Polysaccharide isolated from persimmon leaves (Diospyros kaki Thunb.) suppresses TGF-β1-induced epithelial-to-mesenchymal transition in A549 cells

In the present study, to verify the effect of polysaccharides derived from persimmon leaves (PLE) at epithelial-to-mesenchymal transition (EMT), A549 cells were treated with TGF-β1 alone or co-treated with TGF-β1 and PLE (50 and 75 μg/mL). PLE-treated cells showed higher expression of E-cadherin and lower expression of N-cadherin and vimentin compared to TGF-β1-treated cells by inhibiting the levels of transcription factors, including Snail, Slug, and ZEB1, all associated with EMT. PLE also significantly decreased migration, invasion, and anoikis resistance through TGF-β1 mediated EMT suppression, whereby PLE inhibited the levels of MMP-2 and MMP-9 while cleaving PARP. These inhibitory effects of PLE against EMT, migration, invasion, and anoikis resistance were determined by activating the canonical SMAD2/3 and non-canonical ERK/p38 signaling pathways. Therefore, these results suggest that PLE could be used as a potential chemical therapeutic agent for early metastasis of lung cancer in vitro.