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Introduction Quartz Crystal Microbalances (QCMs) are useful devices for chemical sensing, as they are easy to use and display high stability, rapid detection and easy portability. When mass is deposited on the gold electrode, a frequency decrease can be monitored. One application comprises detection of biological targets, such as proteins, viruses or bacteria [1]. Typically, these analytes are assessed in buffers, saline solutions or even real matrices, which are all comparably highly conductive. A change in conductivity may cause unwanted effects on the frequency shifts of a QCM if the set-up is not carefully designed and optimized. There is a strong influence of the ratio of the electrodes exposed to liquid samples (“front side”) and air (”air side”), respectively, on the extent of these frequency shifts [2,3]. Using a dual electrode set-up on one quartz plate gives the opportunity to use the second electrode as a reference, monitoring shifts in the frequency due to temperature changes or unspecific interactions of the analyte with the receptor layer [2,4]. Herein, we report the design of a dual electrode QCM set-up, starting from an electrode design with a small ratio of liquid to air electrode size. By increasing the surface of the liquid electrode side, we were able to achieve small and even frequency responses for both – measurement and reference electrode – upon change of conductivity. Furthermore, the influence of the electrode surfaces on the liquid side were investigated for their performance. QCM set-up 10 MHz Quartz crystals, AT cut (35°15´) with a diameter of 13.8 mm were used. The “air side” electrodes were prepared by screen printing, the liquid side electrodes either by screen printing or sputtering. Before sputtering Au, we first deposited a thin chromium layer onto the substrate to ensure better adhesion for the subsequently sputtered gold layer. Method QCMs were equilibrated in water until recording stable frequency for both electrodes. To assess the effects of different sodium chloride solutions, the measurement cell was flushed with 1 mL of the respective solution. The measurements were performed under stop-flow conditions. After the frequency signals reached stable values, the next solution was added, or the solution was washed out by water. For comparing different electrode designs and surfaces, different concentrations of sodium chloride solutions were tested by comparing the resulting frequency shifts. Results and Conclusions Figure 1 shows two measurement curves recorded with two different dual-electrode designs (screen printed). The first design (Figure 1 A) has a ratio of liquid-to-air side electrodes of 1.25, which seems too small to effectively compensate for unwanted frequency shifts due to conductivity changes. The frequency shifts are not equal for both electrodes and one channel reaches a shift as high as -100 Hz when adding a 2.5 mM sodium chloride solution. However, the second design (Figure 1 B), having the liquid side fully metallized, reveals very substantial improvement over the first one: Adding different sodium chloride solutions leads to small frequency shifts of less than -5 Hz, which are very similar for both electrodes. Therefore, fully metallizing the QCM on the side exposed to liquid samples leads to superior results compared to the previous dual-electrode design comprising two individual electrode pairs. Furthermore, we compared two methods to deposit liquid electrodes, namely screen printing and sputtering. We carried out measurements using newly developed designs for both electrodes and measurement cell, keeping the principle of the liquid electrode side being fully metallized. Figure 2 compares the frequency shifts of both methods for different sodium chloride solutions: Screen printed electrodes show higher total signals and also higher standard deviations. The difference signal of the two electrodes (electrode 1 – electrode 2) was compared too. As can be seen in Figure 2 the frequency differences for different sodium chloride solutions are again higher for screen-printed devices, as are the corresponding standard deviations. These results suggest that screen-printing has weaknesses in terms of covering the whole quartz surface evenly and leads to comparably low reproducibility. On the other hand, sputtering is useful to coat the entire liquid electrode side with gold. This still allows for implementing a reference electrode that monitors frequency shifts due to density changes, while suppressing unwanted shifts caused by conductivity changes. For further work, design performance towards solutions with different viscosities is to be tested. Such an optimized dual electrode design will pave the way improving reproducibility and ruggedness during measurements in real matrices with an included reference electrode on a single quartz plate. References [1] S. Emir Diltemiz, R. Keçili, A. Ersöz, R. Say, Molecular Imprinting Technology in Quartz Crystal Microbalance (QCM) Sensors, Sensors. 17 (2017) 454. doi: 10.3390/s17030454. [2] M. Rodahl, F. Hook, B. Kasemo, QCM operation in liquids: An explanation of measured variations in frequency and Q factor with liquid conductivity, Anal. Chem. 68 (1996) 2219-2227. Doi: 10.1021/ac951203m. [3] U. Latif, A. Mujahid. A. Afzal, R. Sikorski, P.A. Lieberzeit, F.L. Dickert, Dual and tetraelectrode QCMs using imprinted polymers as receptors for inons and neutral analytes, Anal. Bioanal. Chem. 400 (2011) 2507-2515. doi: 10.1007/s00216-011-4927-1 [4] P.A. Lieberzeit, G. Glanznig, M.Jenik, S. Gazda-Miarecka, F. L. Dickert, A. Leidl, Softlithography in Chemical Sensing – Analytes from Molecules to Cells, Sensors. 5 (2005) 509-518. doi: 10.3390/s5120509 Figure 1

Molecularly imprinted polymers (MIP) claim the potential of replacing biological recognition species, such as antibodies, in sensing. This perspective gives a short overview over current techniques for generating surface imprints in polymers, mainly for bioanalytes. It covers both free radical and controlled radical polymerizations that have been the starting point of research in the field. In the course of time, it has become evident that the quality of surface MIP in general increases when growing the polymer in situ from the respective device surface. This has extended the interest for thin film synthesis to electropolymerizable systems, because they allow for controlling deposition in a comparably precise manner. To increase binding capacities and selectivity, post-polymerization modification of systems has also become a focus of interest. Despite highly appreciable success and substantial progress, questions on reproducibility and potential for mass production still remain open.

The canonical WNT signaling pathway is crucial for intestinal stem cell renewal and aberrant WNT signaling is an early event in colorectal cancer (CRC) development. Here, we show for the first time that WNT2 is one of the most significantly induced genes in CRC stroma as compared to normal stroma. The impact of stromal WNT2 on carcinoma formation or progression was not addressed so far. Canonical WNT/β-catenin signaling was assessed using a 7TGP-reporter construct. Furthermore, effects of WNT2 on fibroblast migration and invasion were determined using siRNA-mediated gene silencing. Tumor cell invasion was studied using organotypic raft cultures and in vivo significance was assessed via a xenograft mouse model. We identified cancer-associated fibroblasts (CAFs) as the main source of WNT2. CAF-derived WNT2 activated canonical signaling in adenomatous polyposis coli/β-catenin wild-type colon cancer cells in a paracrine fashion, whereas no hyperactivation was detectable in cell lines harboring mutations in the adenomatous polyposis coli/β-catenin pathway. Furthermore, WNT2 activated autocrine canonical WNT signaling in primary fibroblasts, which was associated with a pro-migratory and pro-invasive phenotype. We identified FZD8 as the putative WNT2 receptor in CAFs. Three-dimensional organotypic co-culture assays revealed that WNT2-mediated fibroblast motility and extracellular matrix remodeling enhanced cancer cell invasion of cell lines even harboring mutations in the adenomatous polyposis coli/β-catenin pathway. Thus, suggesting a tumor-promoting influence on a broad range of CRC. In line, WNT2 also promotes tumor growth, invasion and metastasis in vivo. Moreover, high WNT2 expression is associated with poor prognosis in human CRC. The identification of the pro-malignant function of stromal derived WNT2 in CRC classifies WNT2 and its receptor as promising stromal targets to confine cancer progression in combination with conventional or targeted therapies.

In sourdough processing, lactic acid bacteria (LAB) and yeasts are responsible for the bread's unique characteristics. To evaluate the microbial ecology of traditional Austrian sourdoughs, 11 wheat and nine rye sourdoughs were examined. The colony counts of the LAB ranged from

Many cell lines derived from solid cancers can form spheroids, which recapitulate tumor cell clusters and are more representative of the in vivo situation than 2D cultures. During spheroid formation, a small proportion of a variety of different colon cancer cell lines did not integrate into the sphere and lost cell-cell adhesion properties. An enrichment protocol was developed to augment the proportion of these cells to 100% purity. The basis for the separation of spheroids from non-spheroid forming (NSF) cells is simple gravity-sedimentation. This protocol gives rise to sub-populations of colon cancer cells with stable loss of cell-cell adhesion. SW620 cells lacked E-cadherin, DLD-1 cells lost α-catenin and HCT116 cells lacked P-cadherin in the NSF state. Knockdown of these molecules in the corresponding spheroid-forming cells demonstrated that loss of the respective proteins were indeed responsible for the NSF phenotypes. Loss of the spheroid forming phenotype was associated with increased migration and invasion properties in all cell lines tested. Hence, we identified critical molecules involved in spheroid formation in different cancer cell lines. We present here a simple, powerful and broadly applicable method to generate new sublines of tumor cell lines to study loss of cell-cell adhesion in cancer progression.

Background The t(2;5)(p23;q35) chromosomal translocation results in the expression of the fusion protein NPM/ALK that when expressed in T-lymphocytes gives rise to anaplastic large cell lymphomas (ALCL). In search of new therapy options the dichloromethane extract of the ethnomedicinal plant Neurolaena lobata (L.) R.Br. ex Cass was shown to inhibit NPM/ALK expression. Purpose Therefore, we analysed whether the active principles that were recently isolated and found to inhibit inflammatory responses specifically inhibit growth of NPM/ALK+ ALCL, leukaemia and breast cancer cells, but not of normal cells, and the intravasation through the lymphendothelial barrier. Methods ALCL, leukaemia and breast cancer cells, and normal peripheral blood mononuclear cells (PBMCs) were treated with isolated sesquiterpene lactones and analysed for cell cycle progression, proliferation, mitochondrial activity, apoptosis, protein and mRNA expression, NF-κB and cytochrome P450 activity, 12(S)-HETE production and lymphendothelial intravasation. Results In vitro treatment of ALCL by neurolenin B suppressed NPM/ALK, JunB and PDGF-Rβ expression, inhibited the growth of ALCL cells late in M phase, and induced apoptosis via caspase 3 without compromising mitochondrial activity (as a measure of general exogenic toxicity). Moreover, neurolenin B attenuated tumour spheroid intravasation probably through inhibition of NF-κB and CYP1A1. Conclusion Neurolenin B specifically decreased pro-carcinogenic NPM/ALK expression in ALK+ ALCL cells and, via the inhibition of NF-kB signalling, attenuated tumour intra/extravasation into the lymphatics. Hence, neurolenin B may open new options to treat ALCL and to manage early metastatic processes to which no other therapies exist.

Background Hypoxic and necrotic regions that accrue within solid tumors in vivo are known to be associated with metastasis formation, radio- and chemotherapy resistance, and drug metabolism. Therefore, integration of these tumor characteristics into in vitro drug screening models is advantageous for any reliable investigation of the anticancer activity of novel drug candidates. In general, usage of cell culture models with in vivo like characteristics has become essential in preclinical drug studies and allows evaluation of complex problems such as tumor selectivity and anti-invasive properties of the drug candidates. Materials and Methods In this study, we investigated the anticancer activity of clinically approved, investigational and experimental drugs based on platinum (cisplatin, oxaliplatin and KP1537), gallium (KP46), ruthenium (KP1339) and lanthanum (KP772) in different cell culture models such as monolayers, multicellular spheroids, as well as invasion and metastasis models. Results Application of the Alamar Blue assay to multicellular spheroids and a spheroid-based invasion assay resulted in an altered rating of compounds with regard to their cytotoxicity and ability to inhibit invasion when compared with monolayer-based cytotoxicity and transwell assays. For example, the gallium-based drug candidate KP46 showed in spheroid cultures significantly enhanced properties to inhibit protrusion formation and fibroblast mediated invasiveness, and improved cancer cell selectivity. Conclusion Taken together, our results demonstrate the advantages of spheroid-based assays and underline the necessity of using different experimental models for reliable preclinical investigations assessing and better predicting the anticancer potential of new compounds.

Anti-cancer drug development is inefficient, mostly due to lack of efficacy in human patients. The high fail rate is partly due to the lack of predictive models or the inadequate use of existing preclinical test systems. However, progress has been made and preclinical models were improved or newly developed, which all account for basic features of solid cancers, three-dimensionality and heterotypic cell interaction. Here we give an overview of available in vivo and in vitro models of cancer, which meet the criteria of being 3D and mirroring human tumor-stroma interactions. We only focus on drug response models without touching models for pharmacokinetic and dynamic, toxicity or delivery aspects.

Spheroid-based cellular screening approaches represent a highly physiologic experimental setup to identify novel anticancer drugs and an innovative preclinical model to reduce the high failure rate of anticancer compounds in clinical trials. The resazurin reduction (RR) assay, known as the alamarBlue or CellTiter-Blue assay, is frequently used to determine cell viability/proliferation capacity in eukaryotic cells. Whether this assay is applicable to assess viability in multicellular spheroids has not been evaluated. We analyzed the RR assay to measure cytotoxic and/or cytostatic responses in tumor cell spheroids compared with conventional 2D cultures. We found that tight cell-cell interactions in compact spheroids hamper resazurin uptake and its subsequent reduction to resorufin, leading to lowered reduction activity in relation to the actual cellular health/cell number. Treatment with staurosporine disrupted close cell-cell contacts, which increased resazurin reduction compared with untreated controls. Loss of tight junctions by trypsinization or addition of EGTA or EDTA restored high resazurin reduction rates in untreated spheroids. In conclusion, the RR assay is unsuited to quantitatively measure cellular health/cell number in compact spheroids. However, it can be used to distinguish between cytotoxic versus cytostatic compounds in spheroids. Restoration of the correlation of cell viability/number to resazurin reduction capacity can be achieved by disruption of tight junctions.

Determining the migratory and invasive capacity of tumor and stromal cells and clarifying the underlying mechanisms is most relevant for novel strategies in cancer diagnosis, prognosis, drug development and treatment. Here we shortly summarize the different modes of cell travelling and review in vitro methods, which can be used to evaluate migration and invasion. We provide a concise summary of established migration/invasion assays described in the literature, list advantages, limitations and drawbacks, give a tabular overview for convenience and depict the basic principles of the assays graphically. In many cases particular research problems and specific cell types do not leave a choice for a broad variety of usable assays. However, for most standard applications using adherent cells, based on our experience we suggest to use exclusion zone assays to evaluate migration/invasion. We substantiate our choice by demonstrating that the advantages outbalance the drawbacks e.g. the simple setup, the easy readout, the kinetic analysis, the evaluation of cell morphology and the feasibility to perform the assay with standard laboratory equipment. Finally, innovative 3D migration and invasion models including heterotypic cell interactions are discussed. These methods recapitulate the in vivo situation most closely. Results obtained with these assays have already shed new light on cancer cell spreading and potentially will uncover unknown mechanisms.

The insulin-like growth factor (IGF)2/IGF1 receptor (IGF1R) signaling axis has an important role in intestinal carcinogenesis and overexpression of IGF2 is an accepted risk factor for colorectal cancer (CRC) development. Genetic amplifications and loss of imprinting contribute to the upregulation of IGF2, but insufficiently explain the extent of IGF2 expression in a subset of patients. Here, we show that IGF2 was specifically induced in the tumor stroma of CRC and identified cancer-associated fibroblasts (CAFs) as the major source. Further, we provide functional evidence that stromal IGF2, via the paracrine IGF1R/insulin receptor axis, activated pro-survival AKT signaling in CRC cell lines. In addition to its effects on malignant cells, autocrine IGF2/IGF1R signaling in CAFs induced myofibroblast differentiation in terms of alpha-smooth muscle actin expression and contractility in floating collagen gels. This was further augmented in concert with transforming growth factor-β (TGFβ) signaling suggesting a cooperative mechanism. However, we demonstrated that IGF2 neither induced TGFβ/smooth muscle actin/mothers against decapentaplegic (SMAD) signaling nor synergized with TGFβ to hyperactivate this pathway in two dimensional and three dimensional cultures. IGF2-mediated physical matrix remodeling by CAFs, but not changes in extracellular matrix-modifying proteases or other secreted factors acting in a paracrine manner on/in cancer cells, facilitated subsequent tumor cell invasion in organotypic co-cultures. Consistently, colon cancer cells co-inoculated with CAFs expressing endogenous IGF2 in mouse xenograft models exhibited elevated invasiveness and dissemination capacity, as well as increased local tumor regrowth after primary tumor resection compared with conditions with IGF2-deficient CAFs. In line, expression of IGF2 correlated with elevated relapse rates and poor survival in CRC patients. In agreement with our results, high-level coexpression of IGF2 and TGFβ was predicting adverse outcome with higher accuracy than increased expression of the individual genes alone. Taken together, we demonstrate that stroma-induced IGF2 promotes colon cancer progression in a paracrine and autocrine manner and propose IGF2 as potential target for tumor stroma cotargeting strategies.

Three-dimensional (3D) cancer models are used as preclinical systems to mimic physiologic drug responses. We provide evidence for strong changes of proliferation and metabolic capacity in three dimensions by systematically analyzing spheroids of colon cancer cell lines. Spheroids showed relative lower activities in the AKT, mammalian target of rapamycin (mTOR) and S6K (also known as RPS6KB1) signaling pathway compared to cells cultured in two dimensions. We identified spatial alterations in signaling, as the level of phosphorylated RPS6 decreased from the spheroid surface towards the center, which closely coordinated with the tumor areas around vessels in vivo These 3D models displayed augmented anti-tumor responses to AKT-mTOR-S6K or mitogen-activated protein kinase (MAPK) pathway inhibition compared to those in 2D models. Inhibition of AKT-mTOR-S6K resulted in elevated ERK phosphorylation in 2D culture, whereas under these conditions, ERK signaling was reduced in spheroids. Inhibition of MEK1 (also known as MAP2K1) led to decreased AKT-mTOR-S6K signaling in 3D but not in 2D culture. These data indicate a distinct rewiring of signaling in 3D culture and during treatment. Detached tumor-cell clusters in vessels, in addition to circulating single tumor cells, play a putative role in metastasis in human cancers. Hence, the understanding of signaling in spheroids and the responses in the 3D models upon drug treatment might be beneficial for anti-cancer therapies.

Three-dimensional (3D) cancer models are used as preclinical systems to mimic physiologic drug responses. We provide evidence for strong changes of proliferation and metabolic capacity in three dimensions by systematically analyzing spheroids of colon cancer cell lines. Spheroids showed relative lower activities in the AKT, mammalian target of rapamycin (mTOR) and S6K (also known as RPS6KB1) signaling pathway compared to cells cultured in two dimensions. We identified spatial alterations in signaling, as the level of phosphorylated RPS6 decreased from the spheroid surface towards the center, which closely coordinated with the tumor areas around vessels in vivo These 3D models displayed augmented anti-tumor responses to AKT-mTOR-S6K or mitogen-activated protein kinase (MAPK) pathway inhibition compared to those in 2D models. Inhibition of AKT-mTOR-S6K resulted in elevated ERK phosphorylation in 2D culture, whereas under these conditions, ERK signaling was reduced in spheroids. Inhibition of MEK1 (also known as MAP2K1) led to decreased AKT-mTOR-S6K signaling in 3D but not in 2D culture. These data indicate a distinct rewiring of signaling in 3D culture and during treatment. Detached tumor-cell clusters in vessels, in addition to circulating single tumor cells, play a putative role in metastasis in human cancers. Hence, the understanding of signaling in spheroids and the responses in the 3D models upon drug treatment might be beneficial for anti-cancer therapies.

The development of novel anticancer drugs is far from being efficient, mostly due to lack of efficacy in human patients. The 95% attrition rate in the clinic is predominantly owing to the shortage of predictive preclinical models. However, during recent decades in vitro and in vivo preclinical models were engineered, better recapitulating the molecular basis of human cancers, the three-dimensional environment, the cellular heterogeneity or combining the above-mentioned features. Here suitable preclinical in vitro and in vivo cancer models for drug response testing are discussed and advantages and drawbacks of each model are highlighted.

Prostate cancer (PCa) is the most prevalent cancer in men. Hyperactive STAT3 is thought to be oncogenic in PCa. However, targeting of the IL-6/STAT3 axis in PCa patients has failed to provide therapeutic benefit. Here we show that genetic inactivation of Stat3 or IL-6 signalling in a Pten-deficient PCa mouse model accelerates cancer progression leading to metastasis. Mechanistically, we identify p19(ARF) as a direct Stat3 target. Loss of Stat3 signalling disrupts the ARF-Mdm2-p53 tumour suppressor axis bypassing senescence. Strikingly, we also identify STAT3 and CDKN2A mutations in primary human PCa. STAT3 and CDKN2A deletions co-occurred with high frequency in PCa metastases. In accordance, loss of STAT3 and p14(ARF) expression in patient tumours correlates with increased risk of disease recurrence and metastatic PCa. Thus, STAT3 and ARF may be prognostic markers to stratify high from low risk PCa patients. Our findings challenge the current discussion on therapeutic benefit or risk of IL-6/STAT3 inhibition.

Background: The intravasation of breast cancer into the lymphendothelium is an early step of metastasis. Little is known about the mechanisms of bulky cancer invasion into lymph ducts. Methods: To particularly address this issue, we developed a 3-dimensional co-culture model involving MCF-7 breast cancer cell spheroids and telomerase-immortalised human lymphendothelial cell (LEC) monolayers, which resembles intravasation in vivo and correlated the malignant phenotype with specific protein expression of LECs. Results: We show that tumour spheroids generate ‘circular chemorepellent-induced defects' (CCID) in LEC monolayers through retraction of LECs, which was induced by 12(S)-hydroxyeicosatetraenoic acid (HETE) secreted by MCF-7 spheroids. This 12(S)-HETE-regulated retraction of LECs during intravasation particularly allowed us to investigate the key regulators involved in the motility and plasticity of LECs. In all, 12(S)-HETE induced pro-metastatic protein expression patterns and showed NF-κB-dependent up-regulation of the mesenchymal marker protein S100A4 and of transcriptional repressor ZEB1 concomittant with down-regulation of the endothelial adherence junction component VE-cadherin. This was in accordance with ∼50% attenuation of CCID formation by treatment of cells with 10 μ Bay11-7082. Notably, 12(S)-HETE-induced VE-cadherin repression was regulated by either NF-κB or by ZEB1 since ZEB1 siRNA knockdown abrogated not only 12(S)-HETE-mediated VE-cadherin repression but inhibited VE-cadherin expression in general. Interpretation: These data suggest an endothelial to mesenchymal transition-like process of LECs, which induces single cell motility during endothelial transmigration of breast carcinoma cells. In conclusion, this study demonstrates that the 12(S)-HETE-induced intravasation of MCF-7 spheroids through LECs require an NF-κB-dependent process of LECs triggering the disintegration of cell–cell contacts, migration, and the generation of CCID.

Genomic imprinting is an epigenetic process that results in parental-specific gene expression. Advances in understanding the mechanism that regulates imprinted gene expression in mammals have largely depended on generating targeted manipulations in embryonic stem (ES) cells that are analysed in vivo in mice. However, genomic imprinting consists of distinct developmental steps, some of which occur in post-implantation embryos,indicating that they could be studied in vitro in ES cells. The mouse Igf2r gene shows imprinted expression only in post-implantation stages, when repression of the paternal allele has been shown to require cis-expression of the Airn non-coding (nc) RNA and to correlate with gain of DNA methylation and repressive histone modifications. Here we follow the gain of imprinted expression of Igf2r during in vitro ES cell differentiation and show that it coincides with the onset of paternal-specific expression of the Airn ncRNA. Notably, although Airn ncRNA expression leads, as predicted, to gain of repressive epigenetic marks on the paternal Igf2r promoter, we unexpectedly find that the paternal Igf2r promoter is expressed at similar low levels throughout ES cell differentiation. Our results further show that the maternal and paternal Igf2r promoters are expressed equally in undifferentiated ES cells,but during differentiation expression of the maternal Igf2r promoter increases up to 10-fold, while expression from the paternal Igf2rpromoter remains constant. This indicates, contrary to expectation, that the Airn ncRNA induces imprinted Igf2r expression not by silencing the paternal Igf2r promoter, but by generating an expression bias between the two parental alleles.

Solid cancers are not simple accumulations of malignant tumor cells but rather represent complex organ-like structures. Despite a more chaotic general appearance as compared to the highly organized setup of healthy tissues, cancers still show highly differentiated structures and a close interaction with and dependency on the interwoven connective tissue. This complexity within cancers is not known in detail at the molecular level so far. The first part of this article will shortly describe the technology and strategies to quantify and dissect the heterogeneity in human solid cancers. Moreover, there is urgent need to better understand human cancer biology since the development of novel anti-cancer drugs is far from being efficient, predominantly due to the scarcity of predictive preclinical models. Hence, in vivo and in vitro models were developed, which better recapitulate the complexity of human cancers, by their intrinsic three-dimensional nature and the cellular heterogeneity and allow functional intervention for hypothesis testing. Therefore, in the second part 3D in vitro cancer models are presented that analyze and depict the heterogeneity in human cancers. Advantages and drawbacks of each model are highlighted and their suitability to preclinical drug testing is discussed.

An apolar extract of the traditional medicinal plant Neurolaena lobata inhibited the expression of the NPM/ALK chimera, which is causal for the majority of anaplastic large cell lymphomas (ALCLs). Therefore, an active principle of the extract, the furanoheliangolide sesquiterpene lactone lobatin B, was isolated and tested regarding the inhibition of ALCL expansion and tumour cell intravasation through the lymphendothelium. ALCL cell lines, HL-60 cells and PBMCs were treated with plant compounds and the ALK inhibitor TAE-684 to measure mitochondrial activity, proliferation and cell cycle progression and to correlate the results with protein- and mRNA-expression of selected gene products. Several endpoints indicative for cell death were analysed after lobatin B treatment. Tumour cell intravasation through lymphendothelial monolayers was measured and potential causal mechanisms were investigated analysing NF-κB- and cytochrome P450 activity, and 12(S)-HETE production. Lobatin B inhibited the expression of NPM/ALK, JunB and PDGF-Rβ, and attenuated proliferation of ALCL cells by arresting them in late M phase. Mitochondrial activity remained largely unaffected upon lobatin B treatment. Nevertheless, caspase 3 became activated in ALCL cells. Also HL-60 cell proliferation was attenuated whereas PBMCs of healthy donors were not affected by lobatin B. Additionally, tumour cell intravasation, which partly depends on NF-κB, was significantly suppressed by lobatin B most likely due to its NF-κB-inhibitory property. Lobatin B, which was isolated from a plant used in ethnomedicine, targets malignant cells by at least two properties: I) inhibition of NPM/ALK, thereby providing high specificity in combating this most prevalent fusion protein occurring in ALCL; II) inhibition of NF-κB, thereby not affecting normal cells with low constitutive NF-κB activity. This property also inhibits tumour cell intravasation into the lymphatic system and may provide an option to manage this early step of metastatic progression.

Cartilage-specific proteins are considered potential autoantigens that could continuously fuel autoimmune responses directed to the joints in rheumatoid arthritis (RA). Using recombinant chimeric collagen type II we have identified one major type II collagen (CII) epitope (denoted U1) recognized by RA sera. The U1 epitope is a triple helical structure formed by 11 amino acids (triple helical position 494–504) and colocalizes with the recently described α1β1/α2β1 integrin binding site. It is a major epitope, found in 14/22 RA sera positive for antibodies to CII. One individual could be followed for a long time and the results showed that IgG antibodies specific for the U1 epitope were maintained along the chronic disease course but suppressed during periods of cyclosporin A and anti-CD4 treatment. We also found that the U1 epitope was recognized in rats susceptible to collagen-induced arthritis. A monoclonal autoantibody (mAb 126.30) was raised from DA rats, which bound the same epitope. The antibodies bound the cartilage in vivo showing that the epitope is exposed to the immune system for immune complex formation in the intact joint.

Identification of a clinically relevant immunodominant region out lung hemorrhage. The pathogenic process is driven of type IV collagen in Goodpasture disease. by antibodies to type IV collagen, one of the main struc- Background. The characteristic feature of Goodpasture dis- tural components of basement membranes. These auto- ease is the occurrence of an autoantibody response to the antibodies can be detected as circulating antibodies or noncollagenous domain of the a3 chain of type IV collagen as linear deposits of IgG in the affected basement mem- (a3(IV)NC1) in the alveolar and glomerular basement mem- brane. These antibodies are associated with the development branes. Studies have revealed that the major antigenic of a rapidly progressive glomerulonephritis, with or without epitopes are located in the C-terminal region of the lung hemorrhage, whereas autoantibodies specific for the other a3(IV) chain (1, 2), one of the six known a(IV) chains a chains of the heterotrimeric type IV collagen probably do (3). In this region, each chain is folded into a globular not cause disease. In this study, we have investigated whether domain (4), called the NC1 domain. The limited distribu- differences in fine specificity of autoimmune recognition of the tion of the a3(IV) chain (5), mainly in glomerular and a3(IV)NC1 correlate with clinical outcome. Methods. For mapping of antibody binding to type IV colla- alveolar basement membranes, correlates well with the gen, chimeric collagen constructs were generated in which parts organ involvement in Goodpasture disease. of the a3(IV)NC1 domain were replaced by the corresponding There are several reports discussing specificity of the sequences of homologous nonreactive a1(IV). The different Goodpasture autoantibodies and their epitopes. The epi- recombinant collagen chimeras allowed the analysis of anti- tope has been shown to be a conformational epitope

The activated tumor stroma participates in many processes that control tumorigenesis, including tumor cell growth, invasion and metastasis. Cancer-associated fibroblasts (CAFs) represent the major cellular component of the stroma and are the main source for connective tissue components of the extracellular matrix and various classes of proteolytic enzymes. The signaling pathways involved in the interactions between tumor and stromal cells and the molecular characteristics that distinguish normal 'resting' fibroblasts from cancer-associated or '-activated' fibroblasts remain poorly defined. Recent studies emphasized the prognostic and therapeutic significance of CAF-related molecular signatures and a number of those genes have been shown to serve as putative therapeutic targets. We have used immuno-laser capture microdissection and whole-genome Affymetrix GeneChip analysis to obtain transcriptional signatures from the activated tumor stroma of colon carcinomas that were compared with normal resting colonic fibroblasts. Several members of the Wnt-signaling pathway and gene sets related to hypoxia, epithelial-to-mesenchymal transition (EMT) and transforming growth factor-β (TGFβ) pathway activation were induced in CAFs. The putative TGFβ-target IGFBP7 was identified as a tumor stroma marker of epithelial cancers and as a tumor antigen in mesenchyme-derived sarcomas. We show here that in contrast to its tumor-suppressor function in epithelial cells, IGFPB7 can promote anchorage-independent growth in malignant mesenchymal cells and in epithelial cells with an EMT phenotype when IGFBP7 is expressed by the tumor cells themselves and can induce colony formation in colon cancer cells co-cultured with IGFBP7-expressing CAFs by a paracrine tumor-stroma interaction.

The present study investigates extracts of Neuolaena lobata, an anti-protozoan ethnomedicinal plant of the Maya, regarding its anti-neoplastic properties. Firstly, extracts of increasing polarity were tested in HL-60 cells analyzing inhibition of cell proliferation and apoptosis induction. Secondly, the most active extract was further tested in anaplastic large cell lymphoma (ALCL) cell lines of human and mouse origin. The dichloromethane extract inhibited proliferation of HL-60, human and mouse ALCL cells with an IC50 of ~2.5, 3.7 and 2.4 µg/ml, respectively and arrested cells in the G2/M phase. The extract induced the checkpoint kinases Chk1 and Chk2 and perturbed the orchestrated expression of the Cdc25 family of cell cycle phosphatases which was paralleled by the activation of p53, p21 and downregulation of c-Myc. Importantly, the expression of NPM/ALK and its effector JunB were drastically decreased, which correlated with the activation of caspase 3. Subsequently also platelet derived growth factor receptor β was downregulated, which was recently shown to be transcriptionally controlled by JunB synergizing with ALK in ALCL development. We show that a traditional healing plant extract downregulates various oncogenes, induces tumor suppressors, inhibits cell proliferation and triggers apoptosis of malignant cells. The discovery of the 'Active Principle(s)' is warranted.

Investigating the bioactivity of traditional medical remedies under the controlled conditions of a laboratory is an option to find additional applications, novel formulations or lead structures for the development of new drugs. The present work analysed the anti‑neoplastic activity of increasing polar extracts of the rainforest plant Critonia morifolia (Asteraceae) that has been successfully used as traditional remedy to treat various inflammatory conditions in the long-lasting medical tradition of the Central American Maya, which was here also confirmed in vitro. The apolar petroleum ether extract exhibited the most potent anti‑proliferative and pro‑apoptotic effects in HL‑60 cells and triggered down-regulation of Cdc25C and cyclin D1 within 30 min followed by the inhibition of c-Myc expression and the onset of caspase-3 activation within 2 h. Subsequent to these very rapid molecular responses Chk2 and H2AX became phosphorylated (γ‑H2AX) after 4 h. Analysis of the cell cycle distribution showed an accumulation of cells in the G2-M phase within 8 h and after 24 h in S-phase. This was temporally paralleled by the down-regulation of Cdc25A, Cdc25B, Wee1 and Akt. Therefore, the attenuation of cell cycle progression in the G2-M phase was consistent with the known role of Chk2 for G2-M arrest and with the role of Cdc25B in S-phase progression. These findings suggest the presence of two distinct active principles in the petroleum ether extract of C. moriflia. These facilitated the strong apoptotic response evidenced by the rapid activation of caspase-3 that was later enforced by the inhibition of the survival kinase Akt. Importantly, the efficient down-regulation of Akt, which is successfully tested in current clinical trials, is a unique property of C. morifolia.

Introduction. Several studies demonstrated that anti-inflammatory remedies exhibit excellent anti-neoplastic properties. An extract ofPluchea odorata(Asteraceae), which is used for wound healing and against inflammatory conditions, was fractionated and properties correlating to anti-neoplastic and wound healing effects were separated.Methods. Up to six fractionation steps using silica gel, Sephadex columns, and distinct solvent systems were used, and eluted fractions were analysed by thin layer chromatography, apoptosis, and proliferation assays. The expression of oncogenes and proteins regulating cell migration was investigated by immunoblotting after treating HL60 cells with the most active fractions.Results. Sequential fractionations enriched anti-neoplastic activities which suppressed oncogene expression of JunB, c-Jun, c-Myc, and Stat3. Furthermore, a fraction (F4.6.3) inducing or keeping up expression of the mobility markers MYPT, ROCK1, and paxillin could be separated from another fraction (F4.3.7), which inhibited these markers.Conclusions. Wound healing builds up scar or specific tissue, and hence, compounds enhancing cell migration support this process. In contrast, successful anti-neoplastic therapy combats tumour progression, and thus, suppression of cell migration is mandatory.

Collagen-induced arthritis (CIA) is a widely used model for rheumatoid arthritis. Induction of CIA in rats using rat type II collagen (CII) results in a chronic arthritis in which anti-CII antibodies are believed to play a pathogenic role. In this study, we analyzed the epitope selection and V gene usage in the anti-CII response in the DA rat. A panel of CII-reactive B cell hybridomas was established from the draining lymph nodes 11 days after immunization. All of the CII-specific antibodies bound cartilage in vivo, showing that these are true autoantibodies. These antibodies were all IgG and specific for several distinct triple helical epitopes on CII. Interestingly, the major epitope, recognized by four different antibodies, was identical with the major B cell epitope in the mouse CII located at position 359--369 (denoted as C1(III)). The Q52 and PC7183 V(H) gene families encoded 12 out of 14 sequenced heavy chains. There was a relatively more heterogeneous usage of V(L) genes as the antibodies were encoded by four different V(kappa) families (V(kappa)1, V(kappa)2, V(kappa)12/13 and V(kappa)RF). As in the mouse, some of the V genes used showed germline characteristics. We conclude that the immune response in the rat shares epitope specificity and a constrained V gene repertoire with the mouse. However, the V genes used for recognition of the closely related collagen structures differed considerably between mouse and rat, indicating an influence of the species-specific variation in the V gene repertoire.

Natural products continue to represent the main source for therapeutics, and ethnopharmacological remedies from high biodiversity regions are a rich source for the development of novel drugs. Hence, in our attempt to find new anti-neoplastic activities we focused on ethno-medicinal plants of the Maya, who live in the world's third richest area in vascular plant species. Pluchea odorata (Asteraceae) is traditionally used for the treatment of various inflammatory disorders and recently, the in vitro anti-cancer activities of different extracts of this plant were described. Here, we present the results of bioassay-guided fractionations of the dichloromethane extract of P. odorata that aimed to enrich the active principles. The separation resulted in fractions which showed the dissociation of two distinct anti-neoplastic mechanisms; firstly, a genotoxic effect that was accompanied by tubulin polymerization, cell cycle arrest, and apoptosis (fraction F2/11), and secondly, an effect that interfered with the orchestrated expression of Cyclin D1, Cdc25A, and Cdc2 and that also led to cell cycle arrest and apoptosis (fraction F3/4). Thus, the elimination of generally toxic properties and beyond that the development of active principles of P. odorata, which disturb cancer cell cycle progression, are of interest for potential future therapeutic concepts against proliferative diseases.