title: Methylselenocysteine treatment leads to diselenide formation in human cancer cells: evidence from X-ray absorption spectroscopy studies.
abstract: The selenoamino acids methylselenocysteine (MeSeCys) and selenomethionine (SeMet) have disparate efficacies as anticancer agents. Herein, we use X-ray absorption spectroscopy to determine the chemical form of selenium in human neuroblastoma cells. Cells treated with MeSeCys contain a significant diselenide component, which is absent from SeMet-treated cells and suggests that metabolites of MeSeCys are capable of altering the redox status of the cells. The differences in the speciation of Se in the selenoamino acid-treated cells may provide insight into the differing anticancer activities of MeSeCys and SeMet.
authors.affiliation: School of Chemistry and Physics, The University of Adelaide, SA 5005, Australia.
authors.forename: Claire M
authors.initials: CM
authors.lastname: Weekley
authors.forename: Jade B
authors.initials: JB
authors.lastname: Aitken
authors.forename: Ian F
authors.initials: IF
authors.lastname: Musgrave
authors.forename: Hugh H
authors.initials: HH
authors.lastname: Harris
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D001555:Benzene Derivatives / Q000378:metabolism*; D045744:Cell Line, Tumor; D003545:Cysteine / Q000031:analogs & derivatives* / Q000494:pharmacology; D006801:Humans; D016566:Organoselenium Compounds / Q000378:metabolism* / Q000494:pharmacology*; D018036:Selenium Compounds / Q000378:metabolism; D017279:Selenocysteine / Q000031:analogs & derivatives; D056928:X-Ray Absorption Spectroscopy / Q000379:methods
chemical_list: D000970:Antineoplastic Agents; D001555:Benzene Derivatives; D016566:Organoselenium Compounds; D018036:Selenium Compounds; C442270:selenol; D017279:Selenocysteine; C061132:diphenyldiselenide; D003545:Cysteine; C002979:selenomethylselenocysteine