Objective: Idiopathic interstitial pneumonias (IIPs) are a group of diffuse parenchymal lung diseases of unknown etiology characterized by the presence of various degrees of inflammation and fibrosis. We aimed to screen the differences among IIPs subtypes in the gene level by using the microarray expression profiles of normal lung tissue and IIPs tissue for the key genes associated with early diagnosis and treatment of IIPs.
Methods: The gene expression profile of six kinds of IIPs (GSE 32537) subtypes tissue and normal lung tissues were downloaded. The differentially expressed genes (DEGs) in different IIPs subtypes were selected by using the expression profiling. In addition, the screened DEGs were further analyzed by function annotation, pathway analysis, and interaction network analysis to reveal the differences among these subtypes.
Results: The gene expression analysis showed that nine genes including SERPINA3, IL1R2, CBS, MGAM, SLCO4A1, S100A12, FPR1, SDR16C5, and MT1X in six subtypes of IIPs were significantly increased. There were significant differences in DEGs among six subtypes of IIPs, and the DEGs of some IIPs subtypes involved in immune, inflammatory response and cell adhesion processes. Moreover, the PPI network analysis indicated that SERPINA3 played an important role in the molecular mechanisms of IIPs.
Conclusion: This comprehensive description of altered gene expression in different subtypes of IIPs underscores the complex biological processes characteristic of different subtypes of IIPs and may provide a foundation for future research into this devastating disease.
Keywords: function annotation; idiopathic interstitial pneumonias; overlapping genes; pathway analysis; protein-protein interaction network; subtypes.