Dysregulation of miRNAs as a signature for diagnosis and prognosis of gastric cancer and their involvement in the mechanism underlying gastric carcinogenesis and progression

Gastric cancer (GC) is the second main cause of cancer-related mortality worldwide. The poor prognosis and survival of GC are due to diagnosis in an advanced, noncurable stage and with a restricted response to chemotherapy. GC is usually monitored in an advanced stage; therefore, the poor prognosis and lower level of survival rate with a restricted response to chemotherapy can be detected. Valuable and sensible biomarkers are urgently needed to display screen patients with a high risk of GC that can complement endoscopic diagnosis. Such biomarkers will enable the efficient prediction of the therapeutic response and prognosis of GC patients and prefer the establishment of an advantageous treatment method for each and every patient. Noninvasive diagnostic biomarkers may additionally make a contribution to the early identification of GC and enhance medical management. MicroRNAs (miRNAs) are a group of small noncoding RNAs that have displayed a strong association with GC. Accumulating evidence indicates that miRNAs are potential biomarkers with more than one diagnostic function for GC. Actually, miRNAs regulate cell proliferation, apoptosis, migration, invasion, and metastasis via many biological pathways through the repression of target mRNAs. The current review is accordingly to spotlight the multifaceted roles of miRNAs in GC, which would provide indications for future research. Therefore, we review right here the aberrant expression of miRNAs and underlying mechanisms, consequent effects due to miRNAs dysregulation, and accountable target genes in GC. Besides, potential clinical applications are also highlighted.