A series of microRNA expression signatures may help predict the progression of Barrett's esophagus into esophageal adenocarcinoma, according to a new study in Cancer Prevention Research (March 2013, Vol. 6:3, pp. 196-205).
Esophageal adenocarcinoma, once a rare cancer representing only 5% of all esophageal cancers in the U.S., is the fastest-rising cancer and has increased 600% in the past 30 years, according to the American Association for Cancer Research. It now comprises more than 80% of all new esophageal cancers in the U.S.
To improve survivability, it is best to prevent the progression of esophageal adenocarcinoma from its premalignant lesion, Barrett's esophagus, according to researchers at the University of Texas MD Anderson Cancer Center.
They compared hundreds of microRNAs in normal esophageal epithelia and in Barrett's esophagus and esophageal adenocarcinoma tissues of different histological grades with distinct progression risks. As a result, they were able to identify a number of differentially expressed microRNAs at each histological stage.
The expression of microRNAs in Barrett's esophagus and esophageal adenocarcinoma tissues were similar, indicating that the microRNA aberrations were early events in the development of Barrett's esophagus, the researchers reported.
They also identified a small number of microRNAs that were significantly different between Barrett's esophagus and esophageal adenocarcinoma. Patients with Barrett's esophagus with low levels of miR-375 and/or high levels of the other five microRNAs who are upregulated in esophageal adenocarcinoma are at increased risk for malignant progression and should be under intensive surveillance, screening, and treatment of their Barrett's esophagus, the researchers said.
Defining the protein-coding genes targeted by the differentially expressed microRNAs may provide significant biological insights into the development of esophageal adenocarcinoma, they found. The genes may become promising biomarkers to predict Barrett's esophagus progression and potential preventive and therapeutic targets, the study authors concluded.