ARHGEF2 and leukemia: A number of these regulators have been shown to be identical in immune cells and cardiomyocytes (e.g., LARG (leukemia-associated RhoGEF), GEF-H1/Lfc (Lbc’s first cousin), PDZ-RhoGEF, p190RhoGAP, and Vav1) [49,55], while others were found specifically in immune cells (e.g., RhoA-GAP, Myo9B, and Rho-GEF7) [56].