Nuclear Binding of Tritiated Actinomycin in Basal Cell Carcinoma and in Normal Human Epidermis¹

The ability of fixed histological samples from normal epidermis and from basal cell carcinoma to bind actinomycin D-³H was measured by autoradiography. Significantly higher nuclear fixation of the labeled antibiotic was measured in all cases in basal cell carcinoma, fixed with formalin or with alcohol:acetic acid. This suggests that chromatin in the carcinoma is less repressed than in normal basal cells, a conclusion which is in agreement with our present knowledge of this particular type of epidermal tumor, known to be able to evolve towards more or less well-characterized differentiated epidermal adnexae.