Abstract

 

GPR78 is an orphan G-protein coupled receptor (GPCR) that is predominantly expressed in human brain tissues. Currently, the function of GPR78 is unknown. In this study, we found that GPR78 was expressed in lung cancer cells and functioned as a novel regulator of lung cancer cell migration and metastasis. We found that knockdown of GPR78 in lung cancer cells suppressed cell migration. Moreover, GPR78 modulated the formation of actin stress fibers in A549 cells in a RhoA- and Rac1-dependent manner. At a molecular level, GPR78 regulated cell motility through the activation of G¥áq-RhoA/Rac1 pathway. We further demonstrated that knockdown of GPR78 inhibited lung cancer cell metastasis in vivo. These findings suggest that GPR78 is a novel regulator for lung cancer metastasis and may serve as a potential drug target against metastatic human lung cancer.