Zhao Ting, Ma Xu-dong, Huang Yi-qun
Department of Hematology, Fujian Medical University, Zhangzhou, China.
Zhonghua Xue Ye Xue Za Zhi. 2013 Jan;34(1):49-54.
To study the effects of suppressor of variegation 3-9 homolog 1 (SUV39H1) gene silencing by small interfering RNA (siRNA) on the proliferation, tumor suppressor gene p15 expression and histone modification in acute myeloid leukemia cell line KG-1 cells, and to explore novel therapeutic target of leukemia.
The SUV39H1 gene specific siRNA was synthesized in vitro and transfected into KG-1 cells by Lipofectamine(TM) 2000. The SUV39H1 mRNA and protein were detected by RT-PCR and Western blot. Cell growth affected by SUV39H1 siRNA was determined by MTS. The expressions of tumor suppressor gene p15, histone methylation of H3K9 and histone acetylation of H3, H3K9, H3K14, H3K27 and H4 were detected by Western blot.
SUV39H1 mRNA was markedly suppressed by the SUV39H1 specific siRNA in a concentration-dependent manner. SUV39H1 siRNA inhibited the proliferation of KG-1 cells. Proliferation inhibition rate was (23.57 ± 1.98)%, (48.69 ± 1.84)%, (62.69 ± 1.61)% and (81.06 ± 3.22)% after transfected with SUV39H1 siRNA at 30, 60, 120 and 240 nmol/L for 48 hours, respectively. SUV39H1 siRNA down-regulated histone tri-methylated-H3K9 by 25%, 33% and 49% compared to control group when treated with SUV39H1 siRNA at 30, 60 and 120 nmol/L for 48 hours, while up-regulated histone acetylated H3K9 by 1.83, 2.16 and 3.07 folds, and global histone H3 in 1.35, 1.87 and 2.37 folds, but no changes were observed in histone acetylation of H3K14, H3K27 and H4. Expression of p15 increased 1.52, 2.89 and 3.08 folds after SUV39H1 siRNA treatment.
SUV39H1 gene silencing could induce the re-expression of p15 and inhibit cell proliferation by down-regulation of histone methylation of H3K9, up-regulation of histone acetylation of H3K9 and global H3. SUV39H1 might be a new target for cancer therapy.
研究小干扰RNA（siRNA）沉默异染色质蛋白3-9同源物1（SUV39H1）基因对急性髓系白血病细胞系KG-1细胞增殖、抑癌基因p15表达及组蛋白修饰的影响，探索白血病新的治疗靶点。
体外合成SUV39H1基因特异性siRNA，通过脂质体2000转染至KG-1细胞。采用RT-PCR和Western blot检测SUV39H1 mRNA和蛋白。用MTS法检测SUV39H1 siRNA对细胞生长的影响。采用Western blot检测抑癌基因p15的表达、H3K9组蛋白甲基化以及H3、H3K9、H3K14、H3K27和H4组蛋白乙酰化情况。
SUV39H1特异性siRNA以浓度依赖性方式显著抑制SUV39H1 mRNA表达。SUV39H1 siRNA抑制KG-1细胞增殖。分别用30、60、120和240 nmol/L的SUV39H1 siRNA转染48小时后，增殖抑制率分别为（23.57±1.98）%、（48.69±1.84）%、（62.69±1.61）%和（81.06±3.22）%。用30、60和120 nmol/L的SUV39H1 siRNA处理48小时后，与对照组相比，SUV39H1 siRNA使组蛋白三甲基化-H3K9下调25%、33%和49%，同时使组蛋白乙酰化H3K9上调1.83、2.16和3.07倍，使整体组蛋白H3上调1.35、1.87和2.37倍，但H3K14、H3K27和H4组蛋白乙酰化未见变化。SUV39H1 siRNA处理后p15表达上调1.52、2.89和3.08倍。
沉默SUV39H1基因可通过下调H3K9组蛋白甲基化、上调H3K9和整体H3组蛋白乙酰化诱导p15重新表达并抑制细胞增殖。SUV39H1可能是癌症治疗的新靶点。
