ARHGEF17 and lung carcinoma: Given that ARHGEF17 was proven to be essential for the migratory and invasive responses elicited by LPA in metastatic lung cancer cells (Fig. 2, D–H), and our previous studies demonstrating that heterotrimeric Gi proteins participate in the migratory response to this agonist (50); we hypothesized that Gi activates ARHGEF17 via Gβγ (Fig. 4A).