MicroRNA in the Pathogenesis and Prognosis of Esophageal Cancer

Abstract

Esophageal cancer (EC) is a deadly disease. EC usually occurs as either adenocarcinoma (EAC) or squamous cell carcinomas (ESCC). The development of EAC generally follows the metaplasia-dysplasia-carcinoma sequence. Barrett's esophagus (BE) is a metasplastic precursor of EAC. Multiple global miRNA expression profiling and candidate gene studies have been performed in EAC and ESCC that clearly support the important roles of miRNAs in the pathogenesis of EAC and ESCC. A number of consistently dysregulated miRNAs have been identified in EAC and/or ESCC, including upregulation of miR-21, miR-192, miR-194, miR-106-25 polycistron (miR-25, miR-93, and miR-106b), miR-10b, miR-151, and miR-93, and downregulation of miR-375, miR-203, miR-205, miR-145, miR- 27b, miR-100, miR-125b, let-7c, etc. Most of these miRNAs are also dysregulated in other cancer types and their target genes have been extensively studied in different cancers. The prognostic value of miR-21 and miR-375 has been replicated in independent studies. Circulating miRNAs as potential biomarkers for early detection, prognosis, and treatment response have only been scarcely studied in EC. The association of genetic variations in miRNA regulatory pathway with EC risk or outcome is a largely uncharted territory. Future studies should be focused on the role of miRNAs in the prognosis of EC, the identification of circulating miRNAs and miRNA-related genetic variations as biomarkers in EC, and the biological mechanisms underlying the contribution of miRNA dysreguation to EC. A better understanding of roles of miRNA in EC developemnt may provide new avenues for the early detection, diagnosis, prognosis, and therapy of this deadly disease.

Aberrant Expression of miR-20a and miR-203 in Cervical Cancer

“…In the recent study, miR-203 has significantly low expression in cancer tissues compared to non-tumor counterparts (Viticchiè et al, 2011;Takeshita et al, 2012;Gu et al, 2013), while there were up-regulation of miR-203 was observed in pancreatic adenocarcinomas and breast, cancers (Naoki et al, 2010;Madhavan et al, 2012), we think the differential expression of miRNAs may be the result of tissue-specific differences. Just as Baffa et al suggested (Baffa et al, 2009).…”

Plasma miR-122 and miR-192 as potential novel biomarkers for the early detection of distant metastasis of gastric cancer

“…Previous studies found that miR-192 is significantly increased in many types of cancer (39)(40)(41), but decreased in many others (42,43). Studies have also shown that p53-mediated upregulation of miR-192 prevents EMT in hepatocellular carcinoma through repression of the transcription factor ZEB2 (44).…”

Deregulation of miR-93 and miR-143 in human esophageal cancer

“…In case of esophageal cancer, Wu et al (2011) and Kano et al (2010) reported that the expression levels of miR-143 and miR-145 was significantly decreased in many tissues of esophageal tissues in contrast to normal tissues [24,58]. However, Gu et al (2013) found no significant differences between the most examined miRNAs expression profiles including miR-93 and miR-143 in ESCC as well as in esophageal adenocarcinoma (EAC) [59]. In this study, no significant relationship was found between the expression of miR-93 and miR-143 and other clinicopathological features such as age or gender.…”