Bioinformatics Analysis to Find Novel Biomarkers for Coronary Heart Disease

Abstract

Background: Coronary heart disease (CHD), a major cause of death worldwide, is defined as a narrowing or blockage of the coronary arteries that supply oxygen and blood to the heart. We aimed to find potential biomarkers for coronary artery disease, by comparing the expression profile of blood exosomes of both normal and CHD samples.

Methods: Datasets of 6 CHD and 6 normal samples of blood exosomes were downloaded, and differentially expressed RNAs, with adjusted P<0.01 and log2FoldChange≥1 were achieved. Moreover, gene ontology (GO) and pathway analysis were accomplished by PANTHER database for datasets.

Results: Our data analysis found 119 differentially expressed genes between two datasets. By comparing transcriptome profiles, we candidate the highest downregulated gene, ACSBG1, and the highest upregulated one, DEFA4, as specific biomarkers for CHD. Furthermore, GO and pathway analysis depicted that aforementioned differentially expressed genes are mostly involved in different molecular metabolic process, inflammation, immune system process and response to stimulus pathways which all cause cardiovascular diseases.

Conclusion: We have provided new potential biomarkers for CHD, though experimental validation is still needed to confirm the suitability of the candidate genes for early detection of CHD.

Keywords: Blood exosomes; Coronary heart disease; Differentially expressed genes.

Fig. 1:

Volcano plot shows differentially expressed genes. Red dots indicate differentially expressed genes in which the up-regulated genes with positive logFC were located in upper part of the graph(+0) and the down-regulated genes with negative logFC were mapped to the lower part of the graph(−0). Nonsignificant genes were illustrated in black dots

Fig. 2:

Gene ontology (GO) enrichment analysis of differentially expressed genes. A) Biological process (BP) shows that the majority of the differentially expressed genes involve in biological regulation. B) Cellular component (CC) demonstrates that the genes with differential expression have roles in different cellular processes. C) Molecular function (MF) shows that those genes implicates in binding and catalytic activities

Fig. 3:

Three major parts of biological process are cellular process, response to stimulus, and immune system processes which each has more detailed categories. A)Cellular process demonstares that ACSBG1 gene has an important role in cellular metabolic. B)Response to stimulus reveals that DEFA4 gene has a significant role in response to stress. C)Immune system process shows that ACSBG1 and DEFA4 genes have important roles in immune response

Fig. 4:

The top significant terms pathways enriched differential expressed genes. The largest percentage of the DE genes involve in the inflammation mediated by chemokine and cytokine signaling pathway which is shown in green