Water-soluble Ru(II)-anethole compounds with promising cytotoxicity toward the human gastric cancer cell line AGS

Abstract Aims Ruthenium-based compounds exhibit critical biochemical properties making them suitable for diverse pharmacological applications. The aim of this work was to study the anticancer effects of three ruthenium complexes on a human gastric cancer cell line. Main methods We synthetized three [Ru(η 6 -anethole)(en)X]PF 6 complexes, where (en) is ethylenediamine and X is Cl ( 1 ), Br ( 2 ) or I ( 3 ), which were then evaluated by MTT assay, RT-qPCR and flow cytometry on the human gastric cancer cell line AGS. Key findings Compound 3 exhibited the highest cytotoxicity (IC 50  = 11.27 ± 1.08 μM) of the series, with an activity almost three-fold more potent than the commercial drug cisplatin, and also revealed a 4.5-fold less potent cytotoxicity in the human normal gastric cell line GES-1. The exchange of the halogen (Cl, Br or I) on the organometallic compound slightly alters its solubility in PBS and lipophilicity (expressed as Log P). Studies of gene expression revealed that compound 3 induces a significant overexpression of the pro-apoptotic genes Caspase-3, PUMA and DIABLO in the gastric cancer cell line AGS after 6 h. In contrast, only PUMA was significantly overexpressed in the normal gastric cell line GES-1. Compound 3 induced the activation of multiple caspases in AGS cells: a sign of apoptosis. Characterization via single-crystal X-ray diffraction for compound 3 confirmed the key structural features for this type of organometallic complexes. Significance Our data suggests that compound 3 may be an interesting anticancer molecule for the treatment of gastric cancer.