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-ABA has an antiproliferative effect on the human carcinoma cell line A431, as measured by different assays. 3-ABA was capable of inhibiting cell growth as well as colony formation, this inhibitory effect is reversible. Morphological analyses showed a series of cellular alterations, such as a remarkable increase of dendritic-like protrusions, quite unusual in epithelial cells, and suggestive of a differentiative triggering. Immunocytochemical studies suggested that a major target of 3-ABA 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 antiproliferative and cytostatic effects as well as cytotoxic and antiapoptotic effects, processes sharing an important involvement of cytoskeleton. These unique characteristics of 3-ABA may be of interest for cancer research.