CTSL and lip and oral cavity carcinoma: As reported in Figure 7A,B, platyphyllenone treatment significantly reduced the pression of cathepsin L; however, no effect of platyphyllenone was observed on the expression levels of cathepsins S, A, and Z. To further analyze the effect of cathepsin L in platyphyllenone-mediated migration inhibition, we subsequently overexpressed cathepsin L in oral cancer cells and treated the cells with platyphyllenone.