Identification of Key Pathways and Genes in Advanced...

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Research Article Identification of Key Pathways and Genes in Advanced Coronary Atherosclerosis Using Bioinformatics Analysis Xiaowen Tan, 1 Xiting Zhang, 1 Lanlan Pan, 1,2 Xiaoxuan Tian, 1,2 and Pengzhi Dong 1,2 1 Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, China 2 Research and Development Center of TCM, Tianjin International Joint Academy of Biotechnology & Medicine, Tianjin, China Correspondence should be addressed to Xiaoxuan Tian; tian [email protected] and Pengzhi Dong; [email protected] Received 14 June 2017; Accepted 17 September 2017; Published 31 October 2017 Academic Editor: Harry W. Schroeder Copyright © 2017 Xiaowen Tan et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background. Coronary artery atherosclerosis is a chronic inflammatory disease. is study aimed to identify the key changes of gene expression between early and advanced carotid atherosclerotic plaque in human. Methods. Gene expression dataset GSE28829 was downloaded from Gene Expression Omnibus (GEO), including 16 advanced and 13 early stage atherosclerotic plaque samples from human carotid. Differentially expressed genes (DEGs) were analyzed. Results. 42,450 genes were obtained from the dataset. Top 100 up- and downregulated DEGs were listed. Functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) identification were performed. e result of functional and pathway enrichment analysis indicted that the immune system process played a critical role in the progression of carotid atherosclerotic plaque. Protein-protein interaction (PPI) networks were performed either. Top 10 hub genes were identified from PPI network and top 6 modules were inferred. ese genes were mainly involved in chemokine signaling pathway, cell cycle, B cell receptor signaling pathway, focal adhesion, and regulation of actin cytoskeleton. Conclusion. e present study indicated that analysis of DEGs would make a deeper understanding of the molecular mechanisms of atherosclerosis development and they might be used as molecular targets and diagnostic biomarkers for the treatment of atherosclerosis. 1. Introduction Atherosclerosis associated cardiovascular diseases (CVD) are the leading cause of mortality worldwide. Immune system responses play a pivotal role in all phases of atheroscle- rosis [1] and inflammation responses contribute to focal plaque vulnerability [2]. High-level LDL in plasma and other atherosclerosis-prone conditions expedite immune cell recruitment into the lesion area in the early and advanced stages [3–5]. Variety of inflammatory process was identified during atherosclerosis progression, which might be amenable to interventions. High-throughput platforms for analysis of gene expres- sion, such as microarrays, are the promising tools for inferring biological relevancy, especially complex network during the process of atherosclerosis. Recently, atheroscle- rotic gene expression profiling studies have been performed by microarray technology and suggested that hundreds of differentially expressed genes (DEGs) are involved in vari- ety pathways, biological processes, or molecular functions. Microarray technology combined bioinformatics analysis made it possible to analyze the expression changes of mRNA from early to advanced stage of coronary atherosclerosis development, comprehensively. Samples from early ((patho- logical) intimal thickening and intimal xanthoma) and from advanced (thin or thick fibrous cap atheroma) lesions have been retrieved from the Maastricht Pathology Tissue Collec- tion (MPTC) [6]. However, the protein-protein interactions (PPI) network among DEGs remains to be elucidated. In this study, the original data was downloaded from Gene Expression Omnibus (GEO). DEGs from early and advanced lesions were screened. Subsequently, the gene ontology and biological function annotation were performed followed by PPI network analysis. By using the bioinformatic Hindawi BioMed Research International Volume 2017, Article ID 4323496, 12 pages https://doi.org/10.1155/2017/4323496

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Research ArticleIdentification of Key Pathways and Genes in Advanced CoronaryAtherosclerosis Using Bioinformatics Analysis

Xiaowen Tan,1 Xiting Zhang,1 Lanlan Pan,1,2 Xiaoxuan Tian,1,2 and Pengzhi Dong1,2

1Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, China2Research and Development Center of TCM, Tianjin International Joint Academy of Biotechnology & Medicine, Tianjin, China

Correspondence should be addressed to Xiaoxuan Tian; tian [email protected] Pengzhi Dong; [email protected]

Received 14 June 2017; Accepted 17 September 2017; Published 31 October 2017

Academic Editor: Harry W. Schroeder

Copyright © 2017 Xiaowen Tan et al. This is an open access article distributed under the Creative Commons Attribution License,which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Background. Coronary artery atherosclerosis is a chronic inflammatory disease. This study aimed to identify the key changes ofgene expression between early and advanced carotid atherosclerotic plaque in human.Methods. Gene expression dataset GSE28829was downloaded from Gene Expression Omnibus (GEO), including 16 advanced and 13 early stage atherosclerotic plaque samplesfrom human carotid. Differentially expressed genes (DEGs) were analyzed. Results. 42,450 genes were obtained from the dataset.Top 100 up- and downregulated DEGs were listed. Functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG) identification were performed.The result of functional and pathway enrichment analysis indicted that the immune systemprocess played a critical role in the progression of carotid atherosclerotic plaque. Protein-protein interaction (PPI) networkswere performed either. Top 10 hub genes were identified from PPI network and top 6 modules were inferred. These genes weremainly involved in chemokine signaling pathway, cell cycle, B cell receptor signaling pathway, focal adhesion, and regulation ofactin cytoskeleton. Conclusion. The present study indicated that analysis of DEGs would make a deeper understanding of themolecular mechanisms of atherosclerosis development and they might be used as molecular targets and diagnostic biomarkersfor the treatment of atherosclerosis.

1. Introduction

Atherosclerosis associated cardiovascular diseases (CVD) arethe leading cause of mortality worldwide. Immune systemresponses play a pivotal role in all phases of atheroscle-rosis [1] and inflammation responses contribute to focalplaque vulnerability [2]. High-level LDL in plasma andother atherosclerosis-prone conditions expedite immune cellrecruitment into the lesion area in the early and advancedstages [3–5]. Variety of inflammatory process was identifiedduring atherosclerosis progression, whichmight be amenableto interventions.

High-throughput platforms for analysis of gene expres-sion, such as microarrays, are the promising tools forinferring biological relevancy, especially complex networkduring the process of atherosclerosis. Recently, atheroscle-rotic gene expression profiling studies have been performed

by microarray technology and suggested that hundreds ofdifferentially expressed genes (DEGs) are involved in vari-ety pathways, biological processes, or molecular functions.Microarray technology combined bioinformatics analysismade it possible to analyze the expression changes of mRNAfrom early to advanced stage of coronary atherosclerosisdevelopment, comprehensively. Samples from early ((patho-logical) intimal thickening and intimal xanthoma) and fromadvanced (thin or thick fibrous cap atheroma) lesions havebeen retrieved from the Maastricht Pathology Tissue Collec-tion (MPTC) [6]. However, the protein-protein interactions(PPI) network among DEGs remains to be elucidated.

In this study, the original data was downloaded fromGene Expression Omnibus (GEO). DEGs from early andadvanced lesions were screened. Subsequently, the geneontology and biological function annotation were performedfollowed by PPI network analysis. By using the bioinformatic

HindawiBioMed Research InternationalVolume 2017, Article ID 4323496, 12 pageshttps://doi.org/10.1155/2017/4323496

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method, further investigation on mechanism of atheroscle-rosis was lighted and it might provide potential biomarkercandidates for clinical use and drug targets discovery.

2. Materials and Methods

2.1. Microarray Data. The gene expression profiles ofGSE28829 were downloaded from Gene ExpressionOmnibus (GEO). GSE28829 was performed on GPL570,[HG-U133 Plus 2] Affymetrix Human Genome U133 Plus2.0 Array. The GSE28829 data set contained 29 samples,including 16 advanced atherosclerotic plaque samples and 13early atherosclerotic plaque samples.

2.2. Identification of Differentially Expression Genes (DEGs).The analysis was carried out by Morpheus (https://software.broadinstitute.org/morpheus/). The expression files wereuploaded. Advanced and early stages of atheroscleroticplaque were assigned according to the annotation ofthe GSE28829 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE28829). DEGs were identified using signal tonoise method where a total of 42,450 genes were analyzedand top 100 (top 100 upregulated and top 100 downregulatedgenes) genes were listed.

2.3. Gene Ontology and Pathway Enrichment Analysis ofDEGs. Cellular component, molecular function, biologicalprocess, and Kyoto Encyclopedia of Genes and Genomes(KEGG)were analyzed using aweb-based tool, search tool forthe retrieval of interacting genes (STRING) (https://string-db.org/). Due to limitation of the settings of the tool, top 2000upregulated genes and top 2000 downregulated genes wereanalyzed.

2.4. Integration of Protein-Protein Interaction (PPI) Networkand Module Analysis. STRING (version 10.0) was used toevaluate the interactive (PPI) relationships between DEGs.Only experimentally validated interactions with a combinedscore >0.4 were selected as significant. PPI networks wereconstructed using the Cytoscape software. A plug-in molec-ular complex detection (MCODE) was used to screen themodules of PPI network identified in Cytoscape. Modulesinferred using the default settings that the degree cutoff wasset at 2, node score cutoff was set at 0.2, 𝐾-core was set at 2,and max. depth was 100.

2.5. Pathways Interrelation Analysis. Pathways interrelationanalysis was carried out using plug-in ClueGO v2.3.3. Genescomposed ofmodules A andD (inferred fromMCODE)wereanalyzed. KEGG was conducted and pathways with 𝑃 < 0.05were showed in Figure 3.

3. Results

3.1. Identification of Differentially Expressed Genes (DEGs).29 samples from atherosclerotic carotid artery segments, 16advanced and 13 early lesions included, have been retrieved

from the Maastricht Pathology Tissue Collection (MPTC).The series from each chip was analyzed by Morpheus usingsignal to noise method to find out as much as possible genesup- or downregulated. Among the total 42,450 genes, themost significant signal of upregulated gene is C2, and thesignal to noise score is 1.792. The most significant signal ofdownregulated gene isH2AFVwhere the signal to noise scoreis −2.249. All the DEGs were listed (data not shown). Top 100upregulated and downregulated genes were listed, as shownin Figure 1.

3.2. Gene Ontology and Pathway Enrichment Analysis. Dueto the limited number of nods of the tool, we selected the top2,000DEGs, 2000 up- and downregulated genes, respectively.Top 5 enrichment analyses were showed for each part ofgene ontology (GO) analysis. The results showed that theupregulated genes significantly took part in the formation ofcellular components (GO) that were lysosome (GO.0005764),vacuole (GO.0005773), plasma membrane (GO.0005886),cell periphery (GO.0071944), and plasma membrane part(GO.0044459). Downregulated genes were mainly involvedin construction of cytoplasm (GO.0005737), intracellularorganelle (GO.0043229), organelle part (GO.0044422),cytoplasmic part (GO.0044444), and intracellular organellepart (GO.0044446), as shown in Table 1. The molecularfunction (GO) enrichment analysis showed that theupregulated genes were mainly involved in proteinbinding (GO.0005515), receptor binding (GO.0005102),molecular transducer activity (GO.0060089), molecularfunction (GO.0003674), and binding (GO.0005488).Downregulated genes mainly revolved in protein binding(GO.0005515), binding (GO.0005488), cytoskeletal proteinbinding (GO.0008092), enzyme binding (GO.0019899),and nucleotide binding (GO.0000166) as shown inTable 2. Biological process enrichment analysis showedthat upregulated genes take part in the immune systemprocess (GO.0002376), defense response (GO.0006952),regulation of immune system process (GO.0002682),immune response (GO.0006955), and regulation ofimmune response (GO.0050776). Downregulated genestake part in cytoskeleton organization (GO.0007010),cellular component organization (GO.0016043), positiveregulation of cellular process (GO.0048522), regulationof cellular component organization (GO.0051128), andcellular component organization or biogenesis (GO.0071840)as shown in Table 3. Kyoto Encyclopedia of Genes andGenomes (KEGG) pathways enrichment analysis wasconducted where the upregulated genes are enriched inosteoclast differentiation (4380), cytokine-cytokine receptorinteraction (4060), chemokine signaling pathway (4062),lysosome (4142), and Staphylococcus aureus infection (5150).Downregulated genes are enriched in focal adhesion (4510),regulation of actin cytoskeleton (4810), arrhythmogenicright ventricular cardiomyopathy (ARVC) (5412), oxytocinsignaling pathway (4921), and cGMP-PKG signaling pathway(4022).

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Table 1: Cellular component (GO) enrichment analysis in networks.

Expression #Pathway ID Pathway description Observed gene count False discovery rate

Upregulated

GO.0005764 Lysosome 103 1.02𝐸 − 25

GO.0005773 Vacuole 112 1.32𝐸 − 25

GO.0005886 Plasma membrane 441 1.46𝐸 − 25

GO.0071944 Cell periphery 446 1.46𝐸 − 25

GO.0044459 Plasma membrane part 268 1.30𝐸 − 24

Downregulated

GO.0005737 Cytoplasm 807 9.90𝐸 − 37

GO.0043229 Intracellular organelle 838 1.42𝐸 − 26

GO.0044422 Organelle part 639 3.03𝐸 − 26

GO.0044444 Cytoplasmic part 611 3.03𝐸 − 26

GO.0044446 Intracellular organelle part 628 3.03𝐸 − 26

Table 2: Molecular function (GO) enrichment analysis in networks.

Expression #Pathway ID Pathway description Observed gene count False discovery rate

Upregulated

GO.0005515 Protein binding 445 7.57𝐸 − 24

GO.0005102 Receptor binding 148 1.76𝐸 − 16

GO.0060089 Molecular transducer activity 194 1.39𝐸 − 14

GO.0003674 Molecular function 889 4.21𝐸 − 12

GO.0005488 Binding 761 4.21𝐸 − 12

Downregulated

GO.0005515 Protein binding 426 8.46𝐸 − 22

GO.0005488 Binding 740 3.00𝐸 − 12

GO.0008092 Cytoskeletal protein binding 79 7.43𝐸 − 12

GO.0019899 Enzyme binding 151 7.43𝐸 − 12

GO.0000166 Nucleotide binding 218 1.07𝐸 − 08

Table 3: Biological process (GO) enrichment analysis in networks.

Expression #Pathway ID Pathway description Observed gene count False discovery rate

Upregulated

GO.0002376 Immune system process 321 7.44𝐸 − 63

GO.0006952 Defense response 252 5.46𝐸 − 56

GO.0002682 Regulation of immune system process 246 8.58𝐸 − 56

GO.0006955 Immune response 241 2.11𝐸 − 55

GO.0050776 Regulation of immune response 175 4.95𝐸 − 49

Downregulated

GO.0007010 Cytoskeleton organization 109 2.81𝐸 − 12

GO.0016043 Cellular component organization 386 2.81𝐸 − 12

GO.0048522 Positive regulation of cellular process 362 2.81𝐸 − 12

GO.0051128 Regulation of cellular component organization 211 6.71𝐸 − 12

GO.0071840 Cellular component organization or biogenesis 390 1.02𝐸 − 11

3.3. Module Screening from the Protein-Protein Interaction(PPI) Network. Based on the information in the STRINGdatabase, top 10 hub genes were screened. These genes areubiquitin A-52 residue ribosomal protein fusion product 1(UBA52), ribosomal protein L38 (RPL38), integrin subunitalpha L (ITGAL), intercellular adhesionmolecule 1 (ICAM1),

interleukin 7 receptor (IL7R), interleukin 7 (IL7), REL pro-tooncogene, NF-KB subunit (REL), NF-KB inhibitor alpha(NFKBIA), Vav guanine nucleotide exchange factor 1 (VAV1),and lymphocyte cytosolic protein 2 (LCP2). 2693 nods and9212 edges were analyzed using the plug-in MCODE inCytoscape. The top 6 significant modules were selected;

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row min row max

ComparisonA

B

GSM

7140

84G

SM71

4070

GSM

7140

72G

SM71

4073

GSM

7140

74G

SM71

4075

GSM

7140

76G

SM71

4077

GSM

7140

78G

SM71

4079

GSM

7140

80G

SM71

4081

GSM

7140

82G

SM71

4083

GSM

7140

71G

SM71

4085

GSM

7140

92G

SM71

4086

GSM

7140

88G

SM71

4089

GSM

7140

90G

SM71

4091

GSM

7140

87G

SM71

4093

GSM

7140

94G

SM71

4095

GSM

7140

96G

SM71

4097

GSM

7140

98

ID_REF

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

adva

nced

early

early

early

early

early

early

early

early

early

early

early

early

early

TypeComparison

C2CD180DENND2DCYTH4GRB2SLAMF8WDFY4CD68 /// LOC101928634 /// SNORA67ADAP2JAK3TMC8LINC01094CD6P2RX7LGALS9PLXND1SERPINA1SLAMF8VAV1CTSBVAMP8KCNAB2AMPD3C3AR1BTKTMC6SERPINA1BATFSLC38A7LCP2LAIR1SASH3SGK223CD84CD52CD84CTSBPARVGMTMR14IFNAR2CD84IFI30 /// PIK3R2SIGLEC7CTSCPLCG2RBM471-MarITGB2FCGBPPLTPGRNCCR1PIK3AP1ADAP2PARVGPLCB2CTSBGRNARHGAP9PARP12ITGB2CTSBMYO1FCSKCCR5CD48LAPTM5FCGR1A /// FCGR1B /// FCGR1CARPC1BTPP1GALNT6CD14FCGR1BGRNC1QBSLC7A7TIMP1PTPN6CD52APOEDOK3CASP1FERMT3LILRB2IGSF61-MarMFNGKCNJ5LRRC25DUSP23KMOCTSLKYNURUNX1-IT1RBM47CTSBAIF1SELPLGARHGAP30TNFSF13CTSSDAB2 /// LOC101926921SLCO2B1TLR2TMEM176ACASP1DAB2 /// LOC101926921RUNX3LAIR1LAT2ARHGAP25CNPY3ADORA3ALOX5KCNJ5DISC1 /// TSNAX-DISC1HLA-DQB1 /// LOC101060835C1QAGNA15AIF1KIAA0226LNRROSMETTL7BIGH /// IGHA1 /// IGHA2CD28RAC2RPS6KA1AIF1HCKFCGR2CDAB2 /// LOC101926921MGAT4ASIRPACYBACD37CMTM7CYBBHAVCR2OSBPL3CD163L1TYROBPNAGK1-MarITGALAPOESNX20HLA-DMBCCL19KIAA0226LIL17RANPC2ACP5IGLC1PYCARDPOU2F2CTSCGPSM3VAV3MAPK13IGLC1LILRB1NLRC4GIMAP4CA12CA12P2RX7RNASE1MS4A4ACCL4ITGALTNFSF12-TNFSF13 /// TNFSF13DSC2PTGS1CYAT1 /// IGLC1 /// IGLV1-44CTSSCD53HLA-DQB1 /// LOC101060835ABCA1FYBGUSBP11ARHGAP25TNFSF13BNUDT14PLA2G7CORO1ALAPTM5LST1STK10FBP1HLA-DRB6AMICA1SLCO2B1LILRB1NPLLY86NCF4KLHL6ASPMGMFGCDK1HADHDNM1LFBLN5VCLFBXL2DNAJB5DSTNXKSGCBCOQ10BCCNB1IP1PRICKLE2RAB9BGAREMBMPR1APTPN21N4BP2L2NDRG3DNAJB6METAP1SSBP2IPW /// LOC101930404 /// PWARSN /// SNORD107 /// SNORD115-13 /// SNORD115-26 /// SNORD115-7 /// SNORD116-22 /// SNORD116-28 /// SNORD116-4KIAA0232PHF10PCID2ACADLYAP1DSTNTLE1CLIC4TP53BP2TAF9BABCD3MSRB3SSPNFEM1BACP6AIFM2VCLMSRB3USP16LOC100287497TMEM38BRBM27TLE1CKBCSDE1PNNZNRF3ETF1PPP1R12AKCTD7 /// RABGEF1DMDS1PR3KANK2IPO5SPOPCNIH4RBBP7SYT11MYO1BHLFPPP2CBACTN2MOB4ACADLMORC4PTPN21CPEPPP1CBFAM20BLPAR1SPOPLHADHSYT11SLC41A2ACSL3TIMM23BFAM131APJA2CAB39LIDSTMOD1KIF5BFERMT2RHBDF1CTNNA1MYLKIPO7GPD1LRNF115NUDT4 /// NUDT4P1SBSPONCFL2MAP2IPO5SLMAPMSI2ZFYVE21CFL2EPM2ACPED1PTPN11RRAS2TMEM246LOC100996668 /// ZEB1TMEM43SKP1CNTN4ATXN3TPM1CTNNA1ROCK1DMDACSS3PRKRAENSAOXCT1APBB2CFL2CRTAPNPNTPALLDC3orf70SGCBSLMAPSH3BGRTPM1CRTAPAPBB2C14orf132GPR125YWHAQARCN1CLDND1ANGPTL1USP16PIP5K1BBHMT2DYNLT3LARP1BFBXO30MSRB3SGCESAR1BTERF2IPLSM14ACDC73VKORC1L1BRMS1LLOC101928625 /// MED21MTURNPAFAH1B1PID1KCMF1MXRA7ODC1MBNL1-AS1PPM1APALLDATP1A2RAP1ARAB2BCTNNA1EIF1SYNJ2BP /// SYNJ2BP-COX16ZBTB10CALM1 /// CALM2 /// CALM3LSM14ADYNC1LI2YIPF6PREPLRNF115MAPK9RPRD1ALRRFIP2SBDS /// SBDSP1CRYABSLC16A1SLMAPNDFIP1MAP4BAG2BTCMRFAP1ANGPTL1TMEM35MBNL1-AS1FAM20BRAB21REEP5PREPLFERMT2ANGPTL1DCUN1D4SKP1BHMT2PALLDSBDS /// SBDSP1H2AFV

ID_REF1.791.691.621.601.591.561.561.551.491.481.461.461.441.431.431.431.431.431.421.401.401.401.391.391.391.381.381.381.381.371.371.371.361.361.361.351.331.331.321.321.321.311.311.311.311.301.301.301.291.291.291.291.281.281.281.281.281.271.271.261.261.261.261.261.261.261.251.251.251.251.251.241.241.241.241.241.231.231.231.231.231.221.221.221.221.221.211.211.211.211.211.211.211.201.201.201.201.191.191.191.181.181.181.181.171.171.171.171.171.161.161.161.161.161.161.161.161.161.161.161.161.161.161.151.151.151.151.151.151.151.151.141.141.141.141.131.131.131.131.131.121.121.121.121.121.121.121.121.111.111.111.111.111.111.101.101.101.101.101.101.101.101.101.101.091.091.091.091.091.091.091.091.091.091.091.081.081.081.081.081.081.081.081.081.081.081.081.081.081.081.081.081.081.081.071.071.071.071.071.07−0.96−0.96−0.96−0.96−0.96−0.96−0.96−0.97−0.97−0.97−0.97−0.97−0.97−0.97−0.97−0.97−0.97−0.98−0.98−0.98−0.98−0.98−0.98−0.98−0.98−0.98−0.98−0.98−0.98−0.98−0.98−0.98−0.99−0.99−0.99−0.99−0.99−0.99−0.99−0.99−0.99−1.00−1.00−1.00−1.00−1.00−1.00−1.00−1.00−1.01−1.01−1.01−1.01−1.01−1.01−1.01−1.01−1.01−1.01−1.01−1.01−1.01−1.02−1.02−1.02−1.02−1.02−1.03−1.03−1.03−1.03−1.03−1.03−1.03−1.04−1.04−1.04−1.04−1.05−1.05−1.05−1.05−1.05−1.05−1.05−1.05−1.06−1.06−1.06−1.06−1.06−1.06−1.06−1.07−1.07−1.07−1.07−1.07−1.07−1.07−1.07−1.07−1.07−1.08−1.08−1.08−1.08−1.08−1.08−1.08−1.08−1.08−1.08−1.08−1.08−1.08−1.08−1.09−1.09−1.09−1.09−1.10−1.10−1.10−1.10−1.11−1.11−1.11−1.11−1.11−1.12−1.12−1.12−1.12−1.12−1.12−1.12−1.12−1.13−1.13−1.13−1.13−1.13−1.13−1.14−1.14−1.15−1.15−1.15−1.15−1.16−1.16−1.16−1.16−1.17−1.17−1.17−1.17−1.18−1.18−1.18−1.18−1.19−1.19−1.19−1.19−1.20−1.21−1.21−1.21−1.22−1.22−1.22−1.24−1.24−1.26−1.26−1.27−1.27−1.27−1.29−1.29−1.30−1.30−1.31−1.31−1.31−1.36−1.38−1.39−1.39−1.40−1.41−1.41−1.42−1.46−1.48−1.50−1.67−2.25

Signal to noise

Figure 1: Heat map of the top 100 differentially expressed genes between advanced and early atherosclerosis (100 upregulated genes and 100downregulated genes). Red: upregulation; purple: downregulation.

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modules A, B, and C were inferred from upregulated geneswhile modules D, E, and F were inferred from downreg-ulated genes, and the functional annotation of the genesinvolved in the modules was analyzed (as shown in Figure 2).Enrichment analysis showed that the genes in module weremainly associated with chemokine signaling pathway, cellcycle, B cell receptor signaling pathway focal adhesion, andregulation of actin cytoskeleton. Those genes involved ininferred modules were listed in Table 5.

3.4. Pathways Interrelation Analysis. In order to investigatethe involved interrelation between the pathways unidentifiedbefore, modules inferred from the network were analyzedand the interrelation between pathways and genes involvedwas drawn as shown in Figure 3. Modules with highestMCODE score were selected where for module A inferredfrom upregulated DEGs and module D from downregulatedDEGs (Figure 2) pathways interrelation analysis was con-ducted. As shown in Figure 3(a), these genes from moduleA mainly are involved in four pathways that were NF-kappa B signaling pathway, chemokine signaling pathway,legionellosis signaling pathway (with Salmonella infection,interleukin 17 (IL-17), tumor necrosis factor (TNF), epithelialcell, and rheumatoid arthritis (RA) signaling pathway assubgroups), and Staphylococcus aureus infection signalingpathway. C-X-C motif chemokine ligand 2 (CXCL2), C-X-Cmotif chemokine ligand 3 (CXCL3), C-X-Cmotif chemokineligand 8 (CXCL8), and C-X-C motif chemokine ligand 12(CXCL12) took part in three pathways which were NF-kappa B signaling pathway, chemokine signaling pathway,and legionellosis signaling pathway (nodes in three colors).C-Cmotif chemokine ligands 19 and 21 (CCL19, CCL21) wereinvolved in NF-kappa B and chemokine signaling pathwaywhile C-C motif chemokine ligand 5 (CCL5), C-C motifchemokine ligand 20 (CCL20), C-X-C motif chemokineligand 1 (CXCL1), and C-X-C motif chemokine ligand 1(CXCL3) played a role in both legionellosis and chemokinesignaling pathway. Besides, Complement C3 (C3) partici-pated in legionellosis and Staphylococcus aureus infection sig-naling pathway. Pathway and gene set were listed in Table 6.Analysis of module D demonstrated that these genes weremainly involved in focal adhesion (with regulation of actincytoskeleton, platelet activation, and long-term potentiationas subgroups), adherens junction (with glioma, melanomasignaling pathways as subgroups), pathogenic Escherichia coliinfection, and mRNA surveillance pathway (with adrener-gic signaling in cardiomyocytes, oocytes meiosis signalingpathway as subgroups). Among these genes, RHOA tookin 5 pathways that were pathogenic Escherichia coli infec-tion, vascular smooth muscle contraction, focal adhesion,adherens junction, and mRNA surveillance pathway. Raf-1protooncogene and serine/threonine kinase (RAF1) partici-pate in 4 pathways. Protein phosphatase 2 catalytic subunitbeta (PPP2CB), protein phosphatase 2 regulatory subunit B(B56) alpha isoform (PPP2R5A), protein phosphatase 2 reg-ulatory subunit B (B56) gamma isoform (PPP2R5C), proteinphosphatase 1 catalytic subunit beta (PPP1CB), insulin-likegrowth factor 1 receptor (IGF1R) and cytochrome C, somatic

(CYCS), participate in 3 pathways. Ras homolog enrichedin brain (RHEB), protein phosphatase 3 catalytic subunitbeta (PPP3CB), epidermal growth factor receptor (EGFR),smoothmuscle gamma-actin (ACTG2), Vinculin (VCL), andprotein phosphatase 1 regulatory subunit 12A (PPP1R12A)took part in 2 pathways. Pathway and gene set were listed inTable 7.

4. Discussion

The underlying cause of the cardiovascular event is ath-erosclerosis, a chronic inflammatory disease [7]. Profoundlyunderstanding the molecular mechanism of atherosclerosiswas critically important for diagnosis and treatment of car-diovascular disease. Since microarray and high-throughputsequencing provided thousands of gene expression datatypes, it has been widely used to predict the potentialtherapeutic targets for atherosclerosis. In the present study,GSE28829 was analyzed and the total differentially expressedgenes were identified between early and advanced plaquecollected from patients. Functional annotation demonstratedthat these DEGs were mainly involved in osteoclast differ-entiation, cytokine-cytokine receptor interaction, chemokinesignaling pathway, lysosome and Staphylococcus aureusinfection, focal adhesion, regulation of actin cytoskeleton,arrhythmogenic right ventricular cardiomyopathy (ARVC),oxytocin signaling pathway, and cGMP-PKG signaling path-way.

Cross-talks between the vascular and immune systemplay a critical role in atherosclerosis. It is a key point that newdrug development should not be focused on cardiovascularsystem only; the immune system is the potential target for thetreatment of atherosclerosis either. The osteoclast-associatedreceptor (OSCAR), originally described in bone as immuno-logical mediator and regulator of osteoclast differentiation,may be involved in cell activation and inflammation duringatherosclerosis [8]. Cytokine interactions mainly involvedinterleukins (IL), transforming growth factors (TGF), inter-ferons (IFN), and tumor necrosis factors (TNF) [9, 10].CCL2, CCL5, IFN-𝛾, and TNF-𝛼 participate in the monocyterecruitment. IFN-𝛾, IL-1𝛽, TGF-𝛽, and TNF-𝛼 take part inplaque stability. IFN-𝛾, IL-1𝛽, IL-6, IL-12, IL-33, and M-CSFare involved in lesion formation. These signaling pathwaysbut also those identified in this study are well documentedwhere these cytokine targeted therapies use antibodies toblock and inhibit proinflammatory cytokine signaling inorder to dampen the inflammatory response observed inatherosclerotic lesions [11]. In this study, signal to noisemethod implanted in the Morpheus was used to identify theDEGs where this method could get most number of DEGs. Inorder to better understand the interaction of DEGs, GO andKEGG analysis were performed.

The GO term analysis revealed that the upregulatedgenes were mainly involved in immune system process,defense response, and regulation of immune system process(Table 3). These results showed that, as atherosclerosis devel-oped, immune system cells activated and gathered in theplaque [12–14].Downregulated genesweremainly involved in

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C5AR1 CXCR4

CXCL1

CXCL3

CCL19

ADORA3ADCY4

ADCY3

RGS10

CXCL2

ADRA2A

FPR3

CCR1

CCL21

CCL5

CCL16C3AR1

CCR7P2RY13

IL8CCR2

CCL20

RGS19

RGS1

C3

CXCL12

LPAR5

CXCL16

GPR18

PENK

CCR5

PNOC

(a)

CCL4IRF5

HLA-B IRF7

IRF8PTAFR

IRF1HLA-C

HLA-APML

CIITA

IRF4

UBE2CTYMS

PTTG1MCM4

CDK1

AURKA

TOP2A

CCNB2CCNB1

CKS2

KIF20ACCNA2KIF4A

NUSAP1TTK

KNTC1RCC2

MLF1IPCASC5

ZWINTCENPK

SGOL2

(b)

ANPEP

THY1

ITGAL CD36

CD2

CD14

VWF

MYD88

CASP1

NOD2

ACE

PAG1BLNK

SDC1

PTPRCCD22

TNFSF13BIL2RBCD79A

SYK

CD72

LYNPLCG2

SH3KBP1CDH5

SPI1

PRKCH

NCF1 CYBA

NCF2

RAC2HCK

PIK3CD

PLEK NCF4HCLS1VAV3SHC2

PIK3R5

DAPP1

FCER1G

INPP5DKLRG1

(c)

CCND2

RHEB

TNS1

RRAS

IGF1R

TLN2

RHOQ

EGFRILKAP

LAMA5

LAMC1

PPM1B

ITGB3

RAF1

PPM1A

CAP2

ABL1 RHOA

ACTR3B

ENAH

WDR1DLG1

CYCS

PPP3CBPPP2R5C

PPP2CB

PPP2R5APPP1CB NDE1

CLIP1

NDEL1

PDS5B SKA2

NUDCRANBP2

PAPOLA

SRRM1

HNRNPD

HNRNPU

HNRNPA3

SRSF3

PPP1R12A

SF3B2

SRSF1

MAPRE1CLASP2

PAFAH1B1

ACTG2

CORO1CTUBA4A

CNN1

TPM2

TPM1ACTR3

VCL

(d)

GNB5

S1PR3

FGF13

ROCK2

KALRN

ERBB2

MAPK9

ROCK1

HSP90AB1

SMAD4

CRK

FGFR1STK11

FRK

DLG3

PPM1KMAP3K7

CASK

MPP7

ZAK

MPP6

ROR1

RAP1APRKAR1A

ADCY5

PDE3A

PDE4D

ADCY2

ADCY9

PDE8B

PTGER3

GNAS

ITGA7

PARVA

COL4A5ITGA11

ITGA9ITGA8

KAT7

ACTN2

DNAJB6DNAJB5

CYFIP2

DNAJA4

SUGT1

ITGB1

DNAJC10 HSPA4L

ACTA2

HSPA4

YWHAZ

DNAJB4H2AFV

YAP1

CCND1

PGR

CEP70

CEP63

PCM1

(e)

TAGLN

CALD1

MYLKLMOD1

ACTN1

PLS3

DSTN

ITGB5

MYH11

SORBS1WASL

CFL2

PFN2

RHOB

PTPN11

JAK2

FGF2

(f)

Figure 2: Top 6 modules from the protein-protein interaction network. (a) module 1; (b) module 2; (c) module 3; (d) module 4; (e) module5; (f) module 6.

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Table 4: KEGG pathways enrichment analysis in networks.

Expression #Pathway ID Pathway description Observed gene count False discovery rate

Upregulated

4380 Osteoclast differentiation 47 6.30𝐸 − 22

4060 Cytokine-cytokine receptor interaction 63 6.90𝐸 − 18

4062 Chemokine signaling pathway 51 6.91𝐸 − 18

4142 Lysosome 41 1.75𝐸 − 17

5150 Staphylococcus aureus infection 27 2.52𝐸 − 17

Downregulated

4510 Focal adhesion 38 3.66𝐸 − 07

4810 Regulation of actin cytoskeleton 37 1.46𝐸 − 06

5412 Arrhythmogenic right ventricular cardiomyopathy (ARVC) 20 1.52𝐸 − 06

4921 Oxytocin signaling pathway 30 1.58𝐸 − 06

4022 cGMP-PKG signaling pathway 30 1.95𝐸 − 06

CCL20

ADCY4

Legionellosis

Salmonella infection

IL-17 signaling pathway

TNF signaling pathway

Epithelial cell signaling in

Rheumatoid arthritis

C3Staphylococcusaureus infection

FPR3

C3AR1C5AR1

NF-kappa Bsignaling pathway

CXCL1

CXCL8CXCL3

CXCL2

Chemokinesignaling pathway

interactionCytokine-cytokine receptor

CCL19CCL21

CCR2

CCR5

CCR1

CCL16

ADCY3

CXCR4

CXCL16

CCR7

CCL5

CXCL12

Helicobacter pylori infection

(a)

RHEB

PPP3CB

TPM2

TPM1

SRRM1

ABL1PPP1CB

TUBA4A

RHOA

CYCSLAMA5EGFR

Glioma

Melanoma

Colorectal cancer

Long-term potentiation

Long-term depression

AMPK signaling pathway

Oocyte meiosis

Sphingolipid signaling pathway

Adrenergic signaling incardiomyocytes

Platelet activation

Regulation of actin cytoskeleton

CCND2

ENAH

LAMC1ACTG2

RRAS

PPP1R12A

TLN2

ITGB3

VCL

RAF1

IGF1R

PPP2CB

PPP2R5APAPOLA

PPP2R5C

Focal adhesion

Pathogenic

mRNA surveillancepathway

Escherichia coliinfectionAdherens junction

Vascular smoothmuscle contraction

(b)

Figure 3: Interrelation between pathways. (a) Interrelation inferred from module A. (b) Interrelation inferred from module D.

cytoskeleton organization, cellular component organization,and positive regulation of cellular process and confirm therecent findings [15–17] (Table 3). Besides, as shown inTable 4,the KEGG analysis showed that upregulated genes partici-pate in osteoclast differentiation [18–20], cytokine-cytokinereceptor interaction [21], and chemokine signaling pathway[22–24]. Downregulated genes took part in focal adhe-sion [25–27], regulation of actin cytoskeleton [27–29], andarrhythmogenic right ventricular cardiomyopathy (ARVC)[30].These pathways demonstrated promising targets for newdrugs intervention. It is important to keep in mind that theupstream or the key node gene might not be the appropriate

target for drug design because of the core effects and far-range effects especially the side effects that prevent the furtherapplication of the drugs. These GO term and KEGG analysesindicated the possible direction of experimental validation.

Next, the protein-protein interaction (PPI) network wasevaluated and top degree hub genes were listed: ubiquitinA-52 residue ribosomal protein fusion product 1 (UBA52),ribosomal protein L38 (RPL38), integrin subunit alpha L(ITGAL), intercellular adhesion molecule 1 (ICAM1), inter-leukin 7 receptor (IL7R), interleukin 7 (IL7), REL pro-tooncogene, NF-KB subunit (REL) and NF-KB inhibitoralpha (NFKBIA), Vav guanine nucleotide exchange factor

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Table 5: Top 6 modules from protein-protein interaction network.

Gene set MCODE score Nodes

Chemokine signaling pathway 31.419CCL20, PNOC, PENK, LPAR5, C5AR1, CCR1, RGS1, ADRA2A, CXCL3, CXCL2,CCL21, CCR7, CCL19, FPR3, CCR5, CCL5, CXCL16, ADCY3, P2RY13, ADORA3,CCL16, IL8, RGS10, RGS19, CXCL1, C3, CCR2, C3AR1, CXCL12, GPR18, CXCR4,

ADCY4

Cell cycle 10.303KIF20A, PTTG1, HLA-B, CDK1, CASC5, IRF8, IRF4, CIITA, CKS2, IRF5, IRF1,

IRF7, CCL4, UBE2C, KIF4A, CCNA2, AURKA, ZWINT, TOP2A, HLA-A, PTAFR,TYMS, CENPK, CCNB1, MLF1IP, HLA-C, NUSAP1, KNTC1, SGOL2, MCM4,

PML, RCC2, CCNB2, TTK

B cell receptor signaling pathway 9.762

VWF, NCF4, SH3KBP1, PLEK, CD14, TNFSF13B, CD79A, BLNK, CD72, SPI1,PTPRC, KLRG1, IL2RB, PIK3CD, SYK, VAV3, CASP1, CDH5, PLCG2, FCER1G,SDC1, NCF1, INPP5D, PIK3R5, RAC2, CD22, NCF2, LYN, ACE, CYBA, DAPP1,ITGAL, HCLS1, MYD88, PRKCH, PAG1, ANPEP, CD36, THY1, SHC2, NOD2,

HCK, CD2

Focal adhesion 8.852

TNS1, DLG1, NDE1, PPM1B, WDR1, RRAS, ITGB3, CNN1, SRSF1, CCND2,HNRNPD, IGF1R, TPM1, TPM2, EGFR, RHEB, TLN2, HNRNPU, PDS5B, SKA2,NUDC, PAFAH1B1, RHOQ, ABL1, CAP2, ACTG2, PPP3CB, TUBA4A, CORO1C,PAPOLA, RAF1, LAMA5, SF3B2, LAMC1, MAPRE1, ILKAP, RHOA, NDEL1,SRRM1, SRSF3, PPM1A, PPP2R5A, PPP1R12A, PPP1CB, ACTR3B, HNRNPA3,CYCS, ENAH, CLIP1, CLASP2, PPP2CB, RANBP2, PPP2R5C, VCL, ACTR3

Focal adhesion 7.414

YWHAZ, ITGA11, GNB5, KALRN, ROCK1, DNAJB4, SMAD4, S1PR3, DNAJC10,ITGB1, DNAJB6, ITGA8, ERBB2, FGF13, PDE4D, GNAS, PRKAR1A, CYFIP2,

FRK, DNAJB5, CCND1, CASK, CRK, ADCY9, DLG3, HSPA4, HSPA4L, ADCY5,H2AFV, PDE3A, YAP1, PGR, MPP7, ITGA9, ROCK2, PDE8B, PCM1, PARVA,

ADCY2, RAP1A, KAT7, ITGA7, DNAJA4, MAPK9, ACTN2, ZAK, CEP70, CEP63,PPM1K, MAP3K7, MPP6, COL4A5, HSP90AB1, SUGT1, STK11, PTGER3, FGFR1,

ACTA2, ROR1

Regulation of actin cytoskeleton 6.25 CALD1, PLS3, FGF2, TAGLN, RHOB, CFL2, MYLK, ITGB5, WASL, JAK2, LMOD1,DSTN, PFN2, MYH11, ACTN1, PTPN11, SORBS1

1 (VAV1), and lymphocyte cytosolic protein 2 (LCP2). Themost significant hub gene in the network is UBA52. UBA52regulates ubiquitination of ribosome and sustains embryonicdevelopment [31]. RPL38 takes part in RNA binding [32] andconstructing ribosome [33]. ITGAL contributes to naturalkiller cell cytotoxicity [34], involved in leukocyte adhesionand transmigration of leukocytes [35]. ICAM1 acts as a recep-tor for major receptor group rhinovirus A-B capsid proteins[36, 37]. As Kaposi’s sarcoma-associated herpesvirus/HHV-8 infection, ICAM1 is degraded by viral E3 ubiquitin lig-ase MIR2, presumably to prevent lysis of infected cells bycytotoxic T-lymphocytes and NK cell [38]. IL7R, a secretedprotein, is not only the receptor of interleukin 7 (IL7) but alsothe receptor for thymic stromal lymphopoietin (TSLP). IL7stimulates the proliferation of lymphoid progenitor cells andB cell maturation [39–42]. REL plays a role in differentiationand lymphopoiesis that formed heterodimer (or homodimer)to help translocation of NF-kappa B [43, 44]. Interestingly,the inhibitor of NF-kappa B complex translocation, NFKBIA,was induced either, where this gene traps the REL dimersin cytoplasm by masking the nuclear translocation signals[45, 46]. VAV1 is another critical transducer of T cell receptorsignals to the calcium and extracellular signal-regulatedkinases (ERK) pathways [47, 48]. Lastly, LCP2 is involved in T

cell antigen receptor mediated signaling [47]. In conclusion,these hub genes are mainly involved in immune systemscells recruitment in the plaque, such as T cells and B cellsgathering.

PPI network analysis demonstrated that both up- anddownregulated genes interacted directly or indirectly. Themore edges associated with genes indicated the more poten-tial selection for the targets. Given the fact that PPI is consid-ered a new type of targets, appropriate methods for screen-ing are pivotal for drug development. Forster resonanceenergy transfer (FRET) and fluorescence lifetimemicroscopy(FLIM) are useful cell-based methods for high-throughputscreening (HTS). Based on our findings, expression vectorsof interactive protein can be constructed for drug screening.For example, REL and NFKBIA can be cotransfected intocells and screen the molecules that inhibit or activate theinteraction between the proteins.

Module analysis of the PPI network showed thatthe development of atherosclerosis was associated withchemokine signaling pathway, cell cycle, B cell receptorsignaling pathway, focal adhesion, and regulation of actincytoskeleton. Indeed, kinds of chemokines were secretedand trapped different types of immune cells to the arterialplaque [49, 50]. As atherosclerosis developed, the immune

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Table 6: KEGG analysis based on module A.

GOID GO term Ontology source Term 𝑃 value Nr. genes Associated genes found

GO:0004064 NF-kappa B signalingpathway KEGG 01.03.2017 19.0𝐸 − 6 5.00 [CCL19, CCL21, CXCL12,

CXCL2, CXCL8]

GO:0005150 Staphylococcus aureusinfection KEGG 01.03.2017 43.0𝐸 − 6 4.00 [C3, C3AR1, C5AR1, FPR3]

GO:0004060 Cytokine-cytokinereceptor interaction KEGG 01.03.2017 37.0𝐸 − 18 16.00

[CCL16, CCL19, CCL20,CCL21, CCL5, CCR1,CCR2, CCR5, CCR7,

CXCL1, CXCL12, CXCL16,CXCL2, CXCL3, CXCL8,

CXCR4]

GO:0004062 Chemokine signalingpathway KEGG 01.03.2017 10.0𝐸 − 24 18.00

[ADCY3, ADCY4, CCL16,CCL19, CCL20, CCL21,

CCL5, CCR1, CCR2, CCR5,CCR7, CXCL1, CXCL12,CXCL16, CXCL2, CXCL3,

CXCL8, CXCR4]

GO:0004657 IL-17 signaling pathway KEGG 01.03.2017 17.0𝐸 − 6 5.00 [CCL20, CXCL1, CXCL2,CXCL3, CXCL8]

GO:0004668 TNF signaling pathway KEGG 01.03.2017 35.0𝐸 − 6 5.00 [CCL20, CCL5, CXCL1,CXCL2, CXCL3]

GO:0005120Epithelial cell signalingin Helicobacter pylori

infectionKEGG 01.03.2017 1.7𝐸 − 3 3.00 [CCL5, CXCL1, CXCL8]

GO:0005132 Salmonella infection KEGG 01.03.2017 230.0𝐸 − 6 4.00 [CXCL1, CXCL2, CXCL3,CXCL8]

GO:0005134 Legionellosis KEGG 01.03.2017 1.2𝐸 − 6 5.00 [C3, CXCL1, CXCL2,CXCL3, CXCL8]

GO:0005323 Rheumatoid arthritis KEGG 01.03.2017 14.0𝐸 − 6 5.00 [CCL20, CCL5, CXCL1,CXCL12, CXCL8]

system offers a large variety of immune checkpoint proteins;both costimulatory and inhibitory proteins are involved.Costimulatory proteins can promote cell survival, cell cycleprogression, and differentiation to effector andmemory cells,whereas inhibitory proteins terminate these processes to haltongoing inflammation [51]. Studies showed that B1 cellscan prevent lesion formation, whereas B2 cells have beensuggested to promote it [52, 53]. These activated signalingpathways are key to the development of atherosclerosis; it sug-gested the promising candidates for therapeutic intervention.

Interrelation between pathway showed that cross-talkarises through genes participating in different signalingpathways. It was suggested that these genes might be used astargets for intervention.

Liver X receptors (LXRs), as a promising target, pre-venting the development of atherosclerosis, attracted muchmore attention during these years. Both activators of LXR𝛼and LXR𝛽 presented preferable effects in preclinical practicebut due to unclarified mechanism, these activators alwaysinduce adverse neurological events [54, 55]. Analysis ofinterrelation between pathways suggested that the fact thatthe cross-talk might be beneficial or detrimental for the

ultimate clinical goal should be taken much more intoconsideration.

5. Conclusion

All these results in this study inspired that immune systemand inflammation progress are the promising targets forprevention of atherosclerosis besides lipid lowering andcholesterol metabolism regulation. In fact, immune systemdisorders are the physiological and pathological basis ofmany diseases, including angiocardiopathy [56–59]. Our dataprovides a comprehensive bioinformatics analysis of DEGsthat might be involved in the development of atheroscle-rosis. Those genes and signaling pathway identified in thisstudy implied further application for clinical use. However,molecular biological experiments are required to confirm thefunction of the identified genes in atherosclerosis.

Conflicts of Interest

The authors declare that there are no conflicts of interest.

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Table 7: KEGG analysis based on module D.

GOID GO term Ontology source Term 𝑃 value Nr. genes Associated genes found

GO:0005130 Pathogenic Escherichiacoli infection KEGG 01.03.2017 3.6𝐸 − 3 3.00 [ABL1, RHOA, TUBA4A]

GO:0004071 Sphingolipid signalingpathway KEGG 01.03.2017 500.0𝐸 − 6 5.00 [PPP2CB, PPP2R5A,

PPP2R5C, RAF1, RHOA]

GO:0004270 Vascular smooth musclecontraction KEGG 01.03.2017 570.0𝐸 − 6 5.00 [ACTG2, PPP1CB,

PPP1R12A, RAF1, RHOA]

GO:0005210 Colorectal cancer KEGG 01.03.2017 4.6𝐸 − 3 3.00 [CYCS, RAF1, RHOA]

GO:0004270 Vascular smooth musclecontraction KEGG 01.03.2017 570.0𝐸 − 6 5.00 [ACTG2, PPP1CB,

PPP1R12A, RAF1, RHOA]

GO:0004510 Focal adhesion KEGG 01.03.2017 560.0𝐸 − 12 12.00

[CCND2, EGFR, IGF1R,ITGB3, LAMA5, LAMC1,PPP1CB, PPP1R12A, RAF1,

RHOA, TLN2, VCL]

GO:0004611 Platelet activation KEGG 01.03.2017 610.0𝐸 − 6 5.00 [ITGB3, PPP1CB,PPP1R12A, RHOA, TLN2]

GO:0004720 Long-term potentiation KEGG 01.03.2017 6.3𝐸 − 3 3.00 [PPP1CB, PPP3CB, RAF1]

GO:0004810 Regulation of actincytoskeleton KEGG 01.03.2017 2.1𝐸 − 6 9.00

[EGFR, ENAH, ITGB3,PPP1CB, PPP1R12A, RAF1,

RHOA, RRAS, VCL]

GO:0005210 Colorectal cancer KEGG 01.03.2017 4.6𝐸 − 3 3.00 [CYCS, RAF1, RHOA]

GO:0004071 Sphingolipid signalingpathway KEGG 01.03.2017 500.0𝐸 − 6 5.00 [PPP2CB, PPP2R5A,

PPP2R5C, RAF1, RHOA]

GO:0004152 AMPK signalingpathway KEGG 01.03.2017 570.0𝐸 − 6 5.00

[IGF1R, PPP2CB,PPP2R5A, PPP2R5C,

RHEB]

GO:0004520 Adherens junction KEGG 01.03.2017 700.0𝐸 − 6 4.00 [EGFR, IGF1R, RHOA,VCL]

GO:0004730 Long-term depression KEGG 01.03.2017 4.6𝐸 − 3 3.00 [IGF1R, PPP2CB, RAF1]

GO:0005214 Glioma KEGG 01.03.2017 5.6𝐸 − 3 3.00 [EGFR, IGF1R, RAF1]

GO:0005218 Melanoma KEGG 01.03.2017 6.9𝐸 − 3 3.00 [EGFR, IGF1R, RAF1]

GO:0003015 mRNA surveillancepathway KEGG 01.03.2017 10.0𝐸 − 6 6.00

[PAPOLA, PPP1CB,PPP2CB, PPP2R5A,PPP2R5C, SRRM1]

GO:0004071 Sphingolipid signalingpathway KEGG 01.03.2017 500.0𝐸 − 6 5.00 [PPP2CB, PPP2R5A,

PPP2R5C, RAF1, RHOA]

GO:0004114 Oocyte meiosis KEGG 01.03.2017 63.0𝐸 − 6 6.00[IGF1R, PPP1CB, PPP2CB,

PPP2R5A, PPP2R5C,PPP3CB]

GO:0004152 AMPK signalingpathway KEGG 01.03.2017 570.0𝐸 − 6 5.00

[IGF1R, PPP2CB,PPP2R5A, PPP2R5C,

RHEB]

GO:0004261 Adrenergic signaling incardiomyocytes KEGG 01.03.2017 140.0𝐸 − 6 6.00

[PPP1CB, PPP2CB,PPP2R5A, PPP2R5C,

TPM1, TPM2]

GO:0004730 Long-term depression KEGG 01.03.2017 4.6𝐸 − 3 3.00 [IGF1R, PPP2CB, RAF1]

GO:0005210 Colorectal cancer KEGG 01.03.2017 4.6𝐸 − 3 3.00 [CYCS, RAF1, RHOA]

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Authors’ Contributions

Xiaowen Tan and Xiting Zhang contributed equally to thiswork.

Acknowledgments

This work is supported by grants from National NaturalScience Foundation of China (no. 81403132), China Ministryof Science and Technology (no. 2014CB542902), and TianjinMunicipal Education Commission (no. 20140203).

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