Anticancer effects of non-steroidal anti-inflammatory drugs against cancer cells and cancer stem cells.

Certain non-steroidal anti-inflammatory drugs (NSAIDs) are known to have anticancer effects. However, it is unclear whether all NSAIDs have anticancer effects, and thus far, very few studies have compared the antitumor effects among multiple NSAIDs. Therefore, we aimed to identify NSAIDs that enhance the anticancer effect of cisplatin (CDDP); the effects of 17 NSAIDs in lung cancer cells and their spheroids as cancer stem cells (CSCs) were evaluated. Some of the NSAIDs showed cytotoxic effects against A549 and SBC-3 cells and their CDDP-resistant cell lines (A549/DDP and SBC-3/DDP cells, respectively). In addition, co-addition of CDDP and celecoxib, which showed cytotoxic effects, increased the resistance to CDDP by increasing SLC7A11, which is one of the CDDP resistance mechanisms, in A549/DDP and SBC-3/DDP cells. On the other hand, celecoxib also showed antitumor effects on the spheroids of A549/DDP and SBC-3/DDP cells, and enhanced the antitumor effect of CDDP while increasing the mRNA levels of SLC7A11. Moreover, diclofenac was also cytotoxic and enhanced the cytotoxic effect of CDDP in cancer cells and CSCs. In conclusion, some NSAIDs including celecoxib and diclofenac may enhance the therapeutic efficacy of CDDP.