miR-9-5p靶向抑制Ambra1促进舌癌细胞增殖  

miR-9-5p Promotes the Proliferation of Tongue Cancer Cells by Targeted Suppression of Ambra1

作　　者：陈伟泉[1] 杨洪[1] 谭广谋[1] 黄海燕[1] 廖卫国[1] 黄文喜[1] 温清泉[1] 漆其光[1] 吴迪[1] 

机构地区：[1]广州医科大学附属肿瘤医院头颈科,广州510095

出　　处：《中国生物化学与分子生物学报》2017年第7期719-725,共7页Chinese Journal of Biochemistry and Molecular Biology

摘　　要：miRNAs在肿瘤中异常表达,且与肿瘤的发生发展密切相关。目前发现,miR-9-5p在肿瘤中可能发挥原癌或抑癌效应,功能尚未完全阐述清楚。本文拟探讨miR-9-5p在舌癌中的作用。前期研究中收集10例舌癌组织及配对的癌旁组织,实时荧光定量PCR技术检测后发现,miR-9-5p在舌癌组织中的表达量显著高于癌旁组织,且其在舌癌细胞中的表达量也明显高于正常舌上皮细胞。此外,在舌癌细胞Tca8113中过表达miR-9-5p显著增加细胞的增殖能力。生物信息学预测及双荧光素酶报告基因实验证实,miR-9-5p可直接结合在自噬/苄氯素1调节因子1(activating molecule in beclin1-regulated autophagy,Ambra1)的3'-UTR区域,靶向抑制Ambra1表达。Western印迹结果证实过表达miR-9-5p降低Ambra1的表达,反之亦然。Ambra1在舌癌细胞中的表达量显著低于正常舌上皮细胞。Brd U实验证实在舌癌细胞SCC-25中过表达Ambra1可显著抑制其增殖能力;相反,使用siRNA技术沉默Ambra1能够显著促进Tca8113细胞的增殖。在干预miR-9-5p的细胞中同时干预Ambra1的表达,结果发现Ambra1可显著逆转miR-9-5p对舌癌细胞增殖的促进作用。总之,miR-9-5p在舌癌中可能发挥原癌基因样作用,通过直接靶向抑制Ambra1表达进而促进舌癌细胞发生增殖。miRNAs are aberrantly expressed in tumors,and are closely related with tumorigenesis and progression. The roles of miR-9-5p in tumors are not very clear,as evidence shows that miR-9-5p functions as either an oncogene or a suppressor in tumors. We aimed to explore its function in the tongue cancer. First,qRT-PCR assays were used to detect miR-9-5p expression levels in ten cases of tongue cancer and normal tissues. The result showed that miR-9-5p was highly expressed in tongue cancer tissues,compared with the normal tissues. Similarly,miR-9-5p was much higher in tongue cancer cells than wild-type tongue epithelial cells. Furthermore,the proliferation of Tca8113 cells was remarkably enhanced by overexpression of miR-9-5p. Bioinformatics analysis combined with dual luciferase assays demonstrated that miR-9-5p directly bound to the 3＇-UTR of activating molecule in beclin1-regulated autophagy（ Ambra1） and inhibited its expression. Western blotting assays suggested that overexpression of miR-9-5p down-regulated Ambra1,while knocking down of miR-9-5p did the opposite. Ambra1 waslowly expressed in the tongue cancer cell line SCC-25,compared with wild-type tongue epithelial cells.Brd U assays indicated that overexpressing Ambra1 markedly inhibited proliferation of SCC-25 cells. On the contrary,knocking down Ambra1 by siRNAs promoted proliferation of SCC-25 cells. Finally,we simultaneously modulated miR-9-5p and Ambra1 expression in tongue cancer cells,and found that Ambra1 overexpression could significantly reverse the proliferation of tongue cancer cells with miR-9-5p.Taken together,these data suggested that miR-9-5p might play an oncogenic role in tongue cancers,and silencing miR-9-5p promoted tongue cancer cell proliferation via directly targeting Ambra1.

关 键 词：miR-9-5p 自噬/苄氯素1调节因子1 舌癌 增殖 

分 类 号：R739.86[医药卫生—肿瘤]