Oxidative changes and signalling pathways are pivotal in initiating age-related changes in articular cartilage.

Ann Rheum Dis. 2016 Feb;75(2):449-58

Authors: Hui W, Young DA, Rowan AD, Xu X, Cawston TE, Proctor CJ

Abstract
OBJECTIVE: To use a computational approach to investigate the cellular and extracellular matrix changes that occur with age in the knee joints of mice.
METHODS: Knee joints from an inbred C57/BL1/6 (ICRFa) mouse colony were harvested at 3-30 months of age. Sections were stained with H&E, Safranin-O, Picro-sirius red and antibodies to matrix metalloproteinase-13 (MMP-13), nitrotyrosine, LC-3B, Bcl-2, and cleaved type II collagen used for immunohistochemistry. Based on this and other data from the literature, a computer simulation model was built using the Systems Biology Markup Language using an iterative approach of data analysis and modelling. Individual parameters were subsequently altered to assess their effect on the model.
RESULTS: A progressive loss of cartilage matrix occurred with age. Nitrotyrosine, MMP-13 and activin receptor-like kinase-1 (ALK1) staining in cartilage increased with age with a concomitant decrease in LC-3B and Bcl-2. Stochastic simulations from the computational model showed a good agreement with these data, once transforming growth factor-β signalling via ALK1/ALK5 receptors was included. Oxidative stress and the interleukin 1 pathway were identified as key factors in driving the cartilage breakdown associated with ageing.
CONCLUSIONS: A progressive loss of cartilage matrix and cellularity occurs with age. This is accompanied with increased levels of oxidative stress, apoptosis and MMP-13 and a decrease in chondrocyte autophagy. These changes explain the marked predisposition of joints to develop osteoarthritis with age. Computational modelling provides useful insights into the underlying mechanisms involved in age-related changes in musculoskeletal tissues.

PMID: 25475114 [PubMed - indexed for MEDLINE]

18 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results:

("orphan disease" OR "rare disease" OR "orphan diseases" OR "rare diseases")

These pubmed results were generated on 2016/06/28

PubMed comprises more than 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

16 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results:

"Cystic Fibrosis"

These pubmed results were generated on 2016/06/28

PubMed comprises more than 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

Inflammatory pathway network-based drug repositioning and molecular phenomics.

Mol Biosyst. 2016 Jun 27;

Authors: Gu J, Crosier PS, Hall CJ, Chen L, Xu X

Abstract
Inflammation is a protective biological response to body/tissue damage that involves immune cells, blood vessels and molecular mediators. In this work, we constructed the pathway network of inflammation, including 11 sub-pathways of inflammatory factors. Pathway-based network efficiency and network flux were adopted to evaluate drug efficacy. By using approved and experimentally validated anti-inflammatory drugs as training sets, a predictive model was built to screen potential anti-inflammatory drugs from approved drugs in DrugBank. This drug repositioning approach would bring a fast and cheap way to find new indications for approved drugs. Moreover, molecular phenomics profiles of the expression of inflammatory factors will provide new insight into the drug mechanism of action.

PMID: 27345454 [PubMed - as supplied by publisher]

Bedaquiline, an FDA-approved antibiotic, inhibits mitochondrial function and potently blocks the proliferative expansion of stem-like cancer cells (CSCs).

Aging (Albany NY). 2016 Jun 22;

Authors: Fiorillo M, Lamb R, Tanowitz HB, Cappello AR, Martinez-Outschoorn UE, Sotgia F, Lisanti MP

Abstract
Bedaquiline (a.k.a., Sirturo) is an anti-microbial agent, which is approved by the FDA for the treatment of multi-drug resistant pulmonary tuberculosis (TB). Bedaquiline is a first-in-class diaryl-quinoline compound, that mechanistically inhibits the bacterial ATP-synthase, and shows potent activity against both drug-sensitive and drug-resistant TB. Interestingly, eukaryotic mitochondria originally evolved from engulfed aerobic bacteria. Thus, we hypothesized that, in mammalian cells, bedaquiline might also target the mitochondrial ATP-synthase, leading to mitochondrial dysfunction and ATP depletion. Here, we show that bedaquiline has anti-cancer activity, directed against Cancer Stem-like Cells (CSCs). More specifically, we demonstrate that bedaquiline treatment of MCF7 breast cancer cells inhibits mitochondrial oxygen-consumption, as well as glycolysis, but induces oxidative stress. Importantly, bedaquiline significantly blocks the propagation and expansion of MCF7-derived CSCs, with an IC-50 of approx. 1-μM, as determined using the mammosphere assay. Similarly, bedaquiline also reduces both the CD44+/CD24low/- CSC and ALDH+ CSC populations, under anchorage-independent growth conditions. In striking contrast, bedaquiline significantly increases oxygen consumption in normal human fibroblasts, consistent with the fact that it is well-tolerated in patients treated for TB infections. As such, future pre-clinical studies and human clinical trials in cancer patients may be warranted. Interestingly, we also highlight that bedaquiline shares certain structural similarities with trans-piceatannol and trans-resveratrol, which are known natural flavonoid inhibitors of the mitochondrial ATP-synthase (complex V) and show anti-aging properties.

PMID: 27344270 [PubMed - as supplied by publisher]

Antihypertensive therapy in pre-eclampsia: effects of plasma from nonresponsive patients on endothelial gene expression.

Pharmacogenomics. 2016 Jun 27;

Authors: Luizon MR, Caldeira-Dias M, Deffune E, Fernandes KS, Cavalli RC, Tanus-Santos JE, Sandrim VC

Abstract
AIM: Over 40% of patients with pre-eclampsia are nonresponsive to antihypertensive therapy, but the underlying mechanisms are unknown. We examined the effects of plasma from nonresponsive and responsive patients on endothelial gene expression.
PATIENTS & METHODS: PCR array was performed in human umbilical vein endothelial cells (HUVEC) incubated with plasma from nonresponsive (n = 4) and responsive (n = 4) patients. Gene networks and interactions with antihypertensive drugs used in pre-eclampsia were identified by Ingenuity Pathway Analysis.
RESULTS: Nifedipine and hydralazine act by upregulate or downregulate genes found to be downregulated or upregulated in HUVEC incubated with plasma from nonresponsive patients.
CONCLUSION: Our novel findings suggest that plasma from nonresponsive and responsive patients evoke different responses in HUVEC, and might advance the pharmacogenomics research in pre-eclampsia.

PMID: 27348131 [PubMed - as supplied by publisher]

Computational Analysis of Single Nucleotide Polymorphisms Associated with Altered Drug Responsiveness in Type 2 Diabetes.

Int J Mol Sci. 2016;17(7)

Authors: Costa V, Federico A, Pollastro C, Ziviello C, Cataldi S, Formisano P, Ciccodicola A

Abstract
Type 2 diabetes (T2D) is one of the most frequent mortality causes in western countries, with rapidly increasing prevalence. Anti-diabetic drugs are the first therapeutic approach, although many patients develop drug resistance. Most drug responsiveness variability can be explained by genetic causes. Inter-individual variability is principally due to single nucleotide polymorphisms, and differential drug responsiveness has been correlated to alteration in genes involved in drug metabolism (CYP2C9) or insulin signaling (IRS1, ABCC8, KCNJ11 and PPARG). However, most genome-wide association studies did not provide clues about the contribution of DNA variations to impaired drug responsiveness. Thus, characterizing T2D drug responsiveness variants is needed to guide clinicians toward tailored therapeutic approaches. Here, we extensively investigated polymorphisms associated with altered drug response in T2D, predicting their effects in silico. Combining different computational approaches, we focused on the expression pattern of genes correlated to drug resistance and inferred evolutionary conservation of polymorphic residues, computationally predicting the biochemical properties of polymorphic proteins. Using RNA-Sequencing followed by targeted validation, we identified and experimentally confirmed that two nucleotide variations in the CAPN10 gene-currently annotated as intronic-fall within two new transcripts in this locus. Additionally, we found that a Single Nucleotide Polymorphism (SNP), currently reported as intergenic, maps to the intron of a new transcript, harboring CAPN10 and GPR35 genes, which undergoes non-sense mediated decay. Finally, we analyzed variants that fall into non-coding regulatory regions of yet underestimated functional significance, predicting that some of them can potentially affect gene expression and/or post-transcriptional regulation of mRNAs affecting the splicing.

PMID: 27347941 [PubMed - as supplied by publisher]

The potential of genetically guided treatment in Behçet's disease.

Pharmacogenomics. 2016 Jun 27;

Authors: Gheita TA, Gheita HA, Kenawy SA

Abstract
Continuous identification of specific targets and candidate genes together with novel approaches offers new promises for the future of gene therapy design in Behçet's disease (BD). Personalized medicine based on pharmacogenomics is being developed at the clinical stage to improve treatment response. Screening the whole gene and regulatory regions is important when searching for novel variants associated with such complex diseases. Different host genetic factors play significant roles in susceptibility to BD. Thus, identifying these genes responsible for susceptibility and resistance to BD may offer a notable contribution toward understanding its pathogenesis, and may lead to the development of novel prophylactic and treatment strategies. Evidenced-based treatment strategy is recommended for the management in BD patients. This review sheds light on the immunopathogenesis and pharmacogenetics of BD with special attention to the treatment targeting gene polymorphisms. In conclusion, the potential of genetically guided treatment in BD takes us back to the future for an accurate management strategy of this serious rheumatic disease. The ongoing discovery of pivotal genes related to the susceptibility, manifestations, disease activity and treatment options provide substantial hope to the reduced frequency of BD, effective control and improvement in the prognosis. Targeted gene therapy could be a leading option in the treatment armamentarium of BD.

PMID: 27347725 [PubMed - as supplied by publisher]

Decoupling kinematics and mechanics reveals coding properties of trigeminal ganglion neurons in the rat vibrissal system.

Elife. 2016 Jun 27;5

Authors: Bush NE, Schroeder CL, Hobbs JA, Yang AE, Huet LA, Solla SA, Hartmann MJ

Abstract
Tactile information available to the rat vibrissal system begins as external forces that cause whisker deformations, which in turn excite mechanoreceptors in the follicle. Despite the fundamental mechanical origin of tactile information, primary sensory neurons in the trigeminal ganglion (Vg) have often been described as encoding the kinematics (geometry) of object contact. Here we aimed to determine the extent to which Vg neurons encode the kinematics vs. mechanics of contact. We used models of whisker bending to quantify mechanical signals (forces and moments) at the whisker base while simultaneously monitoring whisker kinematics and recording single Vg units in both anesthetized rats and awake, body restrained rats. We employed a novel manual stimulation technique to deflect whiskers in a way that decouples kinematics from mechanics, and used Generalized Linear Models (GLMs) to show that Vg neurons more directly encode mechanical signals when the whisker is deflected in this decoupled stimulus space.

PMID: 27348221 [PubMed - as supplied by publisher]

Integration of Telomere Length Dynamics into Systems Biology Framework: A Review.

Gene Regul Syst Bio. 2016;10:35-42

Authors: Nersisyan L

Abstract
Telomere length dynamics plays a crucial role in regulation of cellular processes and cell fate. In contrast to epidemiological studies revealing the association of telomere length with age, age-related diseases, and cancers, the role of telomeres in regulation of transcriptome and epigenome and the role of genomic variations in telomere lengthening are not extensively analyzed. This is explained by the fact that experimental assays for telomere length measurement are resource consuming, and there are very few studies where high-throughput genomics, transcriptomics, and/or epigenomics experiments have been coupled with telomere length measurements. Recent development of computational approaches for assessment of telomere length from whole genome sequencing data pave a new perspective on integration of telomeres into high-throughput systems biology analysis framework. Herein, we review existing methodologies for telomere length measurement and compare them to computational approaches, as well as discuss their applications in large-scale studies on telomere length dynamics.

PMID: 27346946 [PubMed]

Dynamics of calcium spiking, mitochondrial collapse and phosphatidylserine exposure in platelet subpopulations during activation.

J Thromb Haemost. 2016 Jun 25;

Authors: Obydennyy SI, Sveshnikova AN, Ataullakhanov FI, Panteleev MA

Abstract
BACKGROUND: Activated platelets form two subpopulations, one able to efficiently aggregate, while another externalizes phosphatidylserine (PS) and thus accelerates membrane-dependent reactions of blood coagulation. The latter, procoagulant subpopulation is characterized by high cytosolic calcium and loss of inner mitochondrial membrane potential, and there are conflicting opinions on their roles in its formation.
METHODS: We used confocal microscopy to investigate dynamics of subpopulation formation by imaging single, fibrinogen-bound platelets with individual mitochondria in them upon loading with calcium-sensitive and mitochondrial potential-sensitive dyes. Stimulation was with thrombin or protease-activated receptor 1 (PAR1) agonist SFLLRN. Stochastic simulations using computational systems biology model of PAR1 calcium signaling were employed for analysis.
RESULTS: Platelet activation resulted in a series of cytosolic calcium spikes and mitochondrial calcium uptake in all platelets. Frequency of spikes decreased with time for SFLLRN stimulation, but remained high for a long period of time for thrombin. In some platelets, uptake of calcium by mitochondria led to the mitochondrial permeability transition pore opening and inner mitochondrial membrane potential loss that could be either reversible or irreversible. The latter resulted in cytosolic calcium rise and PS exposure. These platelets had higher cytosolic calcium before activation, and their mitochondria collapsed not simultaneously but one after another.
CONCLUSIONS: These results support a model of procoagulant subpopulation development following a series of stochastic cytosolic calcium spikes that are accumulated by mitochondria leading to a collapse, and suggest important roles of individual platelet reactivity and signal exchange between different mitochondria of a platelet. This article is protected by copyright. All rights reserved.

PMID: 27343487 [PubMed - as supplied by publisher]

Prediction of Intra-Species Protein-Protein Interactions in Enteropathogens Facilitating Systems Biology Study.

PLoS One. 2015;10(12):e0145648

Authors: Barman RK, Jana T, Das S, Saha S

Abstract
Protein-protein interactions in Escherichia coli (E. coli) has been studied extensively using high throughput methods such as tandem affinity purification followed by mass spectrometry and yeast two-hybrid method. This can in turn be used to understand the mechanisms of bacterial cellular processes. However, experimental characterization of such huge amount of interactions data is not available for other important enteropathogens. Here, we propose a support vector machine (SVM)-based prediction model using the known PPIs data of E. coli that can be used to predict PPIs in other enteropathogens, such as Vibrio cholerae, Salmonella Typhi, Shigella flexneri and Yersinia entrocolitica. Different features such as domain-domain association (DDA), network topology, and sequence information were used in developing the SVM model. The proposed model using DDA, degree and amino acid composition features has achieved an accuracy of 82% and 62% on 5-fold cross validation and blind E. coli datasets, respectively. The predicted interactions were validated by Gene Ontology (GO) semantic similarity measure and String PPIs database (experimental PPIs only). Finally, we have developed a user-friendly webserver named EnPPIpred to predict intra-species PPIs in enteropathogens, which will be of great help for the experimental biologists. The webserver EnPPIpred is freely available at http://bicresources.jcbose.ac.in/ssaha4/EnPPIpred/.

PMID: 26717407 [PubMed - indexed for MEDLINE]

Transcriptome Analysis of Ullrich Congenital Muscular Dystrophy Fibroblasts Reveals a Disease Extracellular Matrix Signature and Key Molecular Regulators.

PLoS One. 2015;10(12):e0145107

Authors: Paco S, Casserras T, Rodríguez MA, Jou C, Puigdelloses M, Ortez CI, Diaz-Manera J, Gallardo E, Colomer J, Nascimento A, Kalko SG, Jimenez-Mallebrera C

Abstract
BACKGROUND: Collagen VI related myopathies encompass a range of phenotypes with involvement of skeletal muscle, skin and other connective tissues. They represent a severe and relatively common form of congenital disease for which there is no treatment. Collagen VI in skeletal muscle and skin is produced by fibroblasts.
AIMS & METHODS: In order to gain insight into the consequences of collagen VI mutations and identify key disease pathways we performed global gene expression analysis of dermal fibroblasts from patients with Ullrich Congenital Muscular Dystrophy with and without vitamin C treatment. The expression data were integrated using a range of systems biology tools. Results were validated by real-time PCR, western blotting and functional assays.
FINDINGS: We found significant changes in the expression levels of almost 600 genes between collagen VI deficient and control fibroblasts. Highly regulated genes included extracellular matrix components and surface receptors, including integrins, indicating a shift in the interaction between the cell and its environment. This was accompanied by a significant increase in fibroblasts adhesion to laminin. The observed changes in gene expression profiling may be under the control of two miRNAs, miR-30c and miR-181a, which we found elevated in tissue and serum from patients and which could represent novel biomarkers for muscular dystrophy. Finally, the response to vitamin C of collagen VI mutated fibroblasts significantly differed from healthy fibroblasts. Vitamin C treatment was able to revert the expression of some key genes to levels found in control cells raising the possibility of a beneficial effect of vitamin C as a modulator of some of the pathological aspects of collagen VI related diseases.

PMID: 26670220 [PubMed - indexed for MEDLINE]

An omics investigation into chronic widespread musculoskeletal pain reveals epiandrosterone sulfate as a potential biomarker.

Pain. 2015 Oct;156(10):1845-51

Authors: Livshits G, Macgregor AJ, Gieger C, Malkin I, Moayyeri A, Grallert H, Emeny RT, Spector T, Kastenmüller G, Williams FM

Abstract
Chronic widespread musculoskeletal pain (CWP) is common, having a population prevalence of 10%. This study aimed to define the biological basis of the CWP/body mass association by using a systems biology approach. Adult female twins (n = 2444) from the TwinsUK registry who had extensive clinical, anthropometric, and "omic" data were included. Nontargeted metabolomics screening including 324 metabolites was carried out for CWP and body composition using dual-energy X-ray absorptiometry. The biological basis of these associations was explored through a genome-wide association study and replicated in an independent population sample (Cooperative Health Research in the Region of Augsburg [KORA] study, n = 2483). A causal role for the genetic variants identified was sought in CWP using a Mendelian randomisation study design. Fat mass/height2 was the body composition variable most strongly associated with CWP (TwinsUK: P = 2.4 × 10(-15) and KORA: P = 1.59 × 10(-10)). Of 324 metabolites examined, epiandrosterone sulfate (EAS) was highly associated with both CWP (P = 1.05 × 10(-09) in TwinsUK and P = 3.70 × 10(-06) in KORA) and fat mass/height2. Genome-wide association study of EAS identified imputed single nucleotide polymorphism rs1581492 at 7q22.1 to be strikingly associated with EAS levels (P ≤ 2.49 × 10(-78)), and this result was replicated in KORA (P = 2.12 × 10(-9)). Mendelian randomization by rs1581492 genotype showed that EAS is unlikely to be causally related to CWP. Using an agnostic omics approach to focus on the association of CWP with body mass index, we have confirmed a steroid hormone association and identified a genetic variant upstream of the CYP genes, which likely controls this response. This study suggests that steroid hormone abnormalities result from pain rather than causing it, and EAS may provide a biomarker that identifies subgroups at risk of CWP.

PMID: 25915148 [PubMed - indexed for MEDLINE]

Overview of peptide and protein analysis by mass spectrometry.

Curr Protoc Mol Biol. 2014;108:10.21.1-30

Authors: Zhang G, Annan RS, Carr SA, Neubert TA

Abstract
Mass spectrometry is an indispensable tool for peptide and protein analysis owing to its speed, sensitivity, and versatility. It can be used to determine amino acid sequences of peptides, and to characterize a wide variety of post-translational modifications such as phosphorylation and glycosylation. Mass spectrometry can also be used to determine absolute and relative protein quantities, and can identify and quantify thousands of proteins from complex samples, which makes it an extremely powerful tool for systems biology studies. The main goals of this unit are to familiarize peptide and protein chemists and biologists with the types of mass spectrometers that are appropriate for the majority of their analytical needs, to describe the kinds of experiments that can be performed with these instruments on a routine basis, and to discuss the kinds of information that these experiments provide.

PMID: 25271712 [PubMed - indexed for MEDLINE]

Dense Annotation of Free-Text Critical Care Discharge Summaries from an Indian Hospital and Associated Performance of a Clinical NLP Annotator.

J Med Syst. 2016 Aug;40(8):187

Authors: Ramanan SV, Radhakrishna K, Waghmare A, Raj T, Nathan SP, Sreerama SM, Sampath S

Abstract
Electronic Health Record (EHR) use in India is generally poor, and structured clinical information is mostly lacking. This work is the first attempt aimed at evaluating unstructured text mining for extracting relevant clinical information from Indian clinical records. We annotated a corpus of 250 discharge summaries from an Intensive Care Unit (ICU) in India, with markups for diseases, procedures, and lab parameters, their attributes, as well as key demographic information and administrative variables such as patient outcomes. In this process, we have constructed guidelines for an annotation scheme useful to clinicians in the Indian context. We evaluated the performance of an NLP engine, Cocoa, on a cohort of these Indian clinical records. We have produced an annotated corpus of roughly 90 thousand words, which to our knowledge is the first tagged clinical corpus from India. Cocoa was evaluated on a test corpus of 50 documents. The overlap F-scores across the major categories, namely disease/symptoms, procedures, laboratory parameters and outcomes, are 0.856, 0.834, 0.961 and 0.872 respectively. These results are competitive with results from recent shared tasks based on US records. The annotated corpus and associated results from the Cocoa engine indicate that unstructured text mining is a viable method for cohort analysis in the Indian clinical context, where structured EHR records are largely absent.

PMID: 27342107 [PubMed - in process]

The Detection of Emerging Trends Using Wikipedia Traffic Data and Context Networks.

PLoS One. 2015;10(12):e0141892

Authors: Kämpf M, Tessenow E, Kenett DY, Kantelhardt JW

Abstract
Can online media predict new and emerging trends, since there is a relationship between trends in society and their representation in online systems? While several recent studies have used Google Trends as the leading online information source to answer corresponding research questions, we focus on the online encyclopedia Wikipedia often used for deeper topical reading. Wikipedia grants open access to all traffic data and provides lots of additional (semantic) information in a context network besides single keywords. Specifically, we suggest and study context-normalized and time-dependent measures for a topic's importance based on page-view time series of Wikipedia articles in different languages and articles related to them by internal links. As an example, we present a study of the recently emerging Big Data market with a focus on the Hadoop ecosystem, and compare the capabilities of Wikipedia versus Google in predicting its popularity and life cycles. To support further applications, we have developed an open web platform to share results of Wikipedia analytics, providing context-rich and language-independent relevance measures for emerging trends.

PMID: 26720074 [PubMed - indexed for MEDLINE]

9 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results:

("orphan disease" OR "rare disease" OR "orphan diseases" OR "rare diseases")

These pubmed results were generated on 2016/06/25

PubMed comprises more than 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

Pathway and network-based strategies to translate genetic discoveries into effective therapies.

Hum Mol Genet. 2016 Jun 23;

Authors: Greene CS, Voight BF

Abstract
One way to design a drug is to attempt to phenocopy a genetic variant that is known to have the desired effect. In general, drugs that are supported by genetic associations progress further in the development pipeline. However, the number of associations that are candidates for development into drugs is limited because many associations are in noncoding regions or difficult to target genes. Approaches that overlay information from pathway databases or biological networks can expand the potential target list. In cases where the initial variant is not targetable or there is no variant with the desired effect, this may reveal new means to target a disease. In this review we discuss recent examples in the domain of pathway and networkbased drug repositioning from genetic associations. We highlight important caveats and challenges for the field, and we discuss opportunities for further development.

PMID: 27340225 [PubMed - as supplied by publisher]

The anthelmintic niclosamide inhibits colorectal cancer cell lines via modulation of the canonical and noncanonical Wnt signaling pathway.

J Surg Res. 2016 Jun 1;203(1):193-205

Authors: Monin MB, Krause P, Stelling R, Bocuk D, Niebert S, Klemm F, Pukrop T, Koenig S

Abstract
BACKGROUND: Wnt/β-catenin signaling is known to play an important role in colorectal cancer (CRC). Niclosamide, a salicylamide derivative used in the treatment of tapeworm infections, targets the Wnt/β-catenin pathway. The objective of this study was to investigate niclosamide as a therapeutic agent against CRC.
METHODS: The antiproliferative effects of 1, 3, 10, and 50 μM concentrations of niclosamide on human (SW480 and SW620) and rodent (CC531) CRC cell lines were determined by MTS assay and direct cell count. The lymphoid enhancer-binding factor 1/transcription factor (LEF/TCF) reporter assay monitored the activity of Wnt signaling. Immunofluorescence staining demonstrated the expression pattern of active β-catenin. Gene expression of canonical and noncanonical Wnt signaling components was analyzed using qRT-PCR. Western blot analysis was performed with antibodies detecting nuclear localization of β-catenin and c-jun.
RESULTS: Cell proliferation in CRC cell lines was blocked dose dependently after 12 and 24 h of incubation. The Wnt promoter activity of LEF/TCF significantly decreased with niclosamide concentrations of 10 and 50 μM after 12 h of incubation. Active β-catenin did not shift from the nuclear to the cytosolic pool. However, canonical target genes (met, MMP7, and cyclin D1) as well as the coactivating factor Bcl9 were downregulated, whereas the noncanonical key player c-jun was clearly activated.
CONCLUSIONS: Niclosamide treatment is associated with an inhibitory effect on CRC development and reduced Wnt activity. It may exert its effect by interfering with the nuclear β-catenin-Bcl9-LEF/TCF triple-complex and by upregulation of c-jun representing noncanonical Wnt/JNK signaling. Thus, our findings warrant further research into this substance as a treatment option for patients with advanced CRC.

PMID: 27338550 [PubMed - in process]