In contrast to S1P1, S1P2 inhibits migration in many cell types, including vascular endothelial and smooth muscle cells as well as tumor cells, via activation of Rho and inhibition of Rac (Okamoto et al., 2000; Arikawa et al., 2003; Goparaju et al., 2005; Lepley et al., 2005; Tamama et al., 2005; Takashima et al., 2008). This evidence concerns the gene S1PR2 and neoplasm.