A polysaccharide from Hedyotis diffusa interrupts metastatic potential of lung adenocarcinoma A549 cells by inhibiting EMT via EGFR/Akt/ERK signaling pathways.

In this study we investigated the potential effects of a polysaccharide (HDP) from Hedyotis diffusa on the metastasis in human lung adenocarcinoma A549 cells. HDP (25, 50 and 100 μg/ml) significantly suppressed the cell adhesion, invasion and migration of A549 cells in a dose dependent manner by downregulation of matrix metalloproteinase (MMP-2 and MMP-9) and upregulation of tissue inhibitors of metalloproteinase (TIMP-2 and TIMP-9). Moreover, HDP effectively downregulated the protein expressions of epithelial-mesenchymal transition (EMT) markers (N-cadherin and vimentin), and upregulated E-cadherin protein expression, which is involved in interrupting EGFR/Akt/ERK signaling pathways, as well as inhibiting COX-2 protein expression. All these results demonstrated that HDP might be a novel anti-metastatic agent for NSCLC treatment.