New acridone derivatives to target telomerase and oncogenes - an anticancer approach

In this work, two new acridone derivatives, AcridPy and AcridPyMe, were synthesized, for the first time, aiming to evaluate their potential as quadruplex stabilizers and anticancer agents. AcridPy was synthesized through a very straightforward one-pot sequential chemical reaction involving the Heck cross-coupling reaction of (E)-3-iodo-2-(4-methoxystyryl)-1-methylquinolin-4(1H)-one with a vinyl pyridine followed by in situ electrocyclization and oxidation, while the synthesis of AcridPyMe involved an additional N-methylation of the pyridine ring. Their ability to stabilize G-quadruplex DNA structures, which are associated with the regulation of oncogenes, was assessed using biophysical methods. Both compounds demonstrated significant quadruplex stabilization properties, showing selectivity to G-quadruplexes over duplex DNA. Molecular dynamics simulation experiments supported the preferential binding of AcridPyMe to MYC. The cytotoxicity of these derivatives was further evaluated in vitro in two distinct pancreatic tumor cell lines, PanC-1 and MIA PaCa-2, the lung tumor A549 cell line, the melanoma A375 cell line, and the immortalized human keratinocyte HaCaT cell line, through the evaluation of cell viability. For PanC-1 and MIA PaCa-2, the cell cycle dynamics and apoptotic cell death along with colocalization were also evaluated. The results revealed that AcridPyMe exhibited anticancer activity, correlated with its quadruplex stabilization ability and, although not exclusive, nuclear co-localization was observed. These findings suggest that the newly synthesized cationic acridone is a promising candidate for the development of novel anticancer therapies targeting G-quadruplex structures.