title: MiR-519d facilitates the progression and metastasis of cervical cancer through direct targeting Smad7.
abstract: BACKGROUND
  MicroRNAs (miRNAs) play pivotal roles in the development of various cancer types, including cervical cancer.
  
  
  RESULTS
  In this study, we showed that miR-519d, a miRNA within the chromosome 19 miRNA cluster, was significantly upregulated in cervical cancer tissues, compared with non-tumorous cervical samples. Suppression of miR-519d markedly attenuated the migration and invasion of HeLa and SiHa cervical cancer cells. Additionally, miR-519d inhibited the apoptosis of cervical cancer cells, and the proliferation of cervical cancer cells was also affected following transfection of miR-519d inhibitor. Moreover, we identified Smad7 to be a novel target of miR-519d in cervical cancer cells. MiR-519d matched the 3'-UTR of Smad7 mRNA. Transfection with miR-519d mimics led to apparent downregulation of Smad7 both at the mRNA and protein levels. Luciferase reporter analysis revealed that miR-519d reduced the luciferase activity of Smad7 mRNA 3'-UTR through matching site-dependent manner. And more notably, suppression of Smad7 remarkably restored the migration and invasion of miR-519d-depleted cervical cancer cells.
  
  
  CONCLUSIONS
  Taken together, these findings implicated that miR-519d promoted the progression and metastasis of cervical cancer through targeting Smad7.
authors.affiliation: Institute of Genetic Engineering, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515 Guangdong People's Republic of China.
authors.forename: Jue-Yu
authors.initials: JY
authors.lastname: Zhou
authors.affiliation: Institute of Genetic Engineering, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515 Guangdong People's Republic of China.
authors.forename: Si-Rong
authors.initials: SR
authors.lastname: Zheng
authors.affiliation: Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515 Guangdong People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.affiliation: Institute of Genetic Engineering, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515 Guangdong People's Republic of China.
authors.forename: Rong
authors.initials: R
authors.lastname: Shi
authors.affiliation: Institute of Genetic Engineering, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515 Guangdong People's Republic of China.
authors.forename: Hai-Lang
authors.initials: HL
authors.lastname: Yu
authors.affiliation: Institute of Genetic Engineering, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515 Guangdong People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Wei
keywords: Cervical cancer; Metastasis; MiR-519d; Proliferation; Smad7