First-in-class MKK4 inhibitors enhance liver regeneration and prevent liver failure

Diminished hepatocyte regeneration is a key feature of acute and chronic liver diseases and after extended liver resections, resulting in the inability to maintain or restore a sufficient functional liver mass. Therapies to restore hepatocyte regeneration are lacking, making liver transplantation the only curative option for end-stage liver disease. Here, we report on the structure-based development and characterization (nuclear magnetic resonance [NMR] spectroscopy) of first-in-class small molecule inhibitors of the dual-specificity kinase MKK4 (MKK4i). MKK4i increased liver regeneration upon hepatectomy in murine and porcine models, allowed for survival of pigs in a lethal 85% hepatectomy model, and showed antisteatotic and antifibrotic effects in liver disease mouse models. A first-in-human phase I trial (European Union Drug Regulating Authorities Clinical Trials [EudraCT] 2021-000193-28) with the clinical candidate HRX215 was conducted and revealed excellent safety and pharmacokinetics. Clinical trials to probe HRX215 for prevention/treatment of liver failure after extensive oncological liver resections or after transplantation of small grafts are warranted.

Small-molecule inhibition of MAP2K4 is synergistic with RAS inhibitors in KRAS-mutant cancers

The Kirsten rat sarcoma viral oncogene homologue KRAS is among the most commonly mutated oncogenes in human cancers, thus representing an attractive target for precision oncology. The approval for clinical use of the first selective inhibitors of G12C mutant KRAS therefore holds great promise for cancer treatment. However, despite initial encouraging clinical results, the overall survival benefit that patients experience following treatment with these inhibitors has been disappointing to date, pointing toward the need to develop more powerful combination therapies. Here, we show that responsiveness to KRASG12C and pan-RAS inhibitors in KRAS-mutant lung and colon cancer cells is limited by feedback activation of the parallel MAP2K4-JNK-JUN pathway. Activation of this pathway leads to elevated expression of receptor tyrosine kinases that reactivate KRAS and its downstream effectors in the presence of drug. We find that the combination of sotorasib, a drug targeting KRASG12C, and the MAP2K4 inhibitor HRX-0233 prevents this feedback activation and is highly synergistic in a panel of KRASG12C-mutant lung and colon cancer cells. Moreover, combining HRX-0233 and sotorasib is well-tolerated and resulted in durable tumor shrinkage in mouse xenografts of human lung cancer cells, suggesting a therapeutic strategy for KRAS-driven cancers.

Detailed stratified GWAS analysis for severe COVID-19 in four European populations

Given the highly variable clinical phenotype of Coronavirus disease 2019 (COVID-19), a deeper analysis of the host genetic contribution to severe COVID-19 is important to improve our understanding of underlying disease mechanisms. Here, we describe an extended genome-wide association meta-analysis of a well-characterized cohort of 3255 COVID-19 patients with respiratory failure and 12 488 population controls from Italy, Spain, Norway and Germany/Austria, including stratified analyses based on age, sex and disease severity, as well as targeted analyses of chromosome Y haplotypes, the human leukocyte antigen region and the SARS-CoV-2 peptidome. By inversion imputation, we traced a reported association at 17q21.31 to a ~0.9-Mb inversion polymorphism that creates two highly differentiated haplotypes and characterized the potential effects of the inversion in detail. Our data, together with the 5th release of summary statistics from the COVID-19 Host Genetics Initiative including non-Caucasian individuals, also identified a new locus at 19q13.33, including NAPSA, a gene which is expressed primarily in alveolar cells responsible for gas exchange in the lung.

Design and Synthesis of Highly Selective Brain Penetrant p38α Mitogen-Activated Protein Kinase Inhibitors

Stress-induced p38α mitogen-activated protein (MAP) kinase activation modulates cytokine overproduction and is associated with neuroinflammation and neurodegeneration. As a potential therapeutic approach, novel Skepinone-based p38α MAP kinase inhibitors were optimized to cross the blood-brain barrier via either amino acid transporters or hydrophobic diffusion. To enhance absorption from the oral route, we used methyl ester prodrugs of the active carboxy analogs. Of these, 3-(8-((2,4-difluorophenyl)amino)-5-oxo-10,11-dihydro-5H-dibenzo[a,d][7]annulene-3-carboxamido)propanoic acid (43; p38α, IC₅₀ = 5.5 nM) and 4-(8-((2,4-difluorophenyl)amino)-5-oxo-10,11-dihydro-5H-dibenzo[a,d][7]annulene-3-carboxamido)butanoic acid (44; p38α, IC₅₀ = 12 nM) had brain-to-plasma ratios of 1.4 and 4.4, respectively. Compound 70, 3-(8-((2-aminophenyl)amino)-5-oxo-10,11-dihydro-5H-dibenzo[a,d][7]annulene-3-carboxamido)propanoic acid (p38α, IC₅₀ = 1.0 nM), the Skepinone-N counterpart of 43, was most present in the mouse brain (brain-to-plasma ratio of 4.7; 0.4 mg/kg p.o., 2 h, 580 nmol/kg). Compounds 43, 44, and 70 were p38α-MAP-kinase-selective, metabolically stable, hERG nonbinding, and able to modulate IL-6 and TNF-α production in cell-based assays.

Design and synthesis of 1H-pyrazolo[3,4-b]pyridines targeting mitogen-activated protein kinase kinase 4 (MKK4) - A promising target for liver regeneration

Currently, the therapeutic options for treatment of liver failure are very limited. As mitogen-activated protein kinase kinase 4 (MKK4) has recently been identified by in vivo RNAi experiments to be a major regulator in hepatocyte regeneration, we pursued the development of a small molecule targeting this protein kinase. Starting from the approved BRAF^V600E inhibitor vemurafenib (8), that showed a high off-target affinity to MKK4 in an initial screening, we followed a scaffold-hopping approach, changing the core heterocycle from 1H-pyrrolo[2,3-b]pyridine to 1H-pyrazolo[2,3-b]pyridine (10). Affinity to MKK4 could be conserved while the selectivity against off-target protein kinases was slightly improved. Further modifications led to 58 and 59 showing high affinity to MKK4 in the low nanomolar range and excellent selectivity profile from mandatory multiparameter-optimization for the essential anti-targets (MKK7, JNK1) and off-targets (BRAF, MAP4K5, ZAK) in the MKK4 pathway. Herein we report the first selective MKK4 inhibitors in this class.

From off-to on-target: New BRAF-inhibitor-template-derived compounds selectively targeting mitogen activated protein kinase kinase 4 (MKK4)

The mitogen-activated protein kinase (MAP) kinase 4 (MKK4) was found to be a major regulator of liver regeneration and could be a valuable drug target addressing liver related diseases by restoring its intrinsic regenerative capacity. We report on the synthesis and optimization of novel MKK4 inhibitors following a target-hopping strategy from the FDA-approved BRAF^V600E inhibitor PLX4032 (8). Applying an iterative multi-parameter optimization process we carved out essential structural features yielding in compounds with a low nanomolar affinity for MKK4 and excellent selectivity profiles against the main off-targets MKK7 and JNK1, which, upon relevant inhibition, would totally abrogate the pro-regenerative effect of MKK4 inhibition, as well as against the off-targets MAP4K5, ZAK and BRAF with selectivity factors ranging from 40 to 430 for our best-balanced compounds 70 and 73.

Genomewide Association Study of Severe Covid-19 with Respiratory Failure

BACKGROUND

There is considerable variation in disease behavior among patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (Covid-19). Genomewide association analysis may allow for the identification of potential genetic factors involved in the development of Covid-19.

METHODS

We conducted a genomewide association study involving 1980 patients with Covid-19 and severe disease (defined as respiratory failure) at seven hospitals in the Italian and Spanish epicenters of the SARS-CoV-2 pandemic in Europe. After quality control and the exclusion of population outliers, 835 patients and 1255 control participants from Italy and 775 patients and 950 control participants from Spain were included in the final analysis. In total, we analyzed 8,582,968 single-nucleotide polymorphisms and conducted a meta-analysis of the two case-control panels.

RESULTS

We detected cross-replicating associations with rs11385942 at locus 3p21.31 and with rs657152 at locus 9q34.2, which were significant at the genomewide level (P<5×10-8) in the meta-analysis of the two case-control panels (odds ratio, 1.77; 95% confidence interval [CI], 1.48 to 2.11; P = 1.15×10-10; and odds ratio, 1.32; 95% CI, 1.20 to 1.47; P = 4.95×10-8, respectively). At locus 3p21.31, the association signal spanned the genes SLC6A20, LZTFL1, CCR9, FYCO1, CXCR6 and XCR1. The association signal at locus 9q34.2 coincided with the ABO blood group locus; in this cohort, a blood-group-specific analysis showed a higher risk in blood group A than in other blood groups (odds ratio, 1.45; 95% CI, 1.20 to 1.75; P = 1.48×10-4) and a protective effect in blood group O as compared with other blood groups (odds ratio, 0.65; 95% CI, 0.53 to 0.79; P = 1.06×10-5).

CONCLUSIONS

We identified a 3p21.31 gene cluster as a genetic susceptibility locus in patients with Covid-19 with respiratory failure and confirmed a potential involvement of the ABO blood-group system. (Funded by Stein Erik Hagen and others.).

Design and synthesis of novel fluorescently labeled analogs of vemurafenib targeting MKK4

The mitogen-activated protein kinase kinase 4 (MKK4) plays a key role in liver regeneration and is under investigation as a target for stimulating hepatocytes to increased proliferation. Therefore, new small molecules inhibiting MKK4 may represent a promising approach for treating acute and chronic liver diseases. Fluorescently labeled compounds are useful tools for high-throughput screenings of large compound libraries. Here we utilized the azaindole-based scaffold of FDA-approved BRAF inhibitor vemurafenib 1, which displays off-target activity on MKK4, as a starting point in our fluorescent compound design. Chemical variation of the scaffold and optimization led to a selection of fluorescent 5-TAMRA derivatives which possess high binding affinities on MKK4. Compound 45 represents a suitable tool compound for Fluorescence polarization assays to identify new small-molecule inhibitors of MKK4.

Die neue EU-Spirituosenverordnung und ihr neues Schutzsystem für geografische Angaben im Spirituosensektor und somit auch für Spirituosen weinbaulichen Ursprungs (z.B. Cognac)

Die neue Spirituosen-Verordnung (EU) 2019/787 regelt auch künftig produktspezifisch den Schutz von eingetragenen geografischen Angaben für Spirituosen mit Ursprung in der EU und in Drittstaaten (sog. Geoschutz), bringt jedoch eine Reihe von Änderungen mit sich, die weitgehend dem horizontalen Geoschutzsystem für sonstige Agrarprodukte und Lebensmittel, das in der Verordnung (EU) Nr. 1151/2012 verankert, entlehnt sind. So werden nicht nur die Begriffe „Produktspezifikation“ und „Einziges Dokument“ übernommen, sondern auch das zweistufige Eintragungsverfahren sowie die Vorschrift, dass nur noch private Schutzvereinigungen das Recht haben, Anträge auf Eintragung von g.A. zu stellen. Geografische Angaben sind bereits seit 1. Januar 1996 im WTO-Übereinkommen über handelsbezogene Aspekte des geistigen Eigentums (TRIPS) geschützt und sind seit 2015 durch die Genfer Akte auch in der Lissabonner Verbandsübereinkunft, die von der WIPO verwaltet wird, neben den geschützten und kontrollierten Ursprungsbezeichnungen als qualifizierte Herkunftsbezeichnungen international anerkannt.

A Diverse and Versatile Regiospecific Synthesis of Tetrasubstituted Alkylsulfanylimidazoles as p38α Mitogen-Activated Protein Kinase Inhibitors

An alternative strategy for the synthesis of 1-aryl- and 1-alkyl-2-methylsulfanyl-4-(4-fluorophenyl)-5-(pyridin-4-yl)imidazoles as potential p38α mitogen-activated protein kinase inhibitors is reported. The regioselective N-substitution of the imidazole ring was achieved by treatment of α-aminoketones with different aryl or alkyl isothiocyanates. In contrast to previously published synthesis routes starting from 2-amino-4-methylpyridine, the presented route is characterized by a higher flexibility and a lower number of steps. This strategy was also applied to access 1-alkyl-2-methylsulfanyl-5-(4-fluorophenyl)-4-(pyridin-4-yl)imidazoles in six steps starting from 2-chloro-4-methylpyridine.

From 2-Alkylsulfanylimidazoles to 2-Alkylimidazoles: An Approach towards Metabolically More Stable p38α MAP Kinase Inhibitors

In vitro and in vivo metabolism studies revealed that 2-alkylsulfanylimidazole ML3403 (4-(5-(4-fluorophenyl)-2-(methylthio)-1H-imidazol-4-yl)-N-(1-phenylethyl)pyridin-2-amine) undergoes rapid oxidation to the sulfoxide. Replacing the sulfur atom present in the two potent p38α mitogen-activated protein (MAP) kinase inhibitors ML3403 and LN950 (2-((5-(4-fluorophenyl)-4-(2-((3-methylbutan-2-yl)amino)pyridin-4-yl)-1H-imidazol-2-yl)thio)ethan-1-ol) by a methylene group resulted in 2-alkylimidazole derivatives 1 and 2, respectively, having a remarkably improved metabolic stability. The 2-alkylimidazole analogs 1 and 2 showed 20% and 10% biotransformation after 4 h of incubation with human liver microsomes, respectively. They display a 4-fold increased binding affinity towards the target kinase as well as similar in vitro potency and ex vivo efficacy relative to their 2-alkylsulfanylimidazole counterparts ML3403 and LN950. For example, 2-alkylimidazole 2, the analog of LN950, inhibits both the p38α MAP kinase as well as the LPS-stimulated tumor necrosis factor-α release from human whole blood in the low double-digit nanomolar range.

Exploring the Molecular-Level Architecture of the Active Compounds in Liquisolid Drug Delivery Systems Based on Mesoporous Silica Particles: Old Tricks for New Challenges

A general, easy-to-implement strategy for mapping the structure of organic phases integrated in mesoporous silica drug delivery devices is presented. The approach based on a few straightforward solid-state NMR techniques has no limitations regarding concentrations of the active compounds and enables straightforward discrimination of various organic phases. This way, among a range of typical arrangements of the active compounds and solvent molecules, a unique, previously unknown organogel phase of the self-assembled tapentadol in glucofurol as a solvent was unveiled and clearly identified. Subsequently, with an aid of 2D ¹H-¹H MAS NMR and high-level quantum-chemical calculations this uncommon low-molecular-weight organogel phase, existing exclusively in the porous system of the silica carrier, was described in detail. The optimized model revealed the tendency of tapentadol molecules to form hydrophobic arrangements through -OH···π interactions combined with π-π stacking occurring in the core of API aggregates, thus precluding the formation of hydrogen bonds with the solvent. Overall, the proposed experimental approach allows for clear discrimination of a variety of local structures of active compounds loaded in mesoporous silica drug delivery devices in reasonably short time being applicable for advancement of novel drug delivery systems in pharmaceutical industry.

Über die Änderung der Aktivität der alkalischen und sauren Phosphatase und des Glykogengehalts im Muskel der mit Coxsackie-Virus infizierten Säuglingsmaus

Bei der Säuglingsmaus wird nach Infektion mit dem Coxsackie-Virus A2, neben einer alkalischen Phosphatase eine saure Phosphatase in Freiheit gesetzt, welche Na-β-Glycerophosphat und Phenylphosphat (Bayer) spaltet. Der Glykogengehalt der gelähmten Muskulatur ist signifikant erniedrigt. Nach Infektion mit dem Coxsackie-Virus A1 ist die Aktivität der alkalischen Phosphatase und der sauren Phosphatase im Muskel nicht gesteigert, das Muskelglykogen ist gegenüber den Kontrollen nur geringfügig vermindert. Ein Freiwerden von Phosphatase infolge Muskelzerfalls nach Infektion mit Coxsackie-Virus A2 ist daher unwahrscheinlich. Ein direktes Eingreifen dieses Virusstammes in den Kohlenhydratstoffwechsel des Muskels wird diskutiert.

Bestimmungen des Tryptophangehaltes verschiedener Rassen der Mehlmotte Ephestia Kühniella als Beitrag zur Analyse der Genwirkungen

In Bestätigung der Befunde von E. Caspari wird nachgewiesen, daß die Proteine der Larven und Motten von aa-Ephestia-Mutanten einen signifikant höheren Gehalt an Tryptophan enthalten als die der a+a+-Wildform. Dieser erhöhte Tryptophangehalt ist bei aa-Mutanten mit verschiedener Augenfarbnuance von gleicher Größenordnung und wird durch Unterschiede in der Tryptophankonzentration des Futters nicht wesentlich beeinflußt. Die sich aus diesen Befunden ergebenden Konsequenzen für die zur Diskussion stehenden Vorstellungen über das Wesen der Genwirkungen werden besprochen.

Blitzlichtuntersuchungen an organischen Farbstoff-Photohalbleitern

Vorliegende Arbeit zeigt, daß das von Kepler und Le Blanc für Einkristalluntersudiungen ent­wickelte Impulsmeßverfahren, bei dem die durch einen Lichtblitz von etwa 1/2 Mikrosekunde Dauer ausgelöste Ladungsträgerwanderung oszillographisch registriert wird, auch für die Untersuchung von Farbstoff-Photoleitern geeignet ist.

Für undotierte und dotierte Farbstoffe verschiedener Klassen wurden mit dem Verfahren Drift­beweglichkeiten μ der Elektronen und Defektelektronen in der Größenordnung von 10-2 bis 1 [cm2/Vsec] bestimmt. Die an Phthalocyaninen gemessene Beweglichkeit μ > 1 [cm2/Vsec] und die bei Temperaturabnahme beobachtete Beweglichkeitszunahme bestätigten dabei die Anwendbar­keit des früher postulierten Energiebändermodells für die Beschreibung des Ladungsträgertrans­ports in Farbstoff-Photoleitern. Auch konnten ungelöste Probleme der organischen Halbleiter, wie die Frage der Ursache von n- und p-Leitung oder der Dotierung, mit Hilfe der Blitzlichtmethode einer Lösung nahegebracht werden.

Über die enzymatische Spaltung der Desoxyribosenucleinsäure aus Thymus und der Ribosenucleinsäure aus Hefe

Die Diffusionskonstanten verschiedener Purinderivate werden gemessen. Bei den Nucleotiden, insbesondere bei der Hefeadenylsäure, ergibt sich eine starke pH-Abhängigkeit der Diffusionskonstanten, die einer Änderung des Molgewichts um das 2,5-fache entsprechen würde. Bei der Spaltung der Ribosenucleinsäure aus Hefe mit kristallisierter Ribonuclease treten zu 82% dialysierbare Bruchstücke auf, deren durchschnittliche Diffusionskonstante in alkalischer Lösung mit der von Hefeadenylsäure übereinstimmt. Wegen des anomalen Verhaltens dieser Bezugssubstanz darf aber hieraus nicht geschlossen werden, daß die Spaltstücke die Größe von Mononucleotiden besitzen. Das Spaltgemisch konnte papierchromatographisch in vier einzelne Fraktionen aufgetrennt werden. Jede Fraktion ergibt bei der alkalischen Hydrolyse Adenylsäure und ein bis drei andere Nucleotide. Die Spaltstücke sind also wahrscheinlich Oligonucleotide vom Polymerisationsgrad 2—4. Bei der Spaltung der Thymonucleinsäure mit kristallisierter Desoxyribonuclease treten zu 90% dialysable Spaltstücke auf, die in ihrer Größe denen der Ribcsenucleinsäure entsprechen. Papierchromatographisch ließen sich hier keine definierten Fraktionen nachweisen.

Das Verhalten der alkalischen und sauren Phosphatase im Muskel der mit Coxsackie -Viren infizierten ausgewachsenen Maus

Nach Infektion mit Coxsackie-Virus A1 und A2 ist bei der ausgewachsenen Maus nach 48 bis 68 Stdn. als Zeichen einer inapparenten Infektion eine Steigerung der Aktivität der alkalischen Phosphatase und in geringerem Maße der sauren Phosphatase im Skelettmuskel zu beobachten. Nach Infektion mit dem Coxsackie-A3-Stamm bleibt die Aktivität der alkalischen Phosphatase unverändert, die saure Phosphatase ist signifikant erhöht.

Der Gehalt der Muskulatur an anorganischem Phosphat, gesamtsäurelöslichem Phosphat, Ribonucleinsäure und Desoxyribonucleinsäure verändert sich nach Infektion mit diesen Virusstämmen nicht.

Die Aktivität der Phosphatasen in der Aortenwand der Ratte nach Gonadektomie, Hypophysektomie, Adrenalektomie und bei experimenteller renaler Hypertonie

Die Aktivität der alkalischen Phosphatase (AP) in der Aortenwand der Ratte zeigt nach Gonadektomie bei Weibchen einen signifikanten Anstieg mit folgendem Absinken, während bei Männchen keine Aktivitätsänderung festzustellen ist.

Nach Hpophysektomie fällt die AP-Aktivität bei Männchen stark ab, während bei Weibdien eine derartige Aktivitätsverschiebung fehlt.

Adrenalektomie ist bei beiden Geschlechtern in der angewandten Versuchsanordnung wirkungslos.

Experimentelle renale Hypertonie führt bei Rattenmännchen zu einem signifikanten Aktivitätsanstieg von AP und saurer Phosphatase (SP) in der Aortenwand.

Es wird besprochen, welche Faktoren möglicherweise für die beobachteten Veränderungen der Phosphatase-Aktivität verantwortlich sind.

Membranes for biohybrid liver support: the behaviour of C3A hepatoblastoma cells is dependent on the composition of acrylonitrile copolymers

Co-polymers based on acrylonitrile, N-vinylpyrrolidone, aminoethylmethacrylate and sodium methallylsulfonate were used to prepare flat membranes by phase inversion. The surface properties of membranes were characterised by water contact angle measurements, atomic force microscopy and X-ray photoelectron spectroscopy (XPS). Membrane permeability was estimated by porosity measurements with water as test liquid. Human C3A hepatoblastoma cells were plated on these materials. Cell-material interaction was characterised by overall cell morphology, formation of focal adhesion contacts and intercellular junctions. Furthermore, cell proliferation was measured and compared with the functional activity of cells as indicated by 7-ethoxycoumarin-O-deethylation. More hydrophilic materials reduced spreading of cells, formation of focal adhesion and subsequent proliferation while homotypic cell adhesion was facilitated in correlation with stronger expressions of intercellular junctions and improved functional activity. In contrast, membranes with stronger adhesivity enhanced cell proliferation but reduced the functional activity of cells. It was concluded that the co-polymerisation of acrylonitrile with hydrophilic co-monomers, such as N-vinylpyrrolidone, could be used to tailor membrane materials for the application in biohybrid liver support systems.

On the tissue compatibility of poly(ether imide) membranes: an in vitro study on their interaction with human dermal fibroblasts and keratinocytes

Recently we have developed a novel type of membrane based on poly(ether imide) (PEI) which is considered for biomedical application. To improve its physical and biological performance it was modified by blending with poly(benzimidazole) (PBI). In the present study both membranes were characterized in terms of their physicochemical properties and in vitro tissue compatibility using human dermal fibroblasts and keratinocytes. The modified membrane (PEI*) was more hydrophilic, less porous and had an increased surface (zeta) potential. We further found that blending with PBI tends to promote cell contact, at least initially, as indicated by the improved overall cell morphology, adhesion and spreading of fibroblasts, and the development of focal adhesion complexes. The effects of fibronectin (FN) and serum coating were also beneficial when compared to pure PEI and tissue culture polystyrene (TCP), which correlates to a higher adsorption of both FN and vitronectin detected by ELISA. However, a clear tendency for homotypic cellular interaction particularly of keratinocytes was obtained in contact with membranes, which was much stronger pronounced on PEI*. Although the initial adhesion was greater on PEI*, a surprising decrease in cell growth was observed at later stages of incubation, which may be explained with the membrane-promoted cellular aggregation leading to an easier detachment from the substratum. Thus, membranes based on blends of PEI with PBI could provide a tissue compatible scaffold with lowered adhesive properties, which might be a useful tool for the transfer of cells, for example, to in vitro engineered tissue constructs.

[EAU guidelines on testicular cancer: 2011 update. European Association of Urology]

CONTEXT

On behalf of the European Association of Urology (EAU), guidelines for the diagnosis, therapy, and follow-up of testicular cancer were established.

OBJECTIVE

This article is a short version of the EAU testicular cancer guidelines and summarises the main conclusions from the guidelines on the management of testicular cancer.

EVIDENCE ACQUISITION

Guidelines were compiled by a multidisciplinary guidelines working group. A systematic review was carried out using Medline and Embase, also taking Cochrane evidence and data from the European Germ Cell Cancer Consensus Group into consideration. A panel of experts weighted the references, and a level of evidence and grade of recommendation were assigned.

RESULTS

There is a paucity of literature especially regarding longer term follow-up, and results from a number of ongoing trials are awaited. The choice of treatment centre is of the utmost importance, and treatment in reference centres within clinical trials, especially for poor-prognosis nonseminomatous germ cell tumours, provides better outcomes. For patients with clinical stage I seminoma, based on recently published data on long-term toxicity, adjuvant radiotherapy is no longer recommended as first-line adjuvant treatment. The TNM classification 2009 is recommended.

CONCLUSIONS

These guidelines contain information for the standardised management of patients with testicular cancer based on the latest scientific insights. Cure rates are generally excellent, but because testicular cancer mainly affects men in their third or fourth decade of life, treatment effects on fertility require careful counselling of patients, and treatment must be tailored taking individual circumstances and patient preferences into account.

TAKE HOME MESSAGE

Although testicular cancer has excellent cure rates, the choice of treatment centre is of the utmost importance. Expert centres achieve better results for both early stage testicular cancer (lower relapse rates) and overall survival (higher stages within clinical trials). For patients with clinical stage I seminoma, adjuvant radiotherapy is no longer recommended as first-line adjuvant treatment.

Chiral sulfoxides as metabolites of 2-thioimidazole-based p38α mitogen-activated protein kinase inhibitors: enantioselective synthesis and biological evaluation

A number of pharmaceutically important drugs contain asymmetric sulfinyl moieties, so the biological evaluation of chiral sulfoxides as human drug metabolites is important for the development of safe and effective pharmaceuticals. Asymmetric oxidation is one of the most attractive ways to prepare chiral sulfoxides. In combination with different chiral ligands, the iron- and titanium-catalyzed asymmetric oxidations of tri- and tetrasubstituted 2-thioimidazoles afford the corresponding sulfoxides with enantiomeric excesses up to 99% as novel p38α mitogen-activated protein kinase (p38α MAPK) inhibitors. The enantiomerically pure sulfoxides were evaluated on their inhibitory potency against p38α MAPK compared to the respective sulfides and sulfoxide racemates and showed differences in their affinities for the enzyme with IC(50) in the low nanomolar range. In addition, the ability to inhibit the release of tumor necrosis factor-α (TNF-α) from human whole blood (HWB) was examined. Some pyridinylimidazole derivatives showed excellent HWB activity with IC(50) as low as 52 nM.

N-(4-Chloro-pyridin-2-yl)-N-(4-methyl-phenyl-sulfon-yl)acetamide

The crystal structure of the title compound, C(14)H(13)ClN(2)O(3)S, features a three-dimensional network stabilized by inter-molecular C-H⋯O hydrogen bonds between the mol-ecules. The 4-methyl-phenyl-sulfonyl ring forms a dihedral angle of 30.6 (1)° with the 4-chloro-pyridine ring.

Differential effects of p38MAP kinase inhibitors on the expression of inflammation-associated genes in primary, interleukin-1beta-stimulated human chondrocytes

BACKGROUND AND PURPOSE

A main challenge in the therapy of osteoarthritis (OA) is the development of drugs that will modify the disease. Reliable test systems are necessary to enable an efficient screening of therapeutic substances. We therefore established a chondrocyte-based in vitro cell culture model in order to characterize different p38MAPK inhibitors.

EXPERIMENTAL APPROACH

Interleukin-1beta (IL-1beta)-stimulated human OA chondrocytes were treated with the p38MAPK inhibitors Birb 796, pamapimod, SB203580 and the new substance CBS-3868. Birb 796- and SB203580-treated cells were analysed in a genome-wide microarray analysis. The efficacy of all inhibitors was characterized by quantitative gene expression analysis and the quantification of PGE(2) and NO release.

KEY RESULTS

Microarray analysis revealed inhibitor-specific differences in gene expression. Whereas SB203580 had a broad effect on chondrocytes, Birb 796 counteracted the IL-1beta effect more specifically. All p38MAPK inhibitors significantly inhibited the IL-1beta-induced gene expression of COX-2, mPGES1, iNOS, matrix metalloproteinase 13 (MMP13) and TNFRSF11B, as well as PGE(2) release. Birb 796 and CBS-3868 showed a higher efficacy than SB203580 and pamapimod at inhibiting the expression of COX-2 and MMP13 genes, as well as PGE(2) release. In the case of mPGES1 and TNFRSF11B gene expression, CBS-3868 exceeded the efficacy of Birb 796.

CONCLUSIONS AND IMPLICATIONS

Our test system could differentially characterize inhibitors of the same primary pharmaceutical target. It reflects processes relevant in OA and is based on chondrocytes that are mainly responsible for cartilage degradation. It therefore represents a valuable tool for drug screening in between functional in vitro testing and in vivo models.

Tri- and tetrasubstituted imidazoles as p38α mitogen-activated protein kinase inhibitors

The synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles as potent p38α mitogen-activated protein kinase inhibitors is described. The trisubstituted imidazole series was found to be more potent than the tetrasubstituted imidazole series. Many of these compounds show low-nanomolar activities in the isolated p38α MAP kinase inhibition assay. The structure-activity relationships between these two series are different and not comparable.

2-(Bicyclo[2.2.1]hept-5-en-2-yl)-1H-pyrrolo[2,3-b]pyridine

The crystal structure of the title compound, C₁₄H₁₄N₂, displays inter­molecular N—H⋯N hydrogen bonds, forming dimers of enanti­omeric mol­ecules via a crystallographic centre of inversion.

2-(4-Fluoro-phen-yl)-N-{4-[6-(4-fluoro-phen-yl)-2,3-dihydro-imidazo[2,1-b][1,3]thia-zol-5-yl]pyridin-2-yl}acetamide

In the crystal structure of the title compound, C₂₄H₁₈F₂N₄OS, the imidazole system makes dihedral angles of 34.3 (1) and 43.9 (1)°, respectively, with the directly attached 4-fluoro­phenyl and pyridine rings. The crystal structure is stabilized by inter­molecular N—H⋯N hydrogen bonding and by an intra­molecular C—H⋯O hydrogen inter­action. The F atom of the 2-(4-fluoro­phen­yl) group is disordered over two positions with site-occupancy factors of 0.75 and 0.25.

7-[4-(4-Fluorophenyl)-2-methylsulfanyl-1H-imidazol-5-yl]tetrazolo[1,5-a]pyridine

The crystal structure of the title compound, C₁₅H₁₁FN₆S, forms a three-dimensional network stabilized by π–π inter­actions between the imidazole core and the tetra­zole ring of the tetra­zolopyridine­unit; the centroid–centroid distance is 3.627 (1) Å. The crystal structure also displays bifurcated N—H⋯(N,N) hydrogen bonding and C—H⋯F inter­actions. The former involve the NH H atom of the imidazole core and the tetra­zolopyridine N atoms, while the latter involve a methyl H atom, of the methyl­sulfanyl group, and the 4-fluoro­phenyl F atom. In the mol­ecule, the imidazole ring makes dihedral angles of 40.45 (9) and 17.09 (8)°, respectively, with the 4-fluoro­phenyl ring and the tetra­zolopyridine ring mean plane.

2-Acylaminopyridin-4-ylimidazoles as p38 MAP kinase inhibitors: Design, synthesis, and biological and metabolic evaluations

Targeting cytokines has become an important focus in the treatment of many inflammatory disorders. p38 MAP kinase (MAPK) is the key enzyme in regulating the biosynthesis and release of pro-inflammatory cytokines such as IL-1beta and TNFalpha. Inhibition of p38 MAPK results in decreased expression of these cytokines. Tri- and tetrasubstituted pyridinylimidazoles are potent inhibitors of p38 MAPK. Substitution on the pyridinyl moiety allows the design of inhibitors that show increased selectivity and activity by targeting the enzyme's hydrophobic region II. The objective of this study was to synthesize novel 1,2,4,5-tetrasubstituted imidazole derivates and to characterize them not only for their ability to inhibit p38 MAPK and modulate cytokine release in human whole blood, but also to evaluate their metabolic stability. Biological data and metabolic studies demonstrate that the introduction of a 2-acylamino function at C2 of the pyridine results in highly efficient and metabolically stable inhibitors relative to C2-alkylamino derivatives. A series of novel candidates was investigated for metabolic stability in human liver microsomes and in human whole blood. Additionally, metabolic S-oxidation was investigated, and possible metabolites were synthesized.

2-(3,4,5-Trimethoxyphenyl)-1H-pyrrolo[2,3-b]pyridine

In the title compound, C₁₆H₁₆N₂O₃, the 3,4,5-trimethoxy­phenyl group makes a dihedral angle of 10.04 (7)° toward the 1H-pyrrolo[2,3-b]pyridine system. The crystal structure displays inter­molecular N—H⋯N hydrogen bonds, forming inversion dimers.

4-Chloro-1-(4-methylphenylsulfonyl)-1H-pyrrolo[2,3-b]pyridine

The crystal structure of the title compound, C₁₄H₁₁ClN₂O₂S, features a three-dimensional network stabilized by π–π inter­actions between the rings of the 4-methyl­phenyl­sulfonyl protecting group [centroid–centroid distance = 3.623 (1) Å]. The 4-methyl­phenyl­sulfonyl ring makes a dihedral angle of 79.60 (6)° with the 4-chloro-1H-pyrrolo[2,3-b]pyridine unit.

N-{4-[4-(4-Fluoro-phen-yl)-1-methyl-2-[(R)-methyl-sulfin-yl]-1H-imidazol-5-yl]-2-pyridyl}acetamide dihydrate

In the crystal structure of the title compound, C(18)H(17)FN(4)O(2)S·2H(2)O, the organic mol-ecules are linked by inter-molecular O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonds with the water mol-ecules, generating a three-dimensional network. The imidazole ring system forms a dihedral angle of 24.9 (2)° with the 4-fluoro-phenyl ring. The pyridine ring is oriented approximately perpendicular [72.24 (8)°] to the imidazole ring system.

(2Z)-2-Fluoro-N-{4-[5-(4-fluoro-phen-yl)-2-methyl-sulfanyl-1H-imidazol-4-yl]-2-pyrid-yl}-3-phenyl-acrylamide

The asymmetric unit of the title compound, C₂₄H₁₈F₂N₄OS, contains two crystallographically independent mol­ecules, A and B, which are linked into two chains of A and B mol­ecules by inter­molecular N—H⋯O hydrogen bonds. The three-dimensional network is stabilized by π–π inter­actions between the pyridine rings and phenyl rings of different residues, with centroid–centroid distances of 3.793 (1) and 3.666 (2) Å. The mol­ecular conformation is stabilized by intra­molecular N—H⋯F hydrogen bonds (2.15/2.15Å). The imidazole rings make dihedral angles of 39.5 (2)/38.5 (2) and 31.8 (2)/33.2 (2)° with the 4-fluoro­phenyl rings and the pyridine rings, respectively. The methyl group of molecule A is disorderd in a 0.60:0.40 ratio.