摘要
目的:探讨5-氮杂-2’-脱氧胞苷(5-Aza-2’-deoxycytidine,5-Aza-CdR)对SW480细胞生物学行为及15-羟基前列腺素脱氢酶(15-hydroxyprostaglandin dehydrogenase,PGDH)蛋白表达的影响。方法:5-Aza-CdR处理SW480细胞,通过MTT法、平板克隆实验观察细胞生长活性的变化,甲基化特异性PCR检测PGDH启动子区的甲基化状态,Western印迹法检测PGDH蛋白表达改变,并进行细胞周期分析。结果:SW480细胞经5-Aza-CdR处理后,与未处理对照组相比,生长速度出现不同程度减慢;实验组细胞(不同浓度5和10μmol/L)较对照组细胞的克隆形成率明显降低,差异有统计学意义(P<0.01);PGDH启动子区甲基化程度降低,无PGDH蛋白表达的SW480细胞检测到蛋白重新表达。5-Aza-CdR处理SW480细胞后,能够延缓细胞周期G1/S期进程,阻滞细胞于G1期。结论:在结肠癌细胞系中,PGDH基因启动子CpG岛的异常甲基化修饰可能导致其表达缺失,5-Aza-CdR能够恢复PGDH基因的表达,为结肠癌的去甲基化治疗提供理论依据。
Objective： To explore the effect of 5-Aza-2＇ -deoxycytidine （5-Aza-CdR） on the molecular biological behaviors of SW480 cells and the expression of 15-hydroxyprostaglandin dehydrogenase （PGDH）. Methods： Colorectal carcinoma SW480 cells were treated with 5-Aza-CdR. Cell proliferation was determined by MTT assay and plate colony formation test. The methylation status of the tumor suppressor gene PGDH was detected by methylation-specific PCR. The expression of PGDH protein was measured by Western blotting and the cell cycle was analyzed by flow cytometry. Results： It was shown that 5-Aza-CdR decreased the proliferation rate of SW480 cells compared with control group. The clony formation rate of SW480 cells decreased significantly after treatment with 5-Aza- CdR in 5 and 10μmol/L compared with the control group （35.4% and 26.5% vs 59.35% , P 〈0.01 ）. The methylation degree in the promoter of PGDH gene was decreased and the expression of PGDH protein was detected after 5-Aza-CdR treatment. 5-Aza-CdR treat- ment induced G1 phase arrest of the SW480 cells. Conclusion：The hypermethylation of CpG islands in the promoter of PGDH gene re- suits in the loss of PGDH protein expression in human colorectal carcinoma cell line. The demethylating agent 5-Aza-CdR could restore PGDH gene expression. These findings provide theoretic evidence for clinical treatment of human colorectal carcinoma with demethylation agent 5-Aza-CdR.
出处
《肿瘤》
CAS
CSCD
北大核心
2008年第8期656-659,共4页
Tumor
基金
山西省科学技术发展计划项目(编号:2006031087-02)
