Silencing long non-coding RNA HCP5 increases the radiosensitivity of glioma cells by up-regulating miR-508-3p expression / 中华行为医学与脑科学杂志

ABSTRACT

Objective:To investigate the effect of long non-coding (lnc) RNA HCP5 on the radiation sensitivity of glioma cells and underlying mechanism.Methods:The glioma cells U251 and U87 were irradiated with 0, 2, 4, 6, and 8 Gy rays as different doses.si-Con, si-HCP5, pcDNA, and pcDNA-HCP5 were transfected into cells U251 and U87, recorded as si-con group, si-HCP5 group, pcDNA group, and pcDNA-HCP5 group.si-Con and si-HCP5 were transfected into cells U251 and U87, and then irradiated with 4 Gy rays, respectively, recorded as IR+ si-con group and IR+ si-HCP5 group, the cells only irradiated with 4 Gy rays were recorded as IR group.After si-HCP5 with anti-miR-con and anti-miR-508-3p was co-transfected into cell U251 and U87, respectively, irradiated with 4 Gy rays, recorded as IR+ si-HCP5+ anti-miR-con group and IR+ si-HCP5+ anti-miR-508-3p group, respectively, the transfection was performed by liposome method.RT-qPCR was used to detect the expression of miR-508-3p and HCP5.Cell clone formation assay was used to detect the radiosensitivity of glioma cells.Flow cytometry was used to detect apoptosis, dual luciferase Reporter gene detection experiments detects fluorescence activity.Results:HCP5 was highly expressed in radiation-treated glioma cells, and miR-508-3p was lowly expressed.After silenced HCP5, U251 and U87 cells had enhanced radiosensitivity and apoptotic rate((16.67±1.68) vs (3.58±0.62), t=21.929, P<0.05; (12.32±1.08) vs (4.48±0.71), t=18.198, P<0.05) was increased, and γ-H2AX( (0.45±0.04) vs (0.23±0.05), t=10.307, P<0.05; (0.38±0.04) vs (0.24±0.03), t=8.400, P<0.05), Cleaved caspase-3((0.37±0.04) vs (0.16±0.03), t=12.600, P<0.05; (0.38±0.04) vs (0.22±0.03), t=9.600, P<0.05) expressions were increased.Compared with silencing HCP5 or radiation treatment alone, silencing HCP5 and radiation treatment of U251 cells simultaneously, the apoptosis rate ((25.34±1.54) vs (16.67±1.68), t=11.413, P<0.05; (25.34±1.54) vs (11.13±1.06), t=22.802, P<0.05) was significantly increased, and γ-H2AX((0.69±0.05) vs (0.45±0.04), t=11.245, P<0.05; (0.69±0.05) vs (0.31±0.04), t=17.804, P<0.05), Cleaved caspase-3 ((0.52±0.06/0.37±0.04, t=6.240, P<0.05) (0.52±0.06/0.34±0.04, t=7.488, P<0.05) expressions were increased.The expressions of p-PI3K ((0.21±0.02) vs (0.52±0.04), t=20.795, P<0.05; (0.26±0.23 ), ( 0.67±0.07), t=5.116, P<0.05), p- AKT ((0.22±0.03) vs (0.66±0.07), t=17.332, P<0.05; (0.23±0.04) vs (0.71±0.03), t=28.800, P<0.05) in U251 and U87 cells were decreased.HCP5 can target the regulation of miR-508-3p expression; interfering with miR-508-3p reversed the effects of silent HCP5 and radiation on the radiation sensitization and apoptosis of U251 and U87 cells.It reduced the expression levels of reducing γ-H2AX and Cleaved caspase-3, while increased the expression levels of p-PI3K and p-AKT. Conclusion:Silencing lncRNA HCP5 can enhance the radiation sensitivity of glioma cells and promote apoptosis.The mechanism may be related with the miR-508-3p and PI3K/Akt signaling pathway, which will provide new targets and new ideas for glioma treatment.