摘要
目的 探讨抗组蛋白乙酰化酶抑制剂丁酸钠 (sodiumbutyrate ,NaBu)的作用机制 ,了解肿瘤条件液诱导的启动子PⅡ、PⅠ 3异常激活的分子机制。方法 获取原代脂肪成纤维细胞 ,加入MCF 7的条件培养液 ,作为启动子(PⅡ ,PⅠ 3)激活的细胞模型。用PⅡ ,PⅠ 3启动子报道质粒瞬时转染、染色体免疫沉淀法等方法观察NaBu对PⅡ ,PⅠ 3活性的影响。结果 肿瘤条件液诱导PⅡ /PⅠ 3的活性 ,反应序列位于 - 14 0 /- 5 17bp间。NaBu处理抑制PⅡ /PⅠ 3活性 ,反应序列位于 - 14 0 /- 5 17bp间。C/EBPβ及激活态的ATF 2的结合与PⅡ、PⅠ 3启动子活性呈正相关 ,其结合被NaBu抑制。结论 PⅡ、PI 3激活的关键分子机制在于C/EBPβ、磷酸化ATF 2是否结合于启动子区域。
Objective To understand the action of sodium butyrate (NaBu) on promoter Ⅱ and Ⅰ.3 activity, which can be directed to elucidation of local estrogen production in breast cancer. Methods Primary human adipose fibroblasts (HAF) treated with MCF 7 breast cancer cell conditioned medium were used as a cell model system. Promoter Ⅱ and Ⅰ.3 deletion luciferase constructs were transfected into HAF. Chromatin immunoprecipitation assay was done to evaluate the effects of NaBu on binding pattern of certain transcription factors to promoter region. Results Tumor conditioned medium could induce robustly promoter Ⅱ and Ⅰ.3 activity via a -140/-517 bp region, which could be abolished by NaBu through the same region. Obviously, active bindings of crucial positive transcriptional factors of C/EBPβ or phosphorylated activator trancription factor 2 (ATF 2) were responsible for the activation of promoters, which could be disrupted in the presence of NaBu. Conclusion The activation of promoter Ⅱ and Ⅰ.3 are mediated by active bindings of C/EBPb or/and ATF 2 to promoter region
出处
《华中科技大学学报（医学版）》
CAS
CSCD
北大核心
2004年第2期154-157,共4页
Acta Medicinae Universitatis Scientiae et Technologiae Huazhong
