Abstract
Activation of the c-myc proto-oncogene is implicated in the initiation or progression of many vertebrate cancers. In nontransformed cells, the expression of c-myc is induced by growth factors. Studies have indicated that such induction is effected by multiple mechanisms. To study regulation of c-myc expression, a transfection system has been developed in which introduced c-myc genes exhibit serum-responsive activity. The responsiveness assayed is not mediated by increased transcription initiation. Rather, it is effected at a point(s) between transcription and stabilization of the RNA.