title: Application of a microsomal drug activation system in a human tumor cloning assay.
abstract: A commercially available preparation of livers from rats can be used to activate cyclophosphamide and DTIC in vitro. This activation can be done in such a way as to have utility in a soft agar cloning assay. The commercial S-9 fraction contains one or more factors which exert a direct inhibitory effect on the ability of five human tumors and three different cell lines to form colonies in soft agar. The inhibition is eliminated by heating to 56 degrees C and is markedly diminished by low speed centrifugation at 7000 g. This commercially available liver preparation may provide a useful tool to extend the feasibility of clonogenic assays to standard drugs and new investigational drugs whose antitumor activity is dependent upon microsomal activation.
mesh_terms: D000818:Animals; D002460:Cell Line; D003520:Cyclophosphamide / Q000494:pharmacology*; D003606:Dacarbazine / Q000494:pharmacology*; D004317:Doxorubicin / Q000494:pharmacology; D005260:Female; D006801:Humans; D007739:L Cells / Q000187:drug effects; D008862:Microsomes, Liver / Q000187:drug effects*; D014411:Neoplastic Stem Cells / Q000187:drug effects*; D051381:Rats; D013234:Stem Cells / Q000187:drug effects*; D014410:Tumor Stem Cell Assay
chemical_list: D003606:Dacarbazine; D004317:Doxorubicin; D003520:Cyclophosphamide