotransferases
PubMed: 30124163
DOI: 10.2174/1872312812666180820142141 -
International Journal of Biological... 2018Cholesterol plays a key role in membrane protein function and signaling in endothelial cells. Thus, disturbing cholesterol trafficking is an effective approach for...
Cholesterol plays a key role in membrane protein function and signaling in endothelial cells. Thus, disturbing cholesterol trafficking is an effective approach for inhibiting angiogenesis. We recently identified astemizole (AST), an antihistamine drug, as a cholesterol trafficking inhibitor from a phenotypic screen. In this study, we found that AST induced cholesterol accumulation in the lysosome by binding to the sterol-sensing domain of Niemann-Pick disease, type C1 (NPC1), a lysosomal surface protein responsible for cholesterol transport. Inhibition of cholesterol trafficking by AST led to the depletion of membrane cholesterol, causing SREBP1 nuclear localization. The depletion of membrane cholesterol resulted in dissociation of mammalian target of rapamycin (mTOR) from the lysosomal surface and inactivation of mTOR signaling. These effects were effectively rescued by addition of exogenous cholesterol. AST inhibited endothelial cell proliferation, migration and tube formation in a cholesterol-dependent manner. Furthermore, AST inhibited zebrafish angiogenesis in a cholesterol-dependent manner. Together, our data suggest that AST is a new class of NPC1 antagonist that inhibits cholesterol trafficking in endothelial cells and angiogenesis.
Topics: A549 Cells; Astemizole; Biological Transport; Blotting, Western; Cell Movement; Cell Proliferation; Cholesterol; Fluorescent Antibody Technique; Human Umbilical Vein Endothelial Cells; Humans; Neovascularization, Pathologic; Niemann-Pick C1 Protein; Signal Transduction; TOR Serine-Threonine Kinases
PubMed: 30123067
DOI: 10.7150/ijbs.26011 -
The Analyst Aug 2018We previously reported the kinetics analysis of cardiomyocyte beating using scanning electrochemical microscopy (SECM). In this study, a stage-top incubator and a...
We previously reported the kinetics analysis of cardiomyocyte beating using scanning electrochemical microscopy (SECM). In this study, a stage-top incubator and a capillary micropipette (MP) for delivering drugs were assembled with an SECM instrument, and the responses of rat cardiomyocytes were analyzed under a culture environment after drug stimulation. When adenosine triphosphate (ATP) was delivered to synchronously beating cardiomyocytes, the beating acceleration effect of ATP was counteracted by the synchronously beating network in the culture dish. In contrast, cardiomyocytes cultured on a pattern of islands in a culture dish showed fluctuations in the duration of beating upon the addition of ATP. We also examined the effect of the cardiotoxic agent astemizole on cardiomyocytes and successfully detected motion fluctuations. Therefore, drug stimulation via MPs and beating measurement by SECM are effective routes for the evaluation of drug candidates through the analysis of time-course beating motion fluctuations of the cardiomyocytes.
Topics: Adenosine Triphosphate; Animals; Cell Culture Techniques; Cells, Cultured; Microscopy, Electrochemical, Scanning; Myocytes, Cardiac; Pharmaceutical Preparations; Rats; Time Factors
PubMed: 30083681
DOI: 10.1039/c8an01033a