This contrasts with the agonist activity of the small molecule 3αDOG that requires ECD autoproteolysis for its ability to promote Ga12/13 activation, 5) GPR56 is internalized in a β-arrestin independent manner and 6) despite the distinct signaling profile of 10C7 we found that it stimulated endogenous GPR56, which resulted in RhoA activation in breast cancer cells (BT20) confirming its agonistic activity in a pathophysiological context. This evidence concerns the gene ADGRG1 and breast cancer.