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Johann W Bauer - One of the best experts on this subject based on the ideXlab platform.
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the design and optimization of rna trans splicing molecules for skin cancer therapy
Molecular Oncology, 2013Co-Authors: Christina Gruber, Eva M Murauer, Ulrich Koller, S. Hainzl, Thomas Kocher, Clemens Hüttner, Andrew P. South, Helmut Hintner, Johann W BauerAbstract:Targeting tumor marker genes by RNA trans-splicing is a promising means to induce tumor cell-specific death. Using a screening system we designed RNA trans-splicing molecules (RTM) specifically binding the pre-mRNA of SLCO1B3, a marker gene in epidermolysis bullosa associated squamous cell carcinoma (EB-SCC). Specific trans-splicing, results in the fusion of the endogenous target mRNA of SLCO1B3 and the coding sequence of the suicide gene, provided by the RTM. SLCO1B3-specific RTMs containing HSV-tk were analyzed regarding their trans-splicing potential in a heterologous context using a SLCO1B3 expressing minigene (SLCO1B3-MG). Expression of the chimeric SLCO1B3-tk was detected by semi-quantitative RT-PCR and Western blot analysis. Cell viability and apoptosis assays confirmed that the RTMs induced suicide gene-mediated apoptosis in SLCO1B3-MG expressing cells. The lead RTM also showed its potential to facilitate a trans-splicing reaction into the endogenous SLCO1B3 pre-mRNA in EB-SCC cells resulting in tk-mediated apoptosis. We assume that the pre-selection of RTMs by our inducible cell-death system accelerates the design of optimal RTMs capable to induce tumor specific cell death in skin cancer cells.
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The design and optimization of RNA trans‐splicing molecules for skin cancer therapy
Molecular oncology, 2013Co-Authors: Christina Gruber, Eva M Murauer, Ulrich Koller, S. Hainzl, Thomas Kocher, Clemens Hüttner, Andrew P. South, Helmut Hintner, Johann W BauerAbstract:Targeting tumor marker genes by RNA trans-splicing is a promising means to induce tumor cell-specific death. Using a screening system we designed RNA trans-splicing molecules (RTM) specifically binding the pre-mRNA of SLCO1B3, a marker gene in epidermolysis bullosa associated squamous cell carcinoma (EB-SCC). Specific trans-splicing, results in the fusion of the endogenous target mRNA of SLCO1B3 and the coding sequence of the suicide gene, provided by the RTM. SLCO1B3-specific RTMs containing HSV-tk were analyzed regarding their trans-splicing potential in a heterologous context using a SLCO1B3 expressing minigene (SLCO1B3-MG). Expression of the chimeric SLCO1B3-tk was detected by semi-quantitative RT-PCR and Western blot analysis. Cell viability and apoptosis assays confirmed that the RTMs induced suicide gene-mediated apoptosis in SLCO1B3-MG expressing cells. The lead RTM also showed its potential to facilitate a trans-splicing reaction into the endogenous SLCO1B3 pre-mRNA in EB-SCC cells resulting in tk-mediated apoptosis. We assume that the pre-selection of RTMs by our inducible cell-death system accelerates the design of optimal RTMs capable to induce tumor specific cell death in skin cancer cells.
Mikko Niemi - One of the best experts on this subject based on the ideXlab platform.
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Genetics is a major determinant of expression of the human hepatic uptake transporter OATP1B1, but not of OATP1B3 and OATP2B1
Genome Medicine, 2013Co-Authors: Anne T Nies, Mikko Niemi, Oliver Burk, Stefan Winter, Ulrich M Zanger, Bruno Stieger, Matthias Schwab, Elke SchaeffelerAbstract:Background Organic anion transporting polypeptide (OATP) 1B1, OATP1B3, and OATP2B1 (encoded by SLCO1B1, SLCO1B3, SLCO2B1 ) mediate the hepatic uptake of endogenous compounds like bile acids and of drugs, for example, the lipid-lowering atorvastatin, thereby influencing hepatobiliary elimination. Here we systematically elucidated the contribution of SLCO variants on expression of the three hepatic OATPs under consideration of additional important covariates. Methods Expression was quantified by RT-PCR and immunoblotting in 143 Caucasian liver samples. A total of 109 rare and common variants in the SLCO1B3-SLCO1B1 genomic region and the SLCO2B1 gene were genotyped by MALDI-TOF mass spectrometry and genome-wide SNP microarray technology. SLCO1B1 haplotypes affecting hepatic OATP1B1 expression were associated with pharmacokinetic data of the OATP1B1 substrate atorvastatin ( n = 82). Results Expression of OATP1B1, OATP1B3, and OATP2B1 at the mRNA and protein levels showed marked interindividual variability. All three OATPs were expressed in a coordinated fashion. By a multivariate regression analysis adjusted for non-genetic and transcription covariates, increased OATP1B1 expression was associated with the coding SLCO1B1 variant c.388A > G (rs2306283) even after correction for multiple testing ( P = 0.00034). This held true for haplotypes harboring c.388A > G but not the functional variant c.521T > C (rs4149056) associated with statin-related myopathy. c.388A > G also significantly affected atorvastatin pharmacokinetics. SLCO variants and non-genetic and regulatory covariates together accounted for 59% of variability of OATP1B1 expression. Conclusions Our results show that expression of OATP1B1, but not of OATP1B3 and OATP2B1, is significantly affected by genetic variants. The SLCO1B1 variant c.388A > G is the major determinant with additional consequences on atorvastatin plasma levels.
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No significant effect of the SLCO1B1 polymorphism on the pharmacokinetics of ursodeoxycholic acid
European Journal of Clinical Pharmacology, 2011Co-Authors: Xiaoqiang Xiang, Juha Vakkilainen, Janne T. Backman, Pertti J. Neuvonen, Mikko NiemiAbstract:Purpose To investigate possible effects of the SLCO1B1 polymorphism on the pharmacokinetics of ursodeoxycholic acid (UDCA) and its metabolites in healthy volunteers. Methods In a crossover study with two phases, 15 healthy volunteers with the SLCO1B1 * 1A /* 1A genotype, seven with the * 1B /* 1B genotype, and five with the * 15 /* 15 or * 5 /* 15 genotype ingested placebo or a single 150-mg dose of UDCA. Plasma concentrations of bile acids and their biosynthesis marker were determined up to 24 h post-ingestion by liquid chromatography–tandem mass spectrometry. Results The SLCO1B1 genotype had no significant effect on the pharmacokinetics of UDCA. The geometric mean ratios (95% confidence interval) of UDCA area under the plasma concentration-time curve from 0 to 12 h (AUC_0-12) in subjects with the SLCO1B1 * 1B /* 1B genotype and in subjects with the SLCO1B1 * 15 /* 15 or * 5 /* 15 genotype to the AUC_0-12 in subjects with the SLCO1B1 * 1A /* 1A genotype were 1.07 (0.85, 1.35; P = 0.459) and 0.93 (0.75, 1.15; P = 0.563), respectively. In addition, following either placebo or UDCA administration, the SLCO1B1 polymorphism showed no association with the AUC_0-24 of the glycine and taurine conjugates of UDCA, with endogenous bile acids, or with the incremental AUC_0-24 of a bile acid synthesis marker. Compared with placebo, UDCA ingestion increased the AUC_0-24 of cholic acid, glycochenodeoxycholic acid, glycocholic acid, and glycodeoxycholic acid by 1.5-, 1.1-, 1.2-, and 1.2- fold ( P
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Frequencies of single-nucleotide polymorphisms of SLCO1A2, SLCO1B3 and SLCO2B1 genes in a Finnish population.
Basic & clinical pharmacology & toxicology, 2010Co-Authors: Alli Laitinen, Mikko NiemiAbstract:Abstract: Organic anion transporting polypeptides 1A2, 1B3 and 2B1 (OATP1A2, OATP1B3 and OATP2B1) are expressed in tissues important for pharmacokinetics, and mediate the cellular influx of various endogenous and exogenous compounds, including drugs. The aim of the study was to investigate the frequencies of single-nucleotide polymorphisms (SNP) of SLCO1A2, SLCO1B3 and SLCO2B1 in a Finnish population. The distribution of nine non-synonymous SLCO1A2, SLCO1B3 and SLCO2B1 SNPs was determined in 552 healthy Finnish Caucasian participants by using allelic discrimination with TaqMan 5′nuclease assays. The SLCO1A2 c.38T>C (p.Ile13Thr) and c.516C>T (p.Glu172Asp) SNPs were found with variant allele frequencies of 12.9% (95% confidence interval: 11.0–15.0) and 7.2% (5.8–8.8). The variant allele frequencies of SLCO1B3 c.334T>G (p.Ser112Ala), c.699G>A (p.Met233Ile) and c.767G>C (p.Gly256Ala) were 77.0% (74.4–79.4), 76.9% (74.3–79.3) and 12.8% (10.9–14.9), respectively. None of the participants carried the SLCO1B3 c.1309G>A (p.Gly437Ser) SNP. The SLCO2B1 c.601G>A (p.Val201Met), c.935G>A (p.Arg312Gln) and c.1457C>T (p.Ser486Phe) variant allele frequencies were 2.1% (1.4–3.1), 13.6% (11.7–15.7) and 2.8% (2.0–4.0), respectively. The SLCO1B3 c.334T>G and c.699G>A SNPs were in a nearly complete linkage disequilibrium (r² = 0.99, D′ = 1.00), all other SNP pairs showed only a weak correlation. In conclusion, non-synonymous sequence variations of SLCO1A2, SLCO1B3 and SLCO2B1 occur at high frequencies in the Finnish population.
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SLCO1B1 polymorphism and oral antidiabetic drugs.
Basic & clinical pharmacology & toxicology, 2010Co-Authors: Annikka Kalliokoski, Pertti J. Neuvonen, Mikko NiemiAbstract:Abstract: Organic anion-transporting polypeptide 1B1 (OATP1B1; gene: SLCO1B1) is an influx transporter expressed on the sinusoidal membrane of human hepatocytes, where it mediates the uptake of its substrates from blood into liver. In vitro, the SLCO1B1 c.521T > C (p.Val174Ala) single-nucleotide polymorphism (SNP) has been associated with reduced and the c.388A > G (p.Asn130Asp) SNP with both enhanced and reduced transport activity of OATP1B1. In vivo in humans, the c.521C allele (present in SLCO1B1*5 and *15 haplotypes) is associated with decreased hepatic uptake and increased plasma concentrations of several OATP1B1 substrates. The SLCO1B1*1B (c.388G-c.521T) haplotype is associated with enhanced hepatic uptake and decreased plasma concentrations of some OATP1B1 substrates. The SLCO1B1 c.521CC genotype has been associated with an about 60-190% increased, and the SLCO1B1*1B/*1B genotype with an about 30% decreased area under the plasma concentration-time curve of repaglinide. Moreover, SLCO1B1 polymorphism can affect the extent of interaction between OATP1B1 inhibitors and repaglinide. Accordingly, SLCO1B1 genotyping may help in choosing the optimal starting dose of repaglinide. In Chinese individuals, the SLCO1B1 c.521C allele has been associated with increased plasma concentrations of nateglinide, but the association could not be replicated in Caucasians. SLCO1B1 genotype has had no effect on the pharmacokinetics of rosiglitazone, pioglitazone or their metabolites. The hepatic uptake of metformin is mediated by organic cation transporters 1 and 3, and the liver is not important for the elimination or action of the dipeptidylpeptidase 4 inhibitors sitagliptin, vildagliptin and saxagliptin. Therefore, SLCO1B1 polymorphism unlikely affects the response to these antidiabetics. Possible effects of SLCO1B1 polymorphism on sulfonylureas remain to be investigated.
Ron H.j. Mathijssen - One of the best experts on this subject based on the ideXlab platform.
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The influence of single-nucleotide polymorphisms on overall survival and toxicity in cabazitaxel-treated patients with metastatic castration-resistant prostate cancer
Cancer Chemotherapy and Pharmacology, 2020Co-Authors: Bodine P. S. Belderbos, Samira El Bouazzaoui, Ron H.j. Mathijssen, Mirjam With, Rajbir K. Singh, Bram C. Agema, Esther Oomen-de Hoop, Ronald Wit, Ron H. N. Schaik, Sander BinsAbstract:Purpose Cabazitaxel, used in patients with metastatic castration-resistant prostate cancer (mCRPC), is associated with adverse events which may require dose reductions or discontinuation of treatment. We investigated the potential association of single-nucleotide polymorphisms (SNPs) in genes encoding drug transporters and drug-metabolizing enzymes with cabazitaxel toxicity, overall survival (OS) and pharmacokinetics (PK). Methods A total of 128 cabazitaxel-treated mCRPC patients, of whom prospectively collected data on toxicity and OS were available and 24 mCRPC patients with available cabazitaxel PK measurements, were genotyped using genomic DNA obtained from EDTA blood. The SLCO1B1 (388A > G; *1B; rs2306283 and 521 T > C; *5; rs4149056 and haplotype SLCO1B1*15 ) , SLCO1B3 (334 T > G; rs4149117) , CYP3A4 ( *22 ; rs35599367) , CYP3A5 (*3; rs776746) , ABCB1 (3435C > T; rs1045642), and TUBB1 (57 + 87A > C; rs463312) SNPs were tested for their association with clinical and PK parameters by univariate/multivariate logistic regression, log-rank test, or Kruskal–Wallis test. Results The SLCO1B1*15 haplotype was significantly associated with a lower incidence of leukopenia and neutropenia ( p = 0.020 and p = 0.028, respectively). Patients harboring a homozygous variant for SLCO1B1*1B experienced higher rate ≥ grade 3 ( p = 0.042). None of the SNPs were associated with pharmacokinetics or OS. Conclusions In this study, SLCO1B1 ( SLCO1B1*15 and SLCO1B1*1B ) was associated with cabazitaxel-induced adverse events in mCRPC patients. As the associations were opposite to previous studies in other drugs and contradicted an underlying pharmacokinetic rationale, these findings are likely to be false-positive and would ideally be validated with even larger (pharmacokinetic) cohorts.
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Loss of SLCO1B3 drives taxane resistance in prostate cancer
British Journal of Cancer, 2016Co-Authors: Ellen S. De Morree, Ron H.j. Mathijssen, Ashraf Aghai, Alice A. Gibson, E.a.c. Wiemer, René Böttcher, Herman Burger, Robert J Van Soest, Corrina M De Ridder, Alex SparreboomAbstract:Background: Both taxanes, docetaxel and cabazitaxel, are effective treatments for metastatic castration-resistant prostate cancer (mCRPC). However, resistance to taxanes is common. Our objective was to investigate mechanisms of taxane resistance in prostate cancer. Methods: Two docetaxel-resistant patient-derived xenografts (PDXs) of CRPC were established (PC339-DOC and PC346C-DOC) in male athymic nude mice by frequent intraperitoneal administrations of docetaxel. Next-generation sequencing was performed on PDX tissue pre- and post-docetaxel resistance and gene expression profiles were compared. [^14C]-docetaxel and [^14C]-cabazitaxel uptake assays in vitro and cytotoxicity assays were performed to validate direct involvement of transporter genes in taxane sensitivity. Results: Organic anion-transporting polypeptide (SLCO1B3), an influx transporter of docetaxel, was significantly downregulated in PC346C-DOC tumours. In accordance with this finding, intratumoural concentrations of docetaxel and cabazitaxel were significantly decreased in PC346C-DOC as compared with levels in chemotherapy-naive PC346C tumours. In addition, silencing of SLCO1B3 in chemo-naive PC346C resulted in a two-fold decrease in intracellular concentrations of both taxanes. Overexpression of SLCO1B3 showed higher sensitivity to docetaxel and cabazitaxel. Conclusions: The SLCO1B3 determines intracellular concentrations of docetaxel and cabazitaxel and consequently influences taxane efficacy. Loss of the drug transporter SLCO1B3 may drive taxane resistance in prostate cancer.
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Loss of SLCO1B3 drives taxane resistance in prostate cancer
British journal of cancer, 2016Co-Authors: Ellen S. De Morree, Ron H.j. Mathijssen, Ashraf Aghai, Alice A. Gibson, E.a.c. Wiemer, René Böttcher, Robert J. Van Soest, Corrina M.a. De Ridder, Herman Burger, Alex SparreboomAbstract:Both taxanes, docetaxel and cabazitaxel, are effective treatments for metastatic castration-resistant prostate cancer (mCRPC). However, resistance to taxanes is common. Our objective was to investigate mechanisms of taxane resistance in prostate cancer. Two docetaxel-resistant patient-derived xenografts (PDXs) of CRPC were established (PC339-DOC and PC346C-DOC) in male athymic nude mice by frequent intraperitoneal administrations of docetaxel. Next-generation sequencing was performed on PDX tissue pre- and post-docetaxel resistance and gene expression profiles were compared. [14C]-docetaxel and [14C]-cabazitaxel uptake assays in vitro and cytotoxicity assays were performed to validate direct involvement of transporter genes in taxane sensitivity. Organic anion-transporting polypeptide (SLCO1B3), an influx transporter of docetaxel, was significantly downregulated in PC346C-DOC tumours. In accordance with this finding, intratumoural concentrations of docetaxel and cabazitaxel were significantly decreased in PC346C-DOC as compared with levels in chemotherapy-naive PC346C tumours. In addition, silencing of SLCO1B3 in chemo-naive PC346C resulted in a two-fold decrease in intracellular concentrations of both taxanes. Overexpression of SLCO1B3 showed higher sensitivity to docetaxel and cabazitaxel. The SLCO1B3 determines intracellular concentrations of docetaxel and cabazitaxel and consequently influences taxane efficacy. Loss of the drug transporter SLCO1B3 may drive taxane resistance in prostate cancer.
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Polymorphisms in SLCO1B1 and UGT1A1 are associated with sorafenib-induced toxicity
Pharmacogenomics, 2016Co-Authors: Sander Bins, Anne Lenting, Samira El Bouazzaoui, Leni Van Doorn, Esther Oomen-de Hoop, Ferry A.l.m. Eskens, Ron H.n. Van Schaik, Ron H.j. MathijssenAbstract:Aim: Sorafenib-treated patients display a substantial variation in the incidence of toxicity. We aimed to investigate the association of genetic polymorphisms with observed toxicity on sorafenib. Patients & methods: We genotyped 114 patients that were treated with sorafenib at the Erasmus MC Cancer Institute, the Netherlands, for SLCO1B1, SLCO1B3, ABCC2, ABCG2, UGT1A1 and UGT1A9. Results: The UGT1A1 (rs8175347) polymorphism was associated with hyperbilirubinemia and treatment interruption. Polymorphisms in SLCO1B1 (rs2306283, rs4149056) were associated with diarrhea and thrombocytopenia, respectively. None of the investigated polymorphisms was associated with overall or progression-free survival in hepatocellular cancer patients. Conclusion: Polymorphisms in SLCO1B1 and UGT1A1 are associated with several different sorafenib side effects.
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Abstract 255: Docetaxel inhibits testosterone mediated activation of the AR pathway by SLCO1B3
Experimental and Molecular Therapeutics, 2016Co-Authors: Ellen S. De Morree, Ron H.j. Mathijssen, Alex Sparreboom, Ashraf Aghai, Alice A. Gibson, E.a.c. Wiemer, Wytske M. Van Weerden, Ronald WitAbstract:Background Docetaxel is the first line of chemotherapy in metastatic castration resistant prostate cancer (mCRPC) patients. More than 50% of prostate cancer tumors express the solute carrier organic anion transporter family member 1B3 (SLCO1B3/OATP1B3), an uptake transporter that actively transports docetaxel into the cell. Interestingly, SLCO1B3 is also a transporter of endogenous substrates, such as testosterone. As the androgen receptor (AR) pathway is still active in mCRPC patients, we hypothesize that docetaxel can interact with the uptake of testosterone through SLCO1B3, which would result in decreased AR-pathway activation and subsequent tumor growth inhibition. Materials and Methods SLCO1B3 overexpressing cells (CHO-1B3) were used for uptake experiments with radioactively labeled hormones, such as estradiol-β-glucuronide (E2G). We stably transfected prostate cancers cells (PC346C-DCC and PC346C-DCC-G) with SLCO1B3 or with a green fluorescent protein (GFP) tag only. An androgen responsive element (ARE)-luciferase assay was created as a sensitive measure of AR pathway activation. ARE-activity and prostate specific antigen (PSA) production were analyzed with an ELISA assay after exposure to 1nM testosterone for 30 minutes with or without preincubation with docetaxel 10 μM in SLCO1B3 overexpressing and GFP- tagged control cells. Results SLCO1B3 overexpressing cells showed testosterone-mediated activation of the AR pathway: ARE-activity increased 6.4-fold and PSA production 7-fold in SLCO1B3-overexpressing cells as compared to control cells. Pre-incubation of CHO-1B3 cells with docetaxel resulted in reduced uptake of E2G to the level observed in control cells. Similarly, after exposure to testosterone and docetaxel ARE-activity was significantly decreased in SLCO1B3-overexpressing cells compared to that of controls. Conclusion: Docetaxel inhibits the activation of the AR pathway via SLCO1B3. This is a novel anti-androgenic effect exerted by docetaxel in addition to inhibition of the AR translocation that we demonstrated previously. Experiments are ongoing to investigate if testosterone uptake via SLCO1B3 is inhibited by docetaxel. Citation Format: Ellen S. de Morree, Ashraf Aghai, Alice A. Gibson, Ron H.J. Mathijssen, Eric A.C. Wiemer, Alex Sparreboom, Wytske M. van Weerden, Ronald de Wit. Docetaxel inhibits testosterone mediated activation of the AR pathway by SLCO1B3. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 255.
Tristan M. Sissung - One of the best experts on this subject based on the ideXlab platform.
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Abstract A069: Mechanisms governing the transcriptional regulation of the liver-specific transporter OATP1B3 in prostate cancer
Cellular Responses to Therapy, 2019Co-Authors: Roberto H. Barbier, Tristan M. Sissung, Jonathan D. Strope, Edel M. Mccrea, Douglas K. Price, Cindy H. Chau, Phoebe A. Huang, William D. FiggAbstract:Background: The testosterone uptake transporter OATP1B3 is expressed de novo in prostate tumors and SLCO1B3 gene (encoding OATP1B3) variants are associated with clinical outcomes in patients with prostate cancer receiving androgen deprivation therapy (ADT) and in castration-resistant disease. These findings support the role of OATP1B3 as a major physiologic contributor to androgen distribution and a contributor to resistance to ADT. We have previously shown CBP/p300-mediated SLCO1B3 expression; however, specific transcriptional regulation of de novo expression remains to be elucidated. We characterized the SLCO1B3 promoter in order to better understand the regulatory mechanisms that govern its expression in prostate cancer. Methods: Functional analysis of the SLCO1B3 promoter was conducted using 5’ deletion mutagenesis. Transcriptional activity of the SLCO1B3 gene was measured using the SLCO1B3 promoter-luciferase reporter plasmids, transient transfections and luciferase reporter assays. Promoter activity was modulated by co-transfection with the p300 expression plasmid or treatment with various p300 inhibitor compounds (chetomin, HATi II, or C646). Results: We detected different transcriptional profiles across multiple prostate cancer cells (22Rv1, LNCaP, PC3) and identified a conserved domain responsible for SLCO1B3 transcriptional activity. Variable transcriptional changes in response to p300 inhibitor treatments were observed in both the conserved domain plasmid and the full-length reporter with the HATi II compound showing a consistent 2 to 3-fold increase in luciferase activity. Putative transcription factor binding sites are being evaluated by site-directed mutagenesis to determine potential regulatory elements involved in transcriptional activity of the gene. Conclusions: Our data suggest that several multi-protein transcription factor complexes assemble at distinct regulatory elements in the SLCO1B3 promoter, driving tissue-specific expression of OATP1B3 in prostate cancer. Understanding the underlying regulatory mechanisms of OATP1B3 expression and the transporter’s role in prostate cancer progression will aid in its development as a potential therapeutic target. Citation Format: Roberto H Barbier, Edel M McCrea, Jonathan D Strope, Phoebe A Huang, Tristan M Sissung, Douglas K Price, Cindy H Chau, William D Figg. Mechanisms governing the transcriptional regulation of the liver-specific transporter OATP1B3 in prostate cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A069. doi:10.1158/1535-7163.TARG-19-A069
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Differential Expression of OATP1B3 Mediates Unconjugated Testosterone Influx
Molecular cancer research : MCR, 2017Co-Authors: Tristan M. Sissung, Ariel M. Ley, Jonathan D. Strope, Edel M. Mccrea, Shaunna L. Beedie, Cody J. Peer, Suneet Shukla, Jennifer Van Velkinburgh, Kelie M. Reece, Sarah M. TroutmanAbstract:Castration-resistant prostate cancer (CRPC) has greater intratumoral testosterone concentrations than similar tumors from eugonadal men; simple diffusion does not account for this observation. This study was undertaken to ascertain the androgen uptake kinetics, functional, and clinical relevance of de novo expression of the steroid hormone transporter OATP1B3 ( SLCO1B3 ). Experiments testing the cellular uptake of androgens suggest that testosterone is an excellent substrate of OATP1B3 ( K m = 23.2 μmol/L; V max = 321.6 pmol/mg/minute), and cells expressing a doxycycline-inducible SLCO1B3 construct had greater uptake of a clinically relevant concentration of 3H-testosterone (50 nmol/L; 1.6-fold, P = 0.0027). When compared with Slco1b2 (−/−) mice, Slco1b2 (−/−)/ hSLCO1B3 knockins had greater hepatic uptake (15% greater AUC, P = 0.0040) and lower plasma exposure to 3H-testosterone (17% lower AUC, P = 0.0030). Of 82 transporters genes, SLCO1B3 is the second-most differentially expressed transporter in CRPC cell lines (116-fold vs. androgen-sensitive cells), with a differentially spliced cancer-type ct- SLCO1B3 making up the majority of SLCO1B3 expression. Overexpression of SLCO1B3 in androgen-responsive cells results in 1.5- to 2-fold greater testosterone uptake, whereas siRNA knockdown of SLCO1B3 in CRPC cells did not change intracellular testosterone concentration. Primary human prostate tumors express SLCO1B3 to a greater extent than ct-SLCO1B3 (26% of total SLCO1B3 expression vs. 0.08%), suggesting that androgen uptake in these tumor cells also is greater. Non-liver tumors do not differentially express SLCO1B3. Implications: This study suggests that de novo OATP1B3 expression in prostate cancer drives greater androgen uptake and is consistent with previous observations that greater OATP1B3 activity results in the development of androgen deprivation therapy resistance and shorter overall survival. Mol Cancer Res; 15(8); 1096–105. ©2017 AACR .
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SLCO Transport Genes in Prostate Cancer—Letter
Cancer Epidemiology Biomarkers & Prevention, 2011Co-Authors: Tristan M. Sissung, H.m. Pressler, D.k. Price, William D. FiggAbstract:A report by Wright and colleagues evaluated genetic variation in SLCO1B3 and SLCO2B1 versus outcomes in prostate cancer ([1][1]). Their major findings were as follows: (i) SLCO1B3 and SLCO2B1 were highly expressed in castration-resistant prostate cancer metastases versus untreated controls; (ii) no
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Expression of OATP Family Members in Hormone-Related Cancers: Potential Markers of Progression
PloS one, 2011Co-Authors: Heather M. Pressler, Tristan M. Sissung, David Venzon, Douglas K. Price, William D. FiggAbstract:The organic anion transporting polypeptide (OATP) family of transporters has been implicated in prostate cancer disease progression probably by transporting hormones or drugs. In this study, we aimed to elucidate the expression, frequency, and relevance of OATPs as a biomarker in hormone-dependent cancers. We completed a study examining SLCO1B3, SLCO1B1 and SLCO2B1 mRNA expression in 381 primary, independent patient samples representing 21 cancers and normal tissues. From a separate cohort, protein expression of OATP1B3 was examined in prostate, colon, and bladder tissue. Based on expression frequency, SLCO2B1 was lower in liver cancer (P = 0.04) which also trended lower with decreasing differentiation (P = 0.004) and lower magnitude in pancreatic cancer (P = 0.05). SLCO2B1 also had a higher frequency in thyroid cancer (67%) than normal (0%) and expression increased with stage (P = 0.04). SLCO1B3 was expressed in 52% of cancerous prostate samples and increased SLCO1B3 expression trended with higher Gleason score (P = 0.03). SLCO1B3 expression was also higher in testicular cancer (P = 0.02). SLCO1B1 expression was lower in liver cancer (P = 0.04) which trended lower with liver cancer grade (P = 0.0004) and higher with colon cancer grade (P = 0.05). Protein expression of OATP1B3 was examined in normal and cancerous prostate, colon, and bladder tissue samples from an independent cohort. The results were similar to the transcription data, but showed distinct localization. OATPs correlate to differentiation in certain hormone-dependent cancers, thus may be useful as biomarkers for assessing clinical treatment and stage of disease.
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Effect of SLCO1B3 Haplotype on Testosterone Transport and Clinical Outcome in Caucasian Patients with Androgen-Independent Prostatic Cancer
Clinical cancer research : an official journal of the American Association for Cancer Research, 2008Co-Authors: Akinobu Hamada, Tristan M. Sissung, David Venzon, Douglas K. Price, Romano Danesi, Cindy H. Chau, Nima Sharifi, Kenji Maeda, Keisuke Nagao, Alex SparreboomAbstract:Purpose: The organic anion transporter OATP1B3, encoded by SLCO1B3, is involved in the transport of steroid hormones. However, its role in testosterone uptake and clinical outcome of prostatic cancer is unknown. This study examined (a) the SLCO1B3 genotype in cancer cells as well as the uptake of testosterone by cells transfected with genetic variants of SLCO1B3; (b) the expression of OATP1B3 in normal prostate, benign prostatic hyperplasia, and prostatic cancer; and (c) the role of SLCO1B3 haplotype on clinical outcome of Caucasian patients with androgen-independent prostatic cancer. Experimental Design:SLCO1B3 genotype was assessed in the NCI-60 panel of tumor cells by sequencing, whereas testosterone transport was analyzed in Cos-7 cells transfected with WT, 334G, and 699A SLCO1B3 variants. OATP1B3 expression in prostatic tissues was examined by fluorescence microscopy, and the relationship between SLCO1B3 haplotypes and survival was examined in patients. Results: Cells transfected with wild-type (334T/699G) SLCO1B3, or with a vector containing either the 334G or 699A variants, actively transported testosterone, whereas its uptake was impaired in cells transfected with a gene carrying both 334G and 699A single nucleotide polymorphisms. Prostatic cancer overexpresses OATP1B3 compared with normal or benign hyperplastic tissue; patients with SLCO1B3 334GG/699AA haplotype showed longer median survival (8.5 versus 6.4 years; P = 0.020) and improved survival probability at 10 years (42% versus 23%; P Conclusions: The common SLCO1B3 GG/AA haplotype is associated with impaired testosterone transport and improved survival in patients with prostatic cancer.
William D. Figg - One of the best experts on this subject based on the ideXlab platform.
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Abstract A069: Mechanisms governing the transcriptional regulation of the liver-specific transporter OATP1B3 in prostate cancer
Cellular Responses to Therapy, 2019Co-Authors: Roberto H. Barbier, Tristan M. Sissung, Jonathan D. Strope, Edel M. Mccrea, Douglas K. Price, Cindy H. Chau, Phoebe A. Huang, William D. FiggAbstract:Background: The testosterone uptake transporter OATP1B3 is expressed de novo in prostate tumors and SLCO1B3 gene (encoding OATP1B3) variants are associated with clinical outcomes in patients with prostate cancer receiving androgen deprivation therapy (ADT) and in castration-resistant disease. These findings support the role of OATP1B3 as a major physiologic contributor to androgen distribution and a contributor to resistance to ADT. We have previously shown CBP/p300-mediated SLCO1B3 expression; however, specific transcriptional regulation of de novo expression remains to be elucidated. We characterized the SLCO1B3 promoter in order to better understand the regulatory mechanisms that govern its expression in prostate cancer. Methods: Functional analysis of the SLCO1B3 promoter was conducted using 5’ deletion mutagenesis. Transcriptional activity of the SLCO1B3 gene was measured using the SLCO1B3 promoter-luciferase reporter plasmids, transient transfections and luciferase reporter assays. Promoter activity was modulated by co-transfection with the p300 expression plasmid or treatment with various p300 inhibitor compounds (chetomin, HATi II, or C646). Results: We detected different transcriptional profiles across multiple prostate cancer cells (22Rv1, LNCaP, PC3) and identified a conserved domain responsible for SLCO1B3 transcriptional activity. Variable transcriptional changes in response to p300 inhibitor treatments were observed in both the conserved domain plasmid and the full-length reporter with the HATi II compound showing a consistent 2 to 3-fold increase in luciferase activity. Putative transcription factor binding sites are being evaluated by site-directed mutagenesis to determine potential regulatory elements involved in transcriptional activity of the gene. Conclusions: Our data suggest that several multi-protein transcription factor complexes assemble at distinct regulatory elements in the SLCO1B3 promoter, driving tissue-specific expression of OATP1B3 in prostate cancer. Understanding the underlying regulatory mechanisms of OATP1B3 expression and the transporter’s role in prostate cancer progression will aid in its development as a potential therapeutic target. Citation Format: Roberto H Barbier, Edel M McCrea, Jonathan D Strope, Phoebe A Huang, Tristan M Sissung, Douglas K Price, Cindy H Chau, William D Figg. Mechanisms governing the transcriptional regulation of the liver-specific transporter OATP1B3 in prostate cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A069. doi:10.1158/1535-7163.TARG-19-A069
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SLCO Transport Genes in Prostate Cancer—Letter
Cancer Epidemiology Biomarkers & Prevention, 2011Co-Authors: Tristan M. Sissung, H.m. Pressler, D.k. Price, William D. FiggAbstract:A report by Wright and colleagues evaluated genetic variation in SLCO1B3 and SLCO2B1 versus outcomes in prostate cancer ([1][1]). Their major findings were as follows: (i) SLCO1B3 and SLCO2B1 were highly expressed in castration-resistant prostate cancer metastases versus untreated controls; (ii) no
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Expression of OATP Family Members in Hormone-Related Cancers: Potential Markers of Progression
PloS one, 2011Co-Authors: Heather M. Pressler, Tristan M. Sissung, David Venzon, Douglas K. Price, William D. FiggAbstract:The organic anion transporting polypeptide (OATP) family of transporters has been implicated in prostate cancer disease progression probably by transporting hormones or drugs. In this study, we aimed to elucidate the expression, frequency, and relevance of OATPs as a biomarker in hormone-dependent cancers. We completed a study examining SLCO1B3, SLCO1B1 and SLCO2B1 mRNA expression in 381 primary, independent patient samples representing 21 cancers and normal tissues. From a separate cohort, protein expression of OATP1B3 was examined in prostate, colon, and bladder tissue. Based on expression frequency, SLCO2B1 was lower in liver cancer (P = 0.04) which also trended lower with decreasing differentiation (P = 0.004) and lower magnitude in pancreatic cancer (P = 0.05). SLCO2B1 also had a higher frequency in thyroid cancer (67%) than normal (0%) and expression increased with stage (P = 0.04). SLCO1B3 was expressed in 52% of cancerous prostate samples and increased SLCO1B3 expression trended with higher Gleason score (P = 0.03). SLCO1B3 expression was also higher in testicular cancer (P = 0.02). SLCO1B1 expression was lower in liver cancer (P = 0.04) which trended lower with liver cancer grade (P = 0.0004) and higher with colon cancer grade (P = 0.05). Protein expression of OATP1B3 was examined in normal and cancerous prostate, colon, and bladder tissue samples from an independent cohort. The results were similar to the transcription data, but showed distinct localization. OATPs correlate to differentiation in certain hormone-dependent cancers, thus may be useful as biomarkers for assessing clinical treatment and stage of disease.
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Pharmacogenetics of organic anion transporting peptides (OATP): An association of a SLCO1B3 polymorphism with the overall survival in white Caucasian patients with androgen independent prostate cancer
Journal of Clinical Oncology, 2007Co-Authors: Akinobu Hamada, Tristan M. Sissung, David Venzon, Douglas K. Price, W. L. Duhut, William D. FiggAbstract:5118 Background: Steroid hormone have been implicated in playing a fundamental role in pathogenesis of prostate cancer and several studies have reported an association between clinical outcome and polymorphism of genes involved in steroid metabolism. Recently we observed that polymorphic enzyme CYP17 which influences the rate-limiting steps in androgen biosynthesis was associated with overall survival. However, the effect of genetic variation on the transport of steroid hormones remains unknown. The purpose of this study was to evaluate the association between clinical outcomes in patients with androgen independent prostate cancer, and polymorphism in the SLCO1B3 gene that are potentially important in the differential uptake of steroid hormones. Methods: One hundred seventy nine white Caucasian patients with androgen independent prostate cancer were enrolled in this study. The duration of survival was computed from the date of prostate cancer diagnosis until the date of death or last follow-up. The SLCO1B...
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Variants in the SLCO1B3 gene : Interethnic distribution and association with paclitaxel pharmacokinetics
Clinical pharmacology and therapeutics, 2007Co-Authors: Nicola F. Smith, Howard L Mcleod, William D. Figg, Akinobu Hamada, Steven Marsh, Tiffany J. Scott-horton, Stephan Mielke, Klaus Mross, Jaap Verweij, Alex SparreboomAbstract:To explore retrospectively the relationships between paclitaxel pharmacokinetics and three known, non-synonymous single-nucleotide polymorphisms (SNPs) in SLCO1B3, the gene encoding organic anion transporting polypeptide (OATP)1B3. Accumulation of [(3)H]paclitaxel was studied in Xenopus laevis oocytes injected with cRNA of Oatp1b2, OATP1A2, OATP1B1, OATP1B3, OAT1, OAT3, OCT1, and NTCP. The 334T>G (Ser112Ala), 699G>A (Met233Ile), and 1564G>T (Gly522Cys) loci of SLCO1B3 were screened in 475 individuals from five ethnic groups and 90 European Caucasian cancer patients treated with paclitaxel. Only OATP1B3 was capable of transporting paclitaxel to a significant extent (P=0.003). The 334T>G and 699G>A SNPs were less common in the African-American and Ghanaian populations (P 0.3). The studied SNPs in SLCO1B3 appear to play a limited role in the disposition of paclitaxel, although their clinical significance in other ethnic populations remains to be investigated.