The ATP-binding cassette (ABC) superfamily of active transporters involves a large number of functionally diverse transmembrane proteins. They transport a variety of substrates including amino acids, lipids, inorganic ions, peptides, saccharides, metals, drugs, and proteins. The ABC transporters not only move a variety of substrates into and out of the cell, but also are also involved in intracellular compartmental transport. Energy derived from the hydrolysis of ATP is used to transport the substrate across the membrane against a concentration gradient. The typical ABC transporter consists of two transmembrane domains and two nucleotide-binding domains. Defects in 14 of these transporters cause 13 genetic diseases (cystic fibrosis, Stargardt disease, adrenoleukodystrophy, Tangier disease, etc.). Mutations in three genes affect lipid levels expressively. Mutations in ABCA1 cause severe HDL deficiency syndromes called Tangier disease and familial high-density lipoprotein deficiency, which are characterized by a severe deficiency or absence of high-density lipoprotein in the plasma. Two other ABCG transporters, ABCG5 and ABCG8, mutations of which cause sitosterolemia, have been identified. The affected individuals absorb and retain plant sterols, as well as shellfish sterols.

• MeSH
• ABC transportéry chemie   klasifikace   genetika   metabolismus   MeSH
• adenosintrifosfát metabolismus   MeSH
• energetický metabolismus genetika   MeSH
• hydrolýza MeSH
• lidé MeSH
• metabolismus lipidů * MeSH
• vrozené poruchy metabolismu genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• ABC transportéry MeSH
• adenosintrifosfát MeSH

The prognosis of esophageal cancer (EC) is poor, despite considerable effort of both experimental scientists and clinicians. The tri-modality treatment consisting of neoadjuvant chemoradiation followed by surgery has remained the gold standard over decades, unfortunately, without significant progress in recent years. Suitable prognostic factors indicating which patients will benefit from this tri-modality treatment are missing. Some patients rapidly progress on the neoadjuvant chemoradiotherapy, which is thus useless and sometimes even harmful. At the same time, other patients achieve complete remission on neoadjuvant chemoradiotherapy and subsequent surgery may increase their risk of morbidity and mortality. The prognosis of patients ranges from excellent to extremely poor. Considering these differences, the role of drug metabolizing enzymes and transporters, among other factors, in the EC response to chemotherapy may be more important compared, for example, with pancreatic cancer where all patients progress on chemotherapy regardless of the treatment or disease stage. This review surveys published literature describing the potential role of ATP-binding cassette transporters, the genetic polymorphisms, epigenetic regulations, and phenotypic changes in the prognosis and therapy of EC. The review provides knowledge base for further research of potential predictive biomarkers that will allow the stratification of patients into defined groups for optimal therapeutic outcome.

• Klíčová slova
• ABC transporters, biomarker, cancer, chemotherapy, esophagus, prognosis, radiotherapy,
• MeSH
• ABC transportéry genetika   metabolismus   MeSH
• epigeneze genetická MeSH
• lidé MeSH
• nádorové biomarkery genetika   metabolismus   MeSH
• nádory jícnu genetika   metabolismus   terapie   MeSH
• neoadjuvantní terapie metody   MeSH
• polymorfismus genetický MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• ABC transportéry MeSH
• nádorové biomarkery MeSH

Maraviroc is a chemokine receptor 5 (CCR5) inhibitor used in the treatment of human immunodeficiency virus (HIV) that also shows therapeutic potential for several autoimmune, cancer, and inflammatory diseases that can afflict pregnant women. However, only limited information exists on the mechanisms underlying the transplacental transfer of the drug. We aimed to expand the current knowledge base on how maraviroc interacts with several placental ATP-binding cassette (ABC) efflux transporters that have a recognized role in the protection of a developing fetus: P-glycoprotein (ABCB1), breast cancer resistance protein (ABCG2), and multidrug resistance protein 2 (ABCC2). We found that maraviroc does not inhibit any of the three studied ABC transporters and that its permeability is not affected by ABCG2 or ABCC2. However, our in vitro results revealed that maraviroc shows affinity for human ABCB1 and the endogenous canine P-glycoprotein (Abcb1) expressed in Madin-Darby canine kidney II (MDCKII) cells. Perfusion of rat term placenta showed accelerated transport of maraviroc in the fetal-to-maternal direction, which suggests that ABCB1/Abcb1 facilitates in situ maraviroc transport. This transplacental transport was saturable and significantly diminished after the addition of the ABCB1/Abcb1 inhibitors elacridar, zosuquidar, and ritonavir. Our results indicate that neither ABCG2 nor ABCC2 influence maraviroc pharmacokinetic but that ABCB1/Abcb1 may be partly responsible for the decreased transplacental permeability of maraviroc to the fetus. The strong affinity of maraviroc to Abcb1 found in our animal models necessitates studies in human tissue so that maraviroc pharmacokinetics in pregnant women can be fully understood. SIGNIFICANCE STATEMENT: Antiretroviral drug maraviroc shows low toxicity and is thus a good candidate for prevention of mother-to-child transmission of human immunodeficiency virus when failure of recommended therapy occurs. Using in vitro cell-based experiments and in situ dually perfused rat term placenta, we examined maraviroc interaction with the placental ABC drug transporters ABCB1, ABCG2, and ABCC2. We demonstrate for the first time that placental ABCB1 significantly reduces mother-to-fetus transport of maraviroc, which suggests that ABCB1 may be responsible for the low cord-blood/maternal-blood ratio observed in humans.

• MeSH
• ABC transportér z rodiny G, člen 2 metabolismus   MeSH
• antagonisté receptoru CCR5 farmakokinetika   terapeutické užití   MeSH
• buňky MDCK MeSH
• HIV infekce farmakoterapie   MeSH
• infekční komplikace v těhotenství farmakoterapie   MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• maravirok farmakokinetika   terapeutické užití   MeSH
• maternofetální výměna látek * MeSH
• modely u zvířat MeSH
• P-glykoprotein metabolismus   MeSH
• permeabilita MeSH
• placenta metabolismus   MeSH
• placentární oběh MeSH
• plod metabolismus   MeSH
• protein spojený s mnohočetnou rezistencí k lékům 2 MeSH
• proteiny spojené s mnohočetnou rezistencí k lékům metabolismus   MeSH
• psi MeSH
• těhotenství MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• psi MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ABC transportér z rodiny G, člen 2 MeSH
• ABCC2 protein, human MeSH Prohlížeč
• antagonisté receptoru CCR5 MeSH
• maravirok MeSH
• P-glykoprotein MeSH
• protein spojený s mnohočetnou rezistencí k lékům 2 MeSH
• proteiny spojené s mnohočetnou rezistencí k lékům MeSH

Colorectal cancer, one of the most frequent types of cancer worldwide, has a high mortality rate. Irinotecan (CPT-11) has been approved for the treatment of advanced or metastatic disease either as a single agent or, more commonly, as part of combined chemotherapeutic regimens. Treatment with irinotecan is often accompanied by severe toxicity (e.g. neutropenia and diarrhea) that can result in treatment interruption or cessation, thus jeopardizing the patient's prognosis and quality of life. Irinotecan is bioactivated into its metabolite SN-38, which is subsequently detoxified by uridine diphosphate-glucuronosyl transferases (mainly UGT1A1). Further, ABC transporters (i.e. ABCB1, ABCC1-ABCC6, and ABCG2) are responsible for drug efflux into bile and urine whereas OATP transporters (SLCO1B1) enable its influx from blood into hepatocytes. Genetic polymorphisms in these enzymes/pumps may result in increased systemic SN-38 level, directly correlating with toxicity. Contemporary research is focused on the clinical implementation of genetic screenings for validated gene variations prior to treatment onset, allowing tailored individual doses or treatment regimens.

• Klíčová slova
• ABC transporters, SLCO1B1, UGT1A1*28, diarrhea, irinotecan, neutropenia,
• MeSH
• ABC transportéry genetika   MeSH
• farmakogenetika trendy   MeSH
• genotyp MeSH
• glukuronosyltransferasa genetika   MeSH
• individualizovaná medicína trendy   MeSH
• irinotekan škodlivé účinky   terapeutické užití   MeSH
• jednonukleotidový polymorfismus genetika   MeSH
• kolorektální nádory farmakoterapie   genetika   MeSH
• lidé MeSH
• metabolická inaktivace genetika   MeSH
• nežádoucí účinky léčiv genetika   patologie   MeSH
• polypeptid C přenášející organické anionty genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• ABC transportéry MeSH
• glukuronosyltransferasa MeSH
• irinotekan MeSH
• polypeptid C přenášející organické anionty MeSH
• SLCO1B1 protein, human MeSH Prohlížeč
• UGT1A1 enzyme MeSH Prohlížeč

Hyperuricemia depends on the balance of endogenous production and renal excretion of uric acid. Transporters for urate are located in the proximal tubule where uric acid is secreted and extensively reabsorbed: secretion is principally ensured by the highly variable ABCG2 gene. Enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT) plays a central role in purine metabolism and its deficiency is an X-linked inherited metabolic disorder associated with clinical manifestations of purine overproduction. Here we report the case of a middle-aged man with severe chronic tophaceous gout with a poor response to allopurinol and requiring repeated surgical intervention. We identified the causal mutations in the HPRT1 gene, variant c.481G>T (p.A161S), and in the crucial urate transporter ABCG2, a heterozygous variant c.421C>A (p.Q141K). This case shows the value of an analysis of the genetic background of serum uric acid.

• Klíčová slova
• ABCG2, Gout, Hyperuricemia, Hypoxanthine-guanine phosphoribosyltransferase deficiency, Tophi, Urate transporter,
• MeSH
• ABC transportér z rodiny G, člen 2 genetika   MeSH
• chronická nemoc MeSH
• dna (nemoc) genetika   metabolismus   MeSH
• genetické pozadí * MeSH
• hypoxanthinfosforibosyltransferasa nedostatek   genetika   metabolismus   MeSH
• kyselina močová metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mutace MeSH
• nádorové proteiny genetika   MeSH
• přenašeče organických aniontů genetika   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• ABC transportér z rodiny G, člen 2 MeSH
• ABCG2 protein, human MeSH Prohlížeč
• hypoxanthinfosforibosyltransferasa MeSH
• kyselina močová MeSH
• nádorové proteiny MeSH
• přenašeče organických aniontů MeSH
• urate transporter MeSH Prohlížeč

INTRODUCTION: Progressive familial intrahepatic cholestasis type 3 (PFIC3) is a rare autosomal recessive cholestatic liver disorder caused by genetic deficiency of ATP-binding cassette subfamily B member 4 (ABCB4), a hepatocanalicular floppase translocating phospholipids from the inner to the outer leaflet of the canalicular membrane lipid bilayer. PFIC3 is characterised by production of hydrophilic bile with lithogenic properties which is harmful to the hepatobiliary epithelia. Chronic cholestasis in some patients may be accompanied by excessive accumulation of copper in the liver and by increased urinary copper excretion, the findings mimicking Wilson disease (WD). METHODS AND RESULTS: We report an 11 y/o male patient with growth retardation, mild craniofacial dysmorphic features and chronic liver disease, initially diagnosed and treated as WD. Whereas genetic testing for WD was negative, further molecular and histopathological analysis revealed two novel mutations (c.833+1G>T and c.1798T>A) in ABCB4 and complete absence of the ABCB4/MDR3 protein in the liver, determining PFIC3 as the correct diagnosis. CONCLUSION: PFIC3 and WD display pleomorphic and sometimes overlapping clinical and laboratory features, which may pose a differential diagnostic problem. Since the patient management in WD and PFIC3 differs significantly, an early and accurate diagnosis is crucial for optimising of therapeutic approach and prevention of possible complications.

• Klíčová slova
• ABCB4, ATP7B, Wilson disease, copper metabolism, progressive familial intrahepatic cholestasis type 3,
• MeSH
• diferenciální diagnóza MeSH
• dítě MeSH
• hepatolentikulární degenerace diagnóza   MeSH
• intrahepatální cholestáza diagnóza   MeSH
• lidé MeSH
• P-glykoproteiny nedostatek   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• P-glykoproteiny MeSH

Leflunomide (LEF) is a disease-modifying anti-rheumatic drug used for treating rheumatoid arthritis (RA). More than 50% of patients are withdrawn from LEF treatment within one year, mainly due to AEs. Importantly, it is not possible to predict which patients will respond to LEF therapy nor if adverse outcome occurs. Pharmacogenetic studies indicate an impact of single nucleotid polymorphisms (SNPs) on the variability in LEF serum levels with potential relevance to effectiveness and tolerability in individual RA patients. In vitro studies have demonstrated that cytochromes P450 (CYPs), mainly CYP1A2, CYP2C19, and CYP3A4, are involved in LEF metabolite activation. It was shown that CYP1A2*1F allele may be associated with LEF toxicity in patients with RA. In case of dihydroorotate dehydrogenase (DHODH) gene SNP (rs3213422, 19C>A), it was shown that C allele may be associated with LEF toxicity and therapeutic effect. Finally, oestrogen receptor genes SNPs in females may be associated with LEF therapy efficacy. In summary, the results of the current studies suggest a possible diagnostic value of genotyping for patients with RA as biomarkers of LEF therapy efficacy or conversely as indicators of serious side effects. In the future, it will be necessary to corroborate these results in studies with larger numbers of patients and longer follow-up. Moreover, it would be appropriate to focus on CYP2C19, ATP5A1 and PKD1L3 genes.

• MeSH
• ABC transportér z rodiny G, člen 2 MeSH
• ABC transportéry genetika   metabolismus   MeSH
• antirevmatika škodlivé účinky   farmakokinetika   MeSH
• biotransformace genetika   MeSH
• dihydroorotátdehydrogenasa MeSH
• farmakogenetika MeSH
• fenotyp MeSH
• genotyp MeSH
• isoxazoly škodlivé účinky   farmakokinetika   MeSH
• izoenzymy MeSH
• jednonukleotidový polymorfismus * MeSH
• leflunomid MeSH
• lidé MeSH
• nádorové proteiny genetika   metabolismus   MeSH
• oxidoreduktasy působící na CH-CH vazby genetika   metabolismus   MeSH
• receptory pro estrogeny genetika   metabolismus   MeSH
• revmatoidní artritida diagnóza   farmakoterapie   MeSH
• rizikové faktory MeSH
• systém (enzymů) cytochromů P-450 genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• ABC transportér z rodiny G, člen 2 MeSH
• ABC transportéry MeSH
• ABCG2 protein, human MeSH Prohlížeč
• antirevmatika MeSH
• dihydroorotátdehydrogenasa MeSH
• isoxazoly MeSH
• izoenzymy MeSH
• leflunomid MeSH
• nádorové proteiny MeSH
• oxidoreduktasy působící na CH-CH vazby MeSH
• receptory pro estrogeny MeSH
• systém (enzymů) cytochromů P-450 MeSH

Human papillomavirus (HPV) is responsible for cervical cancer, and its role in head and neck carcinoma has been reported. No drug is approved for the treatment of HPV-related diseases but cidofovir (CDV) exhibits selective antiproliferative activity. In this study, we analyzed the effects of CDV-resistance (CDVR) in two HPV(+) (SiHaCDV and HeLaCDV) and one HPV(-) (HaCaTCDV) tumor cell lines. Quantification of CDV metabolites and analysis of the sensitivity profile to chemotherapeutics was performed. Transporters expression related to multidrug-resistance (MRP2, P-gp, BCRP) was also investigated. Alterations of CDV metabolism in SiHaCDV and HeLaCDV, but not in HaCaTCDV, emerged via impairment of UMP/CMPK1 activity. Mutations (P64T and R134M) as well as down-regulation of UMP/CMPK1 expression were observed in SiHaCDV and HeLaCDV, respectively. Altered transporters expression in SiHaCDV and/or HeLaCDV, but not in HaCaTCDV, was also noted. Taken together, these results indicate that CDVR in HPV(+) tumor cells is a multifactorial process.

• Klíčová slova
• NTP metabolism, UMP-CMP kinase, cervical carcinoma, cidofovir, human papillomavirus,
• MeSH
• ABC transportéry biosyntéza   MeSH
• chemorezistence genetika   MeSH
• cidofovir MeSH
• cytidintrifosfát biosyntéza   MeSH
• cytosin analogy a deriváty   farmakologie   MeSH
• fosforylace MeSH
• HeLa buňky MeSH
• infekce papilomavirem farmakoterapie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• nádorové buněčné linie MeSH
• nádory děložního čípku farmakoterapie   patologie   virologie   MeSH
• nukleosidmonofosfátkinasa biosyntéza   metabolismus   MeSH
• organofosfonáty farmakologie   MeSH
• Papillomaviridae MeSH
• SLC transportéry biosyntéza   MeSH
• uridintrifosfát biosyntéza   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ABC transportéry MeSH
• cidofovir MeSH
• cytidintrifosfát MeSH
• cytidylate kinase MeSH Prohlížeč
• cytosin MeSH
• nukleosidmonofosfátkinasa MeSH
• organofosfonáty MeSH
• SLC transportéry MeSH
• uridintrifosfát MeSH

The interplays between the metabolic products of intestinal microbiota and the host signaling through xenobiotic receptors, including pregnane X receptor (PXR), are of growing interest, in the context of intestinal health and disease. A distinct class of microbial catabolites is formed from dietary tryptophan, having the indole scaffold in their core structure, which is a biologically active entity. In the current study, we examined a series of ten tryptophan microbial catabolites for their interactions with PXR signaling. Utilizing a reporter gene assay, we identified indole (IND) and indole-3-acetamide (IAD) as PXR agonists. IND and IAD induced PXR-regulated genes CYP3A4 and MDR1 in human intestinal cancer cells. Using time-resolved fluorescence resonance energy transfer, we show that IND (IC50 292 μM) and IAD (IC50 10 μM) are orthosteric ligands of PXR. Binding of PXR in its DNA response elements was enhanced by IND and IAD, as revealed by chromatin immunoprecipitation assay. We demonstrate that tryptophan microbial intestinal metabolites IND and IAD are ligands and agonists of human PXR. These findings are of particular importance in understanding the roles of microbial catabolites in human physiology and pathophysiology. Furthermore, these results are seminal in expanding potential drug repertoire through microbial metabolic mimicry.

• Klíčová slova
• Indole metabolites, Intestinal health, Microbial catabolism, Pregnane X receptor,
• MeSH
• cytochrom P-450 CYP3A genetika   metabolismus   MeSH
• indoly metabolismus   MeSH
• kultivované buňky MeSH
• kyseliny indoloctové metabolismus   MeSH
• lidé MeSH
• ligandy MeSH
• nádorové buněčné linie MeSH
• P-glykoproteiny genetika   metabolismus   MeSH
• pregnanový X receptor agonisté   genetika   MeSH
• reportérové geny MeSH
• střevní mikroflóra * MeSH
• střevní sliznice * metabolismus   mikrobiologie   MeSH
• transfekce MeSH
• tryptofan metabolismus   MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ABCB1 protein, human MeSH Prohlížeč
• CYP3A4 protein, human MeSH Prohlížeč
• cytochrom P-450 CYP3A MeSH
• indole MeSH Prohlížeč
• indoleacetamide MeSH Prohlížeč
• indoly MeSH
• kyseliny indoloctové MeSH
• ligandy MeSH
• P-glykoproteiny MeSH
• pregnanový X receptor MeSH
• tryptofan MeSH

Elevated serum urate levels cause gout and correlate with cardiometabolic diseases via poorly understood mechanisms. We performed a trans-ancestry genome-wide association study of serum urate in 457,690 individuals, identifying 183 loci (147 previously unknown) that improve the prediction of gout in an independent cohort of 334,880 individuals. Serum urate showed significant genetic correlations with many cardiometabolic traits, with genetic causality analyses supporting a substantial role for pleiotropy. Enrichment analysis, fine-mapping of urate-associated loci and colocalization with gene expression in 47 tissues implicated the kidney and liver as the main target organs and prioritized potentially causal genes and variants, including the transcriptional master regulators in the liver and kidney, HNF1A and HNF4A. Experimental validation showed that HNF4A transactivated the promoter of ABCG2, encoding a major urate transporter, in kidney cells, and that HNF4A p.Thr139Ile is a functional variant. Transcriptional coregulation within and across organs may be a general mechanism underlying the observed pleiotropy between urate and cardiometabolic traits.

• MeSH
• ABC transportér z rodiny G, člen 2 genetika   MeSH
• celogenomová asociační studie MeSH
• dna (nemoc) krev   epidemiologie   genetika   MeSH
• genetická predispozice k nemoci MeSH
• genetické lokusy MeSH
• genetické markery * MeSH
• hepatocytární jaderný faktor 1-alfa genetika   MeSH
• hepatocytární jaderný faktor 4 genetika   MeSH
• játra metabolismus   patologie   MeSH
• jednonukleotidový polymorfismus * MeSH
• kardiovaskulární nemoci krev   epidemiologie   genetika   MeSH
• kohortové studie MeSH
• kyselina močová krev   MeSH
• ledviny metabolismus   patologie   MeSH
• lidé MeSH
• metabolické nemoci krev   epidemiologie   genetika   MeSH
• nádorové proteiny genetika   MeSH
• orgánová specificita MeSH
• signální transdukce * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ABC transportér z rodiny G, člen 2 MeSH
• ABCG2 protein, human MeSH Prohlížeč
• genetické markery * MeSH
• hepatocytární jaderný faktor 1-alfa MeSH
• hepatocytární jaderný faktor 4 MeSH
• HNF1A protein, human MeSH Prohlížeč
• HNF4A protein, human MeSH Prohlížeč
• kyselina močová MeSH
• nádorové proteiny MeSH