Trichosanthin inhibits cell growth and metastasis by promoting pyroptosis in non-small cell lung cancer.

Background: A number of studies have demonstrated that trichosanthin (TCS) can induce apoptosis in numerous types of tumor cell lines. However, whether TCS can induce pyroptosis has not yet been reported. This study aimed to investigate the role of TCS and its inhibitory effect on tumor growth by modulating pyroptosis in non-small cell lung cancer (NSCLC). Methods: Effects of different concentrations of TCS on the cell viability, proliferation, migration and invasion of NSCLC were detected by Cell Counting Kit-8 (CCK-8), colony formation, migration, and invasion assays. Immunofluorescence was used to detect the effect of TCS on the expression of pyroptosis marker protein gasdermin-D (GSDMD)-N in A549 cells. A tumor xenograft animal model was established by injecting A549 cells into nude mice. Results: In the present study, we found that TCS significantly inhibited the proliferation, migration, and invasion of A549 cells in a concentration-dependent manner. In addition, TCS at a high concentration (40 µg/mL) significantly promoted the expression of pyroptosis-related proteins [GSDMD-N, NLR family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), caspase-1, and GSDMD], which showed an inhibitory effect on the pyroptosis of A549 cells. Additionally, we found that necrosulfonamide (NSA) significantly reversed the inhibitory effect of high concentrations of TCS on the pyroptosis of A549 cells. The in vivo experiments showed that TCS effectively reduced the tumor volume and inhibited the expression of Ki-67, whereas it increased the expression of GSDMD-N. Conclusions: Taken together, these results indicated that TCS could inhibit the progression of NSCLC by promoting pyroptosis. These findings provide further information on the possible underlying mechanism of TCS in the treatment of NSCLC.