Synthesis of Squaramides with Anti-tumor Activity

In this study, the cytotoxic effects of different squaramides were tested against diverse cancer cells, such as HGC-27, HeLa, T98 and U87 cells, and non-cancer cells, such as EK293, MDCK and Vero cells. The best results were observed in a disubstituted squaramide that showed an IC₅₀ of 1.81 μM against HGC-27 cells, which is a considerably lower value than the IC₅₀ values observed in the rest of the cell lines. Therefore, this squaramide and its derivatives could be promising molecules for the treatment of gastric carcinoma.

Furthermore, the mechanism of action of this compound was evaluated. The outcomes indicated that the decrease in cell viability produced by the squaramide is probably caused by G₀/G₁ cell cycle arrest and caspase-mediated apoptosis. Additionally, the cell death produced by this compound was accompanied by autophagy induction and no signs of cathepsin-mediated cell death and necroptosis were observed.