Revisiting chemotherapy: drug persisters arise from metabolically and transcriptionally distinct cell populations in leukemia
Relapses caused by drug resistance is the major barrier for effective treatment of most solid tumors and hematological malignancies. In acute myeloid leukemia (AML), we showed that mitochondrial adaptation is a critical determinant of resistance to cytarabine (AraC).
We proved that this is associated with an increased availability of respiratory substrates and cofactors, mitochondrial biogenesis and transfer from stromal cells, iron-sulfur cluster biogenesis, BCL2 dependency, and ROS detoxification upon inflammatory and stress responses.
We next demonstrated that the ectonucleotidase CD39 and extracellular ATP promote AraC resistance by enhancing mitochondrial biogenesis and OxPHOS activity through the activation of a cAMP-/ATF4-mediated mitochondrial stress response (MSR). Interestingly, OxPHOS metabolism and MSR are also determinants of the response to IDH- and BCL2-selective inhibitors.
Additionally, our group and others have identified several other markers of relapse-initiating cells (RICs) that are metabolite sensors or transporters such as CD36, SLC7A5 and SLC1A3, which underlined metabolic dialogues between resistant blasts and their microenvironment. This provided access to a broad range of respiratory substrates including fatty acids, glutamine, aspartate, lactate and/or glucose to support the energetic metabolism of RICs. More specifically,
CD36 was positively associated with extramedullary dissemination of leukemic blasts in vivo and in patients. Furthermore, CD36 inhibition reduced metastasis of blasts and prolonged survival of chemotherapy-treated mice. Our ongoing work is highlighting that the role of metabolic and transcriptional trajectories of three distinct RIC populations, diverse tissue metabolomic ecosystems and the impact of ketogenic diet during the course of disease progression.
Pour en apprendre davantage
Directeur de recherche Inserm, responsable de l’équipe “Métabolisme et résistance thérapeutique dans les leucémies aiguës myéloïdes” au Centre de recherches en cancérologie de Toulouse (CRCT)