Hepatoma-derived growth factor stimulates podosome rosettes formation in NIH/3T3 cells through the activation of phosphatidylinositol 3-kinase/Akt pathway.

ABSTRACT

Hepatoma-derived growth factor (HDGF) stimulates the migration, invasion and metastasis in several types of cancer cells. However, the mechanism underlying HDGF-stimulated migration remains unclear. In this study, we investigated the influence of HDGF on cytoskeleton remodeling and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway in non-transformed NIH/3T3 cells. Exogenous HDGF promoted the migration and the formation of dorsal ruffles and podosome rosettes. Besides, HDGF supply increased the PI3K expression and Akt phosphorylation in dose- and time-dependent manners. Application of LY294002, a PI3K inhibitor, attenuated the HDGF-induced migration, dorsal ruffles and podosome rosettes formation. Consistently, the HDGF-overexpressing NIH/3T3 transfectants exhibited significantly increased motility and elevated PI3K/Akt activities, which were repressed by LY294002 or adenovirus-mediated overexpression of endogenous PI3K antagonist, PTEN. In summary, HDGF elicits the activation of PI3K/Akt signaling cascade, thereby promoting cytoskeleton remodeling to stimulate cellular migration.