A cell-permeable (quinoxalinylmethylidene-D-tryptophanyl)hydrazide that directly targets Rho GEF binding domain (Kd = 354 nM for RhoA), thereby prevents Rho from interacting with its GEFs (including LARG, DBL, LBC, p115 RhoGEF, and PDZ RhoGEF), but not p190RhoGAP, RhoGDI, or its effectors (ROCK,…