Abstract
BACKGROUND Src and Fn14 are implicated in the aggressiveness of non-small cell lung cancer (NSCLC) cells, yet the molecular mechanism is not fully understood. MATERIAL AND METHODS The proliferation, migration, and invasion of HCC827 cells with Src knockdown were examined in vitro. The expression of Fn14 and the activation of NF-κB signaling pathway in Src-silenced HCC827 cells were detected by western blot. The role of Fn14 in Src-regulated cell migration/invasion and activation of NF-κB signaling was investigated by overexpressing Fn14 in Src knockdown NSCLC cells. Furthermore, the pro-metastatic role of Src was validated in a NSCLC metastasis mouse model. RESULTS Knockdown of Src inhibited the proliferation, migration, and invasion of HCC827 cells, which was associated with reduced levels of Fn14, p-IκBα, p-IKKβ, and nuclear NF-κB p65. Overexpression of Fn14 restored the potential of migration and invasion as well as the activation of NF-κB signaling in Src-silenced NSCLC cells. In addition, silencing of Src suppressed lung metastasis of HCC827 cells in mice, and inhibited the expression of Fn14 and nuclear translocation of NF-κB p65 in vivo. CONCLUSIONS The data demonstrated that the Src/Fn14/NF-κB axis plays a critical role in NSCLC metastasis.