Purpose: Paeonol, a natural product derived from the root of Cynanchum paniculatum  (Bunge) K. Schum and the root of Paeonia suffruticosa  Andr. (Ranunculaceae) has attracted extensive attention for its anti-cancer proliferation effect in recent years. The present study examined the role of paeonol in suppressing migration and invasion in pancreatic cancer cells by inhibiting TGF-β 1/Smad signaling.
Methods: Cell viability was evaluated by MTT and colonial formation assay. Migration and invasion capabilities were examined by cell scratch-wound healing assay and the Boyden chamber invasion assay. Western Blot and qRT-PCR were used to measure the protein and RNA levels of vimentin, E-cadherin, N-cadherin, and TGF-β 1/Smad signaling.
Results: At non-cytotoxic dose, 100 μM and 150 μM of paeonol showed significant anti-migration and anti-invasion effects on Panc-1 and Capan-1 cells (p< 0.01). Paeonol inhibited epithelial-mesenchymal-transition by upregulating E-cadherin, and down regulating N-cadherin and vimentin expressions. Paeonol inhibited TGF-β 1/Smad signaling pathway by downregulating TGF-β 1, p-Smad2/Smad2 and p-Smad3/Smad3 expressions. Further, TGF-β 1 attenuated the anti-migration and anti-invasion capacities of paeonol in Panc-1 and Capan-1 cells.
Conclusion: These findings revealed that paeonol could suppress proliferation and inhibit migration and invasion in Panc-1 and Capan-1 cells by inhibiting the TGF-β 1/Smad pathway and might be a promising novel anti-pancreatic cancer drug.
Keywords: paeonol, pancreatic adenocarcinoma, TGF-β 1/Smad signaling, epithelial-mesenchymal-transition, Cynanchum paniculatum