Allyl isothiocyanate, a constituent of cruciferous vegetables, inhibits proliferation of human prostate cancer cells by causing G2/M arrest and inducing apoptosis

Carcinogenesis. 2003 May;24(5):891-7. doi: 10.1093/carcin/bgg023.


Dietary isothiocyanates (ITCs) are highly effective in affording protection against chemically induced cancers in laboratory animals. In the present study, we demonstrate that allyl isothiocyanate (AITC), a constituent of cruciferous vegetables, significantly inhibits proliferation of cultured PC-3 (androgen-independent) and LNCaP (androgen-dependent) human prostate cancer cells in a dose-dependent manner with an IC(50) of approximately 15-17 micro M. On the other hand, survival of a normal prostate epithelial cell line (PrEC) was minimally affected by AITC even at concentrations that were highly cytotoxic to the prostate cancer cells. Reduced proliferation of PC-3 as well as LNCaP cells in the presence of AITC correlated with accumulation of cells in G(2)/M phase and induction of apoptosis. In contrast, AITC treatment failed to induce apoptosis or cause G(2)/M phase arrest in PrEC cells. A 24 h treatment of PC-3 and LNCaP cells with 20 micro M AITC caused a significant decrease in the levels of proteins that regulate G(2)/M progression, including Cdk1 (32-50% reduction), Cdc25B (44-48% reduction) and Cdc25C (>90% reduction). A significant reduction in the expression of cyclin B1 protein (approximately 45%) was observed only in LNCaP cells. A 24 h exposure of PC-3 and LNCaP cells to an apoptosis-inducing concentration of AITC (20 micro M) resulted in a significant decrease (31-68%) in the levels of anti-apoptotic protein Bcl-2 in both cell lines, and approximately 58% reduction in Bcl-X(L) protein expression in LNCaP cells. In conclusion, it seems reasonable to hypothesize that AITC, and possibly other ITCs, may find use in the treatment of human prostate cancers.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Apoptosis / drug effects*
  • Blotting, Western
  • CDC2 Protein Kinase / metabolism
  • Cell Cycle Proteins / metabolism
  • Cell Division / drug effects
  • Cyclin B / metabolism
  • Cyclin B1
  • Epithelial Cells / cytology
  • Epithelial Cells / metabolism
  • G2 Phase / drug effects*
  • Humans
  • Isothiocyanates / pharmacology*
  • Male
  • Mitosis / drug effects*
  • Prostate / cytology
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / pathology*
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Tumor Cells, Cultured
  • Vegetables / chemistry*
  • bcl-X Protein
  • cdc25 Phosphatases / metabolism


  • BCL2L1 protein, human
  • CCNB1 protein, human
  • Cell Cycle Proteins
  • Cyclin B
  • Cyclin B1
  • Isothiocyanates
  • Proto-Oncogene Proteins c-bcl-2
  • bcl-X Protein
  • allyl isothiocyanate
  • CDC2 Protein Kinase
  • CDC25B protein, human
  • CDC25C protein, human
  • cdc25 Phosphatases