MicroRNA Dysregulation in Esophageal Neoplasia: The Biological Rationale for Novel Therapeutic Options

While the phenotypic changes involved in the esophageal oncogenic “cascade” are now well established, the molecular profiling of this pathway remains unreliable. Our understanding of the molecular dysregulations underlying the development/progression of cancer has recently been expanded by the characterization of a new class of small, noncoding RNA gene products, the microRNAs (or miRNAs). These “endogenous silencers” target a large number of genes, functioning as tumor suppressors or tumor promoters, depending on the activity of the targeted genes. In esophageal cancer, miRNA dysregulation plays a significant part in the molecular oncogenic pathway, in cancer prognosis, and in patients' responsiveness to neo-adjuvant and adjuvant therapies. In addition to these valuable features, miRNAs have been proposed as innovative therapeutics per se and as plausible biological targets in new treatment strategies.