A possible anti-proliferative and anti-metastatic effect of irradiated riboflavin in solid tumours.
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.
de Souza Queiroz
Karla Cristiana
KC
Departamento de Bioquímica, Universidade Estadual de Campinas, Brazil.
Zambuzzi
Willian Fernando
WF
Santos de Souza
Ana Carolina
AC
da Silva
Rodrigo Augusto
RA
Machado
Daisy
D
Justo
Giselle Zenker
GZ
Carvalho
Hernandes F
HF
Peppelenbosch
Maikel P
MP
Ferreira
Carmen Veríssima
CV
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D020169:Caspases / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured / Q000187:drug effects; D022781:Hepatocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D008297:Male; D009376:Neoplasms, Hormone-Dependent / Q000188:drug therapy* / Q000556:secondary; D017319:Photosensitizing Agents / Q000494:pharmacology*; D011467:Prostate / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D051381:Rats; D012256:Riboflavin / Q000494:pharmacology*
D017319:Photosensitizing Agents; D020169:Caspases; D012256:Riboflavin