Tumor Suppression or Oncogenic Role of miR-100 in Cancer; Implications for Esophageal Cancer

Esophageal cancer (EC) is one of the deadliest malignancies worldwide. Esophageal squamous cell carcinoma (ESCC) constitutes the most common type of EC in Asian countries. Despite advanced surgical techniques, 5-year survival of the affected patients is very low. Therefore, identification of genetic factors and cellular regulatory pathways, including microRNAs (miRNAs), in esophageal carcinogenesis is necessary for early detection. MiRNAs are a class of small non-coding RNA about 18-24 nucleotides in length that negatively regulate gene expression. Deregulation of miRNAs was shown to have a crucial role in the pathways underlying tumorigenesis and tumor progression. Evidence indicates that aberrant expression pattern of miR-100 is associated with pathogenesis of ESCC. The function and expression pattern of miR-100 in ESCC are controversial and its effects in tumor progression has not been fully elucidated. A better understanding of molecular procedures mediated by miR-100 in carcinogenesis, may lead to the opportunity of exploring potential miR-100 based therapeutic applications. In this review, we provide an overview of miR-100, including its important regulation pathways and target genes involved in the development of cancers, emphasizing on its potential role in ESCC.