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目的 观察DNA甲基化和组蛋白乙酰化对人结肠癌细胞系癌相关基因的表达和细胞周期的影响。方法 培养 2种结肠癌细胞系SW 1 1 1 6和Colo 32 0 ,分别以去甲基化制剂 5 氮脱氧胞苷 (5 aza 2′ deoxycytidine ,5 aza dC)和 (或 )组蛋白脱乙酰化酶 (histonedeacetylase ,HDAC)抑制剂trichostatinA(TSA)及丁酸盐干预细胞。提取细胞总RNA ,以RT PCR和定量RT PCR法研究抑癌基因p1 6 INK4A、APC、p2 1 WAF1 、p5 3和 p73以及癌基因c myc和c Ki ras、凋亡抑制基因survivinmRNA表达水平 ;并运用流式细胞术检测细胞周期变化。结果 正常情况下 ,SW 1 1 1 6和Colo 32 0细胞系中均有较弱的 p1 6 INK4A和APC表达 ;两种结肠癌细胞系 p2 1 WAF1 表达缺如 ,而 p5 3、p73和c myc、c Ki ras以及survivin均表达。以 5 aza dC干预后 ,p1 6 INK4A和APC表达增强 ,且不同的结肠癌细胞系表达增强最明显时 5 aza dC干预的时间与浓度不同。相反 p2 1 WAF1 仍无明显表达。值得注意的是这两个细胞系经TSA或丁酸盐处理后 ,p2 1 WAF1 转录水平显著上调。p5 3、p73、c myc、c Ki ras和survivin基因在干预前后表达无明显变化。另外 ,5 aza dC并不能改变细胞周期 ,而TSA或丁酸盐使细胞阻滞于G1 期。结论 两种人结肠癌细胞系中 ,p1 6
Objective To investigate the effects of DNA methylation and histone acetylation on the expression of cancer-related genes and cell cycle in human colon cancer cell lines. Methods Two colon cancer cell lines, SW 1 1 1 6 and Colo 32 0, were cultured and deacetylated with 5 aza 2 deoxycytidine (5 aza dC) and / or histone deacetylated Histone deacetylase (HDAC) inhibitor trichostatin A (TSA) and butyrate interfere with cells. The total cellular RNA was extracted and the expression of survivin mRNA of tumor suppressor gene p1 6 INK4A, APC, p2 1 WAF1, p5 3 and p73 as well as oncogene c myc and c Ki ras were detected by RT-PCR and quantitative RT-PCR. Cell cycle changes were detected by flow cytometry. Results Under normal conditions, weaker expression of p1 6 INK4A and APC were observed in both SW1 1 1 6 and Colo 32 0 cell lines; p2 1 WAF1 expression was absent in both colon cancer cell lines, whereas p5 3, p73 and c myc , C Ki ras and survivin were expressed. The expression of p16 INK4A and APC was enhanced after 5-aza dC intervention, and the time and concentration of 5-aza dC intervention were different when the expression of p-6 INK4A and APC was enhanced in different colon cancer cell lines. On the contrary p2 1 WAF1 still no significant expression. It is noteworthy that p2 & lt; 1 & gt; WAF1 transcriptional levels were significantly up-regulated after TSA or butyrate treatment in both cell lines. p53, p73, c myc, c Ki ras and survivin gene expression before and after intervention no significant change. In addition, 5-aza dC did not alter the cell cycle, whereas TSA or butyrate blocked cells in the G1 phase. Conclusions Two human colon cancer cell lines, p1 6