title: Characterization of a quantitative assay for the in vitro transformation of normal human diploid fibroblasts to anchorage independence by chemical carcinogens.
abstract: We have characterized an assay for the quantitative measurement of the frequency of conversion to anchorage-independent growth of N-acetoxy-2-acetylaminofluorene-treated normal human diploid fibroblasts. We investigated the effects of the following parameters on the absolute number and on the frequency of anchorage-independent colonies scored: (a) the number of cells seeded per dish; (b) the type of posttreatment medium; (c) the number of population doublings allowed posttreatment prior to seeding in suspension; and (d) the carcinogen dose. The assay was linear over the range of 1.9 X 10(3) to 3.8 X 10(4) cells seeded per 6-mm dish for both total colonies scored and the induced frequency of anchorage-independent growth. The medium used posttreatment affected both the frequency and the kinetics of appearance of the anchorage-independent phenotype. The number of population doublings and the number of days allowed posttreatment prior to assaying for anchorage-independent growth potential also influenced the frequency of recovery of this phenotype. Under standardized conditions, the assay yielded a dose-response relationship for transformation to anchorage independence over the concentration range of 0 to 10 microM N-acetoxy-2-acetylaminofluorene.
mesh_terms: D015073:2-Acetylaminofluorene / Q000031:analogs & derivatives*; D000099:Acetoxyacetylaminofluorene / Q000494:pharmacology*; D002448:Cell Adhesion / Q000187:drug effects*; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003470:Culture Media; D003584:Cytological Techniques; D004171:Diploidy; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects* / Q000648:ultrastructure; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010641:Phenotype; D012867:Skin
chemical_list: D003470:Culture Media; D000099:Acetoxyacetylaminofluorene; D015073:2-Acetylaminofluorene