MicroRNAs: novel biomarkers for gastrointestinal carcinomas.

MicroRNAs (miRNAs) are a class of non-coding small RNAs. They play an important role as a post-transcriptional regulator in the protein synthesis and are involved in cellular processes, such as proliferation, apoptosis, and differentiation. miRNAs give us a new perspective to understand carcinogenesis. Since the high-throughput method developed, the miRNA profiles of cancer tissues have been comprehensively studied and specific miRNAs signatures have been identified as potential biomarkers for cancer diagnosis, therapy effect prediction, and prognosis. Additionally, the exploration in cell-free miRNAs has achieved inspiring results, indicating a more applicable cancer biomarker. We made a review and tried to figure out their potential application as biomarkers in the gastrointestinal carcinomas.