Biological function and mechanism of miR-33a in prostate cancer survival and metastasis: via downregulating Engrailed-2.


Journal Article

OBJECTIVE:Recent studies have identified Engrailed-2 (EN-2), a homeobox-containing transcription factor, as a candidate oncogene in prostate cancer (PC). Therapeutic targeting on EN-2, however, is limited because the mechanism underlying EN-2 overexpression in prostatic cancer cells is unknown. This study was to investigate the potential regulatory role of miR-33a on EN-2 expression and explore this signaling axis in ability of prostate cancer survival and metastasis. METHODS:The relative expression of miR-33a and EN-2 in paired prostate cancer tissue and adjacent normal tissue as well as in prostate cancer cell lines, PC3 and DU145, was determined using quantitative real-time PCR or western blot, respectively. Cells survival, migration and invasion were evaluated by assays of MTT, TUNEL and Boyden chamber assays, respectively. Direct regulation of EN-2 by miR-33a was examined by luciferase reporter assay. RESULTS:The data showed that miR-33a was upregulated and EN-2 was downregulated in both prostate cancer tissue and prostate cancer cells. miR-33a overexpression suppresses prostate cancer cell survival and metastasis. miR-33a can directly act on EN-2 expression by binding to 3'UTR of its mRNA. Also, miR-33a negatively regulated EN-2 mRNA and protein expression. In pcDNA-EN-2 and miR-33a mimic co-transfected PC3 and DU145 cells, EN-2 overexpression reverses the anti-cell survival and metastasis actions of miR-33a overexpression. The pivotal role of miR-33a in inhibiting prostate tumor growth was confirmed in xenograft models of prostate cancer. CONCLUSION:Our data suggest that the functional interaction of miR-33a and EN-2 is involved in tumorigenesis of prostate cancer. Also in this process EN-2 serves as a negative responder for miR-33a.

Full Text

Duke Authors

Cited Authors

  • Li, Q; Lu, S; Li, X; Hou, G; Yan, L; Zhang, W; Qiao, B

Published Date

  • May 2017

Published In

Volume / Issue

  • 19 / 5

Start / End Page

  • 562 - 570

PubMed ID

  • 27921232

Pubmed Central ID

  • 27921232

Electronic International Standard Serial Number (EISSN)

  • 1699-3055

International Standard Serial Number (ISSN)

  • 1699-048X

Digital Object Identifier (DOI)

  • 10.1007/s12094-016-1564-3


  • eng