摘要
目的观察甲基化抑制剂5一氮杂胞苷(5-azaC)对甲状腺乳头状癌细胞TPC一1生长的抑制作用及对抑癌基因Dickkopf同源序列3(DDK3)的转录调节作用。方法经2、5、10、20、50、100、200、400ixmol/L的5-azaC处理TPC一1细胞后,采用噻唑蓝(MTT)观察药物对细胞的生长抑制作用;以逆转录一聚合酶链反应(RT—PCR)、甲基化特异性PCR(MSP)检测细胞经5、10、20、50μmol/L的5-azaC处理后DKK3基因mRNA的表达及DKK3基因甲基化状态。结果经不同浓度5-azaC处理TPC一1细胞后,MTF检测到细胞的生长受到抑制,且呈时间和剂量依赖性(P〈0.05);经5、10、20、50μmol/L的5-azaC处理48h后,DKK3mRNA相对表达量分别为0.208±0.017、0.365±0.013、0.489±0.017、0.582±0.011,表达强度与5-azaC浓度呈剂量依赖关系(F=370.356,P〈0.01);MSP检测结果显示,经5-azaC处理后,DKK3基冈启动子高甲基化的区域发生去甲基化.、结论5-azaC能有效逆转TPC—l甲状腺乳头状癌细胞DKK3基因的异常甲基化,从而激活DKK3基因表达,抑制肿瘤细胞生长。
Objective To study the effects of 5-azacytidine (5-azaC), a methylation inhibitor, on the growth of thyroid papillary cancer-1 ( TPC-1 ) papillary thyroid carcinoma cells and the transcription regulation of DNA guanine cytosine-phosphoric acid-motif (CpG) island demethylation on dickkopf homolog 3 ( DKK3 ) tumor suppressor gene. Methods Methyl thiazol tetrazolium (MTF) method was used to detect the growth of TPC-1 cells after treated with 5-azaC (2, 5, 10, 20, 50, 100, 200 and 400 ~mol/L). The expression of DKK3 mRNA and methylation status were examined by using methylation-specific polymerase chain reaction (MSP) and reverse transcription-polymerase chain reaction (RT-PCR) after TPC-1 cells treated with 5-azaC (5, 10, 20 and 50 I^mol/L). Results 5-azaC reduced viability of TPC-1 ceils in a dose- and time-dependent manner (P 〈 0. 05). After TPC-1 cells were treated with 5-azaC (5, 10, 20 and 50 μmol/L) for 48 h, the relative expression of DKK3 mRNA was 0. 208 ±0. 017, 0. 365± 0. 013, 0. 489±0. 017 and 0. 582±0. 011 respectively, which was gradually increased in a dose-dependent manner ( F = 370. 356, P 〈 0.05 ). Meanwhile, DKK3 gene was demethylated partly in TPC-1 cells treated with 5-azaC. Conclusion 5-azaC might effectively cause the demethylation of DKK3 gene CpG-rich promoter regions, which may activate the expression of DKK3 gene and inhibit the growth of TPC-1 cells.
出处
《中华实验外科杂志》
CAS
CSCD
北大核心
2013年第3期484-486,共3页
Chinese Journal of Experimental Surgery
基金
河南省医学科技攻关计划省部共建项目,郑州大学第一附属医院青年创新基金项目