ABSTRACT
Objective:To explore the expression of long non-coding RNA (lncRNA) CDK5RAP3 in gastric cancer tissue and its regulatory effect on gastric cancer cell proliferation and invasion.Methods:The expression differences of CDK5RAP3 in gastric cancer tissues and adjacent tissues were analyzed by TCGA database. By transfecting the pcDNA3.1-CDK5RAP3 plasmid into Hs-746T cells, a gastric cancer cell line overexpressing CDK5RAP3 (CDK5RAP3 group) was constructed, and the pcDNA3.1 plasmid was transfected into Hs-746T cells as a control group. The changes of CDK5RAP3 expression in the two groups of cells were detected by real-time quantitative PCR (qRT-PCR). The effects of overexpression of CDK5RAP3 on the proliferation and invasion of Hs-746T cells were detected by CCK-8 assay and Transwell assay, respectively. The binding sites of CDK5RAP3 and miR-223-3p were predicted by the starBase v2.0 database. The direct binding of CDK5RAP3 and miR-223-3p was verified by dual-luciferase reporter gene experiment. The expression levels of miR-223-3p in Hs-746T cells in each group were detected by qRT-PCR. Western blot was used to detect the expression levels of proliferation proteins and invasion proteins in Hs-746T cells in each group. The experimental data were analyzed by SPSS 17.0 software, and the measurement data conforming to the normal distribution were expressed as Mean±SD. The t-test was used to compare between two groups, and the one-way analysis of variance was used to compare the means of multiple groups. Results:Compared with adjacent tissues, the expression level of CDK5RAP3 in gastric cancer tissues was significantly lower ( P<0.01). The expressions of CDK5RAP3 in Hs-746T cells in the control group and CDK5RAP3 group were (1.08±0.77) and (10.63±2.14), respectively, and the difference was statistically significant ( P<0.01). Up-regulation of CDK5RAP3 significantly decreased the proliferation activity of Hs-746T cells ( P<0.05). The number of invasive cells in the control group and CDK5RAP3 group were (137.80±28.72) and (57.76±24.95), respectively, and the difference was statistically significant ( P<0.01). CDK5RAP3 could directly bind miR-223-3p ( P<0.01). The expression of miR-223-3p in Hs-746T cells in control group and CDK5RAP3 group were (6.22±1.20) and (1.01±0.98), respectively, and the difference was statistically significant ( P<0.01). Compared with the control group, up-regulation of CDK5RAP3 significantly reduced the expression levels of proliferation and invasive proteins. Conclusion:The expression of CDK5RAP3 is low in gastric cancer tissue, and CDK5RAP3 inhibits the proliferation and invasion of gastric cancer Hs-746T cells by targeting miR-223-3p.