title: Controlled delivery of BID protein fused with TAT peptide sensitizes cancer cells to apoptosis.
abstract: BACKGROUND
  Low cellular level of BID is critical for viability of numerous cancer cells. Sensitization of cells to anticancer agents by BID overexpression from adenovirus or pcDNA vectors is a proposed strategy for cancer therapy; however it does not provide any stringent control of cellular level of BID. The aim of this work was to examine whether a fusion of BID with TAT cell penetrating peptide (TAT-BID) may be used for controlled sensitization of cancer cells to anticancer agents acting through death receptors (TRAIL) or DNA damage (camptothecin). Prostate cancer PC3 and LNCaP, non-small human lung cancer A549, and cervix carcinoma HeLa cells were used in the study.
  
  
  METHODS
  Uptake of TAT-BID protein by cells was studied by quantitative Western blot analysis of cells extracts. Cells viability was monitored by MTT test. Apoptosis was detected by flow cytometry and cytochrome c release assay.
  
  
  RESULTS
  TAT-BID was delivered to all cancer cells in amounts depending on time, dose and the cell line. Recombinant BID sensitized PC3 cells to TRAIL or, to lesser extent, to camptothecin. Out of remaining cells, TAT-BID sensitized A549, and only slightly HeLa cells to TRAIL. None of the latter cell lines were sensitized to camptothecin. In all cases the mutant not phosphorylable by CK2 (TAT-BIDT59AS76A) was similarly efficient in sensitization as the wild type TAT-BID.
  
  
  CONCLUSIONS
  TAT-BID may be delivered to cancer cells in controlled manner and efficiently sensitizes PC3 and A549 cells to TRAIL. Therefore, it may be considered as a potential therapeutic agent that enhances the efficacy of TRAIL for the treatment of prostate and non-small human lung cancer.
authors.forename: Emilia Joanna
authors.initials: EJ
authors.lastname: Orzechowska
authors.forename: Ewa
authors.initials: E
authors.lastname: Kozlowska
authors.forename: Alicja
authors.initials: A
authors.lastname: Czubaty
authors.forename: Piotr
authors.initials: P
authors.lastname: Kozlowski
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Staron
authors.affiliation: Department of Molecular Biology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland. jtd@biol.uw.edu.pl.
authors.forename: Joanna
authors.initials: J
authors.lastname: Trzcinska-Danielewicz
mesh_terms: D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics*; D051023:BH3 Interacting Domain Death Agonist Protein / Q000235:genetics*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D045304:Cytochromes c / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D010446:Peptide Fragments / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000235:genetics* / Q000494:pharmacology*; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000494:pharmacology; D013997:Time Factors; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000235:genetics*
chemical_list: D051023:BH3 Interacting Domain Death Agonist Protein; D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D053221:TNF-Related Apoptosis-Inducing Ligand; D054322:tat Gene Products, Human Immunodeficiency Virus; D045304:Cytochromes c