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

Multidrug resistance protein, also referred as P-glycoprotein (P-gp, MDR1; ABCB1) and multidrug resistance-associated protein (MRP) 1 (ABCC1) and 2 (ABCC2) are, thus far, candidates to cause antiepileptic drug (AED) resistance epilepsy. In this study, we investigated P-gp, MRP1 and MRP2 expression, localization and functional activity on cryosections and isolated human brain-derived microvascular endothelial cells (HBMEC) from epileptic patients (HBMEC-EPI) with hippocampal sclerosis (HS), as compared with HBMEC isolated from normal brain cortex (HBMEC-CTR). We examined the expression and distribution of three transporters, P-gp, MRP1 and MRP2 on two major parts of the resected tissue, the hippocampus and the parahippocampal gyrus (Gph). P-gp showed diffuse expression not only in endothelium but also by parenchymal cells in both the hippocampus and the Gph. MRP1 labeling was observed in parenchymal cells in the Gph. By contrast, MRP2 was mainly found in endothelium of the hippocampus. P-gp and MRP1 expression in the Gph was relatively high in the patient with long-term seizure history. Quantitative RT-PCR analysis of HBMEC revealed that MDR1, MRP1 as well as MRP5 (ABCC5) and MRP6 (ABCC6) were overexpressed in HBMEC-EPI at the mRNA level. HBMEC from both normal and epilepsy groups displayed protein expression of P-gp, whereas MRP1 and MRP2 were seen only in HBMEC-EPI. Accordingly, it is of particular interest that MRP functional activities were observed in HBMEC-EPI, but not in HBMEC-CTR. Our results suggest that complex MDR expression changes not only in the hippocampus but in the Gph may play a role in AED pharmacoresistance in intractable epilepsy patients with mesial temporal lobe epilepsy (MTLE) by altering the permeability of AEDs across the blood-brain barrier (BBB).
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PMID:Distribution and functional activity of P-glycoprotein and multidrug resistance-associated proteins in human brain microvascular endothelial cells in hippocampal sclerosis. 1636 Oct 82

Among the ABC proteins, some members including ABCB1, ABCC1, ABCC2 and ABCG2 are believed to contribute to multidrug resistance of cancer chemotherapy. In addition, the broad substrate-specificity and apical localization of the ABCB1 and ABCC2 in mucosal epithelium of intestine and hepatocyte give them a protective role against xenobiotics. The inter-individual variations in activity and expression levels of ABCB1 and ABCC2, thus, might affect on drug response and response to toxic substrates. In this review, I focus on (1) physiological and toxicological relevance of ABCB1 and ABCC2, and on (2) genetic variations of ABCB1 and ABCC2 genes and their association with biochemical function, expression level and tumor incidence.
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PMID:Single nucleotide polymorphisms in ABCC2 and ABCB1 genes and their clinical impact in physiology and drug response. 1637 77

P-glycoprotein (Pgp/ABCB1) and multidrug resistance related protein 1 (MRP1/ABCC1) were first described in multidrug resistant tumor cells. It is presently known that both proteins are also expressed in a variety of normal cells, including lymphocytes. ABCB1 activity has already been detected in subpopulations of murine thymocytes, but there was little information on the expression or activity of ABCC1 in these cells. The present work studied in mice the expression of both proteins by RT-PCR and immunofluorescence. It was possible to identify the presence of ABCB1 and to detect the expression of ABCC1 in these cells. The functional activities of these proteins were also studied in vivo and in vitro measuring the extrusion of fluorescent dyes in association with MDR modulators. Cyclosporine A, verapamil and trifluoperazine inhibited the activity of thymic ABCB1. Indomethacin, probenecid and MK571 were effective in inhibiting ABCC1 activity by thymic cells. ABCB1 was only active in a small percentage of thymocytes being present in the immature double negative (not CD4 nor CD8) subpopulation and the mature single positive (CD4 or CD8) subpopulations. The functional activity of ABCC1, on the other hand, was more homogeneously distributed being found in all thymocyte subpopulations. Possible physiological roles for these transporters on thymocytes are discussed.
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PMID:In vivo and in vitro modulation of MDR molecules in murine thymocytes. 1639 25

Based upon several previous reports, no consistent relationship between multidrug resistance protein 1 (MRP1, ABCC1) expression and cellular sensitivity to mitoxantrone (MX) toxicity can be ascertained; thus, the role of MRP1 in MX resistance remains controversial. The present study, using paired parental, MRP1-poor, and transduced MRP1-overexpressing MCF7 cells, unequivocally demonstrates that MRP1 confers resistance to MX cytotoxicity and that resistance is associated with reduced cellular accumulation of MX. This MRP1-associated reduced accumulation of MX was partially reversed by treatment of cells with 50 microM MK571 [3-[[3-[2-(7-chloroquinolin-2-yl)vinyl]phenyl]-(2-dimethylcarbamoylethylsulfanyl)methylsulfanyl] propionic acid]-an MRP inhibitor that increased MX accumulation in MRP1-expressing MCF7 cells but had no effect on MRP-poor MCF7 cells. Moreover, in vitro experiments using inside-out membrane vesicles show that MRP1 supports ATP-dependent, osmotically sensitive uptake of MX. Unlike ABCG2 (breast cancer resistance protein, mitoxantrone-resistant protein), MRP1-mediated MX transport is dependent upon the presence of glutathione or its S-methyl analog. In addition, MX stimulates transport of [3H]glutathione. Together, these data are consistent with the interpretation that MX efflux by MRP1 involves cotransport of MX and glutathione. The results suggest that MRP1-like the alternative MX transporters ABCG2 and ABCB1 (MDR1, P-glycoprotein)-can significantly influence tumor cell sensitivity to and pharmacological disposition of MX.
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PMID:Multidrug resistance protein 1 (MRP1, ABCC1) mediates resistance to mitoxantrone via glutathione-dependent drug efflux. 1643 18

With regard to structure-function relations of ATP-binding cassette (ABC) transporters several intriguing questions are in the spotlight of active research: Why do functional ABC transporters possess two ATP binding and hydrolysis domains together with two ABC signatures and to what extent are the individual nucleotide-binding domains independent or interacting? Where is the substrate-binding site and how is ATP hydrolysis functionally coupled to the transport process itself? Although much progress has been made in the elucidation of the three-dimensional structures of ABC transporters in the last years by several crystallographic studies including novel models for the nucleotide hydrolysis and translocation catalysis, site-directed mutagenesis as well as the identification of natural mutations is still a major tool to evaluate effects of individual amino acids on the overall function of ABC transporters. Apart from alterations in characteristic sequence such as Walker A, Walker B and the ABC signature other parts of ABC proteins were subject to detailed mutagenesis studies including the substrate-binding site or the regulatory domain of CFTR. In this review, we will give a detailed overview of the mutation analysis reported for selected ABC transporters of the ABCB and ABCC subfamilies, namely HsCFTR/ABCC7, HsSUR/ABCC8,9, HsMRP1/ABCC1, HsMRP2/ABCC2, ScYCF1 and P-glycoprotein (Pgp)/MDR1/ABCB1 and their effects on the function of each protein.
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PMID:Insight in eukaryotic ABC transporter function by mutation analysis. 1644 1

Current clinicopathological staging systems have the advantage of standardized criteria for assessing tumour stage, and a relationship between advancing tumour stage and poor prognosis has been established for most cancers. However, these tools have not led to clear criteria for therapy selection in individual patients. Indeed, the concept of therapy based on anatomical location seems quaint. Therefore, a representative drug pathway (irinotecan) was evaluated across common tumour types to test the hypothesis that pharmacological proteins are expressed independent of anatomical location. Many enzymes are involved in controlling the disposition of irinotecan, including the cellular target (TOP1), metabolism enzymes (CES2, UGT1A1, CYP3A4, CYP3A5), and cellular transporters of the anti-cancer agent (ABCB1, ABCC1, ABCC2, ABCC3, ABCC5, ABCG2). These 11 proteins were evaluated in tissue microarrays containing colon, breast, prostate, ovary, and lung cancers; brain tumours; melanoma; lymphoma; and selected normal tissues. A total of 255 tumours and 37 normal tissue samples were evaluable for all proteins. Linear discriminant analysis designed to predict the tissue type from the protein expression levels revealed a 49.6% misclassification rate, indicating that protein expression of this drug pathway is not associated with tissue type. Cluster analysis identified a variety of tumours with the same pharmacological profile. The anatomy independence of drug pathways stimulates efforts to move away from our traditional approaches to the selection of cancer therapy.
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PMID:Expression of drug pathway proteins is independent of tumour type. 1650 19

Breast cancer resistance protein (BCRP/ABCG2) belongs to the ATP-binding cassette (ABC) transporter superfamily. It is able to efflux a broad range of anti-cancer drugs through the cellular membrane, thus limiting their anti-proliferative effects. Due to its relatively recent discovery in 1998, and in contrast to the other ABC transporters P-glycoprotein (MDR1/ABCB1) and multidrug resistance-associated protein (MRP1/ABCC1), only a few BCRP inhibitors have been reported. This review summarizes the known classes of inhibitors that are either specific for BCRP or also inhibit the other multidrug resistance ABC transporters. Information is presented on structure-activity relationship aspects and how modulators may interact with BCRP.
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PMID:Inhibitors of cancer cell multidrug resistance mediated by breast cancer resistance protein (BCRP/ABCG2). 1652 Jun 51

The increased expression of drug transporters following cancer chemotherapy contributes to resistance. This may reflect transcriptional up-regulation and/or clonal selection. We quantified the expression of mRNA for ABCB1 (mdr1), ABCC1 (mrp1), ABCC2 (mrp2) and ABCC3 (mrp3) to evaluate the potential contribution of induction. ABCB1, ABCC1-3 mRNAs were quantified by real time RT-PCR and normalized to GAPDH. We used intestinal cells that express high pregnane X receptor (LS174T), low pregnane X receptor (Caco-2) and lung cells (A549) that express glucocorticoid receptor and low pregnane X receptor. Rifampin (10 microM) caused significant induction of ABCB1 (595+/-263%, p<0.05) in LS174T cells but induction was absent in Caco-2 or A549 cells. ABCC1 was not induced in any cell at 24, 48 and 72 h following rifampin treatment. In contrast, vincristine (10 nM and 100 nM), a ligand for ABCB1 and ABCC1-3 and a potential PXR/CAR ligand, induced ABCC2 and ABCC3 expression in LS174T cells at 48 h (372+/-87% and 303+/-42%, respectively, p<0.05). A similar induction of ABCC2 and ABCC3 genes was also seen with 10 nM VCR in A549 cells following 48 h treatment. In summary, there may be a significant contribution of transcriptional activation to multi-drug resistance. However, this is cell selective and is not necessarily dependent on PXR mediated effects.
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PMID:Vincristine transcriptional regulation of efflux drug transporters in carcinoma cell lines. 1662 Jul 87

Dendritic cells (DC) express the ATP-binding cassette (ABC) transporters P-glycoprotein (ABCB1) and multidrug resistance protein 1 (MRP1; ABCC1). Functionally, both these transporters have been described to be required for efficient DC and T cell migration. In this study, we report that MRP1 activity is also crucial for differentiation of DC. Inhibition of MRP1, but not P-glycoprotein, transporter activity with specific antagonists during in vitro DC differentiation interfered with early DC development. Impaired interstitial and Langerhans DC differentiation was characterized by 1) morphological changes, reflected by dropped side scatter levels in flow cytometric analysis and 2) phenotypic changes illustrated by maintained expression of the monocytic marker CD14, lower expression levels of CD40, CD86, HLA-DR, and a significant decrease in the amount of cells expressing CD1a, CD1c, and Langerin. Defective DC differentiation also resulted in their reduced ability to stimulate allogeneic T cells. We identified the endogenous CD1 ligands sulfatide and monosialoganglioside GM1 as MRP1 substrates, but exogenous addition of these substrates could not restore the defects caused by blocking MRP1 activity during DC differentiation. Although leukotriene C(4) was reported to restore migration of murine Mrp1-deficient DC, the effects of MRP1 inhibition on DC differentiation appeared to be independent of the leukotriene pathway. Though MRP1 transporter activity is important for DC differentiation, the relevant MRP1 substrate, which is required for DC differentiation, remains to be identified. Altogether, MRP1 seems to fulfill an important physiological role in DC development and DC functions.
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PMID:Dendritic cells require multidrug resistance protein 1 (ABCC1) transporter activity for differentiation. 1662 83

Drug resistance is a major obstacle to the successful chemotherapy. Several ATP-binding cassette (ABC) transporters including ABCB1, ABCC1 and ABCG2 have been known to be important mediators of chemoresistance. Using oligonucleotide microarrays (HG-U133 Plus 2.0; Affymetrix), we analyzed the ABC transporter gene expression profiles in breast cancer patients who underwent sequential weekly paclitaxel/FEC (5-fluorouracil, epirubicin and cyclophosphamide) neoadjuvant chemotherapy. We compared the ABC transporter expression profile between two classes of pretreatment tumor samples divided by the patients' pathological response to neoadjuvant chemotherapy (residual disease [RD] versus pathologic complete response [pCR]) ABCB3, ABCC7 and ABCF2 showed significantly high expression in the pCR. Several ABC transporters including ABCC5, ABCA12, ABCA1 ABCC13, ABCB6 and ABCC11 showed significantly increased expression in the RD (p<0.05). We evaluated the feasibility of developing a multigene predictor model of pathologic response to neoadjuvant chemotherapy using gene expression profiles of ABC transporters. The prediction error was evaluated by leave-one-out cross-validation (LOOCV). A multigene predictor model with the ABC transporters differentially expressed between the two classes (p<or=0.003) showed an average 92.8% of predictive accuracy (95% CI, 88.0-97.4%) with a 93.2% (95% CI, 85.2-100%) positive predictive value for pCR, a 93.6% (95% CI, 87.8-99.4%) negative predictive value, a sensitivity of 88.1%(95% CI, 76.8-99.4%), and a specificity of 95.9% (91.1% CI, 87.8-100%). Our results suggest that several ABC transporters in human breast cancer cells may affect the clinical response to neoadjuvant chemotherapy, and transcriptional profiling of these genes may be useful to predict the pathologic response to sequential weekly paclitaxel/FEC in breast cancer patients.
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PMID:Gene expression profiling of ATP-binding cassette (ABC) transporters as a predictor of the pathologic response to neoadjuvant chemotherapy in breast cancer patients. 1675 23


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