Semaphorins?are a class of secreted and membrane?proteins?that act as?axonal?growth cone?guidance molecules. They primarily act as short-range inhibitory signals and signal through multimeric?receptor?complexes. They are usually cues to deflect axons from inappropriate regions, especially important in?neural system?development. The major class of proteins that act as their receptors are called?plexins.SEMA3G possesses anti-migration and anti-invasion ability. SEMA3G inhibited tumor cell migration and invasion, which may be obtained through cell autonomous or paracrine mechanisms, and SEMA3G is a potential target for antitumor migration and invasion.