ABSTRACT
@#Objective: To detect the expression of miR-133a-3p in gastric cancer (GC) tissues and plasma of GC patients, and to investigate its effect on the proliferation of GC cells as well as its correlation toprognosis of GC patients. Methods: 52 cases of cancertissues (non-necrosis part) and corresponding adjacent tissues as well as the pre-operative peripheral blood samples from GC patients, who underwent surgery at Department of General Surgery, the Forth Hospital of Hebei Medical University(Shijiazhuang, China) between May 2012 and May 2013, were collected for this study. The plasma sample (n=35) from healthy donors were obtained during their physical examination. RT-qPCR was adopted to detect the expression of miR-133a-3p in gastric cancer tissues, adjacent tissuesand plasma samples of GC patients and healthy volunteers. The relationships between miR-133a-3p expression and the median DFS as well as clinicopathological parameters were also analyzed. CCK-8 assay was adopted to detect the effect of miR-133a-3p silence or over-expression on proliferation of gastric cancer SGC7901 cells. Results: miR-133a-3p was dramatically decreased in gastric cancer tissues (P<0.01), and its expression was associated with TNM stage, tumor infiltration (T), lynphonode metastasis (N), and vascular tumor thrombus (all P<0.01); miR-133a-3p was significantly increased in the plasma of GC patients (P<0.01), and its expression was associated with TNM stage, lynphonode metastasis (N), and vascular tumor thrombus (all P<0.05). miR-133a-3p expression was positively correlated with serum CA199 level of GC patients (P<0.01). The median DFS of patients with high miR-133a-3pexpression in cancer tissues was significantly longer than that of the patients with low expression(20.8 vs 14.8 months, P<0.05); The median DFS of patients with high plasma miR-133a-3p expression was significantly shorter than that of the patients with low expression (14.4 vs 20.3 months, P<0.05). Over-expression of miR-133a-3p could significantly inhibit the proliferation of gastric cancer SGC7901 cells, while miR-133a-3p silence could significantly promote the proliferation (all P<0.05). Conclusion: miR-133a-3p could significantlyinhibit the proliferation of SGC7901 cells; miR-133a-3p aberrantlyexpressed in gastric cancer tissues and plasma, and obviously correlated with prognosis of gastric cancer patients, which may be used as a potential clinical bio-maker for early diagnosis and treatment as well as the prognosis prediction of gastric cancer.