Transcriptome analysis reveals a dynamic and differential transcriptional response to sulforaphane in normal and prostate cancer cells and suggests a role for Sp1 in chemoprevention

Mol Nutr Food Res. 2014 Oct;58(10):2001-13. doi: 10.1002/mnfr.201400269. Epub 2014 Aug 5.

Abstract

Scope: Epidemiological studies provide evidence that consumption of cruciferous vegetables, like broccoli, can reduce the risk of cancer development. Sulforaphane (SFN) is a phytochemical derived from cruciferous vegetables that induces anti-proliferative and pro-apoptotic responses in prostate cancer cells, but not in normal prostate cells. The mechanisms responsible for this cancer-specific cytotoxicity remain unclear.

Methods and results: We utilized RNA sequencing and determined the transcriptomes of normal prostate epithelial cells, androgen-dependent prostate cancer cells, and androgen-independent prostate cancer cells treated with SFN. SFN treatment dynamically altered gene expression and resulted in distinct transcriptome profiles depending on prostate cell line. SFN also down-regulated the expression of genes that were up-regulated in prostate cancer cells. Network analysis of genes altered by SFN treatment revealed that the transcription factor Specificity protein 1 (Sp1) was present in an average of 90.5% of networks. Sp1 protein was significantly decreased by SFN treatment in prostate cancer cells and Sp1 may be an important mediator of SFN-induced changes in expression.

Conclusion: Overall, the data show that SFN alters gene expression differentially in normal and cancer cells with key targets in chemopreventive processes, making it a promising dietary anti-cancer agent.

Keywords: Chemoprevention; Prostate cancer; RNA sequencing; Specificity protein 1; Sulforaphane.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anticarcinogenic Agents / adverse effects
  • Anticarcinogenic Agents / pharmacology*
  • Carcinogenesis / drug effects
  • Cell Line, Tumor
  • Cells, Cultured
  • Chemoprevention
  • Dietary Supplements / adverse effects
  • Gene Expression Regulation, Neoplastic / drug effects
  • Gene Silencing
  • Humans
  • Isothiocyanates / adverse effects
  • Isothiocyanates / pharmacology*
  • Male
  • Neoplasm Proteins / antagonists & inhibitors*
  • Neoplasm Proteins / genetics
  • Neoplasm Proteins / metabolism
  • Prostate / cytology
  • Prostate / drug effects*
  • Prostate / metabolism
  • Prostatic Neoplasms / drug therapy*
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms, Castration-Resistant / drug therapy
  • Prostatic Neoplasms, Castration-Resistant / metabolism
  • RNA, Small Interfering
  • Sp1 Transcription Factor / antagonists & inhibitors*
  • Sp1 Transcription Factor / genetics
  • Sp1 Transcription Factor / metabolism
  • Sulfoxides
  • Transcriptome / drug effects*

Substances

  • Anticarcinogenic Agents
  • Isothiocyanates
  • Neoplasm Proteins
  • RNA, Small Interfering
  • Sp1 Transcription Factor
  • SP1 protein, human
  • Sulfoxides
  • sulforaphane