Bioinformatic Gene Analysis for Potential Biomarkers And
Total Page:16
File Type:pdf, Size:1020Kb
Zou et al. J Transl Med (2019) 17:45 https://doi.org/10.1186/s12967-019-1790-x Journal of Translational Medicine RESEARCH Open Access Bioinformatic gene analysis for potential biomarkers and therapeutic targets of atrial fbrillation-related stroke Rongjun Zou1†, Dingwen Zhang1†, Lei Lv1†, Wanting Shi2, Zijiao Song3, Bin Yi1, Bingjia Lai4, Qian Chen5, Songran Yang6,7* and Ping Hua1* Abstract Background: Atrial fbrillation (AF) is one of the most prevalent sustained arrhythmias, however, epidemiological data may understate its actual prevalence. Meanwhile, AF is considered to be a major cause of ischemic strokes due to irregular heart-rhythm, coexisting chronic vascular infammation, and renal insufciency, and blood stasis. We studied co-expressed genes to understand relationships between atrial fbrillation (AF) and stroke and reveal potential biomarkers and therapeutic targets of AF-related stroke. Methods: AF-and stroke-related diferentially expressed genes (DEGs) were identifed via bioinformatic analysis Gene Expression Omnibus (GEO) datasets GSE79768 and GSE58294, respectively. Subsequently, extensive target prediction and network analyses methods were used to assess protein–protein interaction (PPI) networks, Gene Ontology (GO) terms and pathway enrichment for DEGs, and co-expressed DEGs coupled with corresponding predicted miRNAs involved in AF and stroke were assessed as well. Results: We identifed 489, 265, 518, and 592 DEGs in left atrial specimens and cardioembolic stroke blood samples at < 3, 5, and 24 h, respectively. LRRK2, CALM1, CXCR4, TLR4, CTNNB1, and CXCR2 may be implicated in AF and the hub- genes of CD19, FGF9, SOX9, GNGT1, and NOG may be associated with stroke. Finally, co-expressed DEGs of ZNF566, PDZK1IP1, ZFHX3, and PITX2 coupled with corresponding predicted miRNAs, especially miR-27a-3p, miR-27b-3p, and miR-494-3p may be signifcantly associated with AF-related stroke. Conclusion: AF and stroke are related and ZNF566, PDZK1IP1, ZFHX3, and PITX2 genes are signifcantly associated with novel biomarkers involved in AF-related stroke. Keywords: Gene analysis, Biomarkers, Atrial fbrillation-related stroke Background 80-years-of-age [1, 2]. However, epidemiological data Atrial fbrillation (AF) is one of the most prevalent may understate its actual prevalence, because 40% of sustained arrhythmias, having an age-adjusted hospi- patients are asymptomatic and remain undiagnosed with talization incidence of 1–4% of the general population subclinical AF [3]. Tere is also evidence that patients and an prevalence rising of > 13% for those older than with AF have signifcantly increased cardiovascular- related morbidity, given its association with atrial and ventricular mechanical or electrical failure, structural *Correspondence: [email protected]; [email protected] †Rongjun Zou, Dingwen Zhang and Lei Lv contributed equally to this and hemodynamic alterations, and thromboembolic article events [3]. 1 Department of Cardio-Vascular Surgery, Sun Yat-sen Memorial Hospital, Stroke is the leading cause of disability and death and Sun Yat-sen University, Guangzhou 510120, China 6 The Biobank of Sun Yat-sen Memorial Hospital, Sun Yat-sen University, has an estimated incidence of 3.73 (95% CI 3.51–3.96) Guangzhou 510120, China per 1000 person-years among black- and white- adults in Full list of author information is available at the end of the article an atherosclerosis risk in communities (ARIC) cohort [4]. © The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creat iveco mmons .org/licen ses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creat iveco mmons .org/ publi cdoma in/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Zou et al. J Transl Med (2019) 17:45 Page 2 of 12 Furthermore, global increases in stroke prevalence plus Methods stroke-related disability and mortality associated with Materials and methods aging will increase [5, 6]. Tus, we may not now know the GSE79768 and GSE58294 datasets were downloaded actual true burden of stroke due to limits in brain imag- from GEO (http://www.ncbi.nlm.nih.gov/geo/) [13] and ing identifcation in < 10 mm small hypointense areas and expression profling arrays were generated using GPL570 silent infarctions for 28% of those patients older than (HG-U133_Plus_2) Afymetrix Human Genome U133 65-years-of-age [7]. AF is commonly classifed as parox- Plus 2.0 Array (Afymetrix, Santa Clara, CA). Addition- ysmal, persistent or permanent, or new onset arrhythmia ally, the GSE79768 dataset, including 26 specimens with basing on the present continuous time, which mainly paired left atrial (LA) and right atrial (RA) tissue obtained included that paroxysmal AF was self-terminates within from 13 patients was used to identify diferential LA- 7 days, while persistent AF was lasts longer than 7 days or to-RA gene expression and molecular mechanisms needs cardioversion, and usually has lasted for 3 months for patients with persistent AF or sinus rhythm (SR) [8]. As we all kwon, AF is considering to be a major cause abnormalities and we describe potential mechanisms of of ischemic strokes due to irregular heart-rhythm, coex- AF-related remodeling in the LA and the relationship isting chronic vascular infammation, and renal insuf- between LA arrhythmogenesis and thrombogenesis. In fciency, and blood stasis. According to Rivaroxaban this study, persistent AF patients has lasts continuously Once Daily Oral Direct Factor Xa Inhibition Compared for > 6 months, while the SR patients had no evidence of With Vitamin K Antagonism for Prevention of Stroke AF clinically and any anti-arrhythmic drug history. Blood and Embolism Trial in Atrial Fibrillation (ROCKET-AF) samples of GSE58294 were collected from cardioembolic trial study, Steinberg et al. [9] suggested that the par- stroke (N = 69) and control patents (N = 23) at < 3, 5, and oxysmal AF patients carrying a lower adjusted rate of 24 h. stroke or systemic embolism (adjusted HR: 0.78, 95% CI Data processing 0.61–0.99, P = 0.045), all-cause mortality (adjusted HR: 0.79, 95% CI 0.67–0.94, P = 0.006), and the composite of R packages of “afy”, “afyPLM”, and “limma” (http://www. stroke or systemic embolism or death (adjusted HR: 0.82, bioco nduct or.org/packa ges/relea se/bioc/html/afy.html), 95% CI 0.71–0.94, P = 0.005) than persistent AF patients provided by a bioconductor project [14], were applied after adjusted efcacy and safety outcomes. According to assess GSE79768 and GSE58294 RAW datasets. We to the Oxford vascular study (OXVASC), nearly 43.9% of used background correction, quantile normalization, ischemic strokes were associated with AF among patients probe summarization and log2-transformation, to create 80 years-of-age or older who had a threefold increase in a robust multi-array average (RMA), a log-transformed AF in the past 3 decades [10]. However, this assumption perfect match, and a mismatch probe (PM and MM) has been challenged by the atrial fbrillation reduction methods. Te Benjamini-Hochberg method was used atrial pacing trial (ASSERT) which identifed a tempo- to adjust original p-values, and the false discovery rate ral association between subclinical AF and stroke risk (FDR) procedure was used to calculate fold-changes (FC). among patients with implantable pacemakers and def- Genes expression values of the|log2 FC| > 1and adjusted brillators. Tey reported that only 8% and 16% of patients p < 0.05 were used for fltering AF-DEGs. However, the had an association between pre-detected and post- |log2 FC| > 1.5 and adjusted p < 0.05 were used to identify detected AF within months of stroke or systemic embo- stroke-DEGs, given that blood sample specifcity pointed lism, respectively [11]. Of note, AF is often intermittent to many genes. Additionally, we calculated and made and asymptomatic, and presents as an electromechani- Venn diagrams for co-DEGs for AF- and stroke-DEGs. cal disassociation of atrial fbrillation. Clinically, current Finally, we applied online prediction tools utilizing stroke risk scores and traditional diagnosis with an elec- microRNA Data Integration Portal (mirDIP) (http:// trocardiogram are practical, while the limitation of pre- ophid .utoro nto.ca/mirDI P) [15], miRDB (http://mirdb dict stroke risk accurately in individual AF patients was .org/) [16], TargetScan (v7.1; http://www.targe tscan .org/ signifcantly identifed, especially in persistent AF which vert_71/) [17], and DIANA Tools (http://diana .imis.athen carrying a higher risk of stroke or systemic embolism a-innov ation .gr/Diana Tools /) [18], to predict poten- and all-cause mortality [12]. In this study, we identifed tial microRNA targeting. Subsequently, we used the co-expressed diferentially expressed genes (co-DEGs) of mirDIP, miRDB, TargetScan, and Diana Tools software persistent AF and stroke and elucidated molecular mech- to predict which of the selected miRNAs could target co- anisms and pathology of AF-related DEGs (AF-DEGs) DEGs. We determined 5 top candidate miRNAs based on and stroke-related DEGs (stroke-DEGs). Finally, we higher predicted scores for ≥ 3 prediction tools for each provide a bioinformatic analysis of DEGs and predicted co-DEG. microRNAs (miRNAs) for AF patients prone to stroke. Zou et al. J Transl Med (2019) 17:45 Page 3 of 12 Identifcation of protein–protein interaction (PPI) networks AF- and stroke-DEGs were confrmed. We found 489 of DEGs DEGs in LA specimens of AF patients compared with PPI networks of AF- and stroke-DEGs were analyzed SR patients, including 428 down-regulated genes and using the search tool for the retrieval of interacting genes 61 up-regulated genes. However, total of 265, 518, and (STRING database, V10.5; http://strin g-db.org/) that 592 DEGs were identifed following the time points of predicted protein functional associations and protein– less than 3, 5, and 24 h after stroke, respectively.