Effect of miR-5787 on breast cancer cell invasion and proliferation by targeting HSPG2 gene / 中国医师杂志

ABSTRACT

Objective:To observe the expression of microRNA (miRNA, miR)-5787 in breast cancer tissues and various cell lines, analyze the effect of overexpression of miR-5787 on breast cancer cell invasion and proliferation, and explore its possible molecular mechanism.Methods:Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) method was used to detect the expression of miR-5787 in 47 breast cancer tissues and adjacent tissues, 4 breast cancer cell lines and normal breast epithelial cells. Breast cancer cell lines with the lowest miR-5787 expression were selected and transfected with miR-5787 mimics (experimental group) and control NC mimics (control group), respectively. qRT-PCR was used to detect the expression of miR-5787 in cells of the two groups. Transwell invasion experiment and cell counting kit-8 (CCK-8) were used to detect the effect of miR-5787 overexpression on breast cancer cell invasion and proliferation. Bioinformatics software and dual luciferase reporter gene experiments were used to predict and verify the target genes that miR-5787 could complementally bind. qRT-PCR and Western blot were used to detect the expression of target gene mRNA and protein.Results:Compared with adjacent tissues (5.05±0.82), the expression of miR-5787 in breast cancer tissues (1.32±0.33) was significantly reduced ( P<0.01). Compared with normal breast epithelial cells, the expression of miR-5787 in the four breast cancer cell lines was reduced ( P<0.05), and the expression in HCC1937 cells was the lowest ( P<0.01). After transfection of miR-5787 mimics, the expression of miR-5787 in HCC1937 cells in the experimental group was significantly higher than that in the control group ( P<0.01). Overexpression of miR-5787 could inhibit the invasion ( P<0.05) and proliferation ( P<0.05) of breast cancer HCC1937 cells. Bioinformatics software showed that the target gene of miR-5787 might be heparan sulfate proteoglycan 2 (HSPG2), and miR-5787 could complement HSPG2 mRNA ( P<0.01). qRT-PCR and Western blot indicated that overexpression of miR-5787 could significantly inhibit the expression of HSPG2 gene ( P<0.01), with the decreased expression of Vimentin, N-cadherin, Ki67 and PCNA. Conclusions:miR-5787 expression was low in breast cancer tissues and cell lines. Overexpression of miR-5787 could inhibit the invasion and proliferation of breast cancer HCC1937 cells by interfering with the expression of HSPG2 gene.