Bioinformatic analysis and in vivo validation of angiogenesis related genes in inflammatory bowel disease

Objectives: Angiogenesis plays a significant role in the occurrence and development of inflammatory bowel disease (IBD). The aim of this study is to explore potential angiogenesis related genes (ARGs) in IBD through bioinformatics analysis and in vivo experiments. Methods: GSE57945, GSE87466, and GSE36807 were obtained from the Gene Expression Omnibus database. GSE57945 was used as the training set, while GSE87466 and GSE36807 were used as the validation set. The key ARGs associated with IBD were identified using the least absolute shrinkage and selection operator (LASSO) and random forest methods. These identified ARGs were then utilized to construct a diagnostic model for IBD. The Single-Sample Genome Enrichment Analysis, Cibersort, and Xcell methods were used to evaluate the immune infiltration. Expression of amyloid beta precursor protein (APP) was verified in the IBD mouse model induced by dextran sulfate sodium using immunohistochemistry (IHC). Results: The receiver operating curve area of GSE57945 was 0.948. Two distinct clusters were identified using consensus clustering and non-negative matrix factorization clustering. Subsequent analyses revealed significant differences in immune levels and functional enrichment between the two clusters. The successful construction of the animal model for the IBD was evident by hematoxylin and eosin staining, while IHC results showed a high expression of APP in IBD and a low expression in normal tissues. Conclusion: Our findings provide new insights into the diagnosis of IBD by ARGs, and APP could be a potential novel biomarker for IBD and promising therapeutic targets.