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The atypical hemolytic-uremic syndrome (aHUS) belongs to the thrombotic mictroangiopathies (TMA). This group of diseases has traditionally been divided on clinical grounds by affected organs into thrombotic-thrombocytopenic purpura (TTP) and hemolytic-uremic syndrome (HUS), the latter being termed atypical if not preceeded by diarrhea. Tremendous scientific advances of the last two decases have shown that these clinically overlaping syndromes are caused by distinct molecular mechanisms. The definition of clinical syndromes has therefore been replaced by a TMA-classification on a molecular-mechanistic basis. aHUS is caused by an uncontrolled activation of the alternative complement pathway mostly due to genetic defects. These insights and particularly the development of a specific terminal complement inhibitor have revolutionized the treatment of aHUS and considerably improved its prognosis.

Due to advanced imaging techniques, renal cell carcinoma (RCC) is now identified earlier, often in localized stages. As a result, nephron-sparing surgical resection is possible in most cases. The development of new targeted therapies has changed the way metastatic RCC is treated. Despite this positive trend with improved survival rates and expanding treatment options, reliable biomarkers for better predicting disease course are lacking. These are urgently needed to enable personalized therapy based on the treatment-associated risks, the presence of comorbidities, and molecular tumor characteristics. We were able to show that proteins with a regulatory influence on apoptotic signal cascades represent not only promising prognostic markers, but also interesting targets for new therapeutic approaches. Furthermore, our data demonstrate that molecular tests are necessary to correctly classify a RCC with Xp11.2 translocation, since in addition to translocation, amplification can also result in TFE3 activation. Translational research with RCC biomarker identification and establishment, as well as molecular characterization and subtyping of RCCs is required to guide therapeutic decisions and enable personalized medicine in RCC patients.

In inhalation therapy, drugs are deposited as aerosols onto the air-facing lung epithelium. The currently used in vitro cell assays for drug testing, however, typically dissolve drugs in the medium, completely covering the cells, which represents an unphysiological drug application scenario. Although physiologically realistic in vitro cell culture models of the pulmonary air-blood barrier are available, reliable, easy-to-handle, and efficient technologies for direct aerosol-to-cell delivery are lacking. Here, we introduce the Air-Liquid Interface (ALI) Cell Exposure-Cloud (ALICE-CLOUD) technology, which uses principles of cloud motion for fast and quantitative delivery of aerosolized liquid drugs to pulmonary cells cultured under realistic ALI conditions. Aerosol-to-cell delivery proved to be highly efficient, reproducible, and rapid when using aerosolized fluorescein as surrogate drug. As a proof-of-concept study for the ALICE-CLOUD, we performed functional efficacy studies with the U.S. Food and Drug Administration-approved proteasome inhibitor, Bortezomib, a novel candidate drug for inhalation therapy. Aerosolized Bortezomib had a pronounced anti-inflammatory effect on human epithelial lung cells (A549), as indicated by a significant reduction of (TNFα-induced) IL-8 promoter activation. Importantly, cell-based therapeutic efficacy of aerosolized Bortezomib under ALI conditions was similar to that under dissolved and nonaerosolized submerged conditions, but with faster uptake kinetics. Our data indicate that the ALICE-CLOUD is a reliable tool for aerosolized drug screening with cells cultured under ALI conditions, which combines ease of handling with rapid, efficient, and dosimetrically accurate drug-to-cell delivery. This may pave the way for screening of inhalable drugs under physiologically more relevant and, hence, potentially more predictive conditions than the currently used submerged cell culture systems.

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors in the digestive tract. In up to 90% of cases, they are characterized by activating mutations in the KIT or the PDGFRA gene. GIST represent a paradigm for successful targeted treatment with tyrosine kinase inhibitors (TKI). Since the approval of the TKI imatinib in 2002 the survival of patients with metastatic GIST has tripled. The next logical step was the concept of using imatinib in an adjuvant approach, which was recently shown to increase overall survival significantly. In both settings, the mutational status has high predictive implications. In detail, GIST with KIT exon 11 mutations show the best response rates with partial remission rates of up to 80%. In KIT exon 9 mutations, a doubled daily dose of 800 mg imatinib is now standard. The PDGFRA exon 18 mutation D842V has been shown to lead to primary resistance. The treatment strategy in GIST is driven by their molecular characterisation. Further research has increased our knowledge on resistance mechanisms in solid tumors against TKI. The number of patients with secondary resistance due to acquired KIT mutations is increasing with treatment duration. Strategies to address this situation are the introduction of novel pathway inhibitors targeting different levels of signal transduction pathways, such as the mTOR/Akt pathway, the RAS/RAF pathway, histone deacetylation, among others. Among the GIST without mutations in the common hot spot regions of KIT and PDGFRA, the so-called wildtype GIST, further genomic subgroups have been identified. One such subgroup carries inactivating germline mutations in the genes encoding succinate dehydrogenase B, C, or D. They are associated with the occurrence of paragangliomas, so-called Carney-Stratakis syndrome. Most frequently, these GIST are located in the stomach, showing an epithelioid phenotype and a multinodular growth pattern. They preferentially occur in young females and often show lymph node metastases, the latter being very unusual in sporadic GIST. In sporadic Carney's triad additional pulmonary chondromas are observed and there are no SDH mutations. Another small subgroup of sporadic GIST present with BRAF mutations as an alternative genomic event. Finally, very rare kindreds with germline mutations in either KIT or PDGFRA have been described who develop multiple GIST and depending on the mutational subtype mastocytosis, hyperpigmentation and/or dysphagia. In summary, the molecular characterisation of GIST has revolutionized their treatment due to increasing knowledge about the high relevance of predictive molecular typing in solid tumors.

The primary open-angle glaucoma (POAG) is an optic neuropathy which is influenced by a number of different risk factors. Some of them can induce the transcriptional factor NF-kappaB, a nuclear protein which binds to specific areas of the DNA to stimulate different genes. NF-kappaB can be activated by increased intraocular pressure, increased age, vascular diseases and by oxidative stress. In the case of POAG NF-kappaB might be overstimulated with the induction of uncontrolled biochemical reactions. Treatment strategies for reducing NF-kappaB are to reduce intraocular pressure as well as therapies with statins, omega-3-fatty acids and alpha-lipoic acid. This model is a hypothesis and is intended to provide a basis for further discussions and basic research.

Nuclear receptors are ligand-dependent transcription factors, that regulate the expression of hormone inducible genes. I investigated the influence of different ecdysone response elements (EcREs) on the stability and transcriptional activity of the ecdysteroid receptor. The ecdysteroid receptor is the phylogenetically oldest steroid receptor and is formed by the ecdysone receptor (EcR) and ultraspiracle (Usp). The EcR / Usp heterodimer is distinguished as the functional ecdysteroid receptor, but EcR and Usp are also functional on their own. DNA-binding of the ecdysteroid receptor regulates not only its transcriptional activity, but also its protein concentration. Proteosomal degradation of the ecdysteroid receptor is possible, because degradation sequences - like ubiquitination sites or PEST sequences - are present in EcR and Usp. The transcriptional activity of the ecdysteroid receptor depends on the kind and number of the EcRE and is modulated by the A/B domains of EcR and Usp, as well as the DNA-binding domain (DBD) of Usp. Ecdysone response elements are one possibility how the homo- and heterodimers of the ecdysteroid receptor are able to regulate different procedures in the animal.

There is increasing evidence that nitric oxide (NO), which was first identified as a unique diffusible molecular messenger in animals, plays an important role in diverse physiological processes in plants. Recent progress that has deepened our understanding of NO signalling functions in plants, with special emphasis on defence signalling, is discussed here. Several studies, based on plants with altered NO-levels, have recently provided genetic evidence for the importance of NO in gene induction. For a general overview of which gene expression levels are altered by NO, two studies, involving large-scale transcriptional analyses of Arabidopsis thaliana using custom-made or commercial DNA-microarrays, were performed. Furthermore, a comprehensive transcript profiling by cDNA-amplification fragment length polymorphism (AFLP) revealed a number of Arabidopsis thaliana genes that are involved in signal transduction, disease resistance and stress response, photosynthesis, cellular transport, and basic metabolism. In addition, NO affects the expression of numerous genes in other plant species such as tobacco or soybean. The NO-dependent intracellular signalling pathway(s) that lead to the activation or suppression of these genes have not yet been defined. Several lines of evidence point to an interrelationship between NO and salicylic acid (SA) in plant defence. Recent evidence suggests that NO also plays a role in the wounding/jasmonic acid (JA) signalling pathway. NO donors affect both wounding-induced H2O2 synthesis and wounding- or JA-induced expression of defence genes. One of the major challenges ahead is to determine how the correct specific response is evoked, despite shared use of the NO signal and, in some cases, its downstream second messengers.

Skeletal muscle shows a unique ability to adapt its structure and function to various stimuli. The recent use of molecular-biological technology indicates that in human skeletal muscle exercise stimuli cause a rapid increase in the transcription of DNA sequences for metabolic and regulatory genes into messenger RNA. Additionally, repetitive and systematic exercise stimuli cause a change in the concentration of certain mitochondrial and contractile RNAs. These distinct changes in gene expression reflect the specific adaptations of the mitochondrial and myofibrillar structure of skeletal muscle to different stimuli as endurance exercise, strength training, and immobilization, respectively. Multiple molecular sensors have been identified which are involved in the sensation, transmission and integration of mechanical, metabolic, hormonal and neuronal signals of the more complex stimuli of exercise training into the observed adaptations of gene expression. The data support the fundamental concept, that by instructing the synthesis of encoded protein(s) changes in gene expression are responsible for the microadaptations of regularly exercised human skeletal muscles leading towards a new training steady-state.

Comparative studies were conducted through more than six months into quantitative of bovine leukaemia virus (BLV) antigen of FLC/BLV 44 and its FLC/BLV 44-4 subline by means of an enzyme immuno-assay (EIA), using monoclonal antibodies against gp51 and p24. Synthesis of gp51 (factors of two to six) and of p24 (factor of two) by FLC/BLV 44 was clearly higher than that by FLC/BLV 44-4. The transactivation status in either line was determined by transfer of the beta-galactosidase indicator organ under transcription control of BLV-LTR (in pBLV beta Gal plasmid). Transient experiments showed beta-galactosidase activity in the FLC/BLV 44 to be clearly higher than that in subline FLC/BLV 44-4. There is obviously in both cell lines a close correlation between intensity of BLV antigen synthesis and transactivation processes.

The mouse mammary tumor virus (MMTY) long terminal repeat (LTR) open reading frame (ORF) encodes a nagative acting factor (naf). In our test system, naf mediates its effect in trans on another MMTV provirus in which the 5′ LTM has been replaced by that of Rous sarcoma virus. naf effects are evidenced at the evidenced at the level of transcriptional initiation rather than as reduced mRNA stability. The introduction of a premature termination codon into the MMTV LTR-encoded ORF abolishes the transcriptional down regulation localizing naf within the ORF. In addition, sequences in the gag/pol genes between + 320 and + 646 and between + 3626 and + 4590 relative to the site of transcription initiation are also involved in the MMTV- mediated transcriptional down regulation.