title: Selenium compounds as therapeutic agents in cancer.
abstract: BACKGROUND
  With cancer cells encompassing consistently higher production of reactive oxygen species (ROS) and with an induced antioxidant defense to counteract the increased basal ROS production, tumors have a limited reserve capacity resulting in an increased vulnerability of some cancer cells to ROS. Based on this, oxidative stress has been recognized as a tumor-specific target for the rational design of new anticancer agents. Among redox modulating compounds, selenium compounds have gained substantial attention due to their promising chemotherapeutic potential.
  
  
  METHODS
  This review aims in summarizing and providing the recent developments of our understanding of the molecular mechanisms that underlie the potential anticancer effects of selenium compounds.
  
  
  CONCLUSIONS
  It is well established that selenium at higher doses readily can turn into a prooxidant and thereby exert its potential anticancer properties. However, the biological activity of selenium compounds and the mechanism behind these effects are highly dependent on its speciation and the specific metabolic pathways of cells and tissues. Conversely, the chemical properties and the main molecular mechanisms of the most relevant inorganic and organic selenium compounds as well as selenium-based nanoparticles must be taken into account and are discussed herein.
  
  
  CONCLUSIONS
  Elucidating and deepening our mechanistic knowledge of selenium compounds will help in designing and optimizing compounds with more specific antitumor properties for possible future application of selenium compounds in the treatment of cancer. This article is part of a Special Issue entitled Redox regulation of differentiation and de-differentiation.
authors.affiliation: Division of Biochemistry, Department of Medical Biochemistry and Biophysics (MBB), Karolinska Institutet, SE-171 77 Stockholm, Sweden. Electronic address: aristi.fernandes@ki.se.
authors.forename: Aristi P
authors.initials: AP
authors.lastname: Fernandes
authors.affiliation: Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Gandin
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects; D006801:Humans; D015394:Molecular Structure; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry; D009369:Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D016566:Organoselenium Compounds / Q000737:chemistry / Q000627:therapeutic use*; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D018036:Selenium Compounds / Q000737:chemistry / Q000627:therapeutic use*
chemical_list: D000970:Antineoplastic Agents; D016566:Organoselenium Compounds; D018036:Selenium Compounds
keywords: Cell death; Chemotherapeutics; Selenium