Radiosensitization of head and neck cancer cells by the phytochemical agent sulforaphane

Strahlenther Onkol. 2011 Sep;187(9):575-80. doi: 10.1007/s00066-011-2218-6. Epub 2011 Aug 16.


Background and purpose: Sulforaphane is a naturally occurring compound found in broccoli and other cruciferous vegetables. Recently it gained attention because of its antiproliferative properties in many cancer cell lines. The aim of this study was to investigate whether sulforaphane could act as a radiosensitizer in head and neck squamous cell carcinoma cell lines.

Materials and methods: Four head and neck squamous cell carcinoma cell lines (i.e., (HNSCC) SCC9, SCC25, CAL27, and FADU) were treated with sulforaphane and subsequently irradiated. Then proliferation and clonogenic assays were performed. Apoptosis was detected by flow cytometry. Possible regulation of Akt and Mcl-1 was investigated by western blotting.

Results: Sulforaphane and radiation in combination leads to stronger inhibition of cell proliferation and of clonogenic survival than each treatment method alone. Western blot analysis of Akt and Mcl-1 showed no changed expression.

Conclusion: Sulforaphane is a promising agent in the treatment of head and neck cancer due to its antiproliferative and radio-sensitizing properties. A combination of sulforaphane and radiation decreases clonogenic survival. Apoptosis is not regulated through Akt or the Mcl-1 protein.

MeSH terms

  • Anticarcinogenic Agents / pharmacology*
  • Apoptosis / drug effects*
  • Apoptosis / radiation effects*
  • Blotting, Western
  • Carcinoma, Squamous Cell / pathology*
  • Cell Division / drug effects*
  • Cell Division / radiation effects*
  • Cell Line, Tumor
  • Head and Neck Neoplasms / pathology*
  • Humans
  • Isothiocyanates
  • Myeloid Cell Leukemia Sequence 1 Protein
  • Phytotherapy*
  • Proto-Oncogene Proteins c-akt / analysis
  • Proto-Oncogene Proteins c-bcl-2 / analysis
  • Radiation-Sensitizing Agents / pharmacology*
  • Squamous Cell Carcinoma of Head and Neck
  • Sulfoxides
  • Thiocyanates / pharmacology*
  • Tumor Stem Cell Assay*


  • Anticarcinogenic Agents
  • Isothiocyanates
  • Myeloid Cell Leukemia Sequence 1 Protein
  • Proto-Oncogene Proteins c-bcl-2
  • Radiation-Sensitizing Agents
  • Sulfoxides
  • Thiocyanates
  • Proto-Oncogene Proteins c-akt
  • sulforaphane