title: Efficacy of CR3294, a new benzamidine derivative, in the prevention of 5-fluorouracil-induced gastrointestinal mucositis and diarrhea in mice.
abstract: OBJECTIVE
  Gastrointestinal mucositis, commonly associated with diarrhea, is a dose-limiting toxicity of chemotherapy. The new benzamidine derivative CR3294 reduces tissue damage in animal models of intestinal inflammation. Thus, we tested whether CR3294 had the potential to prevent chemotherapy-induced mucositis.
  
  
  METHODS
  In tests on isolated cells, reactive oxygen species (ROS) formation and cytokine release were measured by chemiluminescence and immunoassays, respectively. In studies in vivo, BDF1 mice were given oral CR3294 (2.5-20 mg/kg) for 3 days before receiving 5-fluorouracil. Intestinal crypt survival, cell apoptosis and proliferation, and diarrhea score were assessed. Additionally, nude mice bearing tumor xenografts were treated with CR3294 and/or 5-fluorouracil, and tumor growth was monitored.
  
  
  RESULTS
  CR3294 significantly inhibited cytokine release from stimulated leukocytes at concentrations similar to the IC(50) (2.9 +/- 0.2 muM) for ROS production by these cells. Consistent with these molecular findings, CR3294 dose-dependently protected the intestinal mucosa against 5-fluorouracil-induced toxicity in a mouse model of mucositis. The number of surviving crypts per cross-section in mice receiving 20 mg/kg CR3294 was 2.8-fold that in vehicle-treated animals (18.1 +/- 1.9 vs. 6.5 +/- 0.9, P < 0.001). Moreover, CR3294 decreased the cumulative diarrhea score by 50%, reduced by nearly 70% the incidence of severe episodes, and increased by 3-fold the number of mice without diarrhea. CR3294 neither affected the growth of tumor xenografts nor protected tumors from the cytotoxic activity of 5-fluorouracil.
  
  
  CONCLUSIONS
  This study demonstrates that CR3294 acts on key molecular targets to reduce the signs of mucositis and the occurrence of diarrhea in mice exposed to the chemotherapy drug 5-fluorouracil.
authors.affiliation: Department of Pharmacology and Toxicology, Rottapharm, Monza, Italy.
authors.forename: Ornella
authors.initials: O
authors.lastname: Letari
authors.forename: Catherine
authors.initials: C
authors.lastname: Booth
authors.forename: Albino
authors.initials: A
authors.lastname: Bonazzi
authors.forename: Paolo
authors.initials: P
authors.lastname: Garofalo
authors.forename: Francesco
authors.initials: F
authors.lastname: Makovec
authors.forename: Lucio C
authors.initials: LC
authors.lastname: Rovati
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Caselli
mesh_terms: D000578:Amidines / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology / Q000633:toxicity*; D016207:Cytokines / Q000187:drug effects / Q000378:metabolism; D003967:Diarrhea / Q000139:chemically induced / Q000517:prevention & control*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005260:Female; D005472:Fluorouracil / Q000494:pharmacology / Q000633:toxicity*; D020128:Inhibitory Concentration 50; D007413:Intestinal Mucosa / Q000187:drug effects / Q000473:pathology; D049449:Luminescence; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D052016:Mucositis / Q000139:chemically induced / Q000517:prevention & control*; D017382:Reactive Oxygen Species; D013890:Thiourea / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D023041:Xenograft Model Antitumor Assays
chemical_list: D000578:Amidines; D000964:Antimetabolites, Antineoplastic; C534043:CR 3294; D016207:Cytokines; D017382:Reactive Oxygen Species; D013890:Thiourea; D005472:Fluorouracil