SMO and chronic myelogenous leukemia, BCR-ABL1 positive: Zhao et al. and Dierks et al. clearly demonstrated that Smo inhibition in murine models of CML, either by genetic knock-out or by pharmacological inhibition with the non-clinical SMO inhibitor cyclopamine, potently inhibited the propagation of leukaemic cells and the reconstitution of disease in secondary transplant models leading to prolonged survival of transplant recipients24, 27.