Genome-wide Association Studies of the Pathogenic Sphingosine-1-Phosphate Gene in Ulcerative Colitis
Hongyu Chen1, Jingyu Shang1, Song Zhao1
1Department of Gastroenterology, Afffliated Hospital of Nanjing University of Chinese Medicine (JiangSu Province Hospital of Chinese Medicine), Nanjing, China.
Background:
Ulcerative colitis (UC) is a chronic inflammatory bowel disease that can lead to malignancies over time. Sphingosine-1-phosphate (S1P) receptor signaling affects lymphocyte trafficking and vascular integrity, influencing intestinal inflammation. This study aimed to identify S1P-related key genes in UC.
Methods:
Differentially expressed genes (DEGs) between the UC and control groups were analyzed in the GSE87473 (training) dataset. Genes overlapping between the DEGs and S1P-related genes were considered candidate genes. These genes were incorporated into machine learning algorithms and subjected to expression analysis to identify key genes. Gene functions were determined through a gene–gene interaction network, enrichment analysis, and immune cell infiltration analysis. In addition, transcription factor–mRNA and mRNA–miRNA–lncRNA networks were constructed. Finally, reverse transcription–quantitative polymerase chain reaction (RT-qPCR) was performed to evaluate the expression of key candidate genes in UC and control tissues.
Results:
This study identified two key genes (SPHK2 and SPNS2) associated with UC. Notably, SPHK2 expression was lower and SPNS2 expression was higher in the UC group in both training and validation datasets and in clinical UC tissues (RT-qPCR). The area under the curve values of SPHK2 and SPNS2 exceeded 0.7 in both datasets, indicating that the genes had good diagnostic efficacy for UC. Consistently, the nomogram showed that the two genes had promising diagnostic value in UC. SPHK2 and SPNS2 were found to be localized to the plasma membrane. The correlations of the two genes with different immune cells showed significantly opposite trends. In particular, SPHK2 had the strongest positive correlation with M2 macrophages (r = 0.6) and the strongest negative correlation with neutrophils. Moreover, mRNA–miRNA–lncRNA and transcription factor– mRNA networks of the key genes were constructed.
Conclusion:
This study suggests that SPHK2 and SPNS2 are key genes associated with UC, highlighting their potential as effective diagnostic biomarkers.
Related Concept Videos
Genome-wide Association Studies-GWAS
GWAS does not require the identification of the target gene involved in...
Pleiotropy
Pharmacogenomics: Identification of New Drug Targets
Inflammatory Bowel Disease II: Ulcerative Colitis
Pharmacogenetics of Drug Transporters: P-Glycoprotein and Solute Carrier Transporters
Inflammatory Bowel Disease I: Ulcerative Colitis
Inflammatory bowel disease, or IBD, encompasses a group of disorders characterized by chronic inflammation or ulceration of the gastrointestinal tract.
Risk Factors
The exact cause of IBD remains unclear, although it is believed to be due to a mix of genetic, environmental, microbial, and immune factors. Genetic factors are significant in determining susceptibility to IBD, with family history being a critical risk factor. Individuals with a first-degree relative who has IBD are at...
