A large and diverse brain organoid dataset of 1,400 cross-laboratory images of 64 trackable brain organoids.

Brain organoids represent a useful tool for modeling of neurodevelopmental disorders and can recapitulate brain volume alterations such as microcephaly. To monitor organoid growth, brightfield microscopy images are frequently used and evaluated manually which is time-consuming and prone to observer-bias. Recent software applications for organoid evaluation address this issue using classical or AI-based methods. These pipelines have distinct strengths and weaknesses that are not evident to external observers. We provide a dataset of more than 1,400 images of 64 trackable brain organoids from four clones differentiated from healthy and diseased patients. This dataset is especially powerful to test and compare organoid analysis pipelines because of (1) trackable organoids (2) frequent imaging during development (3) clone diversity (4) distinct clone development (5) cross sample imaging by two different labs (6) common imaging distractors, and (6) pixel-level ground truth organoid annotations. Therefore, this dataset allows to perform differentiated analyses to delineate strengths, weaknesses, and generalizability of automated organoid analysis pipelines as well as analysis of clone diversity and similarity.

Tyrosine hydroxylase variants influence protein expression, cellular localization, stability, enzymatic activity and the physical interaction between tyrosine hydroxylase and GTP cyclohydrolase 1.

Tyrosine hydroxylase (TH) is the rate-limiting enzyme in dopamine biosynthesis catalyzing the tetrahydrobiopterin (BH4 )-dependent hydroxylation of tyrosine to L-DOPA. Here, we analyzed 25 TH variants associated with various degrees of dopa-responsive dystonia and evaluate the effect of each variant on protein stability, activity and cellular localization. Furthermore, we investigated the physical interaction between TH and human wildtype (wt) GTP cyclohydrolase 1 (GTPCH) and the effect of variants on this interaction. Our in vitro results classify variants according to their resistance to proteinase K digestion into three groups (stable, intermediate, unstable). Based on their cellular localization, two groups of variants can be identified, variant group one with cytoplasmic distribution and variant group two forming aggregates. These aggregates do not correlate with loss of enzymatic activity but nevertheless might be a good target for molecular chaperones. Unfortunately, no obvious correlation between the half-life of a variant and its enzymatic activity or between solubility, stability and enzymatic activity of a given variant could be found. Excitingly, some variants disrupt the physical interaction between TH and human wildtype GTPCH, thereby interfering with enzymatic activity and offering new druggable targets for therapy. Taken together, our results highlight the importance of an in-depth molecular analysis of each variant in order to be able to classify groups of disease variants and to find specific therapies for each subgroup. Stand-alone in silico analyses predict less precise the effect of specific variants and should be combined with other in vitro analyses in cellular model systems.

Intradermal testing and serum allergen-specific IgE-testing in cats with naturally occurring feline bronchial disease.

OBJECTIVES: While feline asthma (FA) is considered to be of allergic origin, the etiology of feline chronic bronchitis (CB) to date is unknown. Aim of the study was to compare the results of intradermal testing (IDT) and serum testing for allergen-specific immunoglobulin E (SAT) in cats diagnosed with FA and CB. MATERIAL AND METHODS: Twenty-seven client-owned cats with clinical signs, suggestive of feline inflammatory bronchial disease (FBD) were prospectively enrolled in the study. Patients were assigned to 3 groups based on results of bronchoalveolar-lavage-fluid (BALF)-cytology: FA (n=8), CB (n=10), or cats with a physiological BALF cytology (PB; n=9). A standardized IDT for 27 allergens was performed in all cats. In addition, allergen-specific IgE was measured in serum samples using an FcεRIα-ELISA. The number of positive reactions in both tests was compared between groups, and agreement between test results of both tests was evaluated. RESULTS: Regarding the number of positive reactions, no statistically significant difference was detected between groups in IDT (p=0.65) and SAT (p=0.51). When comparing the 2 test systems, a weak correlation was found for the allergens Tyrophagus putrescentiae (k=0.256), Dermatophagoides farinae (k=0.276), and rye (k=0.273). The most commonly observed reactions were to house dust mites, storage mites, rye and nettle in IDT and to sheep sorrel, storage mites, and house dust mites in SAT. CONCLUSION AND RELEVANCE: IDT and SAT in cats with feline inflammatory bronchial disease (FBD) cannot be used interchangeably for allergen detection. Sensitization to environmental allergens can occur in cats with and without airway inflammation. Therefore, a positive test result should always be assessed in context with clinical signs and allergen exposure.

An AI-based segmentation and analysis pipeline for high-field MR monitoring of cerebral organoids.

Cerebral organoids recapitulate the structure and function of the developing human brain in vitro, offering a large potential for personalized therapeutic strategies. The enormous growth of this research area over the past decade with its capability for clinical translation makes a non-invasive, automated analysis pipeline of organoids highly desirable. This work presents a novel non-invasive approach to monitor and analyze cerebral organoids over time using high-field magnetic resonance imaging and state-of-the-art tools for automated image analysis. Three specific objectives are addressed, (I) organoid segmentation to investigate organoid development over time, (II) global cysticity classification and (III) local cyst segmentation for organoid quality assessment. We show that organoid growth can be monitored reliably over time and cystic and non-cystic organoids can be separated with high accuracy, with on par or better performance compared to state-of-the-art tools applied to brightfield imaging. Local cyst segmentation is feasible but could be further improved in the future. Overall, these results highlight the potential of the pipeline for clinical application to larger-scale comparative organoid analysis.

Immunoadsorption in a dog with severe immune mediated hemolytic anemia.

Immune mediated hemolytic anemia (IMHA) is a life-threatening disease with severe, acute hemolysis as a result of an autoimmune response directed against erythrocyte surface antigens. In veterinary medicine, IMHA is usually treated with immunosuppressants and often multiple blood transfusions. In human medicine, immunoadsorption (IA) is an established therapy for antibody removal in immune-mediated diseases. A female, spayed, five-year-old, 28 kg Entlebucher Mountain dog was presented with regenerative anemia and positive autoagglutination diagnosed as immune-mediated hemolytic anemia to the veterinary emergency service. Conventional treatment consisting immunosuppression with prednisolone and mycophenolate failed to improve hemolysis. As hematocrit dropped daily, multiple blood transfusions of blood group DEA 1 negative were required. IA was initiated at day 3 with COM.TEC and ADAsorb platforms and a LIGASORBstaphylococcus antitoxin A column. IA with citrate anticoagulation was performed over the treatment time of 77 minutes with a blood flow of 50 mL/min. Total plasma volume of 1.6 L was processed. Complications consisted of vomitus and lid swelling, shivering, excessive clotting in the tubing after a calcium bolus and hypotension. After IA, hemolysis stopped immediately, plasma concentrations of immunoglobulin G, immunoglobulin M and bilirubin decreased, and hematocrit remained stable. The dog was discharged without further hemolysis 4 days after immunoadsorption with immunosuppressive therapy. IA is a promising adjunctive therapy in severe cases of canine IMHA, but it cannot be concluded to which degree IA or concurrent immunosuppression contributed to cessation of hemolysis in the present case.

Improvement of in vitro potency assays by a resting step for clinical-grade chimeric antigen receptor engineered T cells.

BACKGROUND: Chimeric antigen receptor engineered T (CAR-T) cell therapy is a promising approach currently revolutionizing the field of cancer immunotherapy. However, data concerning clinical-grade CAR-T cell stability and functionality after months of cryopreservation have not been released by companies so far. To investigate the effect of cryopreservation on CAR-T cells and to further optimize the potency assays, we performed this study. METHODS: A third generation of CD19 CAR-T cells was manufactured according to Good Manufacturing Practice (GMP) requirements, which is applied to patients in an ongoing clinical phase 1 study. Quality control tests for sterility, endotoxin and mycoplasma were performed for each batch. Stability in terms of viability, recovery, transduction efficiency and functional capacity was determined using microscopy, multiparametric flow cytometry as well as chromium-51 release tests. RESULTS: Up to 90days of cryopreservation had no influence on viability, recovery and transduction efficiency of CAR-T cells. However, higher cell concentration for cryopreservation could alter the cell viability and recovery but not the transduction efficiency. Moreover, directly after thawing, both the quantity and quality of the functionality of CAR-T cells were transiently hampered by the negative effects of cryopreservation. Notably, the impaired functionality could be fully restored and even strengthened after an overnight resting process. DISCUSSION: Cryopreservation is a challenge for the functional activity of CAR-T cells. However, CAR-T cells regain their potency by overnight incubation at 37°C, which mimics the clinical application setting. Therefore, an overnight resting step should be included in in vitro potency assays.

Cardiopulmonary response during whole-body vibration training in patients with severe COPD.

Several studies in patients with chronic obstructive pulmonary disease (COPD) have shown that whole-body vibration training (WBVT) has beneficial effects on exercise capacity. However, the acute cardiopulmonary demand during WBVT remains unknown and was therefore investigated in this study. Ten patients with severe COPD (forced expiratory volume in 1 s: 38±8% predicted) were examined on two consecutive days. On day one, symptom-limited cardiopulmonary exercise testing was performed on a cycle ergometer. The next day, six bouts of repeated squat exercises were performed in random order for one, two or three minutes either with or without WBVT while metabolic demands were simultaneously measured. Squat exercises with or without WBVT induced comparable ventilatory efficiency (minute ventilation (VE)/carbon dioxide production (V'CO2 ): 38.0±4.4 with WBVT versus 37.4±4.1 without, p=0.236). Oxygen uptake after 3 min of squat exercises increased from 339±40 mL·min-1 to 1060±160 mL·min-1 with WBVT and 988±124 mL min-1 without WBV (p=0.093). However, there were no significant differences between squat exercises with and without WBVT in oxygen saturation (90±4% versus 90±4%, p=0.068), heart rate (109±13 bpm versus 110±15 bpm, p=0.513) or dyspnoea (Borg scale 5±2 versus 5±2, p=0.279). Combining squat exercises with WBVT induced a similar cardiopulmonary response in patients with severe COPD compared to squat exercises without WBVT. Bearing in mind the small sample size, WBVT might be a feasible and safe exercise modality even in patients with severe COPD.

Myofibroblasts have an impact on expression, dimerization and signaling of different ErbB receptors in OSCC cells.

INTRODUCTION: Receptors of the ErbB family belong to the key players in cancer development and are targets of several therapeutic approaches. Their functional dependency on the tumor microenvironment, especially on CAFs is albeit still poorly understood. Our objective was to investigate the impact of CAF secretome on ErbB receptor expression and signaling behavior in OSCC. METHODS: Stimulation of PE/CA-PJ15 OSCC cells with conditioned media of TGF-ß1-activated fibroblasts was used as model system for CAF to cancer cell communication. Thereby costimulation with inhibitors against matrix metalloproteinases (MMPs), epidermal growth factor receptor (EGFR), MAPK/ERK kinase (MEK), phosphoinositide-3 kinase (PI3-K), signal transducer and activator of transcription 3 (Stat3) or knockdown of Her3 by siRNA was utilized for detailed investigation of the expression, dimerization and signaling pattern of ErbB in western blot and coimmunoprecipitation. RESULTS: Our results show that soluble factors in activated fibroblast secretome stimulate metalloproteinase activity in the membrane of cancer cells. Thereby ligands are released that activate EGFR and subsequently upregulates EGFR expression via the STAT3 pathway. Simultaneously, the expression of PKCɛ was enhanced via a PI3-kinase/Akt-mediated pathway and a negative feedback regulation loop on EGFR downstream signaling generated. Furthermore, the activated fibroblasts secretome stimulated the highly oncogenic hetero-dimerization between HER3 and p95HER2. That protein association is inversely dependent on the expression level of HER3. CONCLUSIONS: Our results demonstrate that the activated fibroblasts secretome can induce a counterbalanced regulation of protein expression, downstream signaling and the dimerization patterns of different ErbB receptor subtypes in the cancer cell. Thus, the combinatorial targeting of CAFs and selective ErbB receptor subtype inhibitors may provide a useful approach in cancer therapy.

Bevacizumab-Induced Inhibition of Angiogenesis Promotes a More Homogeneous Intratumoral Distribution of Paclitaxel, Improving the Antitumor Response.

The antitumor activity of angiogenesis inhibitors is reinforced in combination with chemotherapy. It is debated whether this potentiation is related to a better drug delivery to the tumor due to the antiangiogenic effects on tumor vessel phenotype and functionality. We addressed this question by combining bevacizumab with paclitaxel on A2780-1A9 ovarian carcinoma and HT-29 colon carcinoma transplanted ectopically in the subcutis of nude mice and on A2780-1A9 and IGROV1 ovarian carcinoma transplanted orthotopically in the bursa of the mouse ovary. Paclitaxel concentrations together with its distribution by MALDI mass spectrometry imaging (MALDI MSI) were measured to determine the drug in different areas of the tumor, which was immunostained to depict vessel morphology and tumor proliferation. Bevacizumab modified the vessel bed, assessed by CD31 staining and dynamic contrast enhanced MRI (DCE-MRI), and potentiated the antitumor activity of paclitaxel in all the models. Although tumor paclitaxel concentrations were lower after bevacizumab, the drug distributed more homogeneously, particularly in vascularized, non-necrotic areas, and was cleared more slowly than controls. This happened specifically in tumor tissue, as there was no change in paclitaxel pharmacokinetics or drug distribution in normal tissues. In addition, the drug concentration and distribution were not influenced by the site of tumor growth, as A2780-1A9 and IGROV1 growing in the ovary gave results similar to the tumor growing subcutaneously. We suggest that the changes in the tumor microenvironment architecture induced by bevacizumab, together with the better distribution of paclitaxel, may explain the significant antitumor potentiation by the combination.

Targeted delivery of interleukin-10 to chronic cardiac allograft rejection using a human antibody specific to the extra domain A of fibronectin.

BACKGROUND AND AIMS: Management of chronic rejection is challenging since there are not sufficient preventive or therapeutic strategies. The rejection process leads to overexpression of ED-A(+) fibronectin (ED-A(+) Fn). The human antibody F8, specific to ED-A(+) Fn, may serve as a vehicle for targeted delivery of bioactive payloads, e.g. interleukin 10 (IL-10). The aim of this study was to investigate the therapeutic effects of the fusion protein F8-interleukin-10 (F8-IL10) in the process of chronic rejection development. METHODS: A heterotopic rat heart transplantation model was used to induce chronic rejection. For therapeutic interventions, the immunocytokines F8-humanIL10 (DEKAVIL), F8-ratIL10 as well as KSF-humanIL10 (irrelevant antigen-specificity) were used. Treatment was performed weekly for 10 weeks starting at day 7 after transplantation (1mg/animal). RESULTS: In the cardiac allografts, treatment with F8-huIL10 or F8-ratIL10 was associated with increased heart weights, a higher grade of chronic rejection, increased CIF, higher protein expression levels of alpha-smooth muscle actin (α-SMA), an augmented infiltration with inflammatory cells (CD4+, CD8+ and CD68+ cells) and higher serum levels of brain natriuretic peptide (BNP) compared to the control groups. CONCLUSIONS: All observed treatment effects are transplantation-specific since the F8 antibody is specific to ED-A(+) Fn that is not expressed in healthy hearts. A clear targeting effect of F8-huIL10 as well as F8-ratIL10 could be proven. Against that background, a further study is needed to address the question, if F8-IL10 treatment is capable to reduce CAV and CIF starting at a time point when chronic rejection has fully developed (therapeutic approach).

Tenascin-C and carcinoma cell invasion in oral and urinary bladder cancer.

Carcinoma invasion is a complex process regulated by genetic and epigenetic factors as well. A relevant supportive condition for cancer cell migration is the reorganization of the extracellular matrix (ECM), which is realized in an orchestrated multicellular manner including carcinoma cells and stromal fibroblasts. An important key player in the process of ECM reorganization is Tenascin-C (Tn-C). The molecule occurs as different isoforms generated by alternative splicing and de novo glycosylation. Large variants of Tn-C are abundantly re-expressed in the invasive front of many carcinoma types. A special role for initiating migration and accompanied epithelial to mesenchymal transition has been suggested. Here, we review the current knowledge concerning the tumor biological importance of Tn-C, the synthesis and alternative splicing during the invasive process in general, and give an overview on the impact of Tn-C in urothelial carcinoma of the urinary bladder (UBC) and oral squamous cell carcinoma (OSCC).

De novo expression of fetal ED-A(+) fibronectin and B (+) tenascin-C splicing variants in human cardiac allografts: potential impact for targeted therapy of rejection.

Management of acute and especially chronic rejection after human cardiac transplantation is still challenging. Chronic rejection, represented by allograft vasculopathy (CAV) and cardiac interstitial fibrosis (CIF) is known to cause severe long-term complications. Rejection associated tissue-remodelling entails the reoccurrence of fetal variants of Fibronectin (Fn) and Tenascin-C (Tn-C), which are virtually absent in adult human organs. In a rat model, an extensive re-expression could be demonstrated for ED-A(+) Fn with spatial association to CAV and CIF. Thus, it is of great interest to investigate the cardiac tissue expression and distribution in human samples. From 48 heart transplanted patients, 64 tissue specimens derived from right ventricular biopsies were available. Histopathological analysis was performed according to the International Society for Heart and Lung Transplantation (ISHLT) guidelines for the detection of acute rejection. By immunohistochemistry, protein expression of ED-A(+) Fn, B(+) Tn-C, alpha-smooth muscle actin, CD31 and CD45 was assessed and analysed semiquantitatively. Co-localisation studies were performed by means of immunofluorescence double labelling. Histopathological analysis of the 64 samples revealed different ISHLT grades (0R in 36 cases, 1R in 20 cases and 2R in 8 cases). There was a distinct and quantitatively relevant re-occurrence of ED-A(+) Fn and B(+) Tn-C in most samples. Semi-quantitative evaluation did not show any correlation to the acute rejection grade for all markers. Interestingly, significant correlations to the extent of inflammation could be shown for ED-A(+) Fn (r = 0.442, p = 0.000) and B(+) Tn-C (r = 0.408, p = 0.001) as well as between both proteins (r = 0.663, p = 0.000). A spatial association of ED-A(+) Fn and B(+) Tn-C to CAV and CIF could be demonstrated. A relevant re-occurrence of ED-A(+) Fn and B(+) Tn-C following human heart transplantation could be demonstrated with spatial association to signs of rejection and a significant correlation to tissue inflammation. These data might contribute to the identification of novel biomarkers reflecting the rejection process and to the development of promising strategies to image, prevent or treat cardiac rejection.

Detection of feline Mycoplasma species in cats with feline asthma and chronic bronchitis.

Little is known about the aetiology of inflammatory lower airway disease in cats. The aim of this study was to investigate the role of Mycoplasma species in cats with feline asthma (FA) and chronic bronchitis (CB). The study population consisted of 17 cats with FA/CB, and 14 sick cats without clinical and historical signs of respiratory disease, which were euthanased for various other reasons. Nasal swabs, nasal lavage and bronchoalveolar lavage fluid (BALF) samples were taken from patients from both groups. Mycoplasma species culture with modified Hayflick agar and Mycoplasma polymerase chain reaction (PCR) were performed on all samples followed by sequencing of all Mycoplasma species-positive samples for differentiation of subspecies. PCR testing detected significantly more Mycoplasma species-positive BALF samples than Mycoplasma culture (P = 0.021). When cats with oropharyngeal contamination were excluded from comparison, the numbers of Mycoplasma species-positive BALF samples in the group with FA/CB (6/17) and the control group (4/9) were not significantly different (P = 0.6924). While all nasal samples of the cats with FA/CB were negative for Mycoplasma organisms, five samples in the control group (P = 0.041) were positive on PCR. Sequencing revealed Mycoplasma felis in all PCR-positive samples. Mycoplasma species can be detected in the lower airways of cats with FA/CB, as well as in the BALF of sick cats without respiratory signs. Further studies are warranted to investigate the possibility that Mycoplasma species represent commensals of the lower respiratory tract of cats.

Effects of activated fibroblasts on phenotype modulation, EGFR signalling and cell cycle regulation in OSCC cells.

Crosstalk between carcinoma associated fibroblasts (CAFs) and oral squamous cell carcinoma (OSCC) cells is suggested to mediate phenotype transition of cancer cells as a prerequisite for tumour progression, to predict patients' outcome, and to influence the efficacy of EGFR inhibitor therapies. Here we investigate the influence of activated fibroblasts as a model for CAFs on phenotype and EGFR signalling in OSCC cells in vitro. For this, immortalised hTERT-BJ1 fibroblasts were activated with TGFß1 and PDGFAB to generate a myofibroblast or proliferative phenotype, respectively. Conditioned media (FCMTGF, FCMPDGF) were used to stimulate PE/CA-PJ15 OSCC cells. Results were compared to the effect of conditioned media of non-stimulated fibroblasts (FCMB). FCMTGF stimulation leads to an up-regulation of vimentin in the OSCC cells and an enhancement of invasive behaviour, indicating EMT-like effects. Similarly, FCMTGF≫FCMPDGF induced up-regulation of EGFR, but not of ErbB2/ErbB3. In addition, we detected an increase in basal activities of ERK, PI3K/Akt and Stat3 (FCMTGF>FCMPDGF) accompanied by protein interaction of vimentin with pERK. These effects are correlated with an increased proliferation. In summary, our results suggest that the activated myofibroblast phenotype provides soluble factors which are able to induce EMT-like phenomena and to increase EGFR signalling as well as cell proliferation in OSCC cells. Our results indicate a possible influence of activated myofibroblasts on EGFR-inhibitor therapy. Therefore, CAFs may serve as promising novel targets for combined therapy strategies.

Selective imaging of chronic cardiac rejection using a human antibody specific to the alternatively spliced EDA domain of fibronectin.

BACKGROUND: Chronic cardiac rejection is intimately associated with cardiac allograft vasculopathy and fibrosis, both causing severe complications that cannot be reversed. Thus, there is an urgent need for early diagnosis and for development of therapeutic agents. Chronic rejection is accompanied by the dramatic upregulation of EDA(+) fibronectin (EDA(+) Fn), which is virtually undetectable in the normal healthy adult. METHODS: In this study, we evaluated the potential of the monoclonal antibody F8, specific to that molecule, to selectively accumulate in chronically rejected allografts. RESULTS: A syngeneic immunocompetent heterotopic rat heart transplantation model was used to induce chronic rejection within 70 days. The F8 antibody or an antibody of irrelevant specificity, labeled with the dye DY-682, was administered and near-infrared fluorescence (NIRF) imaging was performed. Targeting performance was assessed by macroscopic organ imaging and fluorescence microscopy. A selective accumulation of the F8 antibody (but not of the negative control antibody) was observed by NIRF imaging in cardiac allografts. The antibody localized to diseased blood vessels as well as to fibrotic regions, where the cognate antigen is abundantly expressed. CONCLUSIONS: This is the first example of antibody-mediated imaging of chronic cardiac rejection. The findings pave the way to immuno-positron emission tomography (immuno-PET) imaging of this clinical condition in patients using the human F8 antibody labeled with a suitable radionuclide (e.g., iodine-124). Furthermore, it would be conceivable to use the F8 antibody as a delivery vehicle to assess experimentally whether a bioactive payload (e.g., drug or cytokine) may be able to reduce disease progression.

The tyrosine kinase inhibitor E-3810 combined with paclitaxel inhibits the growth of advanced-stage triple-negative breast cancer xenografts.

E-3810 is a novel small molecule that inhibits VEGF receptor-1, -2, and -3 and fibroblast growth factor receptor-1 tyrosine kinases at nmol/L concentrations currently in phase clinical II. In preclinical studies, it had a broad spectrum of antitumor activity when used as monotherapy in a variety of human xenografts. We here investigated the activity of E-3810 combined with different cytotoxic agents in a MDA-MB-231 triple-negative breast cancer xenograft model. The molecule could be safely administered with 5-fluorouracil, cisplatin, and paclitaxel. The E-3810-paclitaxel combination showed a striking activity with complete, lasting tumor regressions; the antitumor activity of the combination was also confirmed in another triple-negative breast xenograft, MX-1. The activity was superior to that of the combinations paclitaxel+brivanib and paclitaxel+sunitinib. Pharmacokinetics studies suggest that the extra antitumor activity of the combination is not due to higher paclitaxel tumor levels, which in fact were lower in mice pretreated with all three kinase inhibitors, and the paclitaxel plasma levels excluded reduced drug availability. Pharmacodynamic studies showed that E-3810, brivanib, and sunitinib given as single agents or in combination with paclitaxel reduced the number of vessels, but did not modify vessel maturation. Reduced tumor collagen IV and increased plasma collagen IV, associated with increased matrix metalloproteinases (MMP), particularly host MMP-9, indicate a proteolytic remodeling of the extracellular matrix caused by E-3810 that in conjunction with the cytotoxic effect of paclitaxel on the tumor cells (caspase-3/7 activity) may contribute to the striking activity of their combination. These data support the therapeutic potential of combining E-3810 with conventional chemotherapy.

Expression of the E-cadherin repressors Snail, Slug and Zeb1 in urothelial carcinoma of the urinary bladder: relation to stromal fibroblast activation and invasive behaviour of carcinoma cells.

Epithelial-mesenchymal transition (EMT) is regulated by interaction of carcinoma and stromal cells and crucial for progression of urinary bladder carcinoma (UBC). Therefore, the influence of activated fibroblasts on the expression of E-cadherin repressors as well as EMT and invasion in UBC was investigated. A correlative analysis of the immunohistochemical expression of fibroblast (ASMA, S100A4, FAP, SDF1, PDGFRß) and EMT (Snail, Slug, Zeb1, E-cadherin) markers was performed on 49 UBC cases of different stages. The impact of distinguishable growth factor stimulated fibroblasts on invasion, EMT, and E-cadherin repressor expression was investigated in an invasion model. In situ, invasiveness was significantly correlated to the loss of membranous E-cadherin (E-cad_m) and increased Snail, Slug, Zeb1 in tumour cells, as well as to increased ASMA, S100A4, and PDGFRß in stromal cells. A significant correlation to nodal metastasis could be evidenced for the loss of E-Cad_m, and for an increase in S100A4 and PDGFRß. Comparison of stromal and EMT markers revealed significant correlations of ASMA to Snail and Slug; of S100A4 to the loss of E-cad_m and Zeb1; and of PDGFRß to the loss of E-Cad_m, Slug and Zeb1. In vitro, TGFß1 induced myofibroblasts were the strongest attractants, while aFGF or TGFß1/aFGF stimulated fibroblasts were the most potent EMT inductors. As shown here for the first time, distinct sub-populations of fibroblasts are to various extents associated with EMT and tumour progression in UBC. These relevant findings might be the basis for the identification of new diagnostic markers and therapeutic targets selectively affecting tumour supporting CAF effects.

Bone marrow biopsies of patients with hematopoietic and lymphoid disorders - epidemiology, chromosomal aberrations and molecular pathology.

Bone marrow biopsy of the iliac crest is the first and most important step in the diagnostics of hematopoietic disorders. The biopsies of the years 2006 and 2007 from the Institute of Pathology of the Jena University Hospital were retrospectively analyzed for clinicopathological parameters. In addition, the Mitelman database was retrieved for chromosomal aberrations. The analysis of 2820 reports from 1185 patients revealed that lymphomas, plasma cell myeloma and acute leukemia were most frequent. Males predominated in myeloproliferative neoplasms and lymphoma subtypes, particularly CLL, except for plasma cell myeloma and acute leukemia. A peak incidence was seen between 61 and 70 years of age with a varying pattern for single entities. The database search revealed that ALL, AML, CLL and CML were mainly diploid while Hodgkin lymphoma, mature B-cell lymphoma and multiple myeloma mostly carried hyperdiploid chromosome numbers. Numerical aberrations like chromosome 8 gains in hyperdiploid CML were prominent in specific subgroups. Molecular testing is exemplified in CML, plasma cell myeloma and hairy cell leukemia. The study highlights typical clinicopathological characteristics and new genetic findings in hematopoietic and lymphoid neoplasms with relevance for the new WHO classification and beyond. We hope that it may help in the differential diagnosis of bone marrow biopsies.

Stoichiometry of the CD95 death-inducing signaling complex: experimental and modeling evidence for a death effector domain chain model.

The CD95 (Fas/APO-1) death-inducing signaling complex (DISC) is essential for the initiation of CD95-mediated apoptotic and nonapoptotic responses. The CD95 DISC comprises CD95, FADD, procaspase-8, procaspase-10, and c-FLIP proteins. Procaspase-8 and procaspase-10 are activated at the DISC, leading to the formation of active caspases and apoptosis initiation. In this study we analyzed the stoichiometry of the CD95 DISC. Using quantitative western blots, mass spectrometry, and mathematical modeling, we reveal that the amount of DED proteins procaspase-8/procaspase-10 and c-FLIP at the DISC exceeds that of FADD by several-fold. Furthermore, our findings imply that procaspase-8, procaspase-10, and c-FLIP could form DED chains at the DISC, enabling the formation of dimers and efficient activation of caspase-8. Taken together, our findings provide an enhanced understanding of caspase-8 activation and initiation of apoptosis at the DISC.

Paclitaxel enhances therapeutic efficacy of the F8-IL2 immunocytokine to EDA-fibronectin-positive metastatic human melanoma xenografts.

The selective delivery of bioactive agents to tumors reduces toxicity and enhances the efficacy of anticancer therapies. In this study, we show that the antibody F8, which recognizes perivascular and stromal EDA-fibronectin (EDA-Fn), when conjugated to interleukin-2 (F8-IL2) can effectively inhibit the growth of EDA-Fn-expressing melanomas in combination with paclitaxel. We obtained curative effects with paclitaxel administered before the immunocytokine. Coadministration of paclitaxel increased the uptake of F8 in xenografted melanomas, enhancing tumor perfusion and permeability. Paclitaxel also boosted the recruitment of F8-IL2-induced natural killer (NK) cells to the tumor, suggesting a host response as part of the observed therapeutic benefit. In support of this likelihood, NK cell depletion impaired the antitumor effect of paclitaxel plus F8-IL2. Importantly, this combination reduced both the tumor burden and the number of pulmonary metastatic nodules. The combination did not cause cumulative toxicity. Together, our findings offer a preclinical proof that by acting on the tumor stroma paclitaxel potentiates the antitumor activity elicited by a targeted delivery of IL2, thereby supporting the use of immunochemotherapy in the treatment of metastatic melanoma.