DITHRANOL (ANTHRALIN) AND L0-BUTYRYL DITHRANOL (BUTANTRONE) DO NOT MORPHOLOGICALLY TRANSFORM CULTURED C3H 10T1 2 C18 MOUSE EMBRYO FIBROBLASTS/

The ability of dithranol and 10-butyryl dithranol to induce morphologi cal cell transformation was studied in cultured C3H 10T1/2 C18 fibrobl asts. The cells were incubated with different concentrations of the te st compounds for 48 h and cultured for 5 weeks thereafter. At the end of the culture period the cultures were fixed, stained and examined fo r the presence of transformed foci. Dithranol and 10-butyryl dithranol did not increase the formation of transformed foci, while the positiv e control compound, 7,12-dimethylbenz(a)anthracene (DMBA), induced a h igh frequency of transformations significantly different from controls . Thus the in vitro cell transformation model with uninitiated C3H 10T 1/2 C18 fibroblasts is not able to detect the weak tumorigenic action of dithranol and 10-butyryl dithranol which has been observed in mouse skin.