As PIM kinases regulate the mTOR signalling at least via two independent pathways, involving PIM2‐mediated phosphorylation of TSC2 (S1798) and PIM1‐mediated phosphorylation of PRAS40 (T240), PIM inhibition attenuates mTOR activity and decreases CXCR4/mTOR‐mediated chemotaxis.43, 44 Collectively, these data indicate that PIMs play an important role in CLL cell life cycle, linking microenvironment with CXCR4‐mediated migration and pro‐survival signalling. This evidence concerns the gene PIM1 and B-cell chronic lymphocytic leukemia.