Abstract: Objective To investigate the expression and the expression change of miR-551b-3p in gastric cancer and its effect on the function of gastric cancer cells. Methods miR-551b-3p was detected by RT-PCR in 60 cases of gastric cancer samples and their paired adjacent normal control tissues. HGC-27 cell line was infected by miR-551b-3p mimic, then CCK-8 assay was used to determine the influence of miR-551b-3p on HGC-27 cell proliferation; Wound-healing assay was used to determine cell migration; Transwell assay was used to determine cell invasion. Results 1) The expression of miR-551b-3p in gastric tumor tissues was significantly lower than that of the adjacent tissues (P<0.05). 2) HGC-27 cell proliferation, migration and invasion were significantly decreased while the cell infected by mimic-miR-551b-3p. Conclusions miR-551b-3p expresses lower in gastric cancer tissues and is able to inhibit gastric cancer line HGC-27 proliferation, migration and invasion. miR-551b-3p is closely associated with the development of gastric cancer.

Key words: miR-551b-3p, gastric cancer, proliferation, migration and invasion