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1.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(1): 1-6, 2020 Feb 28.
Artigo em Chinês | MEDLINE | ID: mdl-32131933

RESUMO

Objective To investigate the effect of α-asarone on the function and expression of P-glycoprotein(P-gp)in rat brain microvascular endothelial cells(rBMECs). Methods rBMECs were exposed to L-glutamate(100 µmol/L) for 30 mins to induce the overexpression of P-gp/multidrug resistance gene 1a(Mdr1a)on the cell membranes,which mimicked the overexpression of P-gp/Mdr1a in blood brain barrier(BBB) when drug-resistant epilepsy attacked.MTT assay was used to detect the safe range of α-asarone concentration.The model cells were intervened with different concentrations of α-asarone at 12.5,25.0,and 50.0 µg/µl for 24 hours.After the treatment of α-asarone,the expression and the function of P-gp/Mdr1 were measured by Western blotting,real-time PCR,and intracellular rhodamine 123 accumulation assays. Results The rBMECs,stimulated by glutamine,showed a high expression of P-gp(F=1.924,P=0.020)/Mdr1a(F=1.788,P=0.019) compared to the normal rBMECs.The treatment with 25.0(F=1.924,P=0.025;F=1.788,P=0.017) and 50.0 µg/µl(F=1.924,P=0.035;F=1.788,P=0.026) α-asarone significantly depressed the expression of P-gp/Mdr1a.The treatment with 25.0 and 50.0 µg/µl α-asarone significantly increased intracellular accumulation of Rhodamine 123 by 40% and 60% respectively. Conclusions α-asarone down-regulates the high expressions of P-gp and Mdr1a mRNA in rBMECs induced by L-glutamate.Moreover and increases intracellular accumulation of rhodamine-123.Thus,α-asarone may reverse drug resistance in P-gp-mediated drug-resistant epilepsy.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Anisóis/farmacologia , Encéfalo/citologia , Células Endoteliais/efeitos dos fármacos , Animais , Células Cultivadas , Epilepsia Resistente a Medicamentos , Células Endoteliais/metabolismo , Ácido Glutâmico , Ratos
2.
Medicine (Baltimore) ; 99(8): e19189, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32080102

RESUMO

Studies on the relationship between ABCB1 3435C>T polymorphism (rs1045642) and colorectal cancer (CRC)susceptibility have yielded inconclusive results. To clarify this issue, we undertook a meta-analysis to investigate the relationship between rs1045642 and CRC risk.Three electronic scientific publication databases (Cochrane Library, Pubmed, Embase) were screened using specific search terms. Relevant literature was identified using literature traceability methods. Selected publications were evaluated according to the inclusion and exclusion criteria. Effect size information (odds ratio and the corresponding 95% confidence interval [CI]) was obtained following quality assessment and data extraction from the included publications, and a meta-analysis conducted. Statistical analysis was performed with the Stata sofz (Version 13.0) software.Overall, 17 case-control studies involving 7129 CRC patients and 7710 healthy control subjects satisfied the criteria for inclusion in the meta-analysis. There was no significant association between ABCB1 3435C>T polymorphism and CRC risk in any of the genetic models. In the CC versus CT model (I = 20.9%, Pheterogeneity = .276), CC versus CT + TT model (I = 45.6%, Pheterogeneity = .102) and CT versus CC + TT model (I = 17.8%, Pheterogeneity = .298) analyses, between-study heterogeneities were detected as significant in Asian populations. In the CT versus TT model (I = 24%, Pheterogeneity = .254) and CC + CT versus TT model (I = 0, Pheterogeneity = .55), between-study heterogeneities were found to be significant in groups of different populations.The meta-analysis described here suggests that the ABCB1 3435C>T polymorphism is not related to CRC susceptibility.


Assuntos
Neoplasias Colorretais/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco
3.
Toxicol Lett ; 324: 104-110, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32092453

RESUMO

Dietary and microbial indoles can act as ligands and activators of pregnane X receptor (PXR), with implications in human intestinal health. In the current study, we examined the effects of simple mono-methylated indoles (MMIs) on the activity and function of PXR, using a series of human hepatic and intestinal cell models. Indoles 1-MMI and 2-MMI strongly induced CYP3A4 and MDR1 mRNAs in human intestinal adenocarcinoma cells LS180, but not in primary human hepatocytes. The levels of CYP3A4 mRNA were increased by 1-MMI and 2-MMI in wild type, but not in PXR-knock-out human hepatic progenitor HepaRG cells, implying the involvement of PXR in CYP3A4 induction by MMIs. Utilizing reporter gene assay, we observed dose-dependent activation of PXR by all MMIs, and their efficacies and potencies were comparable. Tested MMIs also displayed moderate antagonist effects on PXR, revealing about partial agonist effects of these compounds. As demonstrated using the Chromatin immunoprecipitation assay (ChIP),1-MMI increased PXR occupancy of the CYP3A4 promoter. Time-Resolved Fluorescence Resonance Energy Transfer revealed that MMIs are weak ligands of human PXR. Collectively, we show that MMIs are ligands and partial agonists of human PXR, which induce PXR-regulated genes in human intestinal cells.


Assuntos
Hepatócitos/efeitos dos fármacos , Indóis/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Receptor de Pregnano X/efeitos dos fármacos , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Linhagem Celular Tumoral , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/fisiologia , Hepatócitos/metabolismo , Humanos , Indóis/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Receptor de Pregnano X/genética , Receptor de Pregnano X/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais/efeitos dos fármacos
4.
J Cancer Res Clin Oncol ; 146(4): 843-858, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32056006

RESUMO

PURPOSE: Increased ATP-binding-cassette (ABC) transporter activity is a major cause of chemotherapy resistance in cancer. The ABC transporter family member ABCB1 is often overexpressed in colorectal cancer (CRC). Phosphatidylinositol-4,5-bisphosphat (PI(4,5)P2)-dependent pathways are involved in the regulation of ABCB1 function. The protein Myristoylated Alanine-Rich C-Kinase Substrate (MARCKS) is a pivotal regulator of PI(4,5)P2 and inactivated in many CRC cancers via genetic deletion or hyperphosphorylation. Therefore, MARCKS may critically impact ABCB1. METHODS: CRC samples as well as CRC cell lines were tested for a connection between MARCKS and ABCB1 via immunofluorescence and Western-blot analysis. ABCB1 function was studied via calcein influx assay under treatment with known ABCB1 inhibitors (verapamil, tariquidar) as well as the kinase inhibitor bosutinib. ABCB1 internalization and MARCKS translocation was analyzed via confocal microscopy exploiting the endocytosis inhibitors chlorpromazine and dynasore. Abundance of PI(4,5)P2 was monitored by intramolecular fluorescence resonance energy transfer (FRET). Reproductive cell survival was studied via colorimetric WST-1 and clonogenic assays in combination with exposure to the chemotherapeutics doxorubicin and 5-fuorouracil (5-FU). RESULTS: We found increased ABCB1 expression in MARCKS negative CRC patient tumor samples and established CRC cell lines. Mechanistically, the reconstitution of MARCKS function via recombinant expression or the pharmacological inhibition of MARCKS phosphorylation led to a substantial decrease in ABCB1 activity. In CRC cells, bosutinib treatment resulted in a MARCKS translocation from the cytosol to the plasma membrane, while simultaneously, ABCB1 was relocated to intracellular compartments. Inhibition of MARCKS phosphorylation via bosutinib rendered cells more sensitive to the chemotherapeutics doxorubicin and 5-FU. CONCLUSIONS: Cells devoid of MARCKS function showed incomplete ABCB1 internalization, leading to higher ABCB1 activity enhancing chemoresistance. Vice versa our data suggest the prevention of MARCKS inhibition by reversing hyperphosphorylation or genomic restoration after deletion as two promising approaches to overcome tumor cell resistance towards chemotherapeutic ABCB1 substrates.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Substrato Quinase C Rico em Alanina Miristoilada/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Compostos de Anilina , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Fluoresceínas/metabolismo , Transferência Ressonante de Energia de Fluorescência , Células HT29 , Humanos , Microscopia Confocal , Substrato Quinase C Rico em Alanina Miristoilada/deficiência , Nitrilos , Fosforilação , Quinolinas
5.
PLoS One ; 15(2): e0228848, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32050000

RESUMO

We investigated the relation of 99mTc-MIBI uptake to mitochondrial membrane potential (MMP) in cancer cell lines and patient-derived tumor cells (PDCs). In T47D and HT29 cells with low MDR1 expression, FCCP dose-dependently reduced MMP and 99mTc-MIBI accumulation in similar patterns with nearly perfect linear relationships. T47D and HT29 cells with high MDR1 expression had low 99mTc-MIBI accumulation that was minimally affected by FCCP dose. In these cells, verapamil markedly increased 99mTc-MIBI accumulation to magnitudes that were excessive compared to MMP increase. Decreased plasma membrane potential by verapamil and its recovery by FCCP suggested that enhanced 99mTc-MIBI transport through modified plasma membranes contributed to the excess accumulation. Evaluation of three different colon cancer PDCs with low to modest MDR1 expression verified that FCCP significantly suppressed MMP and similarly reduced 99mTc-MIBI accumulation. Verapamil partially recovered both MMP and 99mTc-MIBI accumulation that was lowered by FCCP. Importantly, a high linear correlation was found (r = 0.865) between 99mTc-MIBI accumulation and MMP in these cells. These findings indicate that low baseline 99mTc-MIBI uptake that is markedly increased by verapamil represents cancer cells with high levels of MDR1 expression. However, in cancer cells with low or modest levels of MDR1 expression that do not markedly increase 99mTc-MIBI uptake by verapamil, the magnitude of uptake is largely dependent on cellular MMP.


Assuntos
Transporte Biológico/fisiologia , Potencial da Membrana Mitocondrial/fisiologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Tecnécio Tc 99m Sestamibi/metabolismo , Verapamil/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membrana Celular/metabolismo , Resistência a Múltiplos Medicamentos/fisiologia , Células HT29 , Humanos , Compostos Radiofarmacêuticos/metabolismo , Células Tumorais Cultivadas
6.
Int J Cancer ; 146(6): 1631-1642, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31304590

RESUMO

Galunisertib (LY2157299), a promising small-molecule inhibitor of the transforming growth factor-beta (TGF-ß) receptor, is currently in mono- and combination therapy trials for various cancers including glioblastoma, hepatocellular carcinoma and breast cancer. Using genetically modified mouse models, we investigated the roles of the multidrug efflux transporters ABCB1 and ABCG2, the OATP1A/1B uptake transporters and the drug-metabolizing CYP3A complex in galunisertib pharmacokinetics. In vitro, galunisertib was vigorously transported by human ABCB1, and moderately by mouse Abcg2. Orally administered galunisertib (20 mg/kg) was very rapidly absorbed. Galunisertib brain-to-plasma ratios were increased by ~24-fold in Abcb1a/1b-/- and Abcb1a/1b;Abcg2-/- mice compared to wild-type mice, but not in single Abcg2-/- mice, whereas galunisertib oral availability was not markedly affected. However, recovery of galunisertib in the small intestinal lumen was strongly reduced in Abcb1a/1b-/- and Abcb1a/1b;Abcg2-/- mice. Oral coadministration of the ABCB1/ABCG2 inhibitor elacridar boosted galunisertib brain accumulation in wild-type mice to equal the levels seen in Abcb1a/1b;Abcg2-/- mice. Oatp1a/1b deficiency did not alter oral galunisertib pharmacokinetics or liver distribution. Cyp3a-/- mice showed a 1.9-fold higher plasma AUC0-1 hr than wild-type mice, but this difference disappeared over 8 hr. Also, transgenic human CYP3A4 overexpression did not significantly alter oral galunisertib pharmacokinetics. Abcb1 thus markedly restricts galunisertib brain penetration and affects its intestinal disposition, possibly through biliary excretion. Elacridar coadministration could fully inhibit both processes, without causing acute toxicity. Moreover, mouse Cyp3a, but not human CYP3A4, may eliminate galunisertib at high plasma concentrations. These insights may help to guide the further clinical development and application of galunisertib.


Assuntos
Encéfalo/metabolismo , Pirazóis/farmacocinética , Quinolinas/farmacocinética , Fator de Crescimento Transformador beta/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Acridinas/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Citocromo P-450 CYP3A/metabolismo , Cães , Feminino , Interações Ervas-Drogas , Humanos , Células Madin Darby de Rim Canino , Camundongos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Pirazóis/sangue , Pirazóis/farmacologia , Quinolinas/sangue , Quinolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Tetra-Hidroisoquinolinas/farmacologia , Distribuição Tecidual
7.
Cancer Sci ; 111(1): 84-97, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31774615

RESUMO

Although accumulating evidence has indicated the intimate association between epithelial-mesenchymal transition (EMT) and acquired resistance to chemotherapy for colorectal cancer (CRC), the underlying mechanisms remain elusive. Herein, we reported that Snail, a crucial EMT controller, was upregulated in CRC tissues. Colorectal cancer cells overexpressing Snail were found to be more resistant to 5-fluorouracil (5-Fu). Mechanistic studies reveal that Snail could increase the expression of ATP-binding cassette subfamily B member 1 (ABCB1) rather than the other 23 chemoresistance-related genes. Additionally, knockdown of ABCB1 significantly attenuated Snail-induced 5-Fu resistance in CRC cells. Oxaliplatin increased Snail and ABCB1 expression in CRC cells. Snail and ABCB1 were upregulated in 5-Fu-resistant HCT-8 (HCT-8/5-Fu) cells and inhibition of Snail decreased ABCB1 in HCT-8/5-Fu cells. These results confirm the vital role played by ABCB1 in Snail-induced chemoresistance. Further investigation into the relevant molecular mechanism revealed Snail-mediated ABCB1 upregulation was independent of ß-catenin, STAT3, PXR, CAR and Foxo3a, which are commonly involved in modulating ABCB1 transcription. Instead, Snail upregulated ABCB1 transcription by directly binding to its promoter. Clinical analysis confirms that increased Snail expression correlated significantly with tumor size (P = .018), lymph node metastasis (P = .033), distant metastasis (P = .025), clinical stage grade (P = .024), and poor prognosis (P = .045) of CRC patients. Moreover, coexpression of Snail and ABCB1 was observed in CRC patients. Our study revealed that direct regulation of ABCB1 by Snail was critical for conferring chemoresistance in CRC cells. These findings unraveled the mechanisms underlying the association between EMT and chemoresistance, and provided potential targets for CRC clinical treatment.


Assuntos
Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Fatores de Transcrição da Família Snail/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Linhagem Celular , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Transdução de Sinais/genética , Regulação para Cima/genética
8.
Nat Struct Mol Biol ; 27(1): 62-70, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31873305

RESUMO

ABCB4 is an ATP-binding cassette transporter that extrudes phosphatidylcholine into the bile canaliculi of the liver. Its dysfunction or inhibition by drugs can cause severe, chronic liver disease or drug-induced liver injury. We determined the cryo-EM structure of nanodisc-reconstituted human ABCB4 trapped in an ATP-bound state at a resolution of 3.2 Å. The nucleotide binding domains form a closed conformation containing two bound ATP molecules, but only one of the ATPase sites contains bound Mg2+. The transmembrane domains adopt a collapsed conformation at the level of the lipid bilayer, but we observed a large, hydrophilic and fully occluded cavity at the level of the cytoplasmic membrane boundary, with no ligand bound. This indicates a state following substrate release but prior to ATP hydrolysis. Our results rationalize disease-causing mutations in human ABCB4 and suggest an 'alternating access' mechanism of lipid extrusion, distinct from the 'credit card swipe' model of other lipid transporters.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/ultraestrutura , Trifosfato de Adenosina/metabolismo , Sítios de Ligação , Microscopia Crioeletrônica , Humanos , Hidrólise , Bicamadas Lipídicas/química , Modelos Moleculares , Conformação Proteica , Especificidade por Substrato
9.
Int J Cancer ; 146(1): 192-207, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31107974

RESUMO

Malignant pleural mesothelioma (MPM) is a tumor with high chemoresistance and poor prognosis. MPM-initiating cells (ICs) are known to be drug resistant, but it is unknown if and how stemness-related pathways determine chemoresistance. Moreover, there are no predictive markers of IC-associated chemoresistance. Aim of this work is to clarify if and by which mechanisms the chemoresistant phenotype of MPM IC was due to specific stemness-related pathways. We generated MPM IC from primary MPM samples and compared the gene expression and chemo-sensitivity profile of IC and differentiated/adherent cells (AC) of the same patient. Compared to AC, IC had upregulated the drug efflux transporter ABCB5 that determined resistance to cisplatin and pemetrexed. ABCB5-knocked-out (KO) IC clones were resensitized to the drugs in vitro and in patient-derived xenografts. ABCB5 was transcriptionally activated by the Wnt/GSK3ß/ß-catenin/c-myc axis that also increased IL-8 and IL-1ß production. IL-8 and IL-1ß-KO IC clones reduced the c-myc-driven transcription of ABCB5 and reacquired chemosensitivity. ABCB5-KO clones had lower IL-8 and IL-1ß secretion, and c-myc transcriptional activity, suggesting that either Wnt/GSK3ß/ß-catenin and IL-8/IL-1ß signaling drive c-myc-mediated transcription of ABCB5. ABCB5 correlated with lower time-to-progression and overall survival in MPM patients treated with cisplatin and pemetrexed. Our work identified multiple autocrine loops linking stemness pathways and resistance to cisplatin and pemetrexed in MPM IC. ABCB5 may represent a new target to chemosensitize MPM IC and a potential biomarker to predict the response to the first-line chemotherapy in MPM patients.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Resistencia a Medicamentos Antineoplásicos/genética , Interleucina-1beta/metabolismo , Interleucina-8/metabolismo , Mesotelioma/tratamento farmacológico , Neoplasias Pleurais/tratamento farmacológico , Via de Sinalização Wnt , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Feminino , Humanos , Mesotelioma/metabolismo , Mesotelioma/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Neoplasias Pleurais/metabolismo , Neoplasias Pleurais/patologia
10.
Eur J Pharm Sci ; 141: 105095, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31626965

RESUMO

PURPOSE: The aim of the present study was to develop a population pharmacokinetic model of midazolam, and to evaluate the influence of maturation process and other variability factors in critically ill children with severe acute bronchiolitis, who received a long-term intravenous infusion of midazolam. METHODS: In the study were included 49 critically ill children of both genders (from 0 to 130 weeks of age) with severe acute bronchiolitis hospitalised in intensive care units. Nonlinear mixed effects modelling approach was applied for data analyses and simulations. RESULTS: The final model is a two-compartment model that includes the effects of body weight using allometric scaling with fixed exponents and maturation of clearance. For a typical subject, scaled to the adult body weight of 70 kg, population pharmacokinetic values were estimated at 8.52 L/h for clearance (when maturation function was 1), 25.5 L/h for intercompartmental clearance, and 5.71 L and 39.8 L for the volume of the central and peripheral compartment, respectively. Based on the final model, maturation reaches 50% of the adult clearance in 45.9 weeks of postmenstrual age. The influence of gender, ABCB1 genotype and biochemical parameters on midazolam clearance was not detected. Results of simulations indicate the need for reduced dosing in certain groups of patients in order to maintain plasma concentrations of midazolam within recommended values. CONCLUSIONS: The developed population pharmacokinetic model can contribute to the dosing optimisation of midazolam, especially in critically ill children as it includes the influence of size and maturation of clearance, which are important parameters for achieving the desired plasma concentrations of midazolam.


Assuntos
Hipnóticos e Sedativos/farmacocinética , Midazolam/farmacocinética , Modelos Biológicos , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Bronquiolite/genética , Bronquiolite/metabolismo , Bronquiolite/terapia , Estado Terminal , Feminino , Humanos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/sangue , Lactente , Recém-Nascido , Infusões Intravenosas , Masculino , Midazolam/administração & dosagem , Midazolam/sangue , Polimorfismo de Nucleotídeo Único , Respiração Artificial
11.
Anticancer Res ; 39(12): 6457-6462, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810909

RESUMO

BACKGROUND/AIM: Nicotinamide phosphoribosyltransferase (NAMPT), a key enzyme in the NAD+ biosynthetic pathway, is a drug target of potent anticancer candidates, including FK866 and other reported NAMPT inhibitors. However, it is known that NAMPT point-mutations render resistance to specific NAMPT inhibitors in several cancer cells. We investigated the resistance mechanisms of NAMPT inhibitor FK866 in human colorectal cancer (CRC) cells. MATERIALS AND METHODS: We used CRC human cell line HCT116 to determine the expression profiles of FK866-sensitive parental HCT116 cells and FK866-resistant HCT116 (HCT116RFK866) cells by DNA microarray analysis. The levels of multidrug resistance protein 1 (MDR1) were assessed via western blot. In addition, we analyzed the sensitivity of FK866 in parental HCT116 cells and HCT116RFK866 cells by co-treatment with MDR1 inhibitor verapamil. RESULTS: Our results revealed an association between ATP-binding cassette (ABC) transporter gene ABCB1 and resistance to NAMPT inhibitor FK866 in both HCT116RFK866 cells and parental HCT116 cells. The expression of ABCB1, which encodes MDR1, was lower in HCT116RFK866 cells than in parental HCT116 cells. Furthermore, the protein level of MDR1/ATP-binding cassette sub-family B member 1 (ABCB1) was 0.5-fold lower in HCT116RFK866 cells than in parental HCT116 cells. Additionally, HCT116RFK866 cells showed improved sensitivity to FK866 when co-treated with verapamil, an ABCB1 inhibitor. Interestingly, the efficacy of FK866 in parental HCT116 cells was the same for the treatment with FK866 alone or in combination with verapamil. CONCLUSION: The change in expression of ABCB1 plays a key role in CRC drug resistance to NAMPT inhibitor FK866. This suggests that the MDR1/ABCB1 mechanism may regulate the resistance of anticancer NAMPT inhibitor FK866.


Assuntos
Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Acrilamidas/farmacologia , Neoplasias Colorretais/metabolismo , Citocinas/antagonistas & inibidores , Regulação para Baixo , Sinergismo Farmacológico , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Piperidinas/farmacologia , Verapamil/farmacologia
12.
Anticancer Res ; 39(12): 6499-6505, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810914

RESUMO

BACKGROUND/AIM: Development of new potential drugs to overcome multidrug resistance to chemotherapy is a big challenge for cancer treatment. Attention is also given to the natural compounds and their derivatives. The study aimed at evaluating the impact of a new chalcone derivative (1C) on multidrug resistant cell lines, focusing on P-glycoprotein (P-gp, ABCB1) inhibition, as well as 1C-doxorubicin interaction in vitro. MATERIALS AND METHODS: Cytotoxic and antiproliferative effects of the 1C compound were assessed by thiazolyl blue tetrazolium bromide (MTT) method in mouse T-cell lymphoma and human colon adenocarcinoma cells expressing ABCB1. Alterations in ABCB1 activity were evaluated by rhodamine 123 accumulation assay using flow cytometry. Drug-drug interaction was studied using combination assay. RESULTS: Our results confirmed antiproliferative, cytotoxic, as well as ABCB1 inhibitory potential of 1C in both tested ABCB1-expressing cancer cell lines. Furthermore, 1C displayed synergistic interaction with doxorubicin. CONCLUSION: Our results suggest the 1C chalcone derivative as a promising compound against resistant lymphoma and colon cancer, which could be used in monotherapy or in combination with other chemotherapeutics.


Assuntos
Adenocarcinoma/metabolismo , Chalconas/farmacologia , Neoplasias do Colo/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Linfoma de Células T/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Adenocarcinoma/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Regulação para Baixo , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Linfoma de Células T/tratamento farmacológico
13.
Curr Med Sci ; 39(6): 1003-1008, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31845234

RESUMO

Human beings are increasingly exposed to phthalates, which are a group of chemicals used to make plastics more flexible and harder to break, and simultaneously ingesting abundant food emulsifiers via daily diet. The purpose of this study was to investigate the effect of the food emulsifier glycerin monostearate (GMS) on male reproductive toxicity caused by di(2-ethylhexyl) phthalate (DEHP, one of the phthalates) and explore the underlying mechanism. Thirty male Sprague-Dawley rats were randomly divided into control group, DEHP group and DEHP+GMS group. Rats in the DEHP group and DEHP+GMS group were orally administered with 200 mg/kg/d DEHP with or without 20 mg/kg/d GMS. After 30 days of continuous intervention, it was found that the serum testosterone level was significantly lowered in DEHP group and DEHP+GMS group than that in control group (P<0.01). The serum testosterone level and the relative testis weight were significantly decreased in the DEHP+GMS group as compared with those in the DEHP group and control group (P<0.05). More spermatids were observed to be shed off in DEHP+GMS group than in DEHP group. The expression levels of cell cycle checkpoint kinase 1 (Chk1), cell division cycle gene 2 (Cdc2), and cyclin-dependent kinase 2 (CDK2) were down-regulated in DEHP group, and this tendency was more significant in DEHP+GMS group (P<0.05 or P<0.01). There was no significant difference in the P-glycoprotein (P-gp) expression between DEHP group and control group. However, P-gp was markedly down-regulated in DEHP+GMS group (P<0.01). The results indicated that the food emulsifier GMS aggravated the toxicity of DEHP on male reproduction by inhibiting the cell cycle of testicular cells and the expression of P-gp in testis tissues.


Assuntos
Dietilexilftalato/toxicidade , Emulsificantes/toxicidade , Glicerol/toxicidade , Reprodução/efeitos dos fármacos , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Administração Oral , Animais , Proteína Quinase CDC2/metabolismo , Quinase 1 do Ponto de Checagem/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Dietilexilftalato/administração & dosagem , Regulação para Baixo , Emulsificantes/administração & dosagem , Glicerol/administração & dosagem , Masculino , Tamanho do Órgão/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Testículo/efeitos dos fármacos , Testosterona/sangue
14.
Dis Markers ; 2019: 1343650, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31871496

RESUMO

Background: Epilepsy is one of the most common neurological disorders with about 30% treatment failure rate. An interindividual variations in efficacy of antiepileptic drugs (AEDs) make the treatment of epilepsy challenging, which can be attributed to genetic factors such as ATP-Binding Cassette sub-family B, member1 (ABCB1) gene polymorphisms. Objective: The main objective of the present study is to evaluate the association of ABCB1 C1236T, G2677T, and C3435T polymorphisms with treatment response among Tunisian epileptic patients. Materials and Methods: One hundred epileptic patients, originated from north of Tunisia, were recruited and categorized into 50 drug-resistant and 50 drug-responsive patients treated with antiepileptic drugs (AEDs) as per the International League Against Epilepsy. DNA of patients was extracted and ABCB1 gene polymorphisms studied using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results: The C1236T, G2677T, and C3435T polymorphisms were involved into AED resistance. Significant genotypic (C1236T TT (p ≤ 0.001); G2677T TT (p = 0.001); C3435T TT (p ≤ 0.001)) and allelic associations (C1236T T (3.650, p ≤ 0.001); G2677TT (1.801, p = 0.044); C3435T T (4.730, p ≤ 0.001)) with drug resistance epilepsy (DRE) were observed. A significant level of linkage disequilibrium (LD) was also noted between ABCB1 polymorphisms. Patients with the haplotypes CT and TT (C1236T-G2677T); GT, TC, and TT (G2677T-C3435T); CT and TT (C1236T-C3435T); CTT, TTC, TGT, and TTT (C1236T-G2677T-C3435T) were also significantly associated to AED resistance. Conclusions: The response to antiepileptics seems to be modulated by TT genotypes, T alleles, and the predicted haplotypes for the tested SNPs in our population. Genetic analysis is a valuable tool for predicting treatment response and thus will contribute to personalized medicine for Tunisian epileptic patients.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Polimorfismo de Fragmento de Restrição , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Idade de Início , Estudos de Casos e Controles , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/genética , Feminino , Estudos de Associação Genética , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Tunísia
15.
BMC Plant Biol ; 19(1): 589, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881837

RESUMO

BACKGROUND: Short internodes contribute to plant dwarfism, which is exceedingly beneficial for crop production. However, the underlying mechanisms of internode elongation are complicated and have been not fully understood. RESULTS: Here, we report a maize dwarf mutant, dwarf2014 (d2014), which displays shortened lower internodes. Map-based cloning revealed that the d2014 gene is a novel br2 allele with a splicing variation, resulting in a higher expression of BR2-T02 instead of normal BR2-T01. Then, we found that the internode elongation in d2014/br2 exhibited a pattern of inhibition-normality-inhibition (transient for the ear-internode), correspondingly, at the 6-leaf, 12-leaf and 14-leaf stages. Indeed, BR2 encodes a P-glycoprotein1 (PGP1) protein that functions in auxin efflux, and our in situ hybridization assay showed that BR2 was mainly expressed in vascular bundles of the node and internode. Furthermore, significantly higher auxin concentration was detected in the stem apex of d2014 at the 6-leaf stage and strictly in the node region for the ear-internode at the 14-leaf stage. In such context, we propose that BR2/PGP1 transports auxin from node to internode through the vascular bundles, and excessive auxin accumulation in the node (immediately next to the intercalary meristem) region suppresses internode elongation of d2014. CONCLUSIONS: These findings suggest that low auxin levels mediated by BR2/PGP1 in the intercalary meristem region are crucial for internode elongation.


Assuntos
Ácidos Indolacéticos/metabolismo , Meristema/metabolismo , Proteínas de Plantas/fisiologia , Zea mays/crescimento & desenvolvimento , Subfamília B de Transportador de Cassetes de Ligação de ATP/fisiologia , Alelos , Transporte Biológico , Isoformas de Proteínas , Zea mays/genética , Zea mays/metabolismo
16.
Biomed Res Int ; 2019: 1269532, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31871929

RESUMO

Multidrug resistance is the main obstacle to current chemotherapies. In this study, we evaluated the reversing effect of matrine, the principal alkaloid derived from Sophora alopecuroides, on chemoresistant leukemia K562/ADR cells. Matrine in a range of the nontoxic concentration was employed in the whole study. IC50s of cancer medicines were tested using WST-8 assay. Drug export and apoptotic rates were examined using flow cytometry. The mRNA and protein expressions were quantified by quantitative real-time PCR and western blotting, respectively. Our data indicated that matrine had potent reversal properties augmenting cytotoxicity of cancer medicines on K562/ADR cells as well as apoptotic rates induced by doxorubicin. Moreover, matrine inhibited drug-exporting activity and expression of ATP-binding cassette subfamily B member 1 (ABCB1) on both mRNA and protein levels. That might result from inhibited NF-kappa B activation, which also led to restored intrinsic apoptosis. These findings suggest that matrine in the nontoxic concentration can suppress ABCB1 drug transport and facilitate the intrinsic apoptosis pathway through the inhibiting effect on NF-kappa B and has the potential to become an efficient sensitizer for anticancer drug resistance.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Células K562/efeitos dos fármacos , Quinolizinas/farmacologia , Sophora/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Humanos , Concentração Inibidora 50 , Leucemia/tratamento farmacológico , NF-kappa B/antagonistas & inibidores
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(5): 595-600, 2019 Oct 30.
Artigo em Chinês | MEDLINE | ID: mdl-31699188

RESUMO

Objective To explore the role of multidrug resistance gene-1(MDR1)gene in methotrexate(MTX)resistance in patients with rheumatoid arthritis(RA).Methods Fibroblast-like synoviocytes(FLS)from RA patients were infected with recombinant adenovirus Ad-EGFP-MDR1 in vitro to obtain MDR1 over-expressed RA FLS.The transcription level of MDR1 gene and the expression level of its coding product P-glycoprotein(P-gp) rotein were detected by real-time PCR and Western blot analysis.The efflux function was verified by rhodamine 123 efflux assay.The resistance to MTX was detected by MTT assay.Results RA FLS were infected with recombinant adenovirus Ad-EGFP-MDR1;72 hours later,the particles size in MDR1 over-expressed RA FLS increased,the cell volume became larger,and the growth rate decreased.The transcription level of MDR1(1.4325±0.3924 vs.0.0650±0.0070;t=6.035,P=0.004),the expression level of P-gp protein(1.8667±0.2857 vs. 0.9367±0.0551;t=5.536,P=0.005),and the ability of extracellular rhodamine 123(979.43±196.81 vs.1680.06±147.04;t=-4.940,P=0.008) in MDR1 over-expressed RA FLS were significantly higher than those of negative virus control RA-FLS,and the survival rate of MDR1 over-expressed RA FLS was significantly increased at each concentration of MTX(P<0.05).Conclusion The high expression of MDR1 can affect the efflux ability to MTX by up-regulating the expression of P-gp,thus enhancing the drug resistance to MTX in RA FLS.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Resistência a Medicamentos , Fibroblastos/efeitos dos fármacos , Metotrexato/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Artrite Reumatoide/genética , Células Cultivadas , Humanos , Membrana Sinovial/citologia
18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(11): 1073-1076, 2019 Nov 10.
Artigo em Chinês | MEDLINE | ID: mdl-31703128

RESUMO

OBJECTIVE: To assess the association of single nucleotide polymorphisms of multidrug resistance gene 1 (MDR1) with refractory epilepsy in children. METHODS: Peripheral blood samples were collected from 200 children with epilepsy and 100 healthy controls. Genomic DNA was extracted and subjected to PCR amplification, agarose gel electrophoresis and target site sequencing. Genotypes of rs1922242, rs2235048, rs10808072, rs868755 and rs1202184 loci of the MDR1 gene were analyzed. RESULTS: No significant difference was found in genotypic distribution and allelic frequencies of the rs1922242, rs2235048, rs10808072 and rs868755 loci between the drug-resistant and drug-sensitive groups. For the rs1202184 locus, a significant difference in genotypic distribution was found (P=0.008). No significant difference was found in the frequencies of various haplotypes between the two groups. CONCLUSION: Genotypes of the rs1202184 locus of the MDR1 gene are associated with refractory epilepsy in children, for which the AA genotype plays a dominant role.


Assuntos
Epilepsia Resistente a Medicamentos/genética , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Estudos de Casos e Controles , Criança , Frequência do Gene , Genótipo , Haplótipos , Humanos
19.
Anticancer Res ; 39(10): 5461-5471, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570440

RESUMO

BACKGROUND/AIM: Multidrug resistance (MDR) is often associated with overexpression of P-glycoprotein (ABCB1) in cancer cells. Apatinib is a novel Vascular endothelial growth factor receptor-TKI (VEGFR-TKI) which inhibits the function of ABCB1 in certain cancers. This study aimed to investigate the effect of apatinib on the reversal of paclitaxel (PTX) resistance in A549 lung cancer cells (A549/PTX) and related mechanisms. MATERIALS AND METHODS: A549/PTX cells were treated with apatinib alone, PTX alone, or PTX and apatinib. Cell viability was measured by the CCK8 assay. Apoptosis rate, cell-cycle arrest, Rhodamine efflux and reactive oxygen species (ROS) generation were determined by flow cytometry. The intracellular paclitaxel concentration was measured by ultra performance liquid chromatography (UPLC). Protein levels were analyzed by western blotting. RESULTS: A549/PTX cells had significant resistance to PTX and higher expression of ABCB1 compared to A549 cells. Apatinib increased the cytotoxicity of PTX, enhanced PTX-induced apoptosis and cycle arrest, and triggered intracellular ROS generation in A549/PTX cells. In addition, apatinib treatment increased the concentration of intracellular PTX in A549/PTX cells. Apatinib-PTX combination inhibited AKT and ERK pathways. CONCLUSION: Apatinib reverses the drug resistance to PTX in A549 PTX-resistant cells through inhibiting the function of ABCB1 and resumes anti-cancer effects.


Assuntos
Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Piridinas/farmacologia , Células A549 , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Espécies Reativas de Oxigênio/metabolismo
20.
Life Sci ; 238: 116938, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31593704

RESUMO

AIMS: To investigate the effect of 7-O-geranylquercetin (GQ), a derivative of quercetin (Q), on reversing drug resistance in breast cancer MCF-7/ADR cells and reveal the mechanisms related to P-glycoprotein (P-gp). MAIN METHODS: Cell viability was determined by MTT assay. Accumulation of adriamycin (ADR) in cells was determined by confocal fluorescence microscope and microplate reader while that of rhodamine (Rh) was measured by flow cytometry. Expression levels of P-gp and MDR1 gene in cells were detected by western blot and Real-Time PCR, respectively. Molecular docking of GQ and Q with P-gp was conducted using AutoDock program. Xenograft model was established by inoculating MCF-7/ADR cells in BALB/c-nude mice. Tumor bearing mice were administered with ADR via tail vein injection and/or GQ (Q) by gavage. Expression levels of P-gp in tissues were detected by western blot and immunohistochemistry. KEY FINDINGS: GQ could reverse drug resistance of MCF-7/ADR cells to ADR. GQ inhibited the efflux of ADR by down-regulating the expression of P-gp protein and its encoding gene MDR1 in MCF-7/ADR cells. Molecular modeling showed that GQ matched with P-gp better than Q. GQ enhanced the antitumor effects of ADR and decreased the expression of P-gp in mice and its activities were higher than that of Q. GQ could reverse drug resistance of MCF-7/ADR cells by down-regulating the expression of P-gp in vitro and in vivo. SIGNIFICANCES: The reversal effect of GQ on P-gp-mediated drug resistance indicates its potential as a reversal agent for drug resistance in cancer chemotherapy.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Quercetina/análogos & derivados , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Antibióticos Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Quercetina/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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