Effect of lncRNA CRNDE targeting miR-384 on radiosensitivity of colorectal cancer cells / 中华放射医学与防护杂志

ABSTRACT

Objective To study the effect of LncRNA CRNDE on radiosensitivity of colorectal cells and underlying mechanism.Methods Colorectal cancer HT-29 cells were transfected with CRNDE shRNA and the interference efficiency was determined by Real time PCR.HT-29 cells transfected with CRNDE shRNA or co-transfected with CRNDE shRNA and miR-384 inhibitor were irradiated at 8 Gy dose,then cell proliferation and apoptosis were detected by MTT and flow cytometry assay,respectively,and cell radiosensitivity was evaluated by cloning assay.It was predicted by a bioinformatics software that CRNDE and miR-384 have complementary binding sites,and this was identified by a luciferase reporting system.Results CRNDE shRNA reduced the expression of CRNDE in HT-29 cells (1.00±0.08 vs.0.42±0.06,t=10.051,P＜0.05).Both CRNDE shRNA and radiation inhibited the proliferation and induced apoptosis of HT-29 cells,and their combination treatment had synergistic effect in apoptosis induction [Apoptosis rates(2.27±0.13)％,(23.58±2.35)％,(26.91±2.81)％,(36.84±3.24)％,F=24.660,P＜0.05;A values0.45±0.06,0.30±0.02,0.28±0.03,0.20±0.02,F=106.207,P＜0.05].Transfection of CRNDE shRNA increased the radiosensitivity of HT-29 cells with a radiosensitization ratio of 1.374.CRNDE negatively regulated the expression of its target miR-384.The mniR-384 inhibitor antagonized the effect of CRNDE shRNA on proliferation inhibition and apoptosis promotion of radiationtreated colorectal cancer cells.Conclusions Down-regulation of LncRNA expression enhances the radiosensitivity of colorectal cancer cells by regulating miR-384 expression.