Inhibition of Rho induces iNOS expression and apoptosis in CML cells. (A-B) Rho inhibitor C3 exoenzyme significantly increased iNOS mRNA (A) and protein (B) in total marrow cells from a CML patient. SCH (1 μM) was used to compare the iNOS-enhanced expression by Rho inhibitor and FTIs. (C-D) Inhibition of Rho-induced apoptosis of CML cells. (C) Flow cytometric detection of apoptotic hypodiploid DNA derived from a CML patient. Horizontal bars indicate hypodiploid DNA peak and its percentage. (D) Bars represent percentage of apoptotic cells, enumerated by the TdT assay, after exposure to FTIs (□) and to Rho inhibitor (▦) (cumulative mean percentage ± SEM: 36.2% ± 3% vs 27% ± 2%, respectively; P = .03).