Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P33527 (ABCC1)
 1,164 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Multidrug resistance protein 1 (MRP1/ABCC1) is an ATP-dependent polytopic membrane protein that transports many anticancer drugs and organic anions. Its transport mechanism is multifaceted, especially with respect to the participation of GSH. For example, vincristine is cotransported with GSH, estrone sulfate transport is stimulated by GSH, or MRP1 can transport GSH alone, and this can be stimulated by compounds such as verapamil or apigenin. Thus, the interactions between GSH and MRP1 are mechanistically complex. To examine the similarities and differences among the various GSH-associated mechanisms of MRP1 transport, we have measured first the effect of GSH and several GSH-associated substrates/modulators on the binding and hydrolysis of ATP by MRP1 using 8-azidoadenosine-5'-[(32)P]-triphosphate ([(32)P]azidoATP) analogs, and second the initial binding of GSH and GSH-associated substrates/modulators to MRP1. We observed that GSH or its nonreducing derivative S-methylGSH (S-mGSH), but none of the GSH-associated substrate/modulators, caused a significant increase in [gamma-(32)P]azidoATP labeling of MRP1. Moreover, GSH and S-mGSH decreased levels of orthovanadate-induced trapping of [alpha-(32)P]azidoADP. [alpha-(32)P]azidoADP.Vi trapping was also decreased by estone sulfate, whereas vincristine, verapamil, and apigenin had no apparent effects on nucleotide interactions with MRP1. Furthermore, estrone sulfate and S-mGSH enhanced the effect of each other 15- and 10-fold, respectively. Second, although GSH binding increased the apparent affinity of MRP1 for all GSH-associated substrates/modulators tested, only estrone sulfate had a reciprocal effect on the apparent affinity of MRP1 for GSH. Overall, these results indicate significant mechanistic differences between MRP1-mediated transport of GSH and the ability of GSH to modulate MRP1 transport.
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PMID:Mechanistic differences between GSH transport by multidrug resistance protein 1 (MRP1/ABCC1) and GSH modulation of MRP1-mediated transport. 1876 87

Sunitinib malate (Sutent, SU11248) is a small-molecule receptor tyrosine kinase inhibitor that inhibits cellular signaling of multiple targets such as the platelet-derived growth factor receptors and the vascular endothelial growth factor receptors and is used in the treatment of renal cell carcinoma and imatinib-resistant gastrointestinal stromal tumors. Because tyrosine kinase inhibitors are known to increase the p.o. bioavailability and brain penetration of chemotherapy drugs in animal models, we sought to examine the effect of sunitinib on the ATP-binding cassette (ABC) drug transporters P-glycoprotein (P-gp, ABCB1), the multidrug resistance-associated protein 1 (ABCC1), and ABCG2, which are known to transport a wide variety of anticancer drugs. In this study, we show that sunitinib inhibits P-gp- and ABCG2-mediated efflux of fluorescent substrates in cells overexpressing these transporters. In 4-day cytotoxicity assays, at a nontoxic concentration (2 microM) sunitinib was able to partially reverse drug resistance mediated by P-gp and completely reverse resistance mediated by ABCG2. We further show a direct interaction of sunitinib with the substrate binding pocket of these transporters as it inhibited binding of the photoaffinity substrate [(125)I]iodoarylazidoprazosin to P-gp (IC(50) = 14.2 microM) and ABCG2 (IC(50) = 1.33 microM). Sunitinib stimulated the ATP hydrolysis by both transporters in a concentration-dependent manner. Conformation-sensitive antibody binding assays with the P-gp- and ABCG2-specific antibodies, UIC2 and 5D3, respectively, also confirmed the interaction of sunitinib with these transporters. Taken together, this is the first report showing that sunitinib inhibits transport mediated by ABC drug transporters, which may affect the bioavailability of drugs coadministered with sunitinib.
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PMID:Sunitinib (Sutent, SU11248), a small-molecule receptor tyrosine kinase inhibitor, blocks function of the ATP-binding cassette (ABC) transporters P-glycoprotein (ABCB1) and ABCG2. 1897 20

The present study aimed to elucidate the contribution of the intracellular binding of drugs to multidrug resistance. For this purpose, uptake of rhodamines was studied in cells whose mitochondria had been uncoupled with carbonyl cyanide m-chlorophenylhydrazone. Surprisingly, in a variety of drug-untreated cells, presumed to be sensitive to multidrug resistance-type drugs, rhodamines were excluded from entering the cells. Thus, the amount of rhodamine 123 taken up into parental untreated K562 cells was less than the amount bound to the cell exterior. Rhodamine uptake was prevented by an active efflux pump. The efflux was inhibited by 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) and MK571 and, to a lesser extent, by ATP depletion, indomethacin, probenecid and vanadate. All the inhibitors, apart from NBD-Cl, are known to modulate multidrug resistance-associated protein (MRP) 1. Because MRP1 was expressed in all the cell lines tested and the efflux of rhodamines in MRP1 over-expressing cells was abolished by NBD-Cl, it appears that rhodamines are excluded from these cells by MRP1. On the other hand, the uptake of rhodamines into cells respiring with their coupled mitochondria demonstrated diminished sensitivity to NBD-Cl and MK571. Thus, active pumping into the mitochondria allowed enhanced uptake into the cells, overcoming the innate resistance. The innate resistance provided by MRP1 to cells prevents rhodamine dyes, and possibly drugs such as doxorubicin, from achieving equilibration of their concentration in the cytoplasm with their concentration in the external medium. The protection provided to multidrug resistance cells by ABC transporters has to overcome competition by passive uptake of the drugs and binding/uptake of the drugs into intracellular targets.
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PMID:Competition between innate multidrug resistance and intracellular binding of rhodamine dyes. 1912 Apr 55

Sunitinib is an ATP-competitive multi-targeted tyrosine kinase inhibitor. In this study, we evaluated the possible interaction of sunitinib with P-glycoprotein (P-gp, ABCB1), multidrug resistance protein 1 (MRP1, ABCC1), breast cancer resistance protein (BCRP, ABCG2) and lung-resistance protein (LRP) in vitro. Our results showed that sunitinib completely reverse drug resistance mediated by ABCG2 at a non-toxic concentration of 2.5muM and has no significant reversal effect on ABCB1-, ABCC1- and LRP-mediated drug resistance, although a small synergetic effect was observed in combining sunitinib and conventional chemotherapeutic agents in ABCB1 overexpressing MCF-7/adr and parental sensitive MCF-7 cells, ABCC1 overexpressing C-A120 and parental sensitive KB-3-1 cells. Sunitinib significantly increased intracellular accumulation of rhodamine 123 and doxorubicin and remarkably inhibited the efflux of rhodamine 123 and methotrexate by ABCG2 in ABCG2-overexpressing cells, and also profoundly inhibited the transport of [(3)H]-methotrexate by ABCG2. However, sunitinib did not affect the expression of ABCG2 at mRNA or protein levels. In addition, sunitinib did not block the phosphorylation of Akt and Erk1/2 in ABCG2-overexpressing or parental sensitive cells. Overall, we conclude that sunitinib reverses ABCG2-mediated MDR through inhibiting the drug efflux function of ABCG2. These findings may be useful for cancer combinational therapy with sunitinib in the clinic.
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PMID:Sensitization of ABCG2-overexpressing cells to conventional chemotherapeutic agent by sunitinib was associated with inhibiting the function of ABCG2. 1923 21

Multidrug resistance-associated protein 1 (Mrp1; Abcc1) is expressed in sarcolemma of murine heart, where it probably protects the cardiomyocyte by mediating efflux of endo- and xenobiotics. We used doxorubicin (DOX), a chemotherapeutic drug known to induce oxidative stress and thereby cardiac injury, as a model cardiotoxic compound and observed changes in the Mrp1 expression pattern in cardiac tissue of DOX-versus saline-treated mice. Confocal immunofluorescent and immunogold electron microscopy, together with subcellular fractionation followed by immunoblot analyses and transport measurements, localized functional Mrp1 to mitochondria after DOX. Expressions of Mrp1 in heart homogenate, sarcolemma, and submitochondrial particles (SMP) were increased 1.6-, 2-, and 3-fold, respectively, at 24 h after DOX. Mitochondrial Mrp1 expression was markedly increased 72 h after DOX, whereas transport of Mrp1 substrates in SMP was maximal at 24 h. ATP-dependent transport in SMP occurred into an osmotically sensitive space and was inhibited by the anti-MRP1 antibody QCRL3. Adduction of a 190-kDa protein with the reactive lipid peroxidation product 4-hydroxy-2-nonenal (HNE) was detected in SMP and was maximal at 72 h after DOX; immunoprecipitation confirmed Mrp1-HNE adduction. In vitro, HNE (10 muM) inhibited mitochondrial respiration and transport activity in SMP, suggesting that Mrp1 is adversely affected by oxidative stress. These data demonstrate that after DOX, functional Mrp1 is detected in mitochondria in addition to that in sarcolemma; however, adduction with HNE inhibits Mrp1 activity. Mrp1 may serve to protect the heart by mediating the efflux of toxic products of oxidative stress from mitochondria and cardiomyocytes.
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PMID:Mrp1 localization and function in cardiac mitochondria after doxorubicin. 1923

Automated and manual annotation of the ATP binding cassette (ABC) superfamily in the Phytophthora ramorum and P. sojae genomes has identified 135 and 136 members, respectively, indicating that this family is comparable in size to the Arabidopsis thaliana and rice genomes, and significantly larger than that of two fungal pathogens, Fusarium graminearum and Magnaporthe grisea. The high level of synteny between these oomycete genomes extends to the ABC superfamily, where 108 orthologues were identified by phylogenetic analysis. The largest subfamilies include those most often associated with multidrug resistance. The P. ramorum genome contains 22 multidrug resistance-associated protein (MRP) genes and 49 pleiotropic drug resistance (PDR) genes, while P. sojae contains 20 MRP and 49 PDR genes. Tandem duplication events in the last common ancestor appear to account for much of the expansion of these subfamilies. Recent duplication events in the PDR and ABCG families in both the P. ramorum and the P. sojae genomes indicate that selective expansion of ABC transporters may still be occurring. In other kingdoms, subfamilies define both domain arrangements and proteins having a common phylogenetic origin, but this is not the case for several subfamilies in oomycetes. At least one ABCG type transporter is derived from a PDR transporter, while transporters in the ABCB-half family cluster with transporters from bacterial, plant, and metazoan genomes. Additional examples of transporters that appear to be derived from horizontal transfer events from bacterial genomes include components of transporters associated with iron uptake and DNA repair.
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PMID:Inventory and comparative evolution of the ABC superfamily in the genomes of Phytophthora ramorum and Phytophthora sojae. 1940 22

In vitro treatment of human T-cell leukemia cells with 7-hydroxymethotrexate, the major metabolite of methotrexate resulted in acquired resistance as a result of the complete loss of folypolyglutamate synthetase (FPGS) activity. This was in contradistinction to the major modality of antifolate resistance of impaired drug transport in leukemia cells exposed to methotrexate. To identify the genes associated with methotrexate and 7-hydroxymethotrexate resistance, we herein explored the patterns of genome-wide expression profiles in these antifolte-resistant leukemia sublines. mRNA levels of the reduced folate carrier, the primary influx transporter of folates and antifolates, were down-regulated more than two-fold in methotrexate-resistant cells. The dramatic loss of FPGS activity in 7-hydroxymethotrexate-resistant cells was associated with alterations in the expression of various genes aimed at preserving reduced folates and/or enhancing purine nucleotide biosynthesis, e.g. methylene tetrahydrofolate reductase, glycinamide ribonucleotide formyltransferase, adenosine deaminase, cystathionine beta synthase, as well as the ATP-dependent folate exporters BCRP/ABCG2 and MRP1/ABCC1. The observed changes in gene expression were generally not paralleled by acquired DNA copy numbers alterations, suggesting transcriptional regulatory mechanisms. Interestingly, gene expression of DNA/RNA metabolism and transport genes were more profoundly altered in methotrexate-resistant subline, whereas in 7-hydroxymethotrexate-resistant cells, the most profoundly affected groups of genes were those encoding for proteins involved in metabolism and cellular proliferation. Thus, the present investigation provides evidence that 7-hydroxymethotrexate induces gene expression alterations and an antifolate resistance modality that are distinct from its parent drug methotrexate.
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PMID:Gene expression profiling of leukemia T-cells resistant to methotrexate and 7-hydroxymethotrexate reveals alterations that preserve intracellular levels of folate and nucleotide biosynthesis. 1942 80

ABC transporter (ATP-binding-cassette transporter) proteins have been strongly associated with the phenomenon of multidrug resistance in cancer cells. Furthermore, their physiological expression has been studied in many organisms, including bacteria, fungi, plants and vertebrate or invertebrate animals. Their widespread expression through the evolution demonstrates their relevance to the survival of living things. In the present study, we characterized the functional activity of ABCB1 and ABCC1 proteins in gametes and embryonic cells of the sea urchin Echinometra lucunter. The ABC transporter proteins' functional activity was up-regulated post-fertilization. Eggs and spermatozoa of E. lucunter accumulated more C-AM (calcein acetoxymethyl ester), a fluorescent substrate of ABCB1 and ABCC1 proteins, than embryonic cells. Verapamil, reversin 205 and indomethacin were able to increase C-AM influx in eggs and embryos. However, verapamil and reversin 205 were more efficient than indomethacin, suggesting a predominance of ABCB1 protein over ABCC1 protein activity. Multidrug resistance modulating agents, at the concentration range that inhibited ABC transporter proteins, did not block the embryonic development until blastula stage. However, inhibition of ABCB1-mediated efflux by reversin 205 circumvented resistance of embryos to the antimitotic vinca alkaloid vinblastine. Embryonic development was more efficiently blocked when colchicine was previously added to eggs than to embryos 5 min after fertilization. This set of results suggests that these proteins act as a fundamental biochemical barrier conferring a protective physiological role against toxic xenobiotics in E. lucunter embryos.
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PMID:Characterization of functional activity of ABCB1 and ABCC1 proteins in eggs and embryonic cells of the sea urchin Echinometra lucunter. 1968 31

Cobalamin (Cbl, vitamin B(12)) deficiency in humans is a cause of hematologic and neurologic disorders. We show here that the cellular export of Cbl, in contrast to the carrier- and receptor-dependent cellular import of Cbl, occurs by transmembrane transport of "free" Cbl. Screening of candidate transporters by cellular gene silencing showed a role in cellular Cbl efflux of the ATP-binding cassette (ABC)-drug transporter, ABCC1, alias multidrug resistance protein 1 (MRP1), which is present in the basolateral membrane of intestinal epithelium and in other cells. The ability of MRP1 to mediate ATP-dependent Cbl transport was confirmed by vesicular transport experiments, and a physiologic role of MRP1 in mammalian Cbl homeostasis is indicated by the phenotype of knockout mice with targeted disruption of MRP1. These animals have a reduced concentration of Cbl in plasma and in the storage organs liver and kidney. In contrast, Cbl accumulates in the terminal part of the intestine of these mice, suggesting a functional malabsorption because of a lower epithelial basolateral Cbl efflux. The identification of this Cbl export mechanism now allows the delineation of a coherent pathway for Cbl trafficking from food to the body cells.
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PMID:Identification of multidrug resistance protein 1 (MRP1/ABCC1) as a molecular gate for cellular export of cobalamin. 2151 66

The activity of multidrug resistance (MDR) proteins in tumour cells is associated with an increased resistance to therapy and in consequence with a decreased effectiveness of chemotherapy. The majority of MDR molecules belong to a family of ABC (ATP binding cassette) transporters. Neuroblastoma (NBL) and rhabdomyosarcoma (RMS) are common solid tumours of childhood. The response to therapy is better in NBL, worse in RMS, but still unsatisfactory despite surgery and aggressive chemotherapy. The immunohistochemical staining for p-gp (p-glycoprotein), MRP1 (multidrug resistance associated protein 1), BCRP (breast cancer resistance protein) and LRP (lung resistance protein) expression was performed in primary tumour sections of NBL (10 cases) and RMS (10 cases). A different pattern of MDR expression in NBL and RMS were noted. In NBL, MRP1 was expressed in all studied tumours, p-gp, BCRP only in 3 out of 10 tumours, LRP, in 4 cases. The combination of more than one protein was noted in the majority of NBL tumours. In RMS, the expression of 3 or 4 MDR proteins was noted in 9 cases. The high expression of an MDR protein profile in RMS suggests various mechanisms acting simultaneously, which might explain chemotherapy resistance and a low percentage of long-time survival in this tumour.
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PMID:Expression of proteins associated with therapy resistance in rhabdomyosarcoma and neuroblastoma tumour cells. 2007 50


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