In this study, we proposed to design effective multi-target anticancer agents based on the chelation of nontoxic metals with ligands that possess anticancer activity. In total, five Sn(ii) pyridine-2-carboxaldehyde thiosemicarbazone complexes are synthesized and their activities are tested. Among these complexes, C5 is found to show the highest cytotoxicity on investigating their structure-activity relationships. In addition, C5 not only exhibits an effective inhibitory effect against tumor growth in vivo, but also suppresses angiogenesis and restricts the metastasis of cancer cells in vitro. Multiple mechanisms underlie the antitumor effect of C5, and they include acting against DNA, inducing apoptosis, and inhibiting the activities of anti-apoptotic Bcl-xL protein, metalloproteinase MMP2 and topoisomerase II.