Figure 1.

Semaphorin signals on the road to cancer invasion and metastasis. Semaphorins play a regulatory role on the main elements driving cancer progression. They can be seen as “stop” or “go” signals for tumor cells, as well as for stromal cells in the tumor microenvironment. The scheme features some examples of the semaphorin signals implicated so far. More information on the implicated receptors and functional activities of the different semaphorins are summarized in Table 1.