Betulinic acid suppresses NGAL-induced epithelial-to-mesenchymal transition in melanoma.

Betulinic acid (BA) exhibits antitumoral activity by blocking proliferation, invasion, and angiogenesis. However, the impact of BA on epithelial-to-mesenchymal transition (EMT), a hallmark of cancer metastasis induced among others by neutrophil gelatinase-associated lipocalin (NGAL), remains unknown. The present study aimed at determining the effect of BA on NGAL-induced EMT. In A375 melanoma cells, BA downregulated mesenchymal markers, increased epithelial markers, and inhibited cytoskeletal reorganization. In addition, BA limited endogenous NGAL production and further suppressed EMT induced by exogenously added NGAL and the corresponding invasive cellular phenotype. In conclusion, BA interferes with EMT-associated changes, a mechanism to antagonize invasive melanoma cells.