DNA甲基化抑制剂5-氮杂-2’-脱氧胞苷抗癌新机制初探  

Novel mechanism underlying anticancer effect of methyltransferase inhibitor 5-aza-2'-deoxycytidine

作　　者：袁君婷 韩笑[1,3] 吕贝[1,4] 胡序明[1,3] 耿拓宇[1,3] 崔恒宓[1,3] 

机构地区：[1]扬州大学表观遗传学及表观基因组学研究所,江苏扬州225009 [2]扬州大学生物科学和技术学院,江苏扬州225009 [3]扬州大学动物科学与技术学院,江苏扬州225009 [4]扬州大学医学院,江苏扬州225009

出　　处：《肿瘤》2017年第3期201-207,共7页Tumor

基　　金：国家自然科学基金资助项目(编号:91540117;81372237);国家"十三五"重点研发计划项目(编号:2016YFC1303604)~~

摘　　要：目的:探讨5-氮杂-2’-脱氧胞苷(5-aza-2’-deoxycytidine,AZA)抗癌作用的新机制,即AZA是否通过激活反义RNA来抑制癌相关基因的表达。方法:从已建双链RNA文库中挑选出6个基因,即第10号染色体缺失的磷酸酶及张力蛋白同源物基因(phosphatase and tensin homolog deleted on chromosome ten,PTEN)、信号转导及转录激活因子1(signal transducers and activators of transcription 1,STAT1)基因、Ras样原癌基因B(Ras-like proto-oncogene B,RALB)、MET、CD44和热休克蛋白A4(heat-shock protein A4,HSPA4)基因。用DMSO(作为对照组)或溶于DMSO的AZA分别处理人肝癌细胞Hep G2,采用链特异性RT-PCR及实时荧光定量PCR法检测上述6个基因的正反义RNA的表达。AZA促进抑癌基因PTEN和先天免疫相关基因STAT 1的正义RNA表达(P<0.01,P<0.001),而癌相关基因CD 44和HSPA 4的正义RNA表达均受到明显抑制(P值均<0.01)。结论:AZA通过激活反义RNA的表达,诱导抑癌基因和先天免疫基因的表达,并抑制癌相关基因的表达,从而发挥其抗癌作用。Objective： To reveal a novel mechanism by which 5-aza-L - deoxycytidine （AZA） plays its anticancer role, and whether AZA can inhibit the expressions of cancer-associated genes by activating their antisense RNAs. Methods： Six genes were chosen which were previously obtained from those having antisense RNAs, by sequencing a double-stranded RNA library. The selected genes included phosphatase and tensin homolog deleted on chromosome ten （PTEN）, signal transducers and activators of transcription 1 （STAT1）, Ras-like proto-oncogene B （RALB）, MET, CD44 and heat-shock protein A4 （HSPA4）. The human hepatocellular carcinoma HepG2 cells were treated with AZA （dissolved in DMSO） or DMSO （as the control）. The expressions of sense and antisense RNAs for the selected genes were detected by strand-specific RT-PCR and real-time fluorescent quantitative PCR, respectively. Results： The antisense RNAs of all 6 genes were activated by AZA treatment （all P 〈 0.01）. On the other hand, AZA also induced the expressions of tumor suppressor gene PTEN and innate immunity-related gene HSPA4 （P 〈 0.01, P 〈 0.001）. In contrast, the expressions of cancer-related genes, CD44 and HSPA4, were obviously inhibited by AZA treatment （both P 〈 0.01）. Conclusion： AZA can activate the antisense RNAs, so as to promote the expressions of tumor suppressor genes and innate immunity- related genes, but to inhibit the expressions of cancer-associated genes; which may be the novel mechanism underlying anticancer effect of AZA.

关 键 词：肝肿瘤 脱氧胞苷 RNA 反义 基因表达调控 肿瘤 

分 类 号：R735.7[医药卫生—肿瘤]