Li Liming, Xu Cui, Long Jia, Shen Danbei, Zhou Wuqing, Zhou Qiyan, Yang Jia, Jiang Mingjun
Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China.
Oncotarget. 2015 Sep 15;6(27):23930-43. doi: 10.18632/oncotarget.4525.
In SiHa and CaSki cells, E6 and E7-targeting shRNA specifically and effectively knocked down human papillomavirus (HPV) 16 E6 and E7 at the transcriptional level, reduced the E6 and E7 mRNA levels by more than 80% compared with control cells that expressed a scrambled-sequence shRNA. E6 and E7 repression resulted in down-regulation of DNA methyltransferase mRNA and protein expression, decreased DNA methylation and increased mRNA expression levels of tumor suppressor genes, induced a certain apoptosis and inhibited proliferation in E6 and E7 shRNA-infected SiHa and CaSki cells compared with the uninfected cells. Repression of E6 and E7 oncogenes resulted in restoration of DNA methyltransferase suppressor pathways and induced apoptosis in HPV16-positive cervical carcinoma cell lines. Our findings suggest that the potential carcinogenic mechanism of HPV16 through influencing DNA methylation pathway to activate the development of cervical cancer exist, and maybe as a candidate therapeutic strategy for cervical and other HPV-associated cancers.
在SiHa和CaSki细胞中,靶向E6和E7的短发夹RNA(shRNA)在转录水平上特异性且有效地敲低了人乳头瘤病毒(HPV)16型的E6和E7,与表达乱序序列shRNA的对照细胞相比,E6和E7的mRNA水平降低了80%以上。E6和E7的抑制导致DNA甲基转移酶mRNA和蛋白表达下调,DNA甲基化减少,肿瘤抑制基因的mRNA表达水平增加,与未感染细胞相比,在E6和E7 shRNA感染的SiHa和CaSki细胞中诱导了一定程度的细胞凋亡并抑制了增殖。E6和E7癌基因的抑制导致DNA甲基转移酶抑制途径的恢复,并在HPV16阳性宫颈癌细胞系中诱导细胞凋亡。我们的研究结果表明,HPV16通过影响DNA甲基化途径激活宫颈癌发展的潜在致癌机制存在,并且可能作为宫颈癌和其他HPV相关癌症的候选治疗策略。