PROS1 and chronic myelogenous leukemia, BCR-ABL1 positive: In CML, abnormal tyrosine kinase-directed phosphorylation and mislocalization of cell cycle proteins have been implicated in deregulation of the cell cycle in Bcr-Abl expressing cells, which means that CML quiescent LSCs are TKI resistant and represent a Bcr-Abl kinase-independent disease reservoir (Cramer et al., 2008).