In NPC, MSC-derived exosomes are associated with elevated expression of fibroblast growth factor (FGF)-19, enhancing tumour growth, migration, and metastasis through the activation of the FGF19-fibroblast growth factor receptor 4 (FGFR4)-dependent ERK signaling cascade and promotion of EMT (49). This evidence concerns the gene FGFR4 and nasopharyngeal carcinoma.