p14^(ARF)对照射后肺癌细胞加速再群体化抑制效应

Suppressing effect of tumor suppression protein p14^(ARF) on accelerated repopulation of irradiated human lung carcinoma cells after irradiation

目的 探讨抑癌蛋白p14ARF功能恢复对照射后肺癌细胞加速再群体化的影响。方法 以ARF基因纯合缺失但表达野生型p5 3的人肺腺癌A5 49和H46 0细胞系为靶细胞 ,应用Fugene 6对照射后的细胞进行pCI neo p14ARF 表达载体基因转染 ,检测照射前后和转染前后细胞潜在倍增时间(Tpot)、细胞周期分布及克隆存活率变化。结果 6GyX射线照射后 96h处 ,A5 49和H46 0细胞Tpot分别缩短 2 5 .4%和 2 9.2 % ,与照射前比较差异有显著性意义 (P <0 .0 1)。此时进行p14ARF表达载体基因转染 ,恢复p14ARF功能 ,可使A5 49和H46 0细胞Tpot延长并接近照射前水平 ,同时伴随G0 G1 期和G2 M期细胞显著增加 ,S期细胞显著下降 ,克隆存活率下降。结论 A5 49和H46 0细胞照射后存在加速再群体化。p14ARF功能恢复对其照射后加速再群体化有抑制作用 ,该作用与p14ARF的G1 、G2

Objective To study the suppressing effect of tumor suppression protein p14 ARF in its functional restoration of accelerated repopulation of irradiated human lung carcinoma cells.Methods Target cells used in this study were homogenous ARF gene lost but wild type p53 expressed in human lung adenocarcinoma cell lines A549 and H460. The cells were transfected with the human p14 ARF expression vector (pCI neo p14 ARF ) by the new nonliposomal transfection reagent Fugene 6. Potential doubling time(T pot ), cell cycle distribution and clone survival rate were monitored before and after irradiation and gene transfection. Results T pot of A549 and H460 cells decreased 25.4%and 29.2% respectively at 96 hours after 6?Gy X ray irradiation. It was significantly shorter than that of the non irradiation group(P<0.01). When the ARF gene was transfected at this time, the T pot of A549 and H460 cells increased significantly and were close to the level of the non irradiated group. The cell proportion of G 0/G 1 and G 2/M phases increased, S phase decreased, and clone survival rate also decreased significantly when the T pot was prolonged after p14 ARF functional restoration. Conclusions Accelerated repopulation was observed in irradiated human lung adenocarcinoma cell line A549 and H460. It could be suppressed after p14 ARF functional restoration. This might closely be correlated with its G 1 and G 2 blocking effects of p14 ARF .