Subsequently, we researched the changes of these key proteins associated with PI3K/Akt/mTOR signaling pathway in A375 cells after Polyphyllin I treatment, the results manifested that PI3K/Akt/mTOR signaling pathway was inhibited, the expressions of p-PI3K, p-Akt and p-mTOR was distinctly decreased, but the total protein levels of PI3K, Akt, and mTOR had no significant difference in melanoma A375 cells. Here, MTOR is linked to melanoma.