title: Epirubicin-[Anti-HER2/neu] Synthesized with an Epirubicin-(C13-imino)-EMCS Analog: Anti-Neoplastic Activity against Chemotherapeutic-Resistant SKBr-3 Mammary Carcinoma in Combination with Organic Selenium.
abstract: OBJECTIVE
  Discover the anti-neoplastic efficacy of epirubicin-(C13-imino)-[anti-HER2/neu] against chemotherapeutic-resistant SKBr-3 mammary carcinoma and delineate the capacity of selenium to enhance it's cytotoxic anti-neoplastic potency.
  
  
  METHODS
  In molar excess, EMCH was combined with epirubicin to create a covalent epirubicin-(C13-imino)-EMCH-maleimide intermediate with sulfhydryl-reactive properties. Monoclonal immunoglobulin selective for HER2/neu was then thiolated with 2-iminothiolane at the terminal ε-amine group of lysine residues. The sulfhydryl-reactive epirubicin-(C13-imino)-EMCH intermediate was then combined with thiolated anti-HER2/neu monoclonal immunoglobulin. Western-blot analysis was utilized to characterize the molecular weight profiles while binding of epirubicin-(C13-imino)-[anti-HER2/neu] to membrane receptors was determined by cell-ELISA utilizing populations of SKBr-3 mammary carcinoma that highly over-expresses HER2/neu complexes. Anti-neoplastic potency of epirubicin-(C13-imino)-[anti-HER2/neu] between the epirubicin-equivalent concentrations of 10-12M and 10-7M was determined by vitality staining analysis with and without the presence of selenium (5 μM).
  
  
  RESULTS
  Epiribucin-(C13-imino)-[anti-HER2/neu] between epirubicin-equivalent concentrations of 10-8M to 10-7M consistently evoked higher anti-neoplastic potency than "free" non-conjugated epirubicin which corresponded with previous investigations utilizing epirubicin-(C3-amide)-[anti-HER2/neu] and epirubicin-(C3-amide)-[anti-EGFR]. Selenium at 5 mM consistently enhanced the cytotoxic anti-neoplastic potency of epirubicin-(C13-imino)-[anti-HER2/neu] at epirubicin equivalent concentrations (10-12 to 10-7 M).
  
  
  CONCLUSIONS
  Epirubicin-(C13-imino)-[anti-HER2/neu] is more potent than epirubicin against chemotherapeutic-resistant SKBr-3 mammary carcinoma and selenium enhances epirubicin-(C13-imino)-[anti-HER2/neu] potency. The methodology applied for synthesizing epirubicin-(C13-imino)-[anti-HER2/neu] is relatively time convenient and has low instrumentation requirements.
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, USA.
authors.forename: Cody P
authors.initials: CP
authors.lastname: Coyne
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, USA.
authors.forename: Toni
authors.initials: T
authors.lastname: Jones
authors.affiliation: Department Organic Chemistry, Mississippi State University, Mississippi State, USA.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Sygula
authors.affiliation: College of Osteopathic Medicine, William Cary University, Hattiesburg, USA.
authors.forename: John
authors.initials: J
authors.lastname: Bailey
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, USA.
authors.forename: Lesya
authors.initials: L
authors.lastname: Pinchuk
keywords: Chemotherapeutic-Resistant Mammary Carcinoma; Epirubicin-(C13-Imino)-[Anti-HER2/neu]; HER2/neu; Selenium; Synthesis