E2F1-regulated long non-coding RNA RAD51-AS1 promotes cell cycle progression, inhibits apoptosis and predicts poor prognosis in epithelial ovarian cancer

Sci Rep. 2017 Jun 30;7(1):4469. doi: 10.1038/s41598-017-04736-z.

Abstract

Long non-coding RNA RAD51 antisense RNA 1 (RAD51-AS1, also known as TODRA) has been shown to be down-regulated by E2F1, a key cell cycle and apoptosis regulator, in breast cancer. Little is known regarding the role of RAD51-AS1 in disease. Here, we investigate the role of RAD51-AS1 in epithelial ovarian cancer (EOC). Using luciferase reporter and chromatin immunoprecipitation experiments, we verified RAD51-AS1 as a target of E2F1 under negative regulation in EOC. We then examined RAD51-AS1 expression in EOC samples using in situ hybridization (ISH). RAD51-AS1 was localized to the nucleus and found to be a critical marker for clinical features that significantly correlated with poor survival in EOC patients. RAD51-AS1 was also an independent prognostic factor for EOC. Overexpression of RAD51-AS1 promoted EOC cell proliferation, while silencing of RAD51-AS1 inhibited EOC cell proliferation, delayed cell cycle progression and promoted apoptosis in vitro and in vivo. RAD51-AS1 may participate in carcinogenesis via regulation of p53 and p53-related genes. Our study highlights the role of RAD51-AS1 as a prognostic marker of EOC. Based on its regulation of the tumor suppressor p53, RAD51-AS1-based therapy may represent a viable therapeutic option for EOC in the near future.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Apoptosis / genetics
  • Carcinoma, Ovarian Epithelial / genetics*
  • Carcinoma, Ovarian Epithelial / metabolism*
  • Carcinoma, Ovarian Epithelial / mortality
  • Carcinoma, Ovarian Epithelial / pathology
  • Cell Cycle / genetics
  • Cell Line, Tumor
  • E2F1 Transcription Factor / metabolism*
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Gene Knockdown Techniques
  • Humans
  • Middle Aged
  • Neoplasm Grading
  • Neoplasm Staging
  • Prognosis
  • Protein Binding
  • Protein Transport
  • RNA, Antisense / genetics*
  • RNA, Long Noncoding / genetics*
  • Rad51 Recombinase / genetics*
  • Rad51 Recombinase / metabolism
  • Tumor Burden
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • E2F1 Transcription Factor
  • E2F1 protein, human
  • RNA, Antisense
  • RNA, Long Noncoding
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • Rad51 Recombinase