Down-regulation of lncRNA SNHG6 inhibits breast cancer progression by targeting miR-30-5p/FKBP3 axis / 中华内分泌外科杂志

ABSTRACT

Objective:To investigate the relationship between lncRNA SNHG6 and breast cancer and its possible mechanism.Methods:Fluorescence quantitative PCR was used to detect the expression of SNHG6, miR-30-5p, and FKBP3 in human normal breast epithelial cell line MCF-10A and human breast cancer cell line MCF-7. According to the experiment content, MCF-7 cells were divided into the following groups:① si-NC group, si-SNHG6 group, si-NC+miR-30-5p inhibitor group and si-SNHG6+miR-30-5p inhibitor group;②miR-NC group, miR-30-5p inhibitor group, miR-30-5p inhibitor+sh-NC group and miR-30-5p inhibitor+sh-FKBP3 group. The expression of SNHG6 was inhibited by siRNA technology, and the miR-30-5p mimic (mimic) , inhibitor (inhibitor) and negative control (miR-NC) were transfected into MCF-7 cells by liposome-mediated method. A short hairpin RNA (shRNA) lentiviral expression vector targeting FKBP3 gene was constructed to inhibit FKBP3 expression. CCK-8, cell colony formation experiment, cell wound healing experiment and Transwell experiment were used to observe the proliferation, migration and invasion of MCF-7 cells in each group. Bioinformatics software, dual luciferase reporter gene experiment and Western blotting were used to analyze the targeting relationship between SNHG6 and miR-30-5p, miR-30-5p and FKBP3.Results:Compared with MCF-10A cells, the expression levels of SNHG6 and FKBP3 in MCF-7 cells increased significantly, while the expression levels of miR-30-5p decreased significantly ( t=21.097, P=0.000; t=17.812, P=0.000; t=33.671, P=0.000) . Compared with si-NC group, the proliferation activity of MCF-7 cells in the si-SNHG6 group was significantly inhibited ( t=19.569, P=0.000; t=25.077, P=0.000) , and the number of cell colonies formed significantly decreased ( t=34.071, P=0.000) . Migration and invasion of cells were also inhibited ( t=33.419, P=0.000; t=29.372, P=0.000) . There were complementary binding sites between miR-30-5p and SNHG6. The luciferase activity of miR-30-5p mimic and SNHG6-WT co-transfected group was significantly lower than that of miR-NC and SNHG6-WT co-transfected group ( t=31.596, P=0.000) . The proliferation, migration and invasion of MCF-7 cells in each group were significantly different ( F=268.014, F=398.483, F=244.962) . Compared with si-SNHG6 group, the proliferation, migration and invasion ability of MCF-7 cell in si-SNHG6+miR-30-5p inhibitor group increased significantly ( P=0.000) ; Compared with si-NC+miR-30-5p inhibitor group, the proliferation, migration and invasion ability of MCF-7 cells in si-SNHG6+miR-30-5p inhibitor group decreased significantly ( P=0.000) . There were complementary binding sites between miR-30-5p and 3’UTR of FKBP3. The luciferase activity of miR-30-5p mimic and FKBP3-WT co-transfected group was significantly lower than that of miR-NC and FKBP3-WT co-transfected group ( t=28.557, P=0.000) . After transfection, the FKBP3 protein expression of MCF-7 cells in each group was significantly different ( F=102.523) . Compared with miR-NC group, FKBP3 protein expression of miR-30-5p mimic group was significantly reduced, while FKBP3 protein expression of miR-30-5p inhibitor group was significantly increased ( P=0.000) . The proliferation, migration and invasion of MCF-7 cells in each group were significantly different ( F=177.036, F=285.530, F=217.992) . Compared with miR-30-5p inhibitor group and miR-30-5p inhibitor+sh-NC group, the proliferation, migration and invasion ability of MCF-7 cells in miR-30-5p inhibitor+sh-FKBP3 group was significantly decreased ( P=0.000 ) . Conclusion:Inhibiting the expression of miR-30-5p can reverse the inhibitory effect of down-regulation of SNHG6 on the proliferation, migration and invasion of MCF-7 cells.