A possible anti-proliferative and anti-metastatic effect of irradiated riboflavin in solid tumours

Cancer Lett. 2007 Dec 8;258(1):126-34. doi: 10.1016/j.canlet.2007.08.024.

Abstract

Riboflavin is a potent photosensitizer as well as part of the vitamin B complex. Recently we demonstrated that the products generated by irradiation of riboflavin have potential as anti-leukaemic therapy. The possible action, however, of the riboflavin photoproducts in solid cancers has not been addressed. Hence, we investigated the effects of irradiated riboflavin on androgen-independent human prostate cancer cells (PC3), a known model for solid tumour cells with an exceptional resistance to therapy. Our results show that riboflavin photoproducts are cytotoxic to these cells in a FasL-Fas-dependent manner. Furthermore, irradiated riboflavin inhibited matrix-degrading proteases, caused downregulation of VEGF and upregulation of TIMP1 suggesting anti-metastatic potential. Together, these results show that the anti-neoplastic action of riboflavin photoproducts is not limited to haematological malignancies, warranting clinical studies in solid tumours.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Blotting, Western
  • Caspases / metabolism
  • Cell Proliferation / drug effects*
  • Cells, Cultured / drug effects
  • Hepatocytes / cytology
  • Hepatocytes / drug effects
  • Hepatocytes / metabolism
  • Humans
  • Male
  • Neoplasms, Hormone-Dependent / drug therapy*
  • Neoplasms, Hormone-Dependent / secondary
  • Photosensitizing Agents / pharmacology*
  • Prostate / cytology
  • Prostate / drug effects
  • Prostate / metabolism
  • Prostatic Neoplasms / drug therapy*
  • Rats
  • Riboflavin / pharmacology*

Substances

  • Photosensitizing Agents
  • Caspases
  • Riboflavin