Regulatory effects and mechanism of miR-381-3p on proliferation,invasion,and migration of oral cancer cells
Objective To observe the regulatory effects of miR-381-3p on the proliferation,invasion,and migration abilities of oral cancer cells,and to explore the relevant mechanism based on methyltransferases SETDB1 gene regulation.Methods The miR-381-3p in the oral cancer cell line CAL-27 and the normal oral mucosal epithelial cell line ATCC was detected by RT-PCR.CAL-27 cells were cultured and divided into the mimic,negative control and untransfected groups,and cells in the mimic and negative control groups were transfected with miR-381-3p mimic and miR-381-3p negative con-trol,respectively,and cells in the untransfected group were not transfected.cell proliferation ability was measured by CCK-8 assay,Transwell chamber assay was used to measure the cell invasion,and cell migration ability was determined by Scratch-healing assay.TargetScan(http://www.targetscan.org/vert_80/)was used to predict the binding sites be-tween miR-381-3p and SETDB1,and we tested this with the dual luciferase report gene analysis.The SETDB1 mRNA was detected by RT-PCR in CAL-27 cells and ATCC cells and SETDB1 protein was detected by Western blotting.CAL-27 cells were divided into the mimic group,negative control group and untransfected group,cells in the mimic and negative control groups were transfected with miR-381-3p mimic and miR-381-3p negative control,and cells in the untransfected group were not transfected.SETDB1 mRNA in each group was detected by RT-PCR.Results The expression of miR-381-3p was lower in CAL-27 cells than in ATCC cells(P<0.05).The cell proliferation abilities of miR-381-3p in the mim-ic group were lower than those of the miR-381-3p negative control group and untransfected group at 12,24,36 and 48 h(all P<0.05).The number of transmembrane cells and cell migration distance in miR-381-3p mimic group were lower than those in the miR-381-3p negative control group and untransfected group(all P<0.05).SETB1 gene had a continuous nucleotide sequence that could complement miR-381-3p.Relative luciferase activity of CAL-27 cells co-transfected with SETDB1-WT and miR-381-3p was lower than that of cells in the other groups(all P<0.05).The expression levels of SET-DB1 mRNA and protein in the CAL-27 cells were higher than those in the ATCC cells(both P<0.05);the expression of SETDB1 mRNA was lower in the mimic group than in the negative control group and the untransfected group(all P<0.05).Conclusion MiR-381-3p can inhibit the proliferation,invasion and migration of oral cancer cells,and its mechanism may be related to regulation of SETDB1 expression.