Alexander Waclawiczek, Aino‐Maija Leppä, Simon Renders, Ines Bergerweiss, Karolin Stumpf, Barbara Betz, Susanna Gabrowski, Frank Y. Huang, Maria‐Eleni Lalioti, Bendix Hempel, Markus Sohn, Heikki Kuusanmäki, Vera Thiel, Julia M. Unglaub, Rabia Shahswar, Sarah Richter, Maike Janssen, Darja Karpova, Elisa Donato, Halvard Bonig, Christoph Röllig, Simon Raffel, Michael Heuser, Michael Hundemer, Mika Kontro, Ann-Kathrin Eisfeld, Tim Sauer, Nina Cabezas‐Wallscheid, Carsten Müller-Tidow, Andreas Trumpp
The BCL-2 inhibitor venetoclax has transformed the treatment of acute myeloid leukemia (AML), but relapse due to resistance of leukemic stem cells (LSCs) remains a major challenge. By molecular and functional profiling of LSCs from >150 patients, we identify four LSC subtypes. These mirror distinct hematopoietic lineage stages, which determine the expression ratio between the venetoclax target BCL-2 and resistance-inducing proteins MCL-1 and BCL-xL (MAC-score). Longitudinal analyses reveal that venetoclax resistance mostly arises in LSCs through plasticity toward a megakaryocytic/erythroid-progenitor (MEP)-LSC state that switches survival dependency from BCL-2 to BCL-xL. In rare cases, mature monocytic/dendritic (MoDe)-LSCs, found within LAMP5 + monocytic AMLs, drive venetoclax resistance. LSC subtyping improves genetic risk stratification and provides subtype-specific therapies: venetoclax-resistant MEP-LSCs respond to BCL-xL inhibitors, whereas MoDe-LSCs are sensitive to MEK1/2 inhibition. Our findings reveal four distinct LSC types with unique vulnerabilities and propose biomarker-guided treatment strategies that complement genetic profiling to overcome venetoclax resistance.