Hepatocyte Growth Factor Inhibits Anoikis of Pancreatic Carcinoma Cells Through Phosphatidylinositol 3-Kinase Pathway

Objectives: Escape from anoikis, apoptosis induced by loss of cell-cell or cell-extracellular matrix interactions, is important in tumor invasion and metastasis. Hepatocyte growth factor (HGF) is known to play a pivotal role in pancreatic carcinomas. This study aimed to determine the antianoikis effect of HGF in pancreatic carcinoma cells. Methods: Antianoikis effect of HGF was evaluated in human pancreatic carcinoma cells in nonadherent culture with or without anti-E-cadherin antibody. Signal pathways were investigated by Western blot analysis and inhibition assay using inhibitors for phosphatidylinositol 3-kinase and p38. Results: Pancreatic carcinoma cells underwent anoikis in nonadherent culture. However, some of the carcinoma cells survived by forming aggregations in suspension. Anti-E-cadherin antibody dissociated the aggregations, and the separated cells underwent additional anoikis. Hepatocyte growth factor inhibited anoikis irrespective of E-cadherin-mediated cell-cell contact. Inhibition of the phosphatidylinositol 3-kinase/Akt pathway abolished the antianoikis effect of HGF. Phosphorylation of Akt was induced by HGF, and the phosphorylated Akt persisted even when E-cadherin was inhibited. Conclusions: Hepatocyte growth factor inhibits anoikis of pancreatic carcinoma cells through phosphatidylinositol 3-kinase pathway in which activation of Akt may be involved. It is thus supposed that HGF may have a potent role in invasion and metastasis of pancreatic carcinoma cells by exerting its antianoikis effect.