ANTIPROLIFERATIVE ACTIVITY OF 3-AMINOBENZAMIDE IN A431 CARCINOMA-CELLS IS ASSOCIATED WITH A TARGET EFFECT ON CYTOSKELETON

3-Aminobenzamide (3-ABA) is an inhibitor of poly(ADP-ribose)polymerase (PARP), an enzyme involved in several cellular processes, and exerts its effects by acting at the cytoskeleton level. Here we show that 3-A BA has an antiproliferative effect on the human carcinoma cell line A4 31, as measured by different assays. 3-ABA was capable of inhibiting c ell growth as well as colony formation, this inhibitory effect is reve rsible. Morphological analyses showed a series of cellular alterations , such as a remarkable increase of dendritic-like protrusions, quite u nusual in epithelial cells, and suggestive of a differentiative trigge ring. Immunocytochemical studies suggested that a major target of 3-AB A was indeed the cytoskeleton. These data, together with those of the literature, indicate that 3-ABA, depending on cell histotype and drug concentration, is a versatile drug capable of exerting antiproliferati ve and cytostatic effects as well as cytotoxic and antiapoptotic effec ts, processes sharing an important involvement of cytoskeleton. These unique characteristics of 3-ABA may be of interest for cancer research . (C) 1996 Academic Press, Inc.