title: Simultaneous modulation of multidrug resistance and antiapoptotic cellular defense by MDR1 and BCL-2 targeted antisense oligonucleotides enhances the anticancer efficacy of doxorubicin.
abstract: OBJECTIVE
  To enhance the anticancer efficacy of an established drug by the simultaneous suppression of pump and nonpump cellular resistance.
  
  
  METHODS
  Multidrug resistant human ovarian (A2780/AD) and breast (MCF-7/AD) cancer cells were used. Doxorubicin (DOX) and antisense oligonucleotides (ASO) targeted to MDR1 and BCL-2 mRNA were combined in a solution within one liposomal drug delivery system (LDDS) in different combination series. Ten series of experiments were performed. In each series cells were incubated with 12 to 45 concentrations of free DOX and different liposomal formulations over a period of 6 to 48 h. Cytotoxicity, apoptosis induction, caspases, MDR1., BCL-2, and APAF-1 genes, P-glycoprotein, and BCL-2 protein were studied.
  
  
  RESULTS
  The combination of DOX and ASO targeted to MDR1 and BCL-2 mRNA in one LDDS exhibited a dramatic increase in the anticancer action of DOX. As a result of the simultaneous suppression of pump and nonpump cellular resistance by the inhibition of P-glycoprotein and BCL-2 protein synthesis, a significant increase in the activation of caspases and apoptosis was observed.
  
  
  CONCLUSIONS
  The simultaneous suppression of multidrug resistance and antiapoptotic cellular defense significantly enhanced the anticancer activity of DOX. Therefore, the proposed DDS combination may potentially be used in the treatment of multidrug-resistant ovarian and breast cancers.
authors.affiliation: Department of Pharmaceutics, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.
authors.forename: Refika I
authors.initials: RI
authors.lastname: Pakunlu
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Cook
authors.forename: Tamara
authors.initials: T
authors.lastname: Minko
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000096:biosynthesis / Q000235:genetics*; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D053477:Apoptotic Protease-Activating Factor 1; D015153:Blotting, Western; D053148:Caspase 3; D053453:Caspase 9; D020169:Caspases / Q000096:biosynthesis / Q000235:genetics; D004317:Doxorubicin / Q000008:administration & dosage / Q000494:pharmacology*; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D008081:Liposomes; D020319:Oligodeoxyribonucleotides, Antisense / Q000494:pharmacology*; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014407:Tumor Cells, Cultured
chemical_list: C506592:APAF1 protein, human; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D053477:Apoptotic Protease-Activating Factor 1; D008081:Liposomes; D020319:Oligodeoxyribonucleotides, Antisense; D011506:Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D004317:Doxorubicin; C505407:CASP3 protein, human; C506433:CASP9 protein, human; D053148:Caspase 3; D053453:Caspase 9; D020169:Caspases