摘要
目的研究甲基化抑制剂5-氮-2′-脱氧胞苷(5-Aza-dc)对T24膀胱癌细胞生长的抑制作用及对RUNX3基因的转录调节作用。方法不同浓度5-Aza-dc处理T24膀胱癌细胞后,采用四唑盐(MTT)比色观察细胞经药物处理前后的生长活性;以半定量反转录-聚合酶链反应(RT-PCR),甲基化特异性PCR(methylationspecific PCR,MSP)检测细胞处理前后RUNX3基因mRNA的表达,RUNX3基因甲基化状态;应用流式细胞仪进行细胞凋亡率的检测。结果5-Aza-dc抑制T24膀胱癌细胞的生长;细胞凋亡增加;RUNX3基因甲基化逆转;mRNA表达恢复。以上作用与药物存在剂量依赖性。结论5-Aza-dc能逆转T24膀胱癌细胞的RUNX3基因甲基化,恢复该基因的表达,诱导T24膀胱癌细胞凋亡。
Objective To study the effects of 5-aza-2＇-deoxycytidine （5Aza-dc）, a methylation inhibitor, on the growth of T24 bladder carcinoma cell lines and the transcription regulation of DNA CpG island demethylation on RUNX3 tumor suppressor gene. Methods MTT method and flow cytometry were used to detect the growth and apop- tosis of T24 after being treated with 5Aza-dc at the various doses. RUNX3 gene DNA, mRNA were determined by MSP and RT-PCR. Results T24 cells treated with 5Aza-dc displayed a slowed growth in comparison with the control cells,5Aza-dc increases T24 cell apoptosis rate. The RUNX3 gene hypermethylation may effectively caused demethylation by 5Aza-dc. The expression of T24 cell RUNX3 mRNA treated with 5Aza-dc recovered. These effects within certain extent are dose dependent. Conclusion 5Aza-dc may effectively cause demethylation and inhibit the growth, induce the apoptosis of T24 by reactivating the gene transcription silenced by aberrant hypermethylation.
