miRNA profiling of esophageal adenocarcinoma using transcriptome analysis.

Esophageal adenocarcinoma (EAC) occurs following a series of histological changes through epithelial-mesenchymal transition (EMT). A variable expression of normal and aberrant genes in the tissue can contribute to the development of EAC through the activation or inhibition of critical molecular signaling pathways. Gene expression is regulated by various regulatory factors, including transcription factors and microRNAs (miRs). The exact profile of miRs associated with the pathogenesis of EAC is largely unknown, though some candidate miRNAs have been reported in the literature. To identify the unique miR profile associated with EAC, we compared normal esophageal tissue to EAC tissue using bulk RNA sequencing. RNA sequence data was verified using qPCR of 18 selected genes. Fourteen were confirmed as being upregulated, which include CDH11, PCOLCE, SULF1, GJA4, LUM, CDH6, GNA12, F2RL2, CTSZ, TYROBP, and KDELR3 as well as the downregulation of UGT1A1. We then conducted Ingenuity Pathway Analysis (IPA) to analyze for novel miR-gene relationships through Causal Network Analysis and Upstream Regulator Analysis. We identified 46 miRs that were aberrantly expressed in EAC compared to control tissues. In EAC tissues, seven miRs were associated with activated networks, while 39 miRs were associated with inhibited networks. The miR-gene relationships identified provide novel insights into potentially oncogenic molecular pathways and genes associated with carcinogenesis in esophageal tissue. Our results revealed a distinct miR profile associated with dysregulated genes. The miRs and genes identified in this study may be used in the future as biomarkers and serve as potential therapeutic targets in EAC.

Transcriptomic changes and gene fusions during the progression from Barrett's esophagus to esophageal adenocarcinoma.

The incidence of esophageal adenocarcinoma (EAC) has surged by 600% in recent decades, with a dismal 5-year survival rate of just 15%. Barrett's esophagus (BE), affecting about 2% of the population, raises the risk of EAC by 40-fold. Despite this, the transcriptomic changes during the BE to EAC progression remain unclear. Our study addresses this gap through comprehensive transcriptomic profiling to identify key mRNA signatures and genomic alterations, such as gene fusions. We performed RNA-sequencing on BE and EAC tissues from 8 individuals, followed by differential gene expression, pathway and network analysis, and gene fusion prediction. We identified mRNA changes during the BE-to-EAC transition and validated our results with single-cell RNA-seq datasets. We observed upregulation of keratin family members in EAC and confirmed increased levels of keratin 14 (KRT14) using immunofluorescence. More differentiated BE marker genes are downregulated during progression to EAC, suggesting undifferentiated BE subpopulations contribute to EAC. We also identified several gene fusions absent in paired BE and normal esophagus but present in EAC. Our findings are critical for the BE-to-EAC transition and have the potential to promote early diagnosis, prevention, and improved treatment strategies for EAC.