E2F1 and E2F7 differentially regulate KPNA2 to promote the development of gallbladder cancer

Oncogene. 2019 Feb;38(8):1269-1281. doi: 10.1038/s41388-018-0494-7. Epub 2018 Sep 25.

Abstract

Karyopherin alpha 2 (KPNA2) is a nuclear import factor that is elevated in multiple cancers. However, its molecular regulation at the transcriptional levels is poorly understood. Here we found that KPNA2 was significantly upregulated in gallbladder cancer (GBC), and the increased levels were correlated with short survival of patients. Gene knocking down of KPNA2 inhibited tumor cell proliferation and migration in vitro as well as xenografted tumor development in vivo. A typical transcription factor E2F1 associated with its DNA-binding partner DP1 bond to the promoter region of KPNA2 and induced KPNA2 expression. In contrast, an atypical transcription factor E2F7 competed against DP1 and blocked E2F1-induced KPNA2 gene activation. Mutation of the dimerization residues of E2F7 or DNA-binding domain of E2F1 abolished the suppressive effects of E2F7 on KPNA2 gene expression. In addition, KPNA2 mediated nuclear localization of E2F1 and E2F7, where they in turn controlled KPNA2 expression. Taken together, our data provided mechanistic insights into divergently transcriptional regulation of KPNA2, thus pointing to KPNA2 as a potential target for cancer therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Animals
  • Cell Line, Tumor
  • Cell Proliferation / genetics
  • DNA-Binding Proteins / genetics
  • E2F1 Transcription Factor / genetics*
  • E2F7 Transcription Factor / genetics*
  • Female
  • Gallbladder Neoplasms / genetics*
  • Gallbladder Neoplasms / pathology
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Male
  • Mice
  • Middle Aged
  • Neoplasm Staging
  • Transcription Factor DP1 / genetics
  • Xenograft Model Antitumor Assays
  • alpha Karyopherins / genetics*

Substances

  • DNA-Binding Proteins
  • E2F1 Transcription Factor
  • E2F1 protein, human
  • E2F7 Transcription Factor
  • E2F7 protein, human
  • KPNA2 protein, human
  • Transcription Factor DP1
  • alpha Karyopherins