OxyFile #53

TI:  In vitro Synergistic Activity of 5-Fluorouracil with Low-
     Dose Ozone against a Chemoresistant Tumor Cell Line and 
     Fresh Human Tumor Cells

DT:  1990

AU:  Kurt S. Zanker, Ronald Kroczek

SO:  Chemotherapy 1990;36:147-154

AB:  We followed the concept that the chemical reactivity of 
     ozone depends upon its oxidative properties.  Activated 
     oxygen species are causally involved in toxicity of certain 
     chemotherapeutic drugs.  We have tested this prediction in 
     human cell cultures either to overcome chemoresistance 
     and/or to increase chemical cytotoxicity.  Our results 
     indicate that ozone in combination with 5-fluorouracil (5-
     FU) makes a 5-FU-resistant cell line susceptible for the 
     combined treatment modality.  Furthermore, ozone acts 
     synergistically or at least additive to chemotherapy in 
     different tumor cell suspensions, derived from the breast 
     and the colon.