POLY(ADP-RIBOSYLATION) PROCESSING AS A TARGET FOR THE ANTITUMOR EFFECTS OF THE CELL DIFFERENTIATING AGENT, HEXAMETHYLENEBISACETAMIDE, AND THE N6-SUBSTITUTED ADENOSINES

The cellular process regulating the post-translational poly(ADP-ribosylation) of various nuclear acceptor proteins is discussed in relation to its significance as a target for cancer chemotherapy; and with particular reference to the mechanism underlying the anti-tumor effects of the cell differentiating agent, hexamethylenebisacetamide. Of especial note are the influences which may be exerted on tumor cells expressing certain major types of oncogenically-activated cellular proto-oncogenes (oncogenes). A basis for a pharmacological approach to tumor therapy is further proposed from considerations of the action of a class of anti-tumor agents, the N6-substituted adenosines, by reason of their possible effects on poly(ADP-ribosylation) processing, as well as on other cellular processes of relevance for tumor therapy.