@misc{KammererKuepper, author = {Kammerer, Sarah and K{\"u}pper, Jan-Heiner}, title = {Human Hepatocyte Systems for in vitro Toxicology Analysis.}, series = {Journal of Cellular Biotechnology}, volume = {3}, journal = {Journal of Cellular Biotechnology}, number = {2}, issn = {2352-3697}, doi = {10.3233/JCB-179012}, pages = {85 -- 93}, language = {en} } @misc{KammererKuepper, author = {Kammerer, Sarah and K{\"u}pper, Jan-Heiner}, title = {Optimized protocol for induction of cytochrome P450 enzymes 1A2 and 3A4 in human primary-like hepatocyte cell strain HepaFH3 to study in vitro toxicology}, series = {Clinical Hemorheology and Microcirculation}, volume = {70}, journal = {Clinical Hemorheology and Microcirculation}, number = {4}, issn = {1386-0291}, doi = {10.3233/CH-189321}, pages = {563 -- 571}, language = {en} } @misc{SteinbrechtKoenigSchmidtkeetal., author = {Steinbrecht, Susanne and K{\"o}nig, Rosalie and Schmidtke, Kai-Uwe and Herzog, Natalie and Scheibner, Katrin and Kr{\"u}ger-Genge, Anne and Jung, Friedrich and Kammerer, Sarah and K{\"u}pper, Jan-Heiner}, title = {Metabolic activity testing can underestimate acute drug cytotoxicity as revealed by HepG2 cell clones overexpressing cytochrome P450 2C19 and 3A4}, series = {Toxicology}, volume = {412}, journal = {Toxicology}, issn = {0300-483X}, doi = {10.1016/j.tox.2018.11.008}, pages = {37 -- 47}, language = {en} } @misc{NowakKammererKuepper, author = {Nowak, Elisabeth and Kammerer, Sarah and K{\"u}pper, Jan-Heiner}, title = {ATP-based cell viability assay is superior to trypan blue exclusion and XTT assay in measuring cytotoxicity of anticancer drugs Taxol and Imatinib, and proteasome inhibitor MG-132 on human hepatoma cell line HepG2.}, series = {Clinical Hemorheology and Microcirculation}, volume = {69}, journal = {Clinical Hemorheology and Microcirculation}, number = {1-2}, issn = {1386-0291}, doi = {10.3233/CH-189120}, pages = {327 -- 336}, language = {en} } @misc{HofmanSorfVagiannisetal., author = {Hofman, Jakub and Sorf, Ales and Vagiannis, Dimitrios and Sucha, Simona and Novotna, Eva and Kammerer, Sarah and K{\"u}pper, Jan-Heiner and Ceckova, Martina and Staud, Frantisek}, title = {Interactions of Alectinib with Human ATP-Binding Cassette Drug Efflux Transporters and Cytochrome P450 Biotransformation Enzymes: Effect on Pharmacokinetic Multidrug Resistance}, series = {Drug Metabolism and Disposition}, volume = {47}, journal = {Drug Metabolism and Disposition}, number = {7}, issn = {1521-009X}, doi = {10.1124/dmd.119.086975}, pages = {699 -- 709}, language = {en} } @misc{SteinbrechtKammererKuepper, author = {Steinbrecht, Susanne and Kammerer, Sarah and K{\"u}pper, Jan-Heiner}, title = {HepG2 cells with recombinant cytochrome P450 enzyme overexpression: Their use and limitation as in vitro liver model}, series = {Journal of Cellular Biotechnology}, volume = {5}, journal = {Journal of Cellular Biotechnology}, number = {1}, issn = {2352-3697}, doi = {10.3233/JCB-189013}, pages = {55 -- 64}, language = {en} } @misc{HofmanSorfVagiannisetal., author = {Hofman, Jakub and Sorf, Ales and Vagiannis, Dimitrios and Sucha, Simona and Kammerer, Sarah and K{\"u}pper, Jan-Heiner and Chen, Si and Guo, Lei and Ceckova, Martina and Staud, Frantisek}, title = {Brivanib Exhibits Potential for Pharmacokinetic Drug-Drug Interactions and the Modulation of Multidrug Resistance through the Inhibition of Human ABCG2 Drug Efflux Transporter and CYP450 Biotransformation Enzymes}, series = {Molecular Pharmaceutics}, volume = {16}, journal = {Molecular Pharmaceutics}, number = {11}, doi = {10.1021/acs.molpharmaceut.9b00361}, pages = {4436 -- 4450}, language = {en} } @misc{SchulzKammererKuepper, author = {Schulz, Christian and Kammerer, Sarah and K{\"u}pper, Jan-Heiner}, title = {NADPH-cytochrome P450 reductase expression and enzymatic activity in primary-like human hepatocytes and HepG2 cells for in vitro biotransformation studies}, series = {Clinical Hemorheology and Microcirculation}, volume = {73}, journal = {Clinical Hemorheology and Microcirculation}, number = {1}, issn = {1386-0291}, doi = {10.3233/CH-199226}, pages = {249 -- 260}, language = {en} } @misc{UhligGehreKammereretal., author = {Uhlig, Katja and Gehre, Christian P. and Kammerer, Sarah and K{\"u}pper, Jan-Heiner and Coleman, D. and P{\"u}schel, G. and Duschl, Claus}, title = {Real-time monitoring of oxygen consumption of hepatocytes in a microbioreactor}, series = {Toxicology Letters}, volume = {295}, journal = {Toxicology Letters}, number = {Supplement 1}, issn = {0378-4274}, doi = {10.1016/j.toxlet.2018.06.652}, pages = {S115}, language = {en} } @misc{SteinbrechtPfeiferHerzogetal., author = {Steinbrecht, Susanne and Pfeifer, Nadine and Herzog, Natalie and Katzenberger, Nadine and Schulz, Christian and Kammerer, Sarah and K{\"u}pper, Jan-Heiner}, title = {HepG2-1A2 C2 and C7: Lentivirus vector-mediated stable and functional overexpression of cytochrome P450 1A2 in human hepatoblastoma cells}, series = {Toxicology Letters}, volume = {319}, journal = {Toxicology Letters}, issn = {0378-4274}, doi = {10.1016/j.toxlet.2019.11.006}, pages = {155 -- 159}, abstract = {Novel HepG2 cell clones 1A2 C2 and 1A2 C7 were independently generated by lentiviral transduction to functionally overexpress cytochrome P450 1A2 (CYP1A2). We found similar and stable CYP1A2 transcript and protein levels in both cell clones leading to specific enzyme activities of about 370 pmol paracetamol x min-1 x mg-1 protein analyzed by phenacetin conversion. Both clones showed dramatically increased sensitivity to the hepatotoxic compound aflatoxin B1 (EC50<100 nM) when compared to parental HepG2 cells (EC50 ∼5 μM). Thus, newly established cell lines are an appropriate tool to study metabolism and toxicity of substances depending on conversion by CYP1A2.}, language = {en} } @misc{LauRangarajanKruegerGengeetal., author = {Lau, S. and Rangarajan, R. and Kr{\"u}ger-Genge, Anne and Braune, Steffen and Kammerer, Sarah and K{\"u}pper, Jan-Heiner and Lendlein, Andreas and Jung, Friedrich}, title = {Effects of acrolein in comparison to its prodrug cyclophosphamide on human primary endothelial cells in vitro}, series = {Toxicology in Vitro}, volume = {62}, journal = {Toxicology in Vitro}, issn = {0887-2333}, doi = {10.1016/j.tiv.2019.104685}, pages = {8}, abstract = {Cyclophosphamide (CPA) is one of the most successful anticancer prodrugs that becomes effective after biotransformation in the liver resulting in the toxic metabolite acrolein. Cancer is often accompanied by thromboembolic events, which might be a result of dysfunctional endothelial cells due to CPA treatment. Here, the effect of 1 mM CPA or acrolein (10/50/100/500 μM) on human umbilical vein endothelial cells (HUVECs) was analyzed after two days of treatment. The addition of CPA or 10 μM acrolein did not affect HUVECs. However, concentrations of 100 μM and 500 μM acrolein significantly reduced the number of adherent cells by 86 ± 13\% and 99 ± 1\% and cell viability by 51 ± 29\% and 93 ± 8\% compared to the control. Moreover, pronounced stress fibers as well as multiple nuclei were observed and von Willebrand factor (vWF) was completely released. Lactate dehydrogenase was 8.5 ± 7.0-fold and 252.9 ± 42.9-fold increased showing a loss of cell membrane integrity. The prostacyclin and thromboxane secretion was significantly increased by the addition of 500 μM acrolein (43.1 ± 17.6-fold and 246.4 ± 106.3-fold) indicating cell activation/pertubation. High doses of acrolein led to HUVEC death and loss of vWF production. This effect might be associated with the increased incidence of thromboembolic events in cancer patients treated with high doses of CPA.}, language = {en} } @misc{GehreFlechnerKammereretal., author = {Gehre, Christian P. and Flechner, Marie and Kammerer, Sarah and K{\"u}pper, Jan-Heiner and Coleman, Charles Dominic and P{\"u}schel, Gerhard Paul and Uhlig, Katja and Duschl, Claus}, title = {Real time monitoring of oxygen uptake of hepatocytes in a microreactor using optical microsensors}, series = {Scientific Reports}, volume = {10}, journal = {Scientific Reports}, issn = {2045-2322}, doi = {10.1038/s41598-020-70785-6}, abstract = {Most in vitro test systems for the assessment of toxicity are based on endpoint measurements and cannot contribute much to the establishment of mechanistic models, which are crucially important for further progress in this field. Hence, in recent years, much effort has been put into the development of methods that generate kinetic data. Real time measurements of the metabolic activity of cells based on the use of oxygen sensitive microsensor beads have been shown to provide access to the mode of action of compounds in hepatocytes. However, for fully exploiting this approach a detailed knowledge of the microenvironment of the cells is required. In this work, we investigate the cellular behaviour of three types of hepatocytes, HepG2 cells, HepG2-3A4 cells and primary mouse hepatocytes, towards their exposure to acetaminophen when the availability of oxygen for the cell is systematically varied. We show that the relative emergence of two modes of action, one NAPQI dependent and the other one transient and NAPQI independent, scale with expression level of CYP3A4. The transient cellular response associated to mitochondrial respiration is used to characterise the influence of the initial oxygen concentration in the wells before exposure to acetaminophen on the cell behaviour. A simple model is presented to describe the behaviour of the cells in this scenario. It demonstrates the level of control over the role of oxygen supply in these experiments. This is crucial for establishing this approach into a reliable and powerful method for the assessment of toxicity.}, language = {en} } @misc{SteinbrechtKiebistKoenigetal., author = {Steinbrecht, Susanne and Kiebist, Jan and K{\"o}nig, Rosalie and Thiessen, Markus and Schmidtke, Kai-Uwe and Kammerer, Sarah and K{\"u}pper, Jan-Heiner and Scheibner, Katrin}, title = {Synthesis of cyclophosphamide metabolites by a peroxygenase from Marasmius rotula for toxicological studies on human cancer cells}, series = {AMB Express}, volume = {10}, journal = {AMB Express}, issn = {2191-0855}, doi = {10.1186/s13568-020-01064-w}, pages = {13}, abstract = {Cyclophosphamide (CPA) represents a widely used anti-cancer prodrug that is converted by liver cytochrome P450 (CYP) enzymes into the primary metabolite 4-hydroxycyclophosphamide (4-OH-CPA), followed by non-enzymatic generation of the bioactive metabolites phosphoramide mustard and acrolein. The use of human drug metabolites as authentic standards to evaluate their toxicity is essential for drug development. However, the chemical synthesis of 4-OH-CPA is complex and leads to only low yields and undesired side products. In past years, fungal unspecific peroxygenases (UPOs) have raised to powerful biocatalysts. They can exert the identical selective oxyfunctionalization of organic compounds and drugs as known for CYP enzymes with hydrogen peroxide being used as sole cosubstrate. Herein, we report the efficient enzymatic hydroxylation of CPA using the unspecific peroxygenase from Marasmius rotula (MroUPO) in a simple reaction design. Depending on the conditions used the primary liver metabolite 4-OH-CPA, its tautomer aldophosphamide (APA) and the overoxidized product 4-ketocyclophosphamide (4-keto-CPA) could be obtained. Using a kinetically controlled approach 4-OH-CPA was isolated with a yield of 32\% (purity > 97.6\%). Two human cancer cell lines (HepG2 and MCF-7) were treated with purified 4-OH-CPA produced by MroUPO (4-OH-CPAUPO). 4-OH-CPAUPO-induced cytotoxicity as measured by a luminescent cell viability assay and its genotoxicity as measured by γH2AX foci formation was not significantly different to the commercially available standard. The high yield of 4-OH-CPAUPO and its biological activity demonstrate that UPOs can be efficiently used to produce CYP-specific drug metabolites for pharmacological assessment.}, language = {en} } @misc{VagiannisNovotnaSkarkaetal., author = {Vagiannis, Dimitrios and Novotna, Eva and Skarka, Adam and Kammerer, Sarah and K{\"u}pper, Jan-Heiner and Chen, Si and Guo, Lei and Staud, Frantisek and Hofman, Jakub}, title = {Ensartinib (X-396) Effectively Modulates Pharmacokinetic Resistance Mediated by ABCB1 and ABCG2 Drug Efflux Transporters and CYP3A4 Biotransformation Enzyme}, series = {Cancers}, volume = {12}, journal = {Cancers}, number = {4}, issn = {2072-6694}, doi = {10.3390/cancers12040813}, pages = {27}, abstract = {Ensartinib (X-396) is a promising tyrosine kinase inhibitor currently undergoing advanced clinical evaluation for the treatment of non-small cell lung cancer. In this work, we investigate possible interactions of this promising drug candidate with ATP-binding cassette (ABC) drug efflux transporters and cytochrome P450 biotransformation enzymes (CYPs), which play major roles in multidrug resistance (MDR) and pharmacokinetic drug-drug interactions (DDIs). Accumulation studies showed that ensartinib is a potent inhibitor of ABCB1 and ABCG2 transporters. Additionally, incubation experiments with recombinant CYPs showed that ensartinib significantly inhibits CYP3A4 and CYP2C9. Subsequent molecular docking studies confirmed these findings. Drug combination experiments demonstrated that ensartinib synergistically potentiates the antiproliferative effects of daunorubicin, mitoxantrone, and docetaxel in ABCB1, ABCG2, and CYP3A4-overexpressing cellular models, respectively. Advantageously, ensartinib's antitumor efficiency was not compromised by the presence of MDR-associated ABC transporters, although it acted as a substrate of ABCB1 in Madin-Darby Canine Kidney II (MDCKII) monolayer transport assays. Finally, we demonstrated that ensartinib had no significant effect on the mRNA-level expression of examined transporters and enzymes in physiological and lung tumor cellular models. In conclusion, ensartinib may perpetrate clinically relevant pharmacokinetic DDIs and modulate ABCB1-, ABCG2-, and CYP3A4-mediated MDR. The in vitro findings presented here will provide a valuable foundation for future in vivo investigations.}, language = {en} } @misc{BrauneKruegerGengeKammereretal., author = {Braune, Steffen and Kr{\"u}ger-Genge, Anne and Kammerer, Sarah and Jung, Friedrich and K{\"u}pper, Jan-Heiner}, title = {Phycocyanin from Arthrospira platensis as Potential Anti-Cancer Drug: Review of In Vitro and In Vivo Studies}, series = {Life}, volume = {11}, journal = {Life}, number = {2}, doi = {10.3390/life11020091}, pages = {91}, language = {en} } @misc{VagiannisZhangBudagagaetal., author = {Vagiannis, Dimitrios and Zhang, Yu and Budagaga, Youssif and Novotna, Eva and Skarka, Adam and Kammerer, Sarah and K{\"u}pper, Jan-Heiner and Hofman, Jakub}, title = {Alisertib shows negligible potential for perpetrating pharmacokinetic drug-drug interactions on ABCB1, ABCG2 and cytochromes P450, but acts as dual-activity resistance modulator through the inhibition of ABCC1 transporter}, series = {Toxicology and Applied Pharmacology}, volume = {Vol. 434}, journal = {Toxicology and Applied Pharmacology}, issn = {0041-008X}, doi = {10.1016/j.taap.2021.115823}, pages = {13}, language = {en} } @misc{VagiannisBudagagaMorelletal., author = {Vagiannis, Dimitrios and Budagaga, Youssif and Morell, Anselm and Zhang, Yu and Novotna, Eva and Skarka, Adam and Kammerer, Sarah and K{\"u}pper, Jan-Heiner and Hanke, Ivo and Rozkoš, Tom{\´a}š and Hofman, Jakub}, title = {Tepotinib Inhibits Several Drug Efflux Transporters and Biotransformation Enzymes: The Role in Drug-Drug Interactions and Targeting Cytostatic Resistance In Vitro and Ex Vivo}, series = {International Journal of Molecular Sciences}, volume = {22}, journal = {International Journal of Molecular Sciences}, number = {21}, issn = {1422-0067}, doi = {10.3390/ijms222111936}, language = {en} } @misc{KruegerGengeKoehlerLaubeetal., author = {Kr{\"u}ger-Genge, Anne and K{\"o}hler, Susanne and Laube, Markus and Haileka, Vanessa and Lemm, Sandy and Majchrzak, Karolina and Kammerer, Sarah and Schulz, Christian and Storsberg, Joachim and Pietzsch, Jens and K{\"u}pper, Jan-Heiner and Jung, Friedrich}, title = {Anti-Cancer Prodrug Cyclophosphamide Exerts Thrombogenic Effects on Human Venous Endothelial Cells Independent of CYP450 Activation—Relevance to Thrombosis}, series = {Cells}, volume = {12}, journal = {Cells}, number = {15}, issn = {2073-4409}, doi = {10.3390/cells12151965}, abstract = {Cancer patients are at a very high risk of serious thrombotic events, often fatal. The causes discussed include the detachment of thrombogenic particles from tumor cells or the adverse effects of chemotherapeutic agents. Cytostatic agents can either act directly on their targets or, in the case of a prodrug approach, require metabolization for their action. Cyclophosphamide (CPA) is a widely used cytostatic drug that requires prodrug activation by cytochrome P450 enzymes (CYP) in the liver. We hypothesize that CPA could induce thrombosis in one of the following ways: (1) damage to endothelial cells (EC) after intra-endothelial metabolization; or (2) direct damage to EC without prior metabolization. In order to investigate this hypothesis, endothelial cells (HUVEC) were treated with CPA in clinically relevant concentrations for up to 8 days. HUVECs were chosen as a model representing the first place of action after intravenous CPA administration. No expression of CYP2B6, CYP3A4, CYP2C9 and CYP2C19 was found in HUVEC, but a weak expression of CYP2C18 was observed. CPA treatment of HUVEC induced DNA damage and a reduced formation of an EC monolayer and caused an increased release of prostacyclin (PGI2) and thromboxane (TXA) associated with a shift of the PGI2/TXA balance to a prothrombotic state. In an in vivo scenario, such processes would promote the risk of thrombus formation.}, language = {en} } @misc{KammererNowakMantkeetal., author = {Kammerer, Sarah and Nowak, Elisabeth and Mantke, Ren{\´e} and Jung, Friedrich and K{\"u}pper, Jan-Heiner}, title = {In vitro simulation of the liver first-pass effect with biotransformation-competent HepG2 cells to study effects of MG-132 on liver and cancer cells}, series = {Clinical Hemorheology and Microcirculation}, volume = {86}, journal = {Clinical Hemorheology and Microcirculation}, number = {1-2}, issn = {1386-0291}, doi = {10.3233/CH-238108}, pages = {159 -- 168}, abstract = {BACKGROUND: Liver biotransformation is the major route for drug metabolism in humans, often catalysed by cytochrome P450 (CYP) enzymes. This first-pass effect can lead to hepatotoxicity and influences the bioavailability of drugs. OBJECTIVE: We aimed to establish in vitro culture systems simulating the liver first-pass to study effects of the proteasome inhibitor MG-132 simultaneously on hepatocytes and cancer cells. METHODS: The first-pass effect was simulated by conditioned medium transfer (CMT) from pre-treated HepG2 CYP3A4-overexpressing cells to either pancreatic cancer cell line PANC-1 or primary colon cancer cells, and by indirect co-culture (CC) of liver and cancer cells in a shared medium compartment. Experimental proteasome inhibitor MG-132 was used as test substance as it is detoxified by CYP3A4. RESULTS: Cancer cells showed higher viabilities in the first-pass simulation by CMT and CC formats when compared to monocultures indicating effective detoxification of MG-132 by HepG2 CYP3A4-overexpressing cells. HepG2-CYP3A4 cells showed reduced viabilites after treatment with MG-132. CONCLUSIONS: We successfully established two different culture systems to simulate the liver first-pass effect in vitro. Such systems easily allow to study drug effects simultaneously on liver and on target cancer cells. They are of great value in pre-clinical cancer research, pharmaceutical research and drug development.}, language = {en} }