Upregulation of microRNA-132 in gastric cancer promotes cell proliferation via retinoblastoma 1 targeting.

Gastric cancer is one of the most frequent malignancies and a leading cause of cancer-related mortality worldwide. MicroRNAs (miRs), a class of small non­coding RNAs, have been shown to be critical in tumorigenesis. In the present study, the expression levels of miR­132 were analyzed in gastric cancer samples using quantitative reverse transcription­polymerase chain reaction. In addition, the cell viability, proliferation and invasion abilities were determined in two gastric cancer cell lines, NCI­N87 and MGC80­3, that were transfected with miR­132 mimics or antisense oligos. It was found that miR­132 expression was significantly upregulated in gastric cancer tissues when compared with adjacent non­cancerous tissues. At the molecular level, the data demonstrated that miR­132 inhibits the protein levels of retinoblastoma 1 (RB1) by targeting the 3'­untranslated region. Furthermore, reintroduction of RB1 markedly attenuated the proliferative roles of miR­132 overexpression. Therefore, the present results indicate that the miR­132/RB1 regulatory axis may be a potential novel diagnostic and therapeutic target for the treatment of gastric cancer.