Expression Of Cell Adhesion Proteins Research Articles

Vitamin A Status Modulates Epithelial Mesenchymal Transition in the Lung: The Role of Furin.

Vitamin A deficiency (VAD) induced TGF-β hyperactivation and reduced expression of cell adhesion proteins in the lung, suggesting that the disruption of retinoic acid (RA) signaling leads to epithelial-mesenchymal transition (EMT). To elucidate the role of lung vitamin A status in EMT, several EMT markers and the expression of the proprotein convertase furin, which activates TGF-β, were analyzed in two experimental models. Our in vivo model included control rats, VAD rats, and both control rats and VAD rats, treated with RA. For the in vitro studies, human bronchoalveolar epithelial cells treated with RA were used. Our data show that EMT and furin are induced in VAD rats. Furthermore, furin expression continues to increase much more markedly after treatment of VAD rats with RA. In control rats and cell lines, an acute RA treatment induced a significant increase in furin expression, concomitant with changes in EMT markers. A ChIP assay demonstrated that RA directly regulates furin transcription. These results emphasize the importance of maintaining vitamin A levels within the physiological range since both levels below and above this range can cause adverse effects that, paradoxically, could be similar. The role of furin in EMT is discussed.

The suppression of cell motility through the reduction of FAK activity and expression of cell adhesion proteins by hAMSCs secretome in MDA-MB-231 breast cancer cells.

Breast cancer is a leading cause of death in women worldwide. Cancer therapy based on stem cells is considered as a novel and promising platform. In the present study, we explore the therapeutic effects of human amniotic mesenchymal stromal cells (hAMSCs) through the reduction of focal adhesion kinase (FAK) activity, SHP-2, and cell adhesion proteins such as Paxillin, Vinculin, Fibronectin, Talin, and integrin αvβ3 expression in MDA-MB-231 breast cancer cells. For this purpose, we employed a co-culture system using 6-well plate transwell. After 72h, hAMSCs-treated MDA-MB-231 breast cancer cells, the activity of focal adhesion kinase (FAK) and the expression of SHP-2 and cell adhesion proteins such as Paxillin, Vinculin, Fibronectin, Talin, and integrin αvβ3 expression were analyzed using western blot. The shape and migration of cells were also analyzed. Based on our results, a significant reduction in tumor cell motility through downregulation of the tyrosine phosphorylation level of FAK (at Y397 and Y576/577 sites) and cell adhesion expression in MDA-MB-231 breast cancer cells was demonstrated. Our findings indicate that hAMSCS secretome has therapeutic effects on cancer cell migration through downregulation of FAK activity and expression of cell adhesion proteins.

Cell adhesion marker expression dynamics during fusion of the optic fissure

Tissue fusion is a critical process that is repeated in multiple contexts during embryonic development and shares common attributes to processes such as wound healing and metastasis. Ocular coloboma is a developmental eye disorder that presents as a physical gap in the ventral eye, and is a major cause of childhood blindness. Coloboma results from fusion failure between opposing ventral retinal epithelia, but there are major knowledge gaps in our understanding of this process at the molecular and cell behavioural levels. Here we catalogue the expression of cell adhesion proteins: N-cadherin, E-cadherin, R-cadherin, ZO-1, and the EMT transcriptional activator and cadherin regulator SNAI2, in the developing chicken embryonic eye. We find that fusion pioneer cells at the edges of the fusing optic fissure have unique and dynamic expression profiles for N-cad, E-cad and ZO-1, and that these are temporally preceded by expression of SNAI2. This highlights the unique properties of these cells and indicates that regulation of cell adhesion factors may be a critical process in optic fissure closure.

Analysis of cnidarian Gcm suggests a neuronal origin of glial EAAT1 function

In bilaterian central nervous systems, coordination of neurotransmission by glial cells enables highly sophisticated neural functions. The diversity of transcription factors (TFs) involved in gliogenesis suggests multiple evolutionary origins of various glial cell types of bilaterians. Many of these TFs including the glial cells missing (Gcm) are also present in genomes of Cnidaria, the closest outgroup to Bilateria, but their function remains to be elucidated. In this study, we analyzed the function of Gcm, a multifunctional TF involved in development of glial and non-glial cell types, in the sea anemone, Nematostella vectensis. siRNA-mediated knockdown of Nematostella Gcm altered expression of cell adhesion proteins, glutamate and GABA transporters, ion channels, metabolic enzymes, and zinc finger and Ets-related TFs. NvGcm and mRNAs of downstream genes are expressed in broad neural cell clusters. However, immunostaining of a NvGcm target protein, the glutamate transporter, NvEAAT1, visualized a novel class of cells with flat cell bodies and no clear processes. Together with the finding of unique morphological features of NvEAAT1-functioning cells, these data suggest that extracellular glutamate metabolism, one of major glial functions, is deployed downstream of Gcm in specific neural cell types in Cnidaria.

Development of a Human Respiratory Mucosa-on-a-chip using Decellularized Extracellular Matrix

The airway mucosa is the first point of exposure to all inhalant materials. It is possible to produce microenvironments functionally similar to airway by using different types of extracellular matrices around mucosal cells, such as an extracellular matrix decellularized from trachea. In this study, we introduced a novel human respiratory mucosa-on-a-chip model that uses decellularized tracheal extracellular matrix to assess functional similarities. We also evaluated the effects of respiratory toxicant based on changes in cell viability, tight junction function, oxidative stress, expression of cell adhesion proteins in the vascular network, mucous secretion, and inflammatory cytokine secretion after treatment. This novel human respiratory mucosa-on-a-chip model is expected to be useful for assessing respiratory mucosa reactions to external bacteria or viruses and inhaled drugs.

Immunodetection of Epithelial-Mesenchymal Transition and Tumor Proliferation Markers in GLi-1-positive Oral Squamous Cell Carcinoma.

In oral squamous cell carcinoma (OSCC), involvement and activation of the Hedgehog pathway (HH) may be related to epithelial-mesenchymal transition and cell proliferation. The present study aimed to evaluate epithelial-mesenchymal transition and proliferative potential in OSCC cases demonstrating activation of the HH pathway. Twenty-three GLi-1-positive OSCC cases were submitted to immunohistochemical detection of Snail, Slug, N-cadherin, E-cadherin, β-catenin, and MCM3 proteins. Clinical-pathologic immunoexpression data were obtained from the invasion front and tumor islets, and then compared. At the invasion front, OSCC cases presented positive Snail, Slug, and MCM3 expression in the nuclei of tumor cells. Loss of membrane and cytoplasmic expression of E-cadherin and β-catenin was also observed. Positive N-cadherin expression was observed in 31.78% of the cases. GLi-1 immunoexpression was associated with loss of membrane E-cadherin (P<0.001), membrane β-catenin (P<0.001), and cytoplasmic β-catenin (P=0.02) expression. In the tumor islets, we observed nuclear expression of GLi-1, Snail, Slug, and MCM3. E-cadherin and β-catenin showed positivity in tumor cell membranes. Statistically significant positive correlations between GLi-1 and Snail (P=0.05), E-cadherin (P=0.01), and cytoplasmic β-catenin (P=0.04) were found. GLi-1 was associated with clinical staging, while membrane β-catenin expression was related to the presence of metastasis in lymph nodes and to clinical staging. The HH pathway may be involved in regulating the expression of the mesenchymal phenotype. The loss of membrane E-cadherin and β-catenin expression was observed at the tumor front region, whereas cell adhesion protein expression was detected in tumor islets regardless of MCM3.

Histone deacetylase inhibitors dysregulate DNA repair proteins and antagonize metastasis-associated processes

PurposeWe set out to determine whether clinically tested epigenetic drugs against class I histone deacetylases (HDACs) affect hallmarks of the metastatic process.MethodsWe treated permanent and primary renal, lung, and breast cancer cells with the class I histone deacetylase inhibitors (HDACi) entinostat (MS-275) and valproic acid (VPA), the replicative stress inducer hydroxyurea (HU), the DNA-damaging agent cis-platinum (L-OHP), and the cytokine transforming growth factor-β (TGFβ). We used proteomics, quantitative PCR, immunoblot, single cell DNA damage assays, and flow cytometry to analyze cell fate after drug exposure.ResultsWe show that HDACi interfere with DNA repair protein expression and trigger DNA damage and apoptosis alone and in combination with established chemotherapeutics. Furthermore, HDACi disrupt the balance of cell adhesion protein expression and abrogate TGFβ-induced cellular plasticity of transformed cells.ConclusionHDACi suppress the epithelial–mesenchymal transition (EMT) and compromise the DNA integrity of cancer cells. These data encourage further testing of HDACi against tumor cells.

Endothelial intercellular cell adhesion molecule 1 contributes to cell aggregate formation in CHO cells cultured in serum-free media.

Chinese hamster ovary (CHO) cells have been adapted to grow in serum-free media and in suspension culture to facilitate manufacturing needs. Some CHO cell lines, however, tend to form cell aggregates while being cultured in suspension. This can result in reduced viability and capacity for single cell cloning (SCC) via limiting dilution, and process steps to mitigate cell aggregate formation, for example, addition of anti-cell-aggregation agents. In this study, we have identified endothelial intercellular cell adhesion molecule 1 (ICAM-1) as a key protein promoting cell aggregate formation in a production competent CHO cell line, which is prone to cell aggregate formation. Knocking out (KO) the ICAM-1 gene significantly decreased cell aggregate formation in the culture media without anti-cell-aggregation reagent. This trait can simplify the process of transfection, selection, automated clone isolation, and so on. Evaluation in standard cell line development of ICAM-1 KO and wild-type CHO hosts did not reveal any noticeable impacts on titer or product quality. Furthermore, analysis of a derived nonaggregating cell line showed significant reductions in expression of cell adhesion proteins. Overall, our data suggest that deletion of ICAM-1 and perhaps other cell adhesion proteins can reduce cell aggregate formation and improve clonality assurance during SCC.

Inositol polyphosphate multikinase is a metformin target that regulates cell migration.

Metformin has been shown to alter cell adhesion protein expression, which is thought to play a role in its observed antitumor properties. We found that metformin treatment down-regulated integrin β1 concomitant with the loss of inositol polyphosphate multikinase (IPMK) in murine myocytes, adipocytes, and hepatocytes. To determine if IPMK was upstream of integrin β1 expression, we examined IPMK-/- mouse embryonic fibroblast cells and found that integrins β1 and β3 gene expression was reduced by half, relative to wild-type cells, whereas focal adhesion kinase (FAK) activity and Rho/Rac/Cdc42 protein levels were increased, resulting in migration defects. Using nanonet force microscopy, we determined that cell:extracellular matrix adhesion and cell contractility forces were decreased, confirming the functional relevance of integrin and Rho protein dysregulation. Pharmacological studies showed that inhibition of both FAK1 and proline-rich tyrosine kinase 2 partially restored integrin β1 expression, suggesting negative regulation of integrin β1 by FAK. Together our data indicate that IPMK participates in the regulation of cell migration and provides a potential link between metformin and wound healing impairment.-Tu-Sekine, B., Padhi, A., Jin, S., Kalyan, S., Singh, K., Apperson, M., Kapania, R., Hur, S. C., Nain, A., Kim, S. F. Inositol polyphosphate multikinase is a metformin target that regulates cell migration.

Low glucose availability alters the expression of genes involved in initial adhesion of human glioblastoma cancer cell line SF767.

Studying the metabolic pathways of cancer cells is considered as a key to control cancer malignancies and open windows for effective drug discovery against cancer. Of all the properties of a tumor, metastasis potential is a defining characteristic. Metastasis is controlled by a variety of factors that directly control the expression of cell adhesion proteins. In this study we have investigated the expression of cell to cell and cell to matrix adhesion protein genes during the initial phases of attachment of human glioblastoma cancer cell line SF767 (66Y old human female: UCSF Neurosurgery Tissue Bank) to the attachment surface under (Cell culture treated polystyrene plate bottom) glucose-rich and glucose-starved conditions. The aim was to imitate the natural microenvironment of glucose availability to cancer cells inside a tumor that triggers epithelial to mesenchymal transition (EMT). In this study, we have observed the gene expression of epithelial and mesenchymal isoforms of cadherin (E-CAD and N-CAD) and Ig like cell adhesion molecules (E-CAM and N-CAM) along with Integrin family subunits for the initial attachment of cancer cells. We observed that high glucose environments promoted cell survival and cell adhesion, whereas low glucose accelerated EMT by downregulating the expression level of integrin, E-CAD, and N-CAD, and upregulation of N-CAM during early period of cell adhesion. Low glucose availability also downregulated variety of structural and regulatory genes, such as zinc finger E-box binding home box 1A), cytokeratin, Snail, and β catenin, and upregulation of hypoxia-inducible factor 1, matrix metalloprotease 13/Collagenase 3, vimentim, p120, and fructose 1,6 bisphosphatase. Glucose conditions are more efficient for cancer studies in this case glioblastoma cells.

Effect of plasma-nitrided titanium surfaces on the differentiation of pre-osteoblastic cells.

A titanium surface nitrided by plasma contains nitrogen ions that guarantee resistance to corrosion and biocompatibility. Despite this, no descriptions concerning the influence of the expression of cell adhesion proteins and their influence on osteogenic cell differentiation are available. Thus, the present study aimed to assess the response of murine pre-osteoblastic cells (MC3T3-E1) cultured on nitrided titanium surfaces. Pre-osteoblastic cells were grown on polished titanium discs, used as controls, and on previously characterized plasma-nitrided titanium discs. Cells from both groups were submitted to the MTT cell viability test. The expressions of α5, α2, and β1 integrin were assessed by flow cytometry and immunofluorescence, while osteocalcin expression was assessed by flow cytometry. The nitrided surface presented higher α2 and β1 integrin expressions, as well as osteocalcin expression, when compared to the polished surface, with no alterations in cell viability. These findings seem to suggest that the plasma nitriding treatment produces a titanium surface with the potential for effective in vitro osseointegration.

Mimicking brain tumor-vasculature microanatomical architecture via co-culture of brain tumor and endothelial cells in 3D hydrogels

Glioblastoma (GBM) is an aggressive malignant brain tumor with median survival of 12 months and 5-year survival rate less than 5%. GBM is highly vascularized, and the interactions between tumor and endothelial cells play an important role in driving tumor growth. To study tumor-endothelial interactions, the gold standard co-culture model is transwell culture, which fails to recapitulate the biochemical or physical cues found in tumor niche. Recently, we reported the development of poly(ethylene-glycol)-based hydrogels as 3D niche that supported GBM proliferation and invasion. To further mimic the microanatomical architecture of tumor-endothelial interactions in vivo, here we developed a hydrogel-based co-culture model that mimics the spatial organization of tumor and endothelial cells. To increase the physiological relevance, patient-derived GBM cells and mouse brain endothelial cells were used as model cell types. Using hydrolytically-degradable alginate fibers as porogens, endothelial cells were deployed and patterned into vessel-like structures in 3D hydrogels with high cell viability and retention of endothelial phenotype. Co-culture led to a significant increase in GBM cell proliferation and decrease in endothelial cell expression of cell adhesion proteins. In summary, we have developed a novel 3D co-culture model that mimics the in vivo spatial organization of brain tumor and endothelial cells. Such model may provide a valuable tool for future mechanistic studies to elucidate the effects of tumor-endothelial interactions on tumor progression in a more physiologically-relevant manner.

Abstract A066: Expanding insights into the colorectal cancer tumor proteome; unbiased protein profiling reveals multiple proteomic-based tumor subtypes

Abstract Introduction: Recent approvals of microsatellite instability (MSI) or mismatch repair (MMR) testing, in addition to PD-L1 expression, expand the tools available to identify tumor characteristics that may help predict the likelihood of patient response to immunotherapy treatment. However, even in MSI positive subgroups, not all subjects achieve a durable response and research continues to identify tumor characteristics that further predict the likelihood of patient response. To support and advance this area of research, new tools are being developed that provide deeper and unbiased views of the tumor proteome. Here, we characterize the protein expression profiles of 95 colorectal cancer tumors (CRC) using SWATH acquisition mass spectrometry (SWATH MS) to further probe tumor phenotypic characteristics. Experimental Methods: FFPE colon tissue samples (10 healthy, 95 cancer) were obtained from commercial biobanks. Proteins were extracted from the tissue, processed to peptides with trypsin, and prepared for LC-MS analysis. Peptides for each sample were injected on a Triart C18 column (YMC) coupled to a NanoLC 425 system (SCIEX) using a 43min gradient at a flow rate of 5µl/min. The eluted peptides were then analyzed with a TripleTOF® 6600 system (SCIEX) operated in SWATH mode. Total run time per sample was 1 hour. Data were analyzed in Spectronaut Pulsar X (Biognosys) with a project specific library. All data were filtered with a 1% FDR on peptide and protein level. Results: Across all samples, &amp;gt;4,500 protein groups were quantified (approximately 3,600 per sample). Data analysis revealed a large number of proteins (~1,000) were differentially expressed in the cancer cohort. Consistent with increased tumor cell proliferation, proteins involved in protein translation were upregulated in the tumor samples. Unsupervised clustering of the data separated the healthy and the cancer cohort. Clustering also revealed three main proteomic subtypes within in the cancer cohort (A, B and C), which were largely distinguished by expression of cell adhesion proteins, including neuronal growth regulator 1 (NEGR1), a potential tumor suppressor. Interestingly, hepatocyte nuclear factor 4-alpha (HNF4A), a transcription factor which is known to be elevated in CRC, was only overexpressed in subtype B. Further analysis of key protein networks related to CRC treatment and immunotherapy development will be presented. Conclusions: High-throughput proteomic profiling of FFPE tissues using SWATH-MS enables the deepest phenotypic characterization of tumor tissue. Ultimately, analyses of this type will enable a functional understanding of interplay between the tumor microenvironment, expression of protein networks and response to immune-directed therapies. Citation Format: Nicholas Dupuis, Jan Muntel, Roland Bruderer, Lukas Reiter. Expanding insights into the colorectal cancer tumor proteome; unbiased protein profiling reveals multiple proteomic-based tumor subtypes [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A066.

Inducible Loss Of Integrin β1 From Bladder Smooth Muscle Causes Increased Voiding Frequency And Impaired Muscarinic Contractility

Integrins are integral membrane proteins which, in dynamic ways, physically link, the actin cytoskeleton to the extracellular matrix. They exhibit broad functional diversity and are involved in cellular differentiation, adhesion, proliferation and mechanotransduction. Diabetic bladder dysfunction (DBD) is a very common progressive complication of diabetes mellitus resulting in overactivity during the early compensatory phase and ultimately in an atonic bladder which is unable to empty properly. Both genomic and proteomic approaches focused on bladder smooth muscle (BSM) have demonstrated altered expression of cell adhesion proteins and extracellular matrix as well as compromised contractility, as molecular markers of DBD. To begin to understand the role of cell adhesion and mechanosensitive signaling in BSM we created a mouse with tamoxifen (TMX) inducible, smooth muscle‐conditional deletion of β1‐integrin using Cre‐lox (Txβ1‐cKO). Loss of β1‐integrin mRNA and protein following TMX induction by i.p. injection (5 × 2 mg on consecutive days) were confirmed by PCR and Western blotting. Void‐spotting assays on filter paper revealed a progressive increase in number of voids from 2.5/4 h to 8.3/4 h over a period of 60 days following Cre‐induction (n=5 mice/group, P&lt;0.05). Littermate controls injected with vehicle (no TMX) showed no change. The mean volume/void decreased from 264 μl to 158 μl over 60 days in the integrin knockouts. An increase in the number of voids with reduced volume/void is often taken to indicate some form of overactivity. Urodynamic measurements using cystometry under anesthesia, revealed significantly reduced peak bladder pressures during voiding (20 cmH2O vs. 26 cmH2O, P&lt;0.05), reduced intercontraction interval (44 s vs. 249 s, P&lt;0.01), and reduced compliance (17 s/cmH2O vs. 68 s/cmH2O, N.S.) in TMX injected vs. control mice. Thus, in vivo voiding frequency was dramatically increased at the same time as the bladders showed increased resistance to filling and lower expulsive pressures. Urothelium dissected muscle‐strip force measurements by myography revealed a significant loss of contractile force in integrin‐deficient bladders in response to electrical field stimulation (45% and 62% mean reductions at 25 and 60 days post Cre‐induction respectively, for stimulation frequencies of 1 – 50 Hz). Selective inhibition of the muscarinic force component by incubation of strips with 0.5 μM atropine, indicated that muscarinic contractility was severely inhibited in integrin‐deficient BSM (17.2% of force generation was due to muscarinic receptors compared to 50% in controls) while purinergic contractility was largely intact. Masson trichrome staining of paraffin embedded bladder sections revealed a substantial expansion of collagenous connective tissue in BSM and disruption to close packing of smooth muscle bundles. We conclude that β1‐integrin is necessary for BSM structural integrity and for muscarinic signaling during force generation. These findings begin to offer insights into the physiological role of integrin mechanical signaling in BSM and may be relevant to certain bladder pathologies in which integrin expression levels have been shown to be dysregulated.Support or Funding InformationSupport for this work was provided by NIH grants DK‐083299 and DK‐095922.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Inhibition of PTP1B disrupts cell\u2013cell adhesion and induces anoikis in breast epithelial cells

Protein tyrosine phosphatase 1B (PTP1B) is a well-known inhibitor of insulin signaling pathways and inhibitors against PTP1B are being developed as promising drug candidates for treatment of obesity. PTP1B has also been linked to breast cancer both as a tumor suppressor and as an oncogene. Furthermore, PTP1B has been shown to be a regulator of cell adhesion and migration in normal and cancer cells. In this study, we analyzed the PTP1B expression in normal breast tissue, primary breast cells and the breast epithelial cell line D492. In normal breast tissue and primary breast cells, PTP1B is widely expressed in both epithelial and stromal cells, with highest expression in myoepithelial cells and fibroblasts. PTP1B is widely expressed in branching structures generated by D492 when cultured in 3D reconstituted basement membrane (3D rBM). Inhibition of PTP1B in D492 and another mammary epithelial cell line HMLE resulted in reduced cell proliferation and induction of anoikis. These changes were seen when cells were cultured both in monolayer and in 3D rBM. PTP1B inhibition affected cell attachment, expression of cell adhesion proteins and actin polymerization. Moreover, epithelial to mesenchymal transition (EMT) sensitized cells to PTP1B inhibition. A mesenchymal sublines of D492 and HMLE (D492M and HMLEmes) were more sensitive to PTP1B inhibition than D492 and HMLE. Reversion of D492M to an epithelial state using miR-200c-141 restored resistance to detachment induced by PTP1B inhibition. In conclusion, we have shown that PTP1B is widely expressed in the human breast gland with highest expression in myoepithelial cells and fibroblasts. Inhibition of PTP1B in D492 and HMLE affects cell–cell adhesion and induces anoikis-like effects. Finally, cells with an EMT phenotype are more sensitive to PTP1B inhibitors making PTP1B a potential candidate for further studies as a target for drug development in cancer involving the EMT phenotype.

Abstract 1009: Cytotoxic effect of ginsenosides C-K and PPD on glioblastoma cells through cell cycle arrest and down-regulation of cell adhesion proteins

Abstract Ginsenosides, pharmacologically active components of ginseng have been shown to have strong anticancer effects; however, their effect on glioblastoma has not been extensively evaluated. Here, we investigated the anticancer effect and the molecular mechanisms of ginsenosides on glioblastoma. Among 12 ginsenosides tested, compound-K (C-K) and protopanaxadiol (PPD), significantly reduced U251MG cell viability in dose- and time-dependent manner. This cytotoxic effect was accompanied by decreased expression of cell adhesion proteins including N-Cadherin and Integrin β1, which led to reduced phosphorylation of focal adhesion kinase. Furthermore, we observed the reduction of Cyclin D1 and subsequent G1-phase cell cycle arrest. We further demonstrated that C-K and PPD inhibited the phosphorylation of Akt and extracellular signal regulated kinase. Conversely, C-K and PPD stimulated phosphorylation of JNK and cleavage of PARP. These results collectively indicate that ginsenosides C-K and PPD may provide a new strategy to treat malignant glioblastoma that are quite resistant to conventional anti-cancer treatment. (This research was supported by a grant of the Korea Health Technology R&amp;D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health &amp; Welfare, Republic of Korea;grant number : HI14C0042) Citation Format: Eunsoo Kim, Cheryl Wanderi, Chulhee Choi, Kyungsun Choi. Cytotoxic effect of ginsenosides C-K and PPD on glioblastoma cells through cell cycle arrest and down-regulation of cell adhesion proteins. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1009. doi:10.1158/1538-7445.AM2015-1009

EGFR expression in pancreatic adenocarcinoma. Relationship to tumour morphology and cell adhesion proteins

AimsWe aimed to study epidermal growth factor receptor (EGFR) expression in surgically resected pancreatic ductal adenocarcinomas (PDACs) by immunohistochemistry and their relationship to clinicopathological features, cell proliferation and cell adhesion...

14 EMERGING VASCULAR TARGETS

Endothelial dysfunction, characterized as a pro-coagulative, pro-inflammatory, secretory and vasoconstrictory phenotype, is an early event in many chronic diseases that frequently precedes cardiovascular complications. Associated with these processes is formation of microparticles, which are anuclear fragments of cellular membrane shed from stressed or damaged cells. Microparticles contain surface proteins and cytoplasmic content of the parental cells and have been identified as biomarkers of endothelial dysfunction in many cardiovascular diseases. However recent evidence indicates that microparticles themselves exert injurious endothelial effects. This is evidenced by our recent studies demonstrating that microparticles 1) interact physically with endothelial cells, 2) stimulate oxidative stress and expression of cell adhesion proteins in endothelial cells, 3) promote a phenotype of senescence and 4) directly modulate vascular contraction/relaxation. Exact mechanisms for this cross-talk between microparticles and endothelial cells are unclear, although reactive oxygen species, lipid rafts and RhoA/Rho kinase may play a role. Accordingly in addition to reflecting endothelial stress/damage, microparticles may themselves have biological activity and contribute to vascular dysfunction. Such processes might occur through a feed-forward system where endothelial cell injury leads to microparticle formation, which in turn interacts with endothelial cells to stimulate pro-inflammatory and vasoconstrictor signaling to amplify endothelial dysfunction. This paradigm identifies putative novel vascular targets that may both reflect and contribute to vascular dysregulation.

Enhancement of neurite outgrowth in PC12 cells by iron oxide nanoparticles

Despite the many potential therapeutic applications of iron oxide nanoparticle such as its use as an imaging and targeting tool, its biological effects have not yet been extensively characterized. Herein, we report that iron oxide nanoparticles taken up by PC12 cells can enhance neurite outgrowth. PC12 cells exposed to both iron oxide nanoparticles and nerve growth factor (NGF) synergistically increased the efficiency of neurite outgrowth in a dose-dependent manner. This may have resulted from the activation of cell adhesion molecules that are associated with cell–matrix interactions through iron. Immunoblotting assays also revealed that both neural specific marker protein and cell adhesion protein expression were upregulated by iron oxide nanoparticles compared with non-treated cells via activation of the mitogen-activated protein kinase (MAPK) signaling pathway. Our findings point to the possibility that iron oxide nanoparticles can affect cell–substrate interactions and regulate cell behaviors, which provides clinical insights into potential neurologic and therapeutic applications of iron oxide nanoparticles.

Pulmonary exposure to carbon black nanoparticles and vascular effects

BackgroundExposure to small size particulates is regarded as a risk factor for cardiovascular diseases.MethodsWe exposed young and aged apolipoprotein E knockout mice (apoE-/-) to carbon black (Printex 90, 14 nm) by intratracheal instillation, with different dosing and timing, and measured vasomotor function, progression of atherosclerotic plaques, and VCAM-1, ICAM-1, and 3-nitrotyrosine in blood vessels. The mRNA expression of VCAM-1, ICAM-1, HO-1, and MCP-1 was examined in lung tissue.ResultsYoung apoE-/- mice exposed to two consecutive 0.5 mg/kg doses of carbon black exhibited lower acetylcholine-induced vasorelaxation in aorta segments mounted in myographs, whereas single doses of 0.05-2.7 mg/kg produced no such effects. The phenylephrine-dependent vasocontraction response was shifted toward a lower responsiveness in the mice exposed once to a low dose for 24 hours. No effects were seen on the progression of atherosclerotic plaques in the aged apoE-/- mice or on the expression of VCAM-1 and ICAM-1 and the presence of 3-nitrotyrosine in the vascular tissue of either young or aged apoE-/- mice. The expression of MCP-1 mRNA was increased in the lungs of young apoE-/- mice exposed to 0.9-2.7 mg/kg carbon black for 24 hours and of aged apoE-/- mice exposed to two consecutive 0.5 mg/kg doses of carbon black seven and five weeks prior to sacrifice.ConclusionExposure to nano-sized carbon black particles is associated with modest vasomotor impairment, which is associated neither with nitrosative stress nor with any obvious increases in the expression of cell adhesion proteins on endothelial cells or in plaque progression. Evidence of pulmonary inflammation was observed, but only in animals exposed to higher doses.