Prostratin and 12-deoxyphorbol 13-phenylacetate (dPP) form a new class of protein kinase C activators of unique biological activity. Although they bind to and activate protein kinase C, in mouse skin they either fail to induce typical phorbol ester (PMA) effects (e.g., hyperplasia) or induce only partial response (e.g., inflammation). Furthermore, pretreatment with these agents inhibits a range...