Cell Adhesion Processes Research Articles

Grapevine phenolic compounds influence cell surface adhesion of Xylella fastidiosa and bind to lipopolysaccharide.

Bacterial phytopathogen Xylella fastidiosa specifically colonizes the plant vascular tissue through a complex process of cell adhesion, biofilm formation, and dispersive movement. Adaptation to the chemical environment of the xylem is essential for bacterial growth and progression of infection. Grapevine xylem sap contains a range of plant secondary metabolites such as phenolics, which fluctuate in response to pathogen infection and plant physiological state. Phenolic compounds are often involved in host-pathogen interactions and influence infection dynamics through signaling activity, antimicrobial properties, and alteration of bacterial phenotypes. The effect of biologically relevant concentrations of phenolic compounds coumaric acid, gallic acid, epicatechin, and resveratrol on growth of X. fastidiosa was assessed in vitro. None of these compounds inhibited bacterial growth, but epicatechin and gallic acid reduced cell-surface adhesion. Cell-cell aggregation decreased with resveratrol treatment, but the other phenolic compounds tested had minimal effect on aggregation. Expression of attachment (xadA) and aggregation (fimA) related genes were altered by presence of the phenolic compounds, consistent with observed phenotypes. All four of the phenolic compounds bound to purified X. fastidiosa lipopolysaccharide (LPS), a major cell-surface component. Information regarding the impact of chemical environment on pathogen colonization in plants is important for understanding the infection process and factors associated with host susceptibility.

LncRNA Profiling Reveals That the Deregulation of H19, WT1-AS, TCL6, and LEF1-AS1 Is Associated with Higher-Risk Myelodysplastic Syndrome.

Simple SummaryAlthough lncRNAs have been increasingly recognized as regulators of hematopoiesis, only several studies addressed their role in myelodysplastic syndrome (MDS). By genome-wide profiling, we identified lncRNAs deregulated in various groups of MDS patients. We computationally constructed lncRNA-protein coding gene networks to associate deregulated lncRNAs with cellular processes involved in MDS. We showed that expression of H19, WT1-AS, TCL6, and LEF1-AS1 lncRNAs associate with higher-risk MDS and proposed processes related with these transcripts.Background: myelodysplastic syndrome (MDS) is a hematopoietic stem cell disorder with an incompletely known pathogenesis. Long noncoding RNAs (lncRNAs) play multiple roles in hematopoiesis and represent a new class of biomarkers and therapeutic targets, but information on their roles in MDS is limited. Aims: here, we aimed to characterize lncRNAs deregulated in MDS that may function in disease pathogenesis. In particular, we focused on the identification of lncRNAs that could serve as novel potential biomarkers of adverse outcomes in MDS. Methods: we performed microarray expression profiling of lncRNAs and protein-coding genes (PCGs) in the CD34+ bone marrow cells of MDS patients. Expression profiles were analyzed in relation to different aspects of the disease (i.e., diagnosis, disease subtypes, cytogenetic and mutational aberrations, and risk of progression). LncRNA-PCG networks were constructed to link deregulated lncRNAs with regulatory mechanisms associated with MDS. Results: we found several lncRNAs strongly associated with disease pathogenesis (e.g., H19, WT1-AS, TCL6, LEF1-AS1, EPB41L4A-AS1, PVT1, GAS5, and ZFAS1). Of these, downregulation of LEF1-AS1 and TCL6 and upregulation of H19 and WT1-AS were associated with adverse outcomes in MDS patients. Multivariate analysis revealed that the predominant variables predictive of survival are blast count, H19 level, and TP53 mutation. Coexpression network data suggested that prognosis-related lncRNAs are predominantly related to cell adhesion and differentiation processes (H19 and WT1-AS) and mechanisms such as chromatin modification, cytokine response, and cell proliferation and death (LEF1-AS1 and TCL6). In addition, we observed that transcriptional regulation in the H19/IGF2 region is disrupted in higher-risk MDS, and discordant expression in this locus is associated with worse outcomes. Conclusions: we identified specific lncRNAs contributing to MDS pathogenesis and proposed cellular processes associated with these transcripts. Of the lncRNAs associated with patient prognosis, the level of H19 transcript might serve as a robust marker comparable to the clinical variables currently used for patient stratification.

Inhibition of orf virus replication in goat skin fibroblast cells by the HSPA1B protein, as demonstrated by iTRAQ-based quantitative proteome analysis.

Orf virus (ORFV) infects sheep and goat tissues, resulting in severe proliferative lesions. To analyze cellular protein expression in ORFV-infected goat skin fibroblast (GSF) cells, we used two-dimensional liquid chromatography-tandem mass spectrometry coupled with isobaric tags for relative and absolute quantification (iTRAQ). The proteomics approach was used along with quantitative reverse transcription polymerase chain reaction (RT-qPCR) to detect differentially expressed proteins in ORFV-infected GSF cells and mock-infected GSF cells. A total of 282 differentially expressed proteins were identified. It was found that 222 host proteins were upregulated and 60 were downregulated following viral infection. We confirmed that these proteins were differentially expressed and found that heat shock 70-kDa protein 1B (HSPA1B) was differentially expressed and localized in the cytoplasm. It was also noted that HSPA1B caused inhibition of viral proliferation, in the middle and late stages of viral infection. The differentially expressed proteins were associated with the biological processes of viral binding, cell structure, signal transduction, cell adhesion, and cell proliferation.

Fabrication of porous films from immiscible polymer blends: Role of the surface structure on the cell adhesion

We report the preparation of microporous surfaces prepared from immiscible polymer blends using the Breath Figures methodology. The selected polymer blend is formed by two biodegradable polymers i.e. poly(ε-caprolactone) and poly(lactic acid) both known to be biocompatible and presenting two distinct kinetics of biodegradation. These two polymers form immiscible polymer blends upon solvent casting in low relative humidity conditions. However, when quenching the melt using fast cooling processes or by evaporation in a moist atmosphere, micrometer size phase-separated domains have been clearly identified by Raman Confocal. This allowed us to analyze cell adhesion as well as proliferation on both planar (those obtained from melt quenching) and microporous surfaces (those obtained by the breath figures approach) formed from different blend compositions. Using C166-GFP and RAW264.7 cell types as a model we could observe an improved adhesion of the C166-GFP on top of the microporous surfaces evidencing the role of the surface topography on the cell adhesion process. In addition, preliminary results on the RAW264.7 cell adhesion indicated the polarization to M2 phenotypes instead of M1 which is a pre-requisite for the potential use of this material for implantology purposes.

Protein Expression Analysis of an In Vitro Murine Model of Prostate Cancer Progression: Towards Identification of High-Potential Therapeutic Targets.

Background: Prostate cancer (PC) is the most frequently diagnosed cancer among men worldwide. The poor prognosis of PC is largely due to late diagnosis of the disease when it has progressed to advanced stages marked by androgen-independence. We interrogated proteomic signatures that embody the transition of PC from an androgen-dependent (AD) to an androgen-independent (AI) state. Methods: We have previously established AD and AI murine PC cell lines, PLum-AD and PLum-AI, respectively, which recapitulate primary and progressive PC at phenotypic and subcellular levels. We statistically surveyed global protein expression profiles in these cell lines. Differential profiles were functionally interrogated by pathways and protein–protein interaction network analyses. Results: Protein expression pattern analysis revealed a total of 683 proteins, among which 99 were significantly differentially altered in PLum-AI cells as compared to PLum-AD cells (45 increased and 54 decreased). Principal component analysis (PCA) revealed that the two different cell lines clearly separated apart, indicating a significant proteome expression difference between them. Four of the proteins (vimentin, catalase, EpCAM, and caspase 3) that were differentially expressed in PLum-AI cells compared to PLum-AD cells were subjected to biochemical validation by Western blotting. Biological process gene ontology (GO) analysis of the differentially expressed proteins demonstrated enrichment of biological functions and pathways in PLum-AI cells that are central to PI3 kinase and androgen receptor pathways. Besides, other relevant biological processes that are enriched in PLum-AI cells included cell adhesion and cell migration processes, cell and DNA damage, apoptosis, and cell cycle regulation. Conclusions: Our protein expression analysis of a murine in vitro model of PC progression identified differential protein spots that denote this progression and that comprise high-potential targets for early treatment of PC with a personalized patient-specific approach. Efforts are underway to functionally assess the potential roles of these proteins as therapeutic targets for PC progression.

Amygdalin Decreases Adhesion and Migration of MDA-MB-231 and MCF-7 Breast Cancer Cell Lines.

Cell adhesion, as dynamic interactions between cell-cell and cell-matrix, has an essential role in cancer cell migration. Integrins as cell membrane receptors are involved in cell adhesion and signal transduction. Aberrant expression of integrins is associated with the cancer cell adhesion. Targeting the process of cell adhesion and migration could be helpful to prevent cancer cell metastasis. Amygdalin is a cyanoglycoside compound with anti-cancer properties, while its effect on cancer cell adhesion is not completely clear. The cytotoxic effect of amygdalin on breast cancer cell lines (MCF-7 and MDA-MB- 231) and human skin fibroblast cell line as a normal cell, was evaluated through MTT assay. The cell adhesion assay and wound healing assay were performed to determine amygdalin effects on adhesion and migration of cancer cells. Further analysis was carried out to evaluate integrin α and β levels through real-time PCR. We demonstrated that amygdalin diminished the cell viability of both cell lines in a time and dose-dependent manner, while amygdalin did not have any toxicity on the human skin fibroblast cell line in the same dosages. Following amygdalin treatment, the adhesion of both studied cell lines to fibronectin and collagen I decrease, and this reduction is significantly greater in the case of binding to fibronectin compared to binding to collagen. The MDA-MB-231 cell migration was decreased greater than MCF-7 cells. The levels of α and β integrin were differentially regulated by amygdalin in both cancer cell lines. These results suggest that depending on cancer cell lines, amygdalin affects cancer cell adhesion and migration.

Dietary Oligofructose Alone or in Combination with 2'-Fucosyllactose Differentially Improves Recognition Memory and Hippocampal mRNA Expression.

Mounting evidence suggests that dietary oligosaccharides promote brain development. This study assessed the capacity of oligofructose (OF) alone or in combination with 2′-fucosyllactose (2′-FL) to alter recognition memory, structural brain development, and hippocampal gene expression. Beginning on postnatal day (PND) 2, male pigs received one of three milk replacers formulated to contain OF, OF + 2′-FL, or no oligosaccharides (CON). Pigs were tested on the novel object recognition task using delays of 1 or 48 h at PND 22. At PND 32–33, magnetic resonance imaging (MRI) procedures were used to assess structural brain development and hippocampal tissue was collected for analysis of mRNA expression. Pigs that consumed the OF diet demonstrated increased recognition memory after a 1 h delay, whereas those consuming diets containing OF + 2′-FL displayed increased recognition memory after a 48 h delay. Pigs fed OF or OF + 2′-FL exhibited a larger relative volume of the olfactory bulbs compared with CON pigs. Provision of OF or OF + 2′-FL altered gene expression related to dopaminergic, GABAergic, cholinergic, cell adhesion, and chromatin remodeling processes. Collectively, these data indicate that dietary OF and OF + 2′-FL differentially improve cognitive performance and affect olfactory bulb structural development and hippocampal gene expression.

FKBP10 Acts as a New Biomarker for Prognosis and Lymph Node Metastasis of Gastric Cancer by Bioinformatics Analysis and in Vitro Experiments.

PurposeTo explore the role of FKBP prolyl isomerase 10 (FKBP10) protein in the progression of gastric cancer.MethodsFour independent gastric cancer databases (GSE27342, GSE29272, GSE54129 and TCGA-STAD) were used to identify differentially expressed genes (DEGs). Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was used to identify the abnormally active pathways in patients with gastric cancer. Univariate Cox regression analysis was used to identify genes with stable prognostic value in gastric cancer patients based on three independent gastric cancer databases (GSE15459, GSE62254, TCGA-STAD). Gene set enrichment analysis (GSEA) was used to explore the possible pathways related to FKBP10. The reverse transcription-polymerase chain reaction (RT-PCR) was employed to determine the expression of FKBP10 mRNA in the HGC-27 and MKN-7 cell lines. Adhesion assay was used to detect changes in cell adhesion ability. FKBP10, ITGA1, ITGA2, ITGA5, ITGAV, ITGA6, P-AKT473, P-AKT308, AKT, and β-actin were evaluated by Western blot (WB).ResultsWe first performed differential expression genes (DEGs) screening of four independent GC databases (GSE27342, GSE29272, GSE54129 and TCGA-STAD). Eighty-nine genes showed consistent up-regulation in GC, the results of pathway analysis showed that they were related to “Focal adhesion”. The prognostic value of these 89 genes was tested in three independent GC databases GSE15459, GSE62254 and TCGA-STAD cohort. Finally, 12 genes, in which the expression of FKBP10 was prominently increased in patients with lymph node metastasis (LNM), showed stable prognostic value. The following gene set enrichment analysis (GSEA) also showed that FKBP10 is mainly involved in cell adhesion process, while adhesion experiments confirmed that cell adhesion was down-regulated after silencing FKBP10 in GC cells, and adhesion-related molecules integrin αV and α6 were down-regulated.ConclusionFKBP10 may be used as a marker for lymph node metastasis of GC and could be used as a potential target for future treatment of GC.

LPS-treatment of bovine endometrial epithelial cells causes differential DNA methylation of genes associated with inflammation and endometrial function

BackgroundLipopolysaccharide (LPS) endotoxin stimulates pro-inflammatory pathways and is a key player in the pathological mechanisms involved in the development of endometritis. This study aimed to investigate LPS-induced DNA methylation changes in bovine endometrial epithelial cells (bEECs), which may affect endometrial function. Following in vitro culture, bEECs from three cows were either untreated (0) or exposed to 2 and 8 μg/mL LPS for 24 h.ResultsDNA samples extracted at 0 h and 24 h were sequenced using reduced representation bisulfite sequencing (RRBS). When comparing DNA methylation results at 24 h to time 0 h, a larger proportion of hypomethylated regions were identified in the LPS-treated groups, whereas the trend was opposite in controls. When comparing LPS groups to controls at 24 h, a total of 1291 differentially methylated regions (DMRs) were identified (55% hypomethylated and 45% hypermethylated). Integration of DNA methylation data obtained here with our previously published gene expression data obtained from the same samples showed a negative correlation (r = − 0.41 for gene promoter, r = − 0.22 for gene body regions, p < 0.05). Differential methylation analysis revealed that effects of LPS treatment were associated with methylation changes for genes involved in regulation of immune and inflammatory responses, cell adhesion, and external stimuli. Gene ontology and pathway analyses showed that most of the differentially methylated genes (DMGs) were associated with cell proliferation and apoptotic processes; and pathways such as calcium-, oxytocin- and MAPK-signaling pathways with recognized roles in innate immunity. Several DMGs were related to systemic inflammation and tissue re-modelling including HDAC4, IRAK1, AKT1, MAP3K6, Wnt7A and ADAMTS17.ConclusionsThe present results show that LPS altered the DNA methylation patterns of bovine endometrial epithelial cells. This information, combined with our previously reported changes in gene expression related to endometrial function, confirm that LPS activates pro-inflammatory mechanisms leading to perturbed immune balance and cell adhesion processes in the endometrium.

STAT3 Inhibition by Centipede Scolopendra Extract in Liver Cancer HepG2 Cells and Orthotopic Mouse Models of Hepatocellular Carcinoma

ObjectiveTo observe the effects of Centipede Scolopendra extraction (CSE) on human liver cancer HepG2 cells and the nude mouse tumor model of liver orthotopic transplantation, and to explore the anti-liver cancer mechanism of the extract. MethodsHepG2 cells were respectively treated with CSE250 (250 μg/mL), CSE500 (500 μg/mL) and 5-FU, and control group was established. An enzymatic hydrolysis and acetone precipitation method was used to separate and purify CSE, which was then used to treat HepG2 cells. The CCK8 assay was used to detect the inhibition of cell proliferation and the half maximal inhibitory concentration (IC50) was calculated. Flow cytometry was used to analyze the cell cycle, and western blot was used to detect the expression of signal transduction and activator of transcription 3 (STAT3) pathway-related proteins in HepG2 cells treated with CSE. A nude mouse model with an orthotopic liver tumor was prepared. The mice were randomly divided into four groups, each containing 12 animals: the model group, the 5-FU group, the CSE10 group [10 mg/(kg·d)] and the CSE50 group [50 mg/(kg·d)]. The volume and mass changes in the nude mice with orthotopic transplanted tumors were observed. Western blot method was used to test the protein expression levels of p-STAT3 and p38 mitogen-activated protein kinase (p38MAPK). Tissues from the liver of mice in the model group and the CSE50 group were analyzed by using a protein tyrosine kinase (PTK) chip, and the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) function enrichment analysis of the differentially expressed proteins was performed. ResultsThis study showed that CSE significantly inhibited the proliferation of HepG2 cells (P < 0.05). After 48 h of CSE treatment, the cell cycle of HepG2 cells manifested as S phase and G2/M phase; p-STAT3 protein levels in the CSE groups were significantly lower than that in the control group (P < 0.05). Analysis of the tumor inhibition in the mice showed that the tumor masses and volume in CSE groups were lower (P < 0.05). The protein levels of p-STAT3 and p38MAPK in CSE50 group and 5-FU group decreased significantly (P < 0.05). PTK antibody chip screening results showed that CSE groups had a bidirectional regulation trend, and there were 23 up-regulated PTKs and six down-regulated PTKs. The GO and KEGG analyses showed that CSE exerted its anticancer effects through regulation of biological processes, including mitogen-activated protein kinase (MAPK) cascade, chemotaxis, cell invasion, cell adhesion, angiogenesis and other biological processes, and through signaling pathways, including the MAPK, phosphatidylinositol-3-kinase/serine threonine protein kinase (PI3K/AKT), and RAS signaling pathways. ConclusionsCSE can effectively inhibite the proliferation of HepG2 cells and effectively inhibite the growth of liver cancer orthotopic transplantation tumor. Its mechanism may be closely related to the regulation of STAT3, MAPK and PI3K/AKT signaling pathways.

A gene co-expression network analysis of the candidate genes and molecular pathways associated with feather follicle traits of chicken skin.

Back and thigh skin of chickens showed significant differences in the thickness and the feather follicle density and size, which are important traits for slaughtered chickens' appearance. In the present study, global gene expression profiling was conducted in the back and thigh skin of chickens using Microarray technology. The results showed that 676 genes were differentially expressed between back and thigh skin. The expression of the differentially expressed genes (DEGs), including PPP1R3C, IGF1, PTCHD1, HOXB6, FGF9, CAMK4, SHH, BMP8B, FOXN1 and PTGER2, was validated by real-time quantitative polymerase chain reaction (RT-qPCR), and the results were consistent with microarray results. Functional analysis revealed that the DEGs were significantly involved in cell proliferation, differentiation, apoptosis, adhesion and transport process, and the pathways were significantly mapped into the ECM-receptor interaction, peroxisome, focal adhesion, Hedgehog and PPAR signalling pathways. Protein-protein interaction network analysis suggested that signalling pathways related to feathers morphogenesis and development, such as Wnt, FGF, MAPK, SHH and BMP signalling pathways, occupied important positions in the network. Genes involved in these signalling pathways and adhesion molecules might play a vital role in skin and feather follicle development. Further single nucleotide polymorphism (SNP) association analysis of Wnt3A showed that the AC genotype of SNP g.255361 C>A significantly increased the feather follicle density of thigh skin. Our findings may provide new insights on candidate genes and pathways related to skin and feather follicle formation of chickens.

Correction

Correction

Microfluidic adhesion analysis of single glioma cells for evaluating the effect of drugs

Cancer metastasis is one of the most serious problems for tumor therapy, which is closely related to cell adhesion and deadhesion process. Better comprehension of cell adhesion ability will benefit drug research. Here, a biomimetic microfluidic enzyme digestion method was proposed to gently measure the influence of drugs on cell-matrix adhesion ability at the single cell level. The method can selectively digest the extracellular matrix (ECM) that linked to a single cell, and the trypsin concentration around the cell is relatively uniform and constant, thus the measured cell adhesion strength should be precise. Commercially available anti-cancer agents including 5-fluorouracil (5-FU), actinomycin D (Act D), temozolomide (TMZ) and allicin were evaluated, and the data showed only TMZ and allicin can inhibit cell adhesion significantly under our experiment conditions. The influence of TMZ became more and more obvious as the increase of duration and the effect became prominent only after 6 h adhesion process, which could provide a quick evaluation of whether the drugs are effective to cancer cell (compared with Calcein-AM/PI cell viability test). The adhesion strength of U87 cells decreased when the concentration of TMZ increased, and the effect of TMZ can be effectively inhibited by adding lactic acid to culture medium, which indicated acidic tumor microenvironment could promote drug resistance of tumor cells. Different from conventional evaluation methods which focus on the drugs’ influence on cellular viability or metabolism, this work provides a new perspective to study the effect of drugs, which is helpful to enrich the drug evaluation system.

Dendritic Scaffold onto Titanium Implants. A Versatile Strategy Increasing Biocompatibility.

Osseointegration of metal prosthetic implants is a yet unresolved clinical need that depends on the interplay between the implant surface and bone cells. The lack of a relationship between bone cells and metal has traditionally been solved by coating the former with “organic” ceramics, such as hydroxyapatite. A novel approach is hereby presented, immobilizing covalently dendrimeric structures onto titanium implants. Amide-based amino terminal dendrons were synthetized and coupled to titanium surfaces in a versatile and controlled way. The dendritic moieties provide an excellent scaffold for the covalent immobilization of bioactive molecules, such as extracellular matrix (ECM) protein components or antibiotics. Herein, tripeptide arginine-glycine-aspartic acid (RGD) motifs were used to decorate the dendritic scaffolds and their influence on cell adhesion and proliferation processes was evaluated.

Identification of Key Factors in Cardiomyocyte Development by Single‐Cell Transcriptome Analysis

BackgroundA promising intervention for heart diseases is the application of cardiomyocytes differentiated from pluripotent stem cells. However, the driving factors of the differentiation process still remain unclear. This study aims to map the transcriptional landscapes of directional differentiation of pluripotent stem cells at multiple stages, using single‐cell sequencing data, in order to identify the key drivers of the differentiation process.MethodSingle‐cell sequencing data from pluripotent stem cell‐derived cardiomyocytes at age day 0, day 2, day 5, day 15 and day 30 were included and normalized. UMAP algorithm was then used to reduce the dimensionality of the transcriptome profiles, followed by community detection to group the cells and cell type identification using marker genes. Graph‐autocorrelation analysis was implemented to identify differentially expressed genes among cell groups with Gene Ontology term enrichment. Next, we calculated the pseudotimes of each cardiomyocyte to construct the pseudotime trajectories. Finally, knowledge based dynamic changes in gene expression were analyzed to identify the key factors driving the cardiomyocyte development.ResultWe identified 9 different cell types in the process of cardiomyocyte development, including cardiomyocytes, induced pluripotent stem cells, cardiogenic mesoderm cells, cardiovascular progenitor cells, embryonic stem cells, endoderm cells, epithelial progenitor cells, cardiomyocyte progenitor cells and multipotent progenitor cells. Identification of cardiomyocyte was confirmed with specific gene expression profiles such as significant enrichment in the biological processes of cell adhesion and supramolecular fiber organization. The expression of NKX2‐5, which encodes a homeobox‐containing transcription factor, was found to be at a lower level in the early stages and continually increased as cardiomyocyte develop, suggesting that NKX2‐5 was one of the driving factors of cardiac development, acting through promoting myocardial maturation and development.ConclusionSingle cell sequencing data revealed the dynamic changes of gene expression during cardiomyocyte development differentiation. NKX2‐5 was identified as a key factor in cardiac development. Our finding contributes to the understanding of the mechanism behind the cardiomyocyte development, and may serve as the basis for stem cell based therapies.Support or Funding InformationThis work was supported by National Natural Science Foundation of China 81774152 (to RZ) and 81770571 (to LZ).

Transcriptome analysis of tongue cancer based on high‑throughput sequencing.

Tongue cancer is one of the most common types of cancer, but its molecular etiology and pathogenesis remain unclear. The aim of the present study was to elucidate the pathogenesis of tongue cancer and investigate novel potential diagnostic and therapeutic targets. Four matched pairs of tongue cancer and paracancerous tissues were collected for RNA sequencing (RNA-Seq), and the differentially expressed genes were analyzed. The RNA-Seq data of tongue cancer tissues were further analyzed using bioinformatics and reverse transcription-quantitative PCR analysis. The sequenced reads were quantified and qualified in accordance with the analysis demands. The transcriptomes of the tongue cancer tissues and paired paracancerous tissues were analyzed, and 1,700 upregulated and 2,249 downregulated genes were identified. Gene Ontology analysis uncovered a significant enrichment in the terms associated with extracellular matrix (ECM) organization, cell adhesion and collagen catabolic processes. Kyoto Encyclopedia of Genes and Genomes analysis demonstrated that these differentially expressed genes were mainly enriched in the focal adhesion pathway, ECM-receptor interaction pathway, phosphoinositide 3-kinase (PI3K)-Akt pathway, and cell adhesion molecules. Comprehensive analyses of the gene tree and pathway network revealed that the majority of cell cycle genes were upregulated, while the majority of the genes associated with intracellular response, cell adhesion and cell differentiation were downregulated. The ECM-receptor interaction, focal adhesion kinase (FAK) and PI3K-Akt pathways were closely associated with one another and held key positions in differential signaling pathways. The ECM-receptor, FAK and PI3K-Akt signaling pathways were found to synergistically promote tongue cancer occurrence and progression, and may serve as potential diagnostic and therapeutic targets for this type of cancer.

Physical understanding of the bending of nanostructures caused by cellular force.

The bending of nanostructures (NSs), such as nanopillars and nanowires, caused by cell adhesion is an interesting phenomenon and is important for the measurements of cellular forces, understanding the biological behavior of cells, and disease diagnosis. However, which factors are related to the bending of NSs and how the factors affect bending displacement are still not well understood. Here, we establish an analytic thermodynamic theory to study the bending mechanism of NSs caused by cellular force during the cell adhesion process, and analyze the factors affecting bending displacement. It is found that the bending of NSs is determined by the competition between the stretching energy of the membrane and the strain energy of the NSs. The bending displacement can be evaluated based on our model.

Abstract P1-10-19: Tyrosine aminoacyl-tRNA synthetase sensitizes breast cancer to chemotherapy througha necroptosis-mediated mechanism: High-throughput proteomics and machine learningalgorithm based feature selection analyses

Abstract Although more than 70% of entire patients are currently receiving the chemotherapy regimen, pathologic complete response (pCR) rate is still low. Therefore, the need for a marker predictive of response to a particular cytotoxic regimen is becoming all the more necessary to optimize therapeutic efficacy and to avoid unnecessary complications. We performed quantitative proteomics in FFPE biopsy breast cancer samples consist of non-responsive and responsive groups to chemotherapy. To define the best classifier to evaluate the predictive power of signatures, we employed four different machine learning algorithms and performed repeated cross-validation on the training set to classify samples between pCR and non-pCR groups. The candidate proteins selected from the machine-learning algorithms were subsequently validated by immunohistochemistry of 123 cases of independent needle biopsy FFPE samples. The further experimental model of breast cancer was performed to identify the molecular mechanism of how the biomarker potentiates sensitivity of multiple breast cancer cells to chemotherapy response and synergistic effect with a combination of necroptotic mimetics. The filtered dataset was subjected to statistical analysis using Student’s t-test (p-value &amp;lt; 0.05), which resulted in 539 proteins with differential abundances. To identify the most meaningful changes in two conditions, the volcano plot was used and 13 proteins were prioritized. We searched for biological process in the Gene Ontology (GO) enrichment analysis in each proteomic cluster. Several immune responses process, apoptotic process, DNA replication process, and aminoacylation for protein translation process primarily were represented in the group with complete remission. On the other hand, cell adhesion process, cytoskeleton organization process, vesicle organization process and Golgi organization process overrepresented in breast cancer which showed poor responses to the therapy. The machine learning approaches demonstrated the highest AUC value, 0.978 (sensitivity 1.0 and specificity 0.714) with a combination of 11 proteins. For the accuracy prediction, four different algorithms demonstrated evenly high accuracy rates from 0.85 to 0.95 with a combination of the selected seven candidates. They were evaluated in the subsequent steps of verification using immunohistochemistry (IHC) in 123 patient cohorts. The predictive relevance of individual proteins, YARS to distinguish CR from nCR was AUC of 0.749 for all cases. The overexpression of YARS induced chemotherapeutic sensitivity in hormone receptor-positive breast cancer cell lines such as T47D, which was confirmed with multiple molecular biology-driven assays. The further experimental model of breast cancer demonstrated that YARS induced tumor necroptosis which enhanced chemotherapy response and was synergized with a combination of SMAC mimetics that is a potent necroptosis inducer. In summary, our discovery data provide a global molecular landscape for determining chemotherapy response in breast cancer at the proteome level. Furthermore, we provided a novel protein candidate to predict chemotherapy response and identify a novel protein YARS in combination with Smac mimetics synergistically induced necroptosis which produces more cell death in response to combined chemotherapy in breast cancer. Citation Format: Han Suk Ryu. Tyrosine aminoacyl-tRNA synthetase sensitizes breast cancer to chemotherapy througha necroptosis-mediated mechanism: High-throughput proteomics and machine learningalgorithm based feature selection analyses [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-10-19.

Surface Modification of PTLG Terpolymer Using PNIPAAm and Its Cell Adhesion/Detachment Behavior

AbstractNovel biodegradable terpolymer poly (1,3‐trimethylene carbonate‐b‐(l‐lactide‐r‐glycolide)) grafted with poly(N‐isopropylacrylamide) (PTLG‐PNIPAAm) is prepared by plasma‐induced polymerization. The experimental results show that PNIPAAm segments of samples have a dramatic effect on surface layer structure and cell behavior of PTLG‐PNIPAAm. The thickness of PNIPAAm layer on PTLG surface increases rapidly from 50 nm to 1 µm with the molecular weight of samples increasing. Cell toxicity analysis indicates that PTLG‐PNIPAAm possesses good cytocompatibility to human adipose‐derived stem cells (hADSCs). For cell adhesion and detachment process on modified surface, the “hook and loop” process is proposed to understand the cell adhesion on modified surface with coiled conformation PNIPAAm segments at 37 °C, and then the cell sheet detached from surface spontaneously due to the conformation of PNIPAAm segments extends below its lower critical solution temperature. The research demonstrates that with increasing thickness of the PNIPAAm layer on PTLG surface, the hADSCs with well cell viability presents rapider thermal‐responsive detachment behavior. Therefore, the surface modification of biodegradable PTLG with stimuli‐sensitive functional PNIPAAm is an efficacious route for further application in stem cell culture and tissue engineering stent.

Novel and Known Gene-Smoking Interactions With cIMT Identified as Potential Drivers for Atherosclerosis Risk in West-African Populations of the AWI-Gen Study

IntroductionAtherosclerosis is a key contributor to the burden of cardiovascular diseases (CVDs) and many epidemiological studies have reported on the effect of smoking on carotid intima-media thickness (cIMT) and its subsequent effect on CVD risk. Gene-environment interaction studies have contributed towards understanding some of the missing heritability of genome-wide association studies. Gene-smoking interactions on cIMT have been studied in non-African populations (European, Latino-American, and African American) but no comparable African research has been reported. Our aim was to investigate smoking-SNP interactions on cIMT in two West African populations by genome-wide analysis.Materials and methodsOnly male participants from Burkina Faso (Nanoro = 993) and Ghana (Navrongo = 783) were included, as smoking was extremely rare among women. Phenotype and genotype data underwent stringent QC and genotype imputation was performed using the Sanger African Imputation Panel. Smoking prevalence among men was 13.3% in Nanoro and 42.5% in Navrongo. We analyzed gene-smoking interactions with PLINK after adjusting for covariates: age and 6 PCs (Model 1); age, BMI, blood pressure, fasting glucose, cholesterol levels, MVPA, and 6 PCs (Model 2). All analyses were performed at site level and for the combined data set.ResultsIn Nanoro, we identified new gene-smoking interaction variants for cIMT within the previously described RCBTB1 region (rs112017404, rs144170770, and rs4941649) (Model 1: p = 1.35E-07; Model 2: p = 3.08E-08). In the combined sample, two novel intergenic interacting variants were identified, rs1192824 in the regulatory region of TBC1D8 (p = 5.90E-09) and rs77461169 (p = 4.48E-06) located in an upstream region of open chromatin. In silico functional analysis suggests the involvement of genes implicated in biological processes related to cell or biological adhesion and regulatory processes in gene-smoking interactions with cIMT (as evidenced by chromatin interactions and eQTLs).DiscussionThis is the first gene-smoking interaction study for cIMT, as a risk factor for atherosclerosis, in sub-Saharan African populations. In addition to replicating previously known signals for RCBTB1, we identified two novel genomic regions (TBC1D8, near BCHE) involved in this gene-environment interaction.