Effect Of MiR-374b-5p In Xenogenic Human Gastric Cancer In Nude Mice And The Research On Its Target Gene RECK

Objective:By the model of xenograft human gastric cancer in nude mice to explore the functionof miR-374b-5p and its target gene RECK in growth, invasion and metastasis of gastriccancer.Methods:1. Cultured human gastric cancer cell line MGC-803, using BABL/c nude mice toestablish an animal model of human gastric cancer xenografts.2. Randomly divided into three groups: blank control group, negative control group(internal transfecion nonsense sequence, NC-inhibitor) and miR-374b-5p suppressiongroup (internal transfecion miR-374b-5p inhibitor, Hsa-micro-374b-5p inhibitor), tumorgrowth was observed, the pathological feature of tumor was observed by HE staining.3. The expression levels of miR-374b-5p in xenogenic human gastric cancer in nudemice after internal transfecion was determined by qRT-PCR, whether miR-374b-5ptargeting RECK and regulating its expression was determined by luciferase activity assayexperiments, the mRNA trascripition and the proteins of RECK was determined byqRT-PCR and immunohistochemistry staining.Results:1. The growth of implanted tumor in miR-374b-5p suppression group significantlyslowly than the negative control group and blank control group.2. Pathology test indicate the degree of malignancy in miR-374b-5p suppressiongroup was lower than other two groups.3. The expression levels of miR-374b-5p in miR-374b-5p suppression group wassignificantily lower than other two groups.4. miR-374b-5p directly targets RECK was proved by luciferase reporter vectorsystem.5. The mRNA transcription levels and the protein expressions of RECK in miR-374b-5p suppression group was significantily higher than other two groups.Conclusions:1. miR-374b-5p may play a cancer gene role in gastric cancer.2. miR-374b-5p may play a role in growth, invasion and metastasis of gastric cancerthrough the RECK pathway.