Anti-Melanoma Activity and Potential Mechanism of Purified Potato Protease Inhibitor

Melanoma is one of the most lethal cancers originating from melanocytes. Its incidence and mortality have been rising rapidly for several decades and have posed a serious threat to human health. Current melanoma treatments are hindered by the scope of application, low efficiency, high cost, and toxic side effects. Due to their affordability and minimal side effects, natural bioactive compounds derived from plants are promising candidates for melanoma treatment. This study aims to delve into the isolation, purification, and characterization of potato proteins and to explore their potential in melanoma treatment. Two potato proteins, patatin PP-1 and aspartate protease inhibitor PP-2, were isolated and purified by a newly developed method in this work, and their physicochemical properties were systematically characterized. Both potato proteins showed great antiproliferative activities and migration inhibition effects on melanoma cells. Meanwhile, Western blotting results illustrated that they could induce endogenous cell apoptosis by regulating the Bax/Bcl-2 pathway. Notably, aspartate protease inhibitor PP-2 demonstrated the best performance in inhibiting the growth and migration of melanoma cells, which might be attributed to the combined effect of its significant antioxidative activity and the inhibition effect of certain necessary protease activities in melanoma. This study provides valuable insights for developing nutraceuticals and therapeutic strategies against melanoma, which can lead to breakthroughs in melanoma treatment.