Piezo1 activation using Yoda1 inhibits macropinocytosis in A431 human epidermoid carcinoma cells

Macropinocytosis is a type of endocytosis accompanied by actin rearrangement-driven membrane deformation, such as lamellipodia formation and membrane ruffling, followed by the formation of large vesicles, macropinosomes. Ras-transformed Cancer cells efficiently acquire exogenous Amino acids for their survival through macropinocytosis. Thus, inhibition of macropinocytosis is a promising strategy for Cancer therapy. To date, few specific agents that inhibit macropinocytosis have been developed. Here, focusing on the mechanosensitive ion channel Piezo1, we found that Yoda1, a Piezo1 agonist, potently inhibits macropinocytosis induced by epidermal growth factor (EGF). The inhibition of ruffle formation by Yoda1 was dependent on the extracellular CA²⁺ influx through Piezo1 and on the activation of the calcium-activated Potassium Channel KCa3.1. This suggests that CA²⁺ ions can regulate EGF-stimulated macropinocytosis. We propose the potential for macropinocytosis inhibition through the regulation of a mechanosensitive channel activity using chemical tools.