miR-155对前列腺癌放射治疗的增敏作用

 目的 探讨miR-155在前列腺癌放射治疗(简称放疗)中的增敏作用。方法 转染anti-miR-155,抑制前列腺癌DU145和PC-3细胞中miR-155水平,联合应用放射治1疗,通过观察DU145和PC-3细胞的存活率、黏附率,以及前列腺癌细胞的凋亡率,并观察Caspase-3和Caspase-9表达水平和活性的变化。结果 与对照组相比,DU145和PC-3细胞经放射或anti-miR-155单独处理后,细胞存活率(放射组分别为25.6%±2.0%和21.6±1.0%;anti-miR-155处理组分别为20.5%±1.0%和15.5%±1.0%)和黏附率(放射组分别为0.8%±0.1%和0.7%±0.1%;anti-miR-155处理组分别为0.7%±0.1%和0.6%±0.1%)均显著降低(P<0.01);前列腺癌细胞凋亡率增高(放射组分别为3.3%±0.3%和4.2%±0.3%;anti-miR-155处理组分别为4.1%±0.1%和3.9%±0.2%);Caspase-3和Caspase-9表达水平和活性均提高(P<0.01);联合组的细胞存活率(分别为10.1%±0.5%和6.1%±0.5%)和黏附率(分别为0.4%±0.1%和0.4%±0.1%)低于单独处理组(P<0.01,n=6),细胞凋亡率(分别为6.9%±0.4%和6.8%±0.3%),Caspase-3和Caspase-9表达水平和活性等均高于单独处理组(P<0.01)。结论 抑制miR-155可增加人前列腺癌的放疗敏感性,提高放射线对人前列腺癌细胞的治疗效果,其机制可能与Caspase-3和Caspase-9参与细胞凋亡的途径相关。

Effect of miR-155 on radiosensitivity enhancement of prostate cancer in vitro

Objective To explore the effects of miR-155 on radiosensitivity enhancement of prostate cancer in vitro.Methods Cell viability and adhesion of DU145 and PC-3 cells were evaluated after anti-miR-155 transfection combined with irradiation therapy.Flow cytometry was performed to evaluate the cell apoptosis.The expression and activity of Caspase-3 and Caspase-9 were also observed after the above treatment.Results The results evidenced that cell viability(25.6％ ± 2.0％ and 21.6 ± 1.0％ in irradiated group;20.5％ ± 1.0％ and 15.5％ ± 1.0％ in anti-miR-155 transfected group) and adhesion of DU145 and PC-3 cells(0,g％ ± 0.1％ and 0.7％ ± 0.1％ in irradiated group;0.7％ ± 0.1％ and 0.6％ ± 0.1％ in anti-miR-155 transfected group) were inhibited obviously after anti-miR-155 transfection.The apoptosis rate(3.3％ ±0.3％ and 4.2％ ±0.3％ in irradiated group;4.1％ ±0.1％ and 3.9％ ±0.2％ in anti-miR-155 transfected group),Caspase-3 and Caspase-9 expression and activity were enhanced obviously compared with the control group(P ＜ 0.01).After combinative treatment,cell viability (10.1％ ± 0.5％ in irradiated group and 6.1％ ±0.5％ in anti-miR-155 transfected group) and adhesion (0.4％ ±0.1％ in irradiated group and 0.4％ ±0.1％ in anti-miR-155 transfected group) decreased significantly (P ＜ 0.01,n =6).The apoptosis rate (6.9％ ± 0.4％ in irradiated group;6.8％ ± 0.3 ％ in anti-miR-155 transfected group) and the expression of Caspase-3 and Caspase-9 were also higher than the signal treated group (P ＜ 0.01).Conclusions Our results suggested that miR-155 can increase the radiosensitivity of DU145 and PC-3 cells and increase the efficiency of radiotherapy of γ-ray irradiation on prostate cancer in vitro.