bcl-2反义寡核苷酸对小细胞肺癌细胞NCI-H69放射敏感性的影响

EFFECT OF bcl-2 ANTISENSE OLIGODEXYNUCLEOTIDES ON RADIOSENSITIVITY OF THE CELL LINE NCI-H69 OF HUMAN SMALL-CELL LUNG CANCER

目的研究bcl-2反义寡核苷酸对人小细胞肺癌细胞NCI-H69放射敏感性的影响。方法将NCI-H69细胞培养传代,然后将细胞分为反义寡核苷酸组、正义寡核苷酸组、无义寡核苷酸组和空白对照组,通过脂质体将不同寡核苷酸导入细胞中,用Western-Blot法检测Bcl-2蛋白的表达。采用直线加速器分别以不同剂量（0、2、4、6、8、10 Gy）X线照射4组细胞。收集照射后的细胞,流式细胞仪检测细胞凋亡率,MTT法测定细胞存活分数。结果Western-Blot杂交显示反义寡核苷酸组无Bcl-2蛋白表达,相对正义寡核苷酸组、无义寡核苷酸组及空白对照组Bcl-2蛋白表达明显受到抑制（F=7.24-15.31,q=5.03-7.80,P〈0.01）。细胞经X线照射后,反义寡核苷酸组细胞凋亡率明显高于空白对照组,差异具有显著性（F=7.24-15.31,q=5.03-7.80,P〈0.01）;正义寡核苷酸组和无义寡核苷酸组与空白对照组相比无统计学差异。4组细胞接受辐射后,反义寡核苷酸组在未照射和照射不同剂量后的存活分数均低于空白对照组,差异有统计学意义（F=11.04-45.56,q=5.10-14.75,P〈0.01）,而正义寡核苷酸和无义寡核苷酸组与空白对照组比较则无统计学差异。结论bcl-2反义寡核苷酸能有效封闭bcl-2基因的表达,增强小细胞肺癌细胞NCI-H69对X线的敏感性。

Objective To study the effect of bcl-2 antisense oligodexynucleotides on radiosensitivity of the cell line NCIH69 of human small-cell lung cancer. Methods Cultured NCI-H69 cells were divided into antisense oligodexynucleotides （ASODN）, sense oligodexynucleotides （SODN）, nonsense oligodexynucleotides （NSODN） and blank groups. The different Bcl-2 oligodexynucleotides were transfected into corresponding cells using Oligofectamine. Expression of Bcl-2 was examined by Western- Blot. The different group cells were irradiated by different dose of X-ray （0,2,4,6,8, and 10 Gy） via 6MV linearity accelerator, the apoptotic cells were then detected by flow cytometry and cell growth assessed by MTT test. Results The Bcl-2 expression in ASODN group was significantly inhibited compared with other groups （F=7.24-15.31, q= 5.03- 7.80, P〈0.01 ）. The apoptotic rate of ASODN group was significantly higher than that of other groups （F= 11.04- 45.56, q= 5. 10-14.75, P〈0. 01 ）, and the survival fraction of ASODN group was significantly lower than that of the others. Conclusion The bcl-2 ASODN enhances the radiosensitivity of the cell line NCI-H69 of small-cell lung cancer via blocking bcl-2 gene expression.