Expression of miR-769-3p in bladder cancer tissues and the effect of its down-regulation on the migration and cell cycle of bladder cancer J82 cells / 国际外科学杂志

ABSTRACT

Objective:To explore the expression level of miR-769-3p in bladder cancer tissues, and observe the effect of silencing miR-769-3p on the migration ability and cell cycle of J82 cells by down-regulating the expression level of miR-769-3p in bladder cancer J82 cells.Methods:The OncomiR database was used to analyze the expression differences of miR-769-3p in bladder cancer tissues and adjacent tissues. J82 cells were transfected with Lipofectamine 2000 transfection reagent and divided into si-miR-769-3p group (transfected with miR-769-3p small molecule interference fragments) and control group (transfected with meaningless sequences). quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the relative expression level of miR-769-3p after transfection. The cell scratch test and flow cytometry were used to compare the migration ability and cell cycle differences between the two groups of J82 cells. The bioinformatics software MicroRNAdb was used to predict the target gene of miR-769-3p. The dual-luciferase reporter gene assay was used to verify the complementary binding of miR-769-3p to the target gene. qRT-PCR and Western blotting were used to detect the expression levels of miR-769-3p target gene. Measurement data were expressed as mean ± standard deviation ( ± s), and t-test was used for comparison between two groups. Results:The expression of miR-769-3p was significantly increased in bladder cancer tissues compared with adjacent tissues, the difference was statistically significant ( P<0.01). The relative expression of miR-769-3p in the si-miR-769-3p group (1.02 ± 0.16) was significantly lower than that of the control group (4.50 ± 0.60), the difference was statistically significant ( P<0.01). The cell migration rate of the si-miR-769-3p group [(26.67±3.98)%] was significantly lower than that of the control group [(61.86±4.70)%], the difference was statistically significant ( P<0.01). The proportion of cells in the G 0-G 1 phase in the si-miR-769-3p group [(57.66±5.74)%] was significantly higher than that in the control group [(31.26±3.24)%], the difference was statistically significant ( P<0.01). Dual-luciferase reporter gene assay confirmed that endothelin 3 ( EDN3) was the target gene of miR-769-3p. The relative expression of EDN3 mRNA in J82 cells in control group and si-miR-769-3p group was 1.99 ± 0.66 and 6.98 ± 0.76, compared with the control group, the EDN3 mRNA relative expression level of the si-miR-769-3p group was significantly higher than that of the control group, the difference was statistically significant ( P<0.01). Conclusion:Low expression of miR-769-3p can inhibit the migration of bladder cancer J82 cells and block the J82 cell cycle by promoting the expression of EDN3 gene.