title: Anti-ERBb4 targeted therapy combined with radiation therapy in prostate cancer. Results of in vitro and in vivo studies.
abstract: OBJECTIVE
  To evaluate the efficiency of anti ErbB4 targeted therapy combined with irradiation (XRT) over each modality alone in prostate cancer.
  
  
  RESULTS
  Clones with high ErbB4 expression grew faster than those with low ErbB4 expression. XRT inhibited the growth of both expressive and non-expressive ErbB4 cells, while mAb inhibited only high ErbB4-expressing cells. The combination of XRT and mAb resulted in a 30% reduction of the survival of high ErbB4 expressing cells over XRT alone (p = 0.013). In tumor bearing mice the tumor size in the combined arm was 1 mm at 4 weeks compared to 2-3 mm and 4-5 mm in the radiation and mAb arms (p' value of 0.02 and 0.087 respectively).
  
  
  METHODS
  Clones with low and high expression of ErbB4 isolated by a limited dilution technique from an androgen-independent Cl-1 cell line were used. The cells from these clones were exposed to XRT (single dose of 2-6 Gy) and to anti-ErbB4 monoclonal antibody (mAb). The XTT test was used to measure cell survival. In addition, tumor-bearing nude mice were treated either by XRT, mAb or by a combined treatment. Tumor sizes were recorded at given time points.
  
  
  CONCLUSIONS
  Anti ErbB4 combined with XRT is possibly more effective than each modality alone in prostate cancer.
authors.affiliation: Oncology Division, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Akiva
authors.initials: A
authors.lastname: Vexler
authors.forename: Ghalib
authors.initials: G
authors.lastname: Lidawi
authors.forename: Vered
authors.initials: V
authors.lastname: Loew
authors.forename: Itay
authors.initials: I
authors.lastname: Barnea
authors.forename: Victoriya
authors.initials: V
authors.lastname: Karaush
authors.forename: Shahar
authors.initials: S
authors.lastname: Lev-Ari
authors.forename: Alexander
authors.initials: A
authors.lastname: Shtabsky
authors.forename: Rami
authors.initials: R
authors.lastname: Ben-Yosef
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002470:Cell Survival; D003131:Combined Modality Therapy; D004354:Drug Screening Assays, Antitumor; D066246:ErbB Receptors / Q000737:chemistry* / Q000276:immunology; D006801:Humans; D007167:Immunotherapy / Q000379:methods; D008297:Male; D051379:Mice; D008819:Mice, Nude; D011471:Prostatic Neoplasms / Q000276:immunology* / Q000628:therapy*; D066247:Receptor, ErbB-4; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; C587689:ERBB4 protein, human; D066246:ErbB Receptors; C587690:Erbb4 protein, mouse; D066247:Receptor, ErbB-4