Phycocyanin inhibits pancreatic cancer metastasis via suppressing epithelial-mesenchymal transition and targeting Akt/β-catenin pathway.

According to our previous research, phycocyanin (PC) could inhibit pancreatic tumor growth obviously. However, little is known about the effects of phycocyanin on pancreatic tumor metastasis. This study was aimed to investigate whether phycocyanin inhibits pancreatic cancer cells' metastasis and the potential underlying mechanisms. Human pancreatic carcinoma cell lines PANC-1 and BxPC3 were treated with phycocyanin (5, 10, 20, and 40 μM) for 48 h or 72 h. BALB/c nude mice were inoculated intravenously with luciferase-PANC-1 cells to establish a tumor metastasis model. BALB/c nude mice were also inoculated subcutaneously with PANC-1 cells to establish a xenograft tumor model. Our results indicated that (1) phycocyanin inhibited migration, invasion, and movement of pancreatic cancer cells in vitro, and tumor metastasis in mouse xenograft tumor model; (2) phycocyanin significantly changed cell morphology and epithelial-mesenchymal transition (EMT) phenotype in pancreatic cancer cells; (3) phycocyanin decreased the phosphorylation level of Akt and the level of nuclear β-catenin. Moreover, administration of Akt activator SC79 counteracted the inhibitory effect of phycocyanin on the migration of pancreatic cancer cells, associated with the reversal of epithelial-mesenchymal transition and Akt/β-catenin signaling pathway. Taken together, our results suggest that phycocyanin inhibits pancreatic cancer metastasis via suppressing epithelial-mesenchymal transition and targeting the Akt/β-catenin pathway.