The Value of miR-299-5p in Diagnosis and Prognosis of Intestinal-Type Gastric Adenocarcinoma.

MicroRNAs (miRNAs) are a class of non-coding RNAs, containing about 22 nucleotides and having a pivotal function in various cellular processes. The oncogenic and tumor suppressor roles of miRNAs have been identified in cancers especially in gastric cancer, which is one of the most prevalent cancers. MiR-299-5p is located in the imprinted Dlk1-Dio3 region in chromosome 14q32. Aberrant expression of miR-299-5p was determined in solid and blood cancers. The current study was performed to assess the expression pattern of miR-299-5p in intestinal-type gastric adenocarcinoma and compare it with the normal adjacent counterparts. The expression level of miR-299-5p was investigated in forty fresh specimens which were obtained from gastric cancer patients during endoscopy. Moreover, the association of aberrant expression of miR-299-5p and clinicopathological features, as well as the susceptibility of miR-299-5p as a tumor marker, was determined. The result of qRT-PCR revealed the downregulation of miR-299-5p in intestinal-type gastric adenocarcinoma compared with adjacent tumor-free tissues (P < 0.001); this misregulation can be used as a tumor marker. Analysis of miR-299-5p misregulation did not reveal a significant correlation with clinical features. The result obtained from the present study revealed the significant downregulation of miR-299-5p in intestinal-type gastric adenocarcinoma which is consistent with previous studies showing miR-299-5p downregulation in other types of cancers. The data obtained from the current study suggest basic information which can be very helpful for future research in the field of diagnosis and treatment of gastric cancer.