Fig. 7. Tranexamic acid (TA) stimulated the extracellular signal-regulated kinase (ERK) signaling pathway and decreased protein levels of microphthalmia-associated transcription factor (MITF). Protein levels of ERK, phosphorylated ERK (p-ERK), and MITF after TA treatment were evaluated by western blot analysis using B16F10 cells. Sustained activation of ERK was observed; in particular, p-ERK was elevated until 24 hours after TA treatment. MITF protein level decreased in a time-dependent manner.