title: Celecoxib prevents neuroblastoma tumor development and potentiates the effect of chemotherapeutic drugs in vitro and in vivo.
abstract: OBJECTIVE
  Neuroblastoma is the most common and deadly solid tumor of childhood. Cyclooxygenase-2 is expressed in clinical neuroblastoma tumors and cell lines and inhibitors of this enzyme induce apoptosis in human neuroblastoma cells in vitro and in neuroblastoma xenografts in vivo. We hypothesized that the cyclooxygenase-2-specific inhibitor celecoxib could enhance the cytotoxic effect of chemotherapeutic drugs currently used in neuroblastoma treatment. Furthermore, we investigated if prophylactic treatment with celecoxib could prevent neuroblastoma tumor development in vivo.
  
  
  METHODS
  Neuroblastoma cell cytotoxicity of chemotherapeutic drugs in combination with celecoxib was examined. In vivo, athymic rats carrying established SH-SY5Y xenografts were treated with celecoxib in combination with irinotecan, doxorubicin or etoposide, or with either drug alone. For prevention studies, rats received celecoxib in the diet, 250 to 2,500 ppm, from the time of tumor cell injection.
  
  
  RESULTS
  Celecoxib induced a synergistic or an additive cytotoxic effect in combination with doxorubicin, etoposide, irinotecan or vincristine in vitro. In vivo, treatment with celecoxib in combination with irinotecan or doxorubicin induced a significant growth inhibition of established neuroblastoma tumors. Rats receiving celecoxib in the diet showed a distinct dose-dependent delay in tumor development compared with untreated rats. Plasma levels of celecoxib were comparable with levels obtainable in humans.
  
  
  CONCLUSIONS
  Celecoxib potentiates the antitumor effect of chemotherapeutic drugs currently used in neuroblastoma treatment, which argues for clinical trials combining these drugs. Celecoxib could also be a potential drug for treatment of minimal residual disease.
authors.affiliation: Childhood Cancer Research Unit, Department of Woman and Child Health, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Frida
authors.initials: F
authors.lastname: Ponthan
authors.forename: Malin
authors.initials: M
authors.lastname: Wickström
authors.forename: Helena
authors.initials: H
authors.lastname: Gleissman
authors.forename: Ole M
authors.initials: OM
authors.lastname: Fuskevåg
authors.forename: Lova
authors.initials: L
authors.lastname: Segerström
authors.forename: Baldur
authors.initials: B
authors.lastname: Sveinbjörnsson
authors.forename: Christopher P F
authors.initials: CP
authors.lastname: Redfern
authors.forename: Staffan
authors.initials: S
authors.lastname: Eksborg
authors.forename: Per
authors.initials: P
authors.lastname: Kogner
authors.forename: John I
authors.initials: JI
authors.lastname: Johnsen
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D017209:Apoptosis; D000068579:Celecoxib; D045744:Cell Line, Tumor; D051546:Cyclooxygenase 2 / Q000096:biosynthesis*; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D019394:Ki-67 Antigen / Q000096:biosynthesis; D008297:Male; D009368:Neoplasm Transplantation; D009447:Neuroblastoma / Q000188:drug therapy* / Q000378:metabolism; D011720:Pyrazoles / Q000627:therapeutic use*; D051381:Rats; D011923:Rats, Nude; D013449:Sulfonamides / Q000627:therapeutic use*
chemical_list: D000970:Antineoplastic Agents; D016861:Cyclooxygenase Inhibitors; D019394:Ki-67 Antigen; D011720:Pyrazoles; D013449:Sulfonamides; D051546:Cyclooxygenase 2; D000068579:Celecoxib