三氧化二砷对人宫颈癌Hela细胞的放射增敏作用

Irradiation Enhancement of Arsenic Trioxide on Human Cell Line of Cervical Cancer

目的:探讨三氧化二砷(As2O3)对人宫颈癌Hela细胞的放射增敏作用及其机制。方法:MTT法确定As2O3对Hela细胞的半数致死浓度(ID50);克隆形成法观察20%ID50的As2O3对Hela细胞的放射增敏作用;流式细胞仪测定细胞周期。结果:细胞生长抑制率随As2O3浓度增加而增高;As2O3+照射组的细胞存活率、D0值和Dq值均小于单纯照射组(P<0.05);存活曲线肩区(Dq)变小,放射增敏比(SER)为1.39;As2O3和γ-射线均能使细胞阻滞在G2/M期,联合应用比单独应用抑制作用显著(P<0.01)。结论:As2O3对宫颈癌Hela细胞株有明显的放射增敏作用;可能与As2O3改变细胞周期有关。

Objective To investigate the irradiation enhancement effect of arsenic trioxide on human cervical carcinoma Hela cells and its possible mechanism. Methods MTT assay was used to measure the survival rate of the cervical carcinoma Hela cells. Then the half inhibitory dosage （ ID50 ） was calculated. Colony forming assay was carried out to take count of survival fraction. Cell survival curve was analyzed with Multi - target single - hit model and then sensitive enhancement ratio（SER） was calculated. Flow cytometry was performed to assess the influence of arsenic trioxide on cell cycle distribution. Results （ 1 ） Inhibitory effect of arsenic trioxide on cell proliferation was in a dose - dependent manner. （ 2 ） Cell survival rate was lower after treatment with the combination of arsenic trioxide and radiation than that of radiation alone ,Dq and D0 value were decreased after treatment with the combination of arsenic trioxide and radiation than that of radiation alone（ Dq：1.03 Gy vs 1.89 Gy, D0 ：2.49 Gy vs 3.45 Gy）, with SER being 1.39. （3）Both Gy^60 Co-γ and 2μmol/L arsenic trioxide could arrest Hela cell to G2/M as assayed by flow cytometry. The inhibitory effect was much more obvious when arsenic trioxide and irradiation were combined than either of them was used alone. Conclusion Arsenic trioxide is able to enhance radiation effect obviously on human cervical squamous carcinoma Hela cells,which may be due to its regulation on cell cycle.