mRNA and lncRNA Expression Profiling of Radiation-Induced Gastric Injury Reveals Potential Radiation-Responsive Transcription Factors

Radiation-induced gastric injury is a serious concern that may limit the duration and the delivered dose of radiation. However, the genome-wide molecular changes in stomach upon ionizing radiation have not been reported. In this study, mouse stomach was irradiated with 6 or 12 Gy X-ray irradiation and we found that radiation resulted in the atrophy of gastric mucosa and abnormal morphology of chief and parietal cells. Radiation-induced gastric injury was accompanied by an increase in the serum levels of pepsinogen A and pepsinogen C but not gastrin-17. The expression profiles of messenger RNA (mRNA) and long noncoding RNA (lncRNA) in normal and irradiated gastric tissues were measured by microarray analysis. Results revealed 17 upregulated and 10 downregulated mRNAs were consistent in 6 and 12 Gy irradiated gastric tissues, including D site-binding protein (Dbp) and fibrinogen-like protein 1 (Fgl1). Thirteen upregulated and 96 downregulated lncRNAs were commonly changed in 6 and 12 Gy irradiated gastric tissues. The dysregulated mRNAs were implicated in multiple pathways and showed coexpression with lncRNAs. To identify motifs for transcription factors and coactivators in the proximal promoter regions of the dysregulated RNAs, the bioinformatic tool Biopython was used. A variety of common motifs that are associated with transcription factors were identified, including ZNF263, LMX1B, and Dlx1. Our findings illustrate the molecular changes during radiation-induced gastric injury and the potential transcription factors driving this alteration.