Flurbiprofen axetil is involved in basal‐like breast cancer metastasis via suppressing the MEK/ERK signaling pathway

Abstract Flurbiprofen axetil is commonly utilized in clinical practice as one of the nonsteroidal anti‐inflammatory drugs (NSAIDs) and is included in multimodal analgesia regimens postbreast cancer surgery. Numerous NSAIDs have been studied for their potential to both promote and inhibit cancer. Given the variability in their effects on tumors, further investigation into the specific role of flurbiprofen axetil is warranted. Therefore, the primary objective of this study was to assess the impact of flurbiprofen axetil on basal‐like breast cancer (BLBC) metastasis and elucidate the underlying molecular mechanisms involved. The BLBC metastasis mouse model was established by caudal vein injection of tumor cells. The lung metastasis of breast cancer in mice and the effect of flurbiprofen axetil were assessed by in vivo bioluminescence imaging, hematoxylin and eosin staining and immunohistochemistry. In vitro, the results of flurbiprofen axetil on the proliferation, migration, and invasion of MDA‐MB‐231 human breast cancer cells and BT‐549 human breast cancer cells were assessed by colony formation assay and transwell assay. The effects of flurbiprofen axetil on several tumor metastasis‐related signaling pathway proteins were examined by western blot, and the reversal extent of the flurbiprofen axetil effect by Ro 67‐7476 (ERK phosphorylation agonist) was detected by transwell assay. The results showed that flurbiprofen axetil significantly inhibited BLBC lung metastasis in mice. Flurbiprofen axetil similarly inhibited breast cancer cell migration and invasion in vitro but did not affect their proliferation. Mechanistic investigations have revealed that flurbiprofen axetil exerts a noteworthy inhibitory influence on the MEK/ERK pathway while exhibiting no significant alteration in the expression of other pathway proteins intricately associated with epithelial–mesenchymal transition. In conclusion, the inhibitory effect of flurbiprofen axetil on BLBC metastasis is characterized by its selectivity in targeting the MEK/ERK signaling pathway rather than exerting a broad impact on the global signaling pathway.