摘要
目的:研究组蛋白乙酰化修饰对瘦素诱导的乳腺癌MDA-MB-231细胞生长的影响。方法:采用实时定量PCR、Western blot法测定瘦素和组蛋白去乙酰化酶(histone deacetylase,HDAC)抑制剂SAHA对乳腺癌MDA-MB-231细胞生长的影响。应用染色质免疫沉淀(chromatin immunoprecipitation,Ch IP)技术了解瘦素和SAHA影响组蛋白乙酰化水平的程度。结果:瘦素与乳腺癌MDA-MB-231细胞作用后HDAC1的mRNA和蛋白表达明显增强,并伴有组蛋白H3、H4乙酰化水平降低(P<0.05)。ChIP结果显示瘦素处理的乳腺癌细胞p21^(WAF/CIP1)启动子区域与乙酰化组蛋白H3、H4结合的染色质物质明显少于未处理细胞组的相同区域(P<0.05)。结论:瘦素诱导乳腺癌细胞增殖过程中伴随组蛋白乙酰化水平的变化,通过激活HDAC的活性使核心组蛋白去乙酰化,从而抑制p21^(WAF/CIP1)的表达,最终促进细胞周期从G1→S期的进程。
Objective: To study the role of histone aeetylation on Leptin-indueed proliferation of breast cancer MDA-MB-231 cells. Methods: Quantitative real-time PCR and Western blot were used to measure the effects of Leptin and SAHA (a histone deaeetylase inhibitor) on proliferation of breast cancer MDA-MB-231 cells. Chromatin immunopreeipitation (CHIP) was used to detect the levels of histone aeetylation after Leptin and SAHA treatment. Results: Leptin significantly enhanced the HDAC1 activity in MDA-MB-231 cells, accompanied with lower levels of histone H3 and H4 acetylation (P 〈 0.05) . ChIP analysis showed that activated HDAC1 reduced the load of aeetylated histones (H3 and H4) to the p21^WAF/CIP1 promoter, which significantly decreased the expression levels of p21^WAF/CIP1 mRNA and protein (P 〈 0.05), and accelerated the cell cycle progression. Conclusion: Leptin's effects on MDA-MB-231 cells are associated with HDAC1 activation, which decrease H3/H4 aeetylation status and restrains the effects of p21^WAF/CIP1 on cell cycle, thereby contributing to triple-negative breast carcinogenesis.
出处
《沈阳医学院学报》
2017年第1期11-14,共4页
Journal of Shenyang Medical College
基金
国家自然科学基金项目(No.81172509)